A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
6 Review of Literature
2 REVIEW OF LITERATURE
21 Introduction
We are very well aware that there are thousands of wall paintings existing in
various part of India dating from the prehistoric times to the present date Wall paintings of
Ajanta Ellora and Bagh are world famous Besides these well known examples there are
thousands of other mural paintings which are extremely important but are less
known (Agrawal and Pathak 2001)
Murals are paintings made on walls of caves and palaces while miniatures are
small-sized colorful intricate handmade illumination Murals are considered to be the
earliest evidence of Indian paintings which are unearthed as the symbol of ancient
civilization The term mural is derived from the Latin word ldquomurusrdquo which means wall
The paintings carried out on the walls are known as mural paintings (Mini 2010) Mural
paintings reflect the feelings of Indian spirituality prismed through the age-old mythologies
and spirituality
22 History of wall and mural painting
221 History of wall painting
The history of art of painting in India can be traced back to pre historic and proto
historic times The earliest specimen was found in caves and rock shelters found admits
rocky hills These paintings are dated from 1200 BC to the tenth century AD (Mathpal
1984 Misra et al 1977) Artifacts found at Mohenjodaro and Harappa has traces of
natural pigments suggestive of the use of colors in pre-Aryan art These cave paintings has
quite a wide distribution though all the paintings do not belong to one period Rock shelter
paintings are usually seen on back walls arranged in horizontal lines and often with many
super impositions of successive styles The earliest paintings go back to at least 550 BC
Ajantan art the tradition of which extends more than two millennia from the second
century BC to the present represents the flowering of Indian mural paintings History of
wall paintings in India is studied through its evolution from Ajanta to Kerala Ajanta
paintings considered to have been executed between the 2nd
century BC and 5th
centaury
AD Murals of 6th
centaury AD was found at Badami (Karnataka) and Sittannavasal Jain
cave temple (Tamilnadu)Murals of Narthamala Vijayalaya Chozeswara belongs to
9th
century AD and murals of Brihadeeswara temple Tanjore (Tamilnadu) belongs to
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
7 Review of Literature
11th
century AD Murals seen in Kerala are dated between 16th
17th
and 19th
century AD
(Sasibhooshan 2006)
The most important sites of rock paintings in North India are at Bimbetka Gwalior
Tikla Ayra Bhanpura Rampura Singhauli Bhojpur Adamgrh Delware and Mirzapur
In south India they are found at Mehaboob Nagar (Andhrapradesh) Edakkal Marayoor
and Perimkadavila (Kerala) Mallampadi (Tamilnadu) and Bellary (Karnataka)These
paintings were considered as the early models of mural paintings The mural painting of
Sittannavasal Badami Lepakshi Tanjore Vijayanagar and Kerala has a lot of similarities
Style colour theme and technique of mural painting varied with different dynasties their
ruling period and important painting sites are given belowThe important mural painting
site Ajantha cave 9 amp10 was made during the ruling period from 2nd
BC to 2nd
AD of
Satavahana dynasty Vaishnava cave in Badami in the ruling period from 6th
-8th
AD
belongs to early western Chalukyas During 7th
-9th
AD Pallava dynasty in Kailasanatha
temple Kancheepuram was considered to be as one of the dominant mural painting site in
Southern India Similarly other South Indian dynasties early Pandya between 7th
and
9th
AD and early Chera from 8th
to 9th
AD highlighted their mural paintings at
Sittannavasal cave temple and Thirunandikkara cave temple respectively Mural paintitngs
at Kailasanatha temple Ellora from 8th
- 10th
AD was made by the dynasties of
Rashtrakuta The familiar mural paintings at Brihadeeswara temple Thanjavur and
Vijayalaya Choliswaram temple Narthamalai was carried out by the chola dynasty
between the period of 9th
and 13th
AD Another biggest dynasty called Vijayanagara
betweeen 14th
and 17th
AD made numerous mural paintings at Vidharbha temple
Lepakshi Varadaraja Perumal temple Kancheepuram Vitthala temple Hampi and Sri
Ranganatha tenple Srirangam Nayakarsquos dynasty ruled inthe period from 17th to 18th AD
established the mural paintings in Kapardisvara temple Tiruvanjuli and later murals of
Thanjavur and Kancheepuram Finally medivial Kerala (blend of Hoysala Chalukya and
Vijayanagara paintings) in 16th
and 18th
AD carried out the mural paintings at Tripayar
temple Ettumanur temple Thiruvanchikulam temple Panayanarkavu temple
Mattancherry Padmanabhapuram and Krishnapuram palace (Sivaramamurthi 1994)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
8 Review of Literature
222 History of mural painting
The first paintings were Cave Paintings Ancient peoples would decorate walls of
protected Caves with paint made from dirt or charcoal mixed with spit or animal fat In
Cave paintings the pigments (often carbon black or ochre) stick to the wall partially
because the pigment gets trapped in the porous wall and partially because the binding
media (the spit or fat) dries adhering the pigment to the wall Over the years countless
graves unearthed by archaeologists exposed bodies covered in red pigment or chunks of
pigment buried alongside the bodies Red associated with blood the most life sustaining
of body fluids was the appropriate color to symbolize lifes meaning and end The word
Hematite (the source of many iron oxide pigments) is derived from the Greek word hema
meaning blood (Chakarabarti 1980)
Wall paintings have been cultural expressions of human creation throughout
history from the earliest beginnings such as rock art extending up to present day murals
Throughout history humans have used the most beautiful and durable stones for
monumental buildings Beginning in the sixth century BC marbles extracted from the
Pentelikon quarry became a common building material Abundant limestone and marble
quarries enabled the ancient Greek architects to build the Acropolis and Roman architects
to build the Forum (Saiz 2002)
Figure-21 Cave painting
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
9 Review of Literature
Figure-22 Mural painting
The oldest known Maya murals are also the most recently discovered Murals
found at the Preclassic site of San Bartolo Guatemala date to 100 BC The church of San
Pietro and the ldquooratoriordquo of San Benedetto are believed by most scholars to date from the
third quarter of the 11th century During the last decade of the same century that some
changes were made to the edifice of the church and it was decorated with mural paintings
and stucco reliefs deep in the jungle of southeastern Mexico archaeologists were surprised
that the murals are about 1350 years old
St Agatharsquos Complex was one of the preferred sites since it consists of the
hypogean environment embellished by a significant number of wall paintings some dating
back to the fourth century AD The Catacombs of St Paulrsquos constitute a complex of
interconnected underground Roman cemeteries that were in use up to the 4th century AD
There are a few surviving murals and ochre inscriptions from late Roman and early
medieval periods Decorated tablets and reliefs adorn the graves (Zammit et al 2008) The
uncovering of paintings was made from the middle of the 19th century until the 1960s
23 Indian murals
History of wall paintings in India is studied through its evolution from Ajanta to
Kerala Ajanta paintings considered to have been executed between the 2nd
century BC and
5th
century AD Murals of 6th
century AD was found at Badami (Karnataka) and
Sittannavasal Jain cave temple (Tamilnadu) Murals of Narthamala Vijayalaya Chozeswara
belong to 9th
century AD and murals of Brihadeeswara temple Tanjore (Tamil Nadu)
belong to 11th
century AD Murals seen in Kerala are dated between 16th
17th and
19th
century AD (Sivaramamurthy 1994)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
10 Review of Literature
India has one of the greatest traditions of painting of the ancient world Murals and
miniature are the two different forms of arts which intrinsically related to Indian painting
tradition The earliest evidence of murals is the beautiful frescoes painted on the caves of
Ajanta and Ellora also on the Bagh caves and Sittanvasal The oldest mural paintings date
is about 3000 years BC (Sasibhooshan 2006)
The number of wall paintings in each state of India is very large and they are
suffering from all types of deterioration and damage but in comparison facilities for their
preservation are much too small This is a very serious problem The main objective of the
present study is to develop a protective bio-based gel (Rajagopalan 2008)
24 North Indian murals
North India has a rich heritage of Mural paintings even before the Mughal period
The murals at the Vishnu Temple located at Madanpur in Lalitpur district of Uttar Pradesh
of 12th century AD reveals the skillful hands of the painters In Eastern India there are
many evidences of wall and panel paintings describing Buddhist and non- Buddhist
themes In Arunachal Pradesh and Tripura sublime mural works have been found which
needs further study Ladakh is known for its wall paintings in Alchi and Hemis
monasteries made on 11th-12th century and the Spiti Vally in Himachal Pradesh is known
for its Buddhist paintings in the Gomphas of Tabo Monastery (Havell 1982)
Ajanta is known to be the fountain head and inspiration of Buddhist paintings
across the whole of Asia There are fragments of paintings of the time of Ajanta which
survive at many Buddhist cave sites including Pitalkhora near Ellora in Maharashtra The
magnificent Kailashnath temple had been hewn out of a mountain at Ellora in the 8th
centuryThe Kashmiri style was mainly responsible for the lovely wall paintings still seen
in the beautiful monasteries at Alchi Mangyu and Sumda in Ladakh in the Tabo
monastery in the Spiti valley and in the Nako monastery in Kinnaur district Himachal
Pradesh On the western edge of the trans-Himalayan plateau in Spiti is the monastery
complex of Tabo This appears to be one of the first among the 108 monasteries built by
Yeshe It is dated around 996 AD There are also paintings of the late 9th century in the
Jain caves at Ellora (Spink 2009)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
11 Review of Literature
Figure-23 Ajanta caves
Figure-24 Mural Painting of Ajanta caves
Ellora Caves Maharashtra belong to the highest achievements of mankind both
regarding the engineering skills and arts Some 2000 years ago Pitalkhora Caves
(Maharashtra) were among the largest temple complexes in India These 11 - 14 caves
were created in 250 BC - 4th century AD In 4th century AD temples were adorned with
beautiful murals especially fine paintings have been preserved on columns of Cave 3
Traces of murals are in Cave 6 as well Already the oldest group of caves here - Buddhist
caves from 630 - 700 AD - contain paintings of Buddhist panteon Remnants of paintings
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
12 Review of Literature
are seen in the most beautiful temple - Cave 16 Kailasanatha circa 760 - 860 AD Some
Jain temples - Cave 32 (Indra Sabha) Cave 33 - contain remnants of valuable murals from
800 - 1000 AD - this artwork marks the end of ancient period in the Indian art and
beginning of medieval art (Baskaran 1975)
Figure-25 Ellora caves
There are surviving mural paintings from the 17th century onwards in Rajasthan
The verdant Pahari hills saw the finest continuation of the tradition of murals in India The
18th and 19th century paintings on the walls of the Rang Mahal in Chamba are among the
best surviving examples of Pahari murals The 18th century paintings on the walls of the
Viranchinarayan Temple at Buguda are some of the finest surviving murals of that period
in India
Figure-26 Paintings on the walls of the Rang Mahal in Chamba
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
13 Review of Literature
The most important sites of rock paintings in North India are at Bimbetka Gwalior
Tikla Ayra Bhanpura Rampura Singhauli Bhojpur Adamgrh Delware and Mirzapur
In South India they are found at Mehaboob Nagar (Andhrapradesh) Edakkal Marayoor
Perimkadavila (Kerala) Mallampadi (Tamilnadu) and Bellary (Karnataka)These
paintings were considered as the early models of mural paintingsThe mural painting of
Sittannavasal Badami Lepakshi Tanjore Vijayanagar and Kerala has a lot of similarities
(Sasibhoosan 1987)
25 South Indian murals
South India also got rich tradition of mural paintings In the reign of Cholas
Vijayanagaras and Nayakas this art reached the climax The Deccan art of Bijapur
Hyderabad and Golconda schools were influenced by the Mughal traditions and later by
European idiom Maratha murals are also shaped under the Mughal traditions and
employed oil as medium The Mural art of Kerala vividly depicted on the walls of temples
and monuments show the traces of European affinity In Tamil Nadu almost all the extent
examples of frescos have been done on rock surfaces and stone walls This is a crucial
factor in determining the quality of frescos (Havell 1982) The ceiling of the Virupaksha
temple in Hampi is covered with paintings of the 15th century The paintings on the ceiling
of the mandapa of Lepakshi temple are some of the finest mural paintings of the medieval
period in India Legends associated with Siva and Parvati Krishna and Rama were painted
on the walls of palaces and temples in Kerala from the 16th to 19th century Mural
paintings were made on the walls of all the palaces within the magnificent Orccha fort The
Raj Mahal was completely adorned with mural paintings of the 17th century
Figure-27 Virupaksha temple in Hampi
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
14 Review of Literature
Figure-28 Ceilings of Virupaksha temple Hampi
The murals on the walls of the navaranga (the central pillared hall) depict stories
from Bhagavatha and are excellent examples of 19th
century Mysore paintings The
Mallikarjunaswamy temple on the hill is one of the Panchalingas of Talakad and the
temple has a beautiful mural painting on the wall of the temple The Dariya Daulat Bagh
has excellent mural painting (Sasibhoosan 1987)
Figure-29 Paintings on the walls of Jagan mohan palace Mysore
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
15 Review of Literature
Figure-210 Painting of Raja woodeyar era
Kerala mural paintings are the frescos depicting mythology and legends which are
drawn on the walls of temples and churches in South India principally in Kerala Ancient
temples churches and palaces in Kerala South India display an abounding tradition of
mural paintings mostly dating back between the 9th to 12th centuries The murals of
Thirunadhikkara Cave Temple (now ceded to Tamilnadu) and Tiruvanchikulam are
considered the oldest relics of Keralarsquos own style of murals Fine mural paintings are
depicted in temples at Trikodithanam Ettumanur Vaikom Pundarikapuram
Udayanapuram Triprangode Guruvayoor Kumaranalloor Aymanam the Vadakkunathan
temple in Trichur and the Sri Padmanabhaswamy temple at Thiruvananthapuram Other
mural sites are in the churches at Edappally Vechur Cheppad and Mulanthuruthy and at
palaces such as the Krishnapuram Palace near Kayamkulam and the Padmanabhapuram
Palace
Figure-211 Kerala murals
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
16 Review of Literature
Figure-212 Murals paintings of Kerala temples
There are wall paintings in Badami in the Bijapur district Karnataka Some
excellent paintings exist in the Jain caves at Sitanavassal in Puddukkottai District of Tamil
Nadu Tamil Nadu gave exuberant and glorious expression to themes relating to Siva in the
temples of Panamalai and Kailashanatar in Kancheepuram In the 9th century Jain cave of
Sittannavasal in Tamil Nadu there is a marvellous lotus pond painted on the ceiling In
the heart of the Brihadeeswara temple in Thanjavur Tamil Nadu protected by massive
walls of stone are the finest paintings of the theme of Siva ever painted towards the end of
the 10th century (Sivaramamurthi 1992)
Figure-213 Kancheepuram Mural paintings
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
17 Review of Literature
Figure-214 Sculpture of Mahabalipuram
26 Methods of mural painting
In the history of mural several methods have been used The Buon fresco technique
consists of painting in pigment mixed with water on a thin layer of wet fresh lime mortar
or plaster The pigment is then absorbed by the wet plaster after a number of hours the
plaster dries and reacts with the air it is this chemical reaction which fixes the pigment
particles in the plaster After this the painting stays for a long time up to centuries in fresh
and brilliant colors A Secco painting is done on dry plaster The pigments thus require a
binding medium such as egg (tempera) glue or oil to attach the pigment to the wall
Mezzo-fresco is painted on nearly-dry plaster which is defined by the sixteenth-century
author Ignazio Pozzo as ldquofirm enough not to take a thumb-printrdquo so that the pigment only
penetrates slightly into the plaster Ancestral Hopi village archaeologists found that
fourteen kivas had painted murals and multiple layers of murals on the walls some with up
to twenty-seven layers of murals (Saturno 2006)
The colors used in painting are generally obtained from plants and minerals
Among them only such colors which are lime resistant are suitable for mural painting The
selection of proper colors for a mural painting is an important part of the work as the
longevity the painting depends on it Only mineral colors are preserved for a long time
which could be the reason for use of those colors in early days As per ldquoShilpa ratnardquo and
ldquoAgnipuranardquo the colors used in mural painting are white black red yellow blue and
green Yellow and red are from yellow ochre and red ochre Blue is generally indigo or
china blue White is the prepared wall and black is the carbon soot Mural paintings have
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
18 Review of Literature
survived centuries only on account of the identification and use of those colors which does
not have any reaction with lime (Miraseth 2006)
Originally three types of brushes were made and used flat medium and fine Flat
brushes were made from hairs behind calfrsquos ear the medium from the bottom of goats
belly and the fine brush from delicate blades of grass However in due course of time and
change use of easily available brushes from commercial market and shading of the
original colours can be distinctively noticed The use of blue colour is also noticed over the
passage of time The paintings have been brought down from the walls to plywood cloth
paper and other frames for easy to make and use purposes (Chakarabarti 1980)
27 Themes of mural painting
The subjects and themes in the murals are centered on the Hindu pantheon of Gods
and Goddesses drawn from description in the invocatory verses or Dhyana Slokas More
common representations are of Vishnu in different incarnations Ganesha and
manifestations of Siva We see murals in the Pallimanna Siva Temple devoted to Siva-
Parvatirsquos marriage the Ramayana Story being narrated on the walls of the Mattancheri
palace in the Sankara Narayana the Mahabharata is retold Murals are various scenes from
the Hindu epics and also the frolics of Lord Krishna
It would be interesting to bring into account the influence of the mural paintings on
Christianity On various churches like the St Georgersquos Orthodox Church has Christian
murals bringing out biblical characters and narrating stories from the scriptures Mar
Sabore and Afroth Church at Akapparambu in the outskirts of Ernakulam also have murals
of scenes from the bible Interestingly StMaryrsquos Church at Kanjoor has on both sides of its
entrance a battle scene between the armies of Tipu Sultan and of the English East India
Company It is also apparent that the history of Kerala Murals has its origin in the temple
walls and thus a study of Kerala Murals is not complete without pondering on the
architecture of Kerala its association with the murals (Warrier 2011)
28 Technique used in mural paintings
Indian murals executed on walls of caves structural temples walls of palaces were
based on highly developed techniques Mural painting is a composite structure of these
three basic layers the support the ground and the pigment layer In case of wall painting
the wall itself is the support This is followed by the layer or layers of plaster which
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
19 Review of Literature
constitute the ground The pigment layer is the one which contains the picture The support
is the wall which may be rock surface in a cave or a structural one These stone surfaces
which serve as carriers are rough or uneven This unevenness is itself an advantage as it
provides ldquotoothrdquo to hold the plaster on the surface The uneven surface of the wall has to be
made uniform with layers of plaster in successive gradation of fineness There is generally
one layer of rough plaster followed by one or more layers of fine plaster Ground or plaster
is a term used to mean the surface material of a wall or building which is applied as a
plastic mass made by mixing certain materials with water letting the mass set by drying
carbonation or hydration The active or setting components of plaster are commonly clay
which sets by drying lime which sets by carbonation gypsum and pozzolana which sets by
hydration (Mini 2010)
There are different mixtures for rough plaster In all the mixtures clay limestone
lime and shells in powdered form serve as the matrix The particles of which are held
together by the organic materials like gum glue extracts from barks etc are in fact
adhesives The fine plaster layer requires more careful preparation because it is the layer on
which the pigments are laid to make the picture ldquoShilparatnardquo suggest a mixture of conch
Oyster shells or white clay with gum of neem or slaked lime and coconut water Here the
consolidation is effected by the carbonation of slaked lime ie it absorbs carbon dioxide
from air and becomes carbonate Mural paintings were lime-washed from the 17th until the
beginning of 19th century A few paintings in vaults were never lime-washed for example
at Taby and Floda painted by the medieval painter Albertus Pictor (Mini 2010)
All the paintings have certain basic common characteristics There has to be a wall
or rock surface called support over which the artist goes to work A plaster base called
ground of varied thickness is laid on the support The ground may consist of one or more
layers The strength and life of the whole mural depended up on this ground over which the
painting was done It is the process of applying the final painting on the ground determines
the character of the mural whether it is fresco or tempera The mural painting is done
usually by creating wall surface free of any previous oil or paint by using solvent or by
sand blasting The brick wall is first plastered with mixture of lime and sand in the ratio of
12 A mixture of egg yolk vinegar oil colour is used in dry plaster
There are at least six stages before a Kerala Mural Painting is complete Lekhya
Karma is the first stage where sketching by pencil or crayon is done The second stage is
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
20 Review of Literature
the Rekha Karma which enhances the outlines of the sketching done The third stage called
Varna Karma breathes life into the painting with its colours Here all colours are
appropriately filled in The colouring of the human figures is done according to the
characters and their common virtues The divine and noble characters (Saatvik) are painted
in green those inclined towards power and wealth (Raajasik) is painted in shades of red
lowly mean characters (Tamasik) in white and demons in black In the fourth stage or the
Vartana Karma shading is done Fifth stage called the Lekha Karma brings us to the final
outline of the painting which is usually in black The final and the finishing touches stage
are called Devika Karma (Warrier 2011)
29 Dyes used in mural painting
Indians have been considered as fore runners in the art of natural dyeing Natural
dyes find use in the colouring of textiles drugs cosmetics etc Owing to their non-toxic
effects they are also used for colouring various food products In India there are more
than 450 plants that can yield dyes In addition to their dye-yielding characteristics some
of these plants also possess medicinal value Though there is a large plant resource base
little has been exploited so far Due to lack of availability of precise technical knowledge
on the extracting and dyeing technique it has not commercially succeeded like the
synthetic dyes (Siva 2007)
The color materials on the mural paintings in ancient India were derived from the
natural materials like terracotta chalk red ochre and yellow ochre mixed with animal fat
The dyes for painting is prepared such as white from lime Black from carbon soot of
lamps Red and yellow from minerals Blue from indigo ferra Deep red from lac A fine
coating of resin is done after the painting in order to make a shining appearance Egg yolk
and vinegar was mixed with oil colors and painted on dry plaster (Krishnakumar 1999)
Although plants exhibit a wide range of colours not all of these pigments can be
used as dyes Some do not dissolve in water some cannot be adsorbed onto fibres whereas
others fade when washed or exposed to air or sunlight It remains a mystery why plants
reward us with vibrant dyes India has a rich biodiversity and it is not only one of the
worldrsquos twelve mega diversity countries but also one of the eight major centres of origin
and diversification of domesticated taxa It has approximately 490000 plant species of
which about 17500 are angiosperms more than 400 are domesticated crop species and
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
21 Review of Literature
almost an equal number their wild relatives Thus India harbours a wealth of useful
germplasm resources and there is no doubt that the plant kingdom is a treasure-house of
diverse natural products One such product from nature is the dye (Siva 2007)
Many natural dyestuff and stains were obtained mainly from plants and dominated
as sources of natural dyes producing different colours like red yellow blue black brown
and a combination of these Almost all parts of the plants like root bark leaf fruit wood
seed flower etc produce dyes It is interesting to note that over 2000 pigments are
synthesized by various parts of plants of which only about 150 have been commercially
exploited Nearly 450 taxa are known to yield dyes in India alone of which 50 are
considered to be the most important ten of these are from roots four from barks five from
leaves seven from flowers seven from fruits three from seeds eight from wood and three
from gums and resins Some important dye-yielding plant habitats their distribution and
colouring pigment (Siva 2007)
The dye is generally prepared by boiling the crushed powder with water but
sometimes it is left to steep in cold water The solution then obtained is used generally to
dye coarse cotton fabrics Alum is generally used as a mordant Flowers of Butea
monosperma (Lam) Taubert yield an orange-coloured dye which is not fast and is easily
washed away For the purpose of colouring the material is steeped in a hot or cold
decoction of the flowers A more permanent colour is produced either by first preparing the
cloth with alum and wood ash or by adding these substances to the dye-bath The dye
indigo is produced by steeping the plant in water and allowing it to ferment This is
followed by oxidation of the solution with air in a separate vessel Mallotus philippinensis
muell yields an orange colour used for dyeing silk and wool To prepare the annatto dye
from B orellena the fruits are collected when nearly ripe The seeds and pulp are removed
from the mature fruit and macerated with water Thereafter they are either ground up into
an lsquoannatto pastersquo or dried and marketed as annatto seeds Sometimes when the seeds and
pulp are macerated with water the product is stained through a sieve and the colouring
matter which settles out is collected and partially evaporated by heat and finally dried in
the sun (Sowbhagya 2002)
The predominant colors used in rock art and cave art are black (from charcoal soot
or manganese oxide) yellow ochre (limonite) red ochre (hematite or baked limonite) and
white (kaolin clay burnt shells powdered gypsum or powdered calcium carbonate) All of
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
22 Review of Literature
theses pigments may be used on leather or raw hide as well Early cave art in Seminole
Canyon was monochromatic in red and as culture grew more sophisticated the color
palette expanded Blue Orange Brown Green and Purple are the most common colours
used in Ajantha murals White Pink Gold are occasionally represented mineral earths
containing ferric oxide and copper carbonates were used as source of red yellow and green
colours There is also evidence to establish that root of Rubia cardifolia and leaves of
Indigofera tinctoria were used as source for red and blue colours (Nayer et al 1999)
Many colors of pigments were obtained from both organic and inorganic sources in
ancient times and used to paint various surfaces such as braintan leather clothing and
accoutrements rawhide the human body etc Blue color was obtained from powdered
azurite and lapis duck manure and certain clays Fine Blue-green clay was obtained from
deposits near Mankato Michigan Organic sources of blue include Turkeys Tail a
greenish blue polypore that grows on dead decaying wood (not tannish ones) Native
Americans get Indigo from either Guatemala or Ecuador which was traded well up onto
Kansas long before the Spanish ever set foot here American Indigo has purple tones to it
but IndianJapanese indigo has green tones Berries and crushed flowers were also used to
obtain blue color by rubbing the plant material directly on the leather
An organic source of red was Cochineal It was native west of the Mississippi and
is produced from the bodies of small insects that grow on the prickly pear cactus Ladys
Bedstraw gives a good vermillion red color Harvest the roots dry them out clean the mud
etc off of them and then grind the roots really fine then soak them to extract the red
coloring The key here is drying the root first Blood was also used as red pigment Pucoon
roots also yield a red pigment (Smith 2002) Red ochre the reverse original red colours are
due to variations in iron oxide (or) calcite content and to redox conditions in the firing
produced Brown coloured ceramics owe their colour to maghemite and must be
considered as a fabrication defect due to the position of the ceramic piece in a zone where a
reducing atmosphere prevailed in the course of firingRed pigments were produced from
iron oxides like hematite or limonite and from ochre Hematite was the most frequently
used mineral It occurs in the form of aggregates of small red crystals or in the form of
bigger black crystals which are difficult to crush white was obtained mostly from
kaolinite or illite (Clottes et al 1990)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
23 Review of Literature
210 Biodetoriation of mural paintings
Historic items often contain natural biodegradable materials and have histories of
exposure to moist conditions These two conditions make them amenable to microbial
attack Microbial colonization may damage the building or the cultural asset
(Salonen 2001) Biodeteriogens are organisms involved in deterioration of artifacts They
are very specific for each type of artifact in accordance with its chemical structure and
environment They also have different nutritional requirements and act directly or
indirectly on the substrate The adhesion of microorganisms to a substrate is the result of
cell hydrophobicity and of excreted polymeric substances contained by sheaths capsules
and slimes (Colao 2005)
The surviving wall paintings and decorations in subterranean environments around
Malta are rather scarce (Buhagiar 1986 1993 1998) These include those at St Paulrsquos
Catacombs (Zammit 2008) St Agatharsquos Crypt and Catacombs (Camilleri 2001)
San Catald Catacombs Tac-Cghaqi Abbatija tad-Dejr (Buhagiar 1993) all in Rabat the
cave-sanctuary in Mellieħa (Buhagiar 1987) and the Ħal Saflieni Hypogeum in Paola
(Pace 2000) Previous studies conducted on wall paintings and decorations in Maltese
Palaeo-Christian Catacombs have involved their manufacturing techniques (Muscat 2005)
However to date limited systematic studies have been conducted into the biodeterioration
in Maltese Palaeo- Christian Catacombs The only such studies ever conducted in Malta
concerned the biodeterioration of works of art in catacombs have been carried out at St
Agatharsquos Crypt and Catacombs in Rabat (Zammit et al 2008 Psaila 2006)
Microorganisms can be responsible for the destruction of monuments buildings
and cultural heritage assets including the decay of concrete cement stones mural
paintings etc These microorganisms are not only related with biodeterioration but water-
damaged indoor building materials are frequently colonized by complex bacterial
communities and may emit mixed bioaerosols into the indoor air (Jimenez 2000) It is
well known that mural paintings are colonized by micro-organisms and can be severely
damaged by such growths (Ciferri 1999) A large number of fungal (gt50) and bacterial
taxa (70) have been detected in indoor environments Over 50 bacterial species and 14
genera novel to science were reported in the past 10 years from indoor air and historic
items indicating bacterigravea in these enviroments are as yet only fragmentarily known
(Salonen 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
24 Review of Literature
Traditionally the study of microflora which causes this biodeterioration was based
on classical cultivation methods that were mainly useful to study the physiological
potential of microorganisms but do not provide information on all microbial communities
to be found in excavated artifacts Indeed many studies using culture-independent
techniques which cultivate microorganisms from different environments may often
represent only minor components of the microbial community as a whole It is generally
accepted that cultivation methods recover less than 1 of the total microorganisms present
in environmental samples (Ward et al 1990 Amann et al 1995) Hence microbial
investigations based only on cultivation strategies cannot be regarded as reliable in terms
of reflecting the microbial diversity present in objects of art (Osburn et al 2011)
Early workers suggested that the presence of living microorganisms on stone
increased its susceptibility to damage through their water-binding capacity It has recently
been reported that the mineralogy porosity surface roughness and capacity to collect
water and organic materials control its bioreceptivity and tendency to biodeterioration
(Diakumaku 1995) In addition environmental factors as temperature light pH and
relative humidity affect the number and type of colonising species (Tiano et al 1995) and
hence the progress of colonisation Biofilms on decayed stones consist on mixed microbial
populations embedded in a polymeric matrix Fungi algae filamentous and unicellular
bacteria are found in these complex communities A variety of bacteria have been isolated
from different stone samples confirming the dominance of Gram-positive organisms
especially spore-forming bacteria such as Bacillus and filamentous actinomycetes
(Ripka 2005)
In cultivation studies of deteriorated mural and rock paintings bacterial isolates
have frequently been attributed to the genus Bacillus (Weirich 1989 Tate and Rebrikova
1991 Gonzalez et al 1999 Heyrman et al 1999 Jimenez et al 2000) Other studies that
have included DNA-based techniques to characterize the bacterial community involved in
biodeterioration have shown that a substantial part of the bacterial population is made up of
so far unknown species (Altenburger et al 1996 Rolleke et al 1996 Gurtner et al 2000
Heyrman and Swings 2001) (Heymann et al 2003)
Many potential mycotoxin producers have been detected in air and items from
indoor environments with histories of exposure to moisture for example species of
Acremonium Alternaria Aspergillus Chateomium Fusarium Eurotium Paecilomyces
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
25 Review of Literature
Penicillium Scopulariopsis Stachybotrys Trichoderma Verticillium and Wallemia
(Peltola et al 2001 Pieckova et al 2001) Not all strains of one species produce
mycotoxins and different strains may produce different toxins Whereas toxin producing
strains are frequent in crops and outdoor vegetation toxin producing isolates from indoor
environments and non living assets have only been reported of the species Aspergillus
versicolor (Nielsen et al 1998) Stachybotrys chartarum Nikulin (1997) and
Trichoderma harzianum (Peltola et al 2001) Streptomyces griseus strains producing
valinomycin occur in environments where humans can get exposed
(Andersson et al 2002) The biological properties and toxicity mechanisms of cereulide
were identical to those by valinomycin (Mikkola et al 1999 Salonen et al 2001)
The genus Paenibacillus was first proposed by Ash et al (1993) and its description
was emended by Shida et al (1997) The genus Paenibacillus is under intensive taxonomic
investigation with ten species having been formally described in the last year Heyrman amp
Swings (2001) isolated a strain originally classified as Paenibacillus sp LMG 19508
from biodeteriorated mural paintings in the Servilia tomb at the Roman necropolis of
Carmona in Seville Spain (Smerda et al 2006) Building stone and wall paintings contain
a variety of hydroscopic salts including carbonates chlorides nitrates sulfates etc
dispersed within the porous material or locally concentrated These salts are solubilised
and migrate with the water in and out of the stone Due to changes in physical parameters
the so called salt efflorescences appear on the surfaces providing extremely saline
environments and building niches for settlement of halophilic microorganisms Halite and
other hygroscopic salts can retain considerable quantities of moisture when entrapped in
the building materials and thus favouring the bacterial growth (Ripka 2005)
It is demonstrated that water-damaged indoor building materials contained
substances of microbial origin extremely toxic to eukaryotic cells and large quantities of
several microbial species known to be potentially toxic or immunopotentiating These
include peptidoglycans Gram-negative endotoxin β-13-D glucans lipoglycans and
teichoic acids and mycotoxins (Jimenez 2000) In turn these microorganisms can mediate
the crystallization process These crystallizations can produce destructive effects Some
salts may crystallize or recrystallize to different hydrates which occupy a larger space and
exert additional pressure producing cracking powdering and flaking
(Jimenez and Laiz 2000)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
26 Review of Literature
211 Types of deterioration on mural paintings
The frescos represent a variety of ecological niches where primary colonization is
due to photoautotrophic and chemolithoautotrophic microorganisms followed by
secondary colonization due to heterotrophic bacteria that obtain nutrients from various
sources (metabolites of autotrophic bacteria airborne organic contamination animal faeces
and organic compounds in the paint layers themselves) Microbial-induced deterioration
processes cause structural as well as aesthetic damage to wall paintings such as the
discoloration of materials the formation of crusts on surfaces and the loss of material
(Sarro et al 2006 Osburn et al 2011) Halophilic bacteria and archaea were thought to
be found only in extreme environments like salt lakes or black smokers However it has
been shown that mural paintings and stones are a common habitat for extremely salt
tolerant and moderate halophilic (Ripka 2005) Microbial induced deterioration processes
can cause different kinds of alterations such as discolouration of materials the formation of
crusts on surfaces and the loss of material which leads to structural damage (Ripka 2005)
First of all microorganisms can cause severe problems due to the excretion of aggressive
metabolic products such as organic or inorganic acids Secondly material components can
be used as substrates for microbial metabolism Exoenzymes such as cellulases proteases
tannases beta-glucosidase produced by fungi and bacteria are responsible for hydrolysis of
cellulose and proteins Further examples are mechanical processes caused by swelling and
shrinking of slime or mycelia penetrating inside plaster of the painting resulting in loss of
cohesion and detachment of the paint layer (Rolleke 1996 Gurtner et al 2000)
Table-21 Microbial damage on mural paintings (Rolleke 1996)
S No Damage Microbial activity
1 Green brown red grey
surface layers (patinas)
Pigments produced by microorganisms (intra-or
extracellular) as chlorophyll and carotinoids
2 Dislodging of painting layers Use of organic binders as nutrient and energy
source
3 Acid attack of carbonates Acid produced by fungi or bacteria
4 Discolouration of pigments Redox-reactions induced by fungi and
bacteria
5 Loss of paint layer Growth of microorganisms deep into the plaster
6 Hydrolysis of synthetic
polymers Chemoorganotrophic activity of bacteria and fungi
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
27 Review of Literature
Discolorations are caused by excretion of pigments and microbiologically induced
reductionoxidation-processes (Krumbein et al 1990) Degradation of the bindings is
followed by reduction of stability Oxidation of ammonium and reduced sulphur
compounds results in acidification of the environment such as Sulphuric acid and the
variety of organic acids produced by the heterotrophs cause solubilization of calcareous
binding material and chelation of metal ions (Bock et al 1993) It is now well recognised
that wall paintings can be deteriorated by microorganisms (Ciferri 1999)The growth of
microorganisms essentially results in two types of damage aesthetic and structural
Aesthetic damage implies pigment discoloration stains and formation of a biofilm on the
painted surface Structural damage is observed as cracking and disintegration of the paint
layer formation of paint blisters and degradation of support polymers or of glues and
binders resulting in detachment of paint layer from the support The colonization of mural
paintings by bacteria and other microorganisms can have different causes Provided that
favorable environmental conditions occur nutrients for heterotrophic bacteria and fungi
can be available from metabolites of autotrophic bacteria from airborne contamination and
dripping water from animal faeces but also from organic compounds in the paint layer
itself
212 Methods of studying biodeterioration
It is now well recognized that wall paintings may be deteriorated by
microorganisms as established by several studies that linked the observed damage with the
microbial community present as reviewed by Ciferri (1999) Despite this knowledge a
reliable characterization of bacteria associated with such damage is often lacking To
obtain greater insight into the bacterial community involved in biodeterioration of mural
paintings three sites (from the necropolis at Carmona Spain and the Saint-Catherine
chapel of the castle at Herberstein Austria) were sampled In previous studies from these
sites 385 isolates were analysed by fatty acid methyl ester GC and representatives of
different fatty acid clusters were further studied by 16S rRNA gene sequencing
(Heyrman and Swings 2001) Several of these representative strains showed the highest
sequence similarity with members of the genus Arthrobacter (Heyrman et al 2005)
Jimenez and Samson (1981) analysed the microbial flora of a large fresco painted
in the late 1920s in the monastery ldquoSanta Maria de la Rabidardquo (Huelva Spain) exhibiting
two types of deterioration white efflorescence and green-to-black stains
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
28 Review of Literature
Tate and Rebrikova (1990) thought autotrophic nitrifying bacteria to be the first colonisers
of damaged frescoes and building materials in the cathedral of the nativity of the Virgin in
the Pafnutii-Borovskii monastery (Russia) The bulk of research on biodeterioration of
mural paintings has focused on explaining the observed phenomena by analysing the
microflora present Following this approach a precise characterisation of the
microorganisms using a polyphasic approach was never the first goal
Only a few studies included genomic fingerprinting (16S rDNA sequence analysis)
for the characterisation of bacteria associated with damage on mural paintings
[Rolleke (1996) Pinar et al (2001)] Previous studies based on culture-dependent
techniques showed that the flora present on frescos are fungi (predominant species of
Penicillium Aspergillus Cladosporium and Engyodontium) (Guglielminetti et al 1994)
bacteria (predominant species of Bacillus Arthrobacter Micrococcus Streptomyces and
Pseudomonas) (Heyrman et al 1999) cyanobacteria and eukaryotic algae (species of
Nostoc Lyngbya and Chlorophyceae) (Arino et al 1996 Calvo et al 1993) The killing
effect of an antimicrobial agent on a microorganism can be assessed in several ways
(1) Lethal activity may be expressed as the rate of killing by a fixed concentration
of drug under controlled conditions This rate is determined by measuring the number of
viable bacteria at various time intervals The resulting graphic depiction is known as the
time-kill curve Bacterial killing rates are in part dependent on the class of antibiotic and
the concentration of this agent With certain classes of antibiotics (eg aminoglycosides
and fluoroquino-lones) the rate of killing increases with increased drug concentrations up
to a point of maximum effect This is termed concentration-dependent bactericidal activity
In contrast the killing rates of szlig-lactam agents and vancomycin are relatively slow and
continue only as long as the concentrations are in excess of the MIC This rate of killing is
termed time-dependent bactericidal activity
(2) The minimal concentration of drug needed to kill most of the viable organisms
after incubation for a fixed length of time (generally 24 hours) under a given set of
conditions is the most common estimation of bactericidal activity and is known as either
the minimal bactericidal concentration (MBC) or the minimal lethal concentration (MLC)
It will be referred to in this document as the MBC Unfortunately the definition of the
MBC (999 killing of the final inoculum) is somewhat arbitrary and separates the
bacteria into two populations ndash a segrega-tion which might not have biological relevance
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
29 Review of Literature
The determination of the MBC moreover is so subject to methodologic variables that the
clinical relevance of MBCs is nearly impossible to assess particularly for certain pathogen
and drug combinations (eg Staphylococci and beta-lactam agents)
(3) The serum of a patient receiving an antibiotic may be tested against the
infecting microorganism This can be done using time-kill curve methodology (ie serum
bactericidal rate) or using dilution methodology (ie serum bactericidal titer) The
principles of these methods as well as the influence of biological and technical factors are
similar (Barry et al 1999)
213 Microbial flora associated with deteriorated mural paintings
A great deal of research has been done in this field mainly by using cultivation dependent
methods However by using culture-dependent methods only a very small proportion of
microorganisms can be obtained Far less than 1 of organisms in the environment can be
cultivated by standard cultivation techniques (Pace 1996) Recent studies have shown that
culture-dependent techniques yielded mainly sporeforming bacteria suggesting that plating
leads to an over estimation of the number of spore-forming bacteria A wide number of
investigations have shown that in addition to chemical and physical processes
microorganisms play a major role in degradation of objects of art such as paintings stone-
works wood paper masonry leather parchment glass and metal (Ripka 2005)
A) Bacteria
In general growth of diverse organisms on mural paintings is supported by
humidity slight alkaline pH values and the presence of organic and inorganic nutrient
sources (Weirich 1989) In mural paintings pigments are suspended in water or oil often
binders such as casein and milk are used and they are supplied on the damp lime plaster
(Ciferri 1999) The calcium carbonate formed on contact with air consolidates the
pigments Thus frescos contain mainly inorganic components While chemoautotrophic
nitrifiers and thiobacilli obtain their energy for growth by oxidizing ammonium and
reducing sulphur-compounds respectively heterotrophic bacteria and fungi depend on
organically bound carbon [Tate et al (1991) Lazar (1971) Petushkova et al (1986)
Jimenez et al (1981)] Thus primary colonization of photoautotrophic Cyanobacteria
chemolithoautotrophic nitrifying bacteria and sulphuric acid producing thiobacilli represent
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
30 Review of Literature
the first supply of organic matter The death and lysis of such bacteria promotes the
secondary settlement of heterotrophic bacteria and fungal populations (Calvo et al 1991)
Bacteria may derive from plants or pollen as many sequences obtained in this study
gave high score similarities with bacteria isolated from plants like Moraxella osloensis
Enterobacter cloace Enterobacter agglomerans and Pantoea endophytica Bacteria may
also derive from animal faeces like flies Bacillus Pseudomonas Aeromonas and Panteoa
(Ripka 2005) As Lazar and Dumitru (1973) reported studying mural paintings in a
Romanian monastery the genera Bacillus Arthrobacter and Pseudomonas have been
proved to produce salt efflorescences and were even considered to cause the blanching
phenomenon of frescoes (Jimenez et al 2000) Predominant bacterial genera are Bacillus
Streptomyces Arthrobacter Micrococcus and Pseudomonas [Weirich (1989)
Tate et al (1990) Arroyo et al (1997) Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
B) Fungi
It may be concluded that there is wide variety of fungal forms present on mural
paintings but Aspergillus and Alternaria were found dominating from all the experimental
sites next to them were Cladosporium Drechestera Fusarium Curvularia Chaetomium
Memnoniella Mycelia sterelai Pencillium Emericella Stachybotrytis Trichoderma
Phoma Monodictys Humicola and Epicoccum (Garg et al 1995)
The fungal genera most commonly found in lists of isolated taxa given in literature
are Alternaria Aspergillus Chaetomium Cladosporium Fusarium Penicillium and
Verticullum [Weirich (1989) Tate et al (1990) Guglielminetti et al (1994)
Garg et al (1995) Berner et al (1997) Ciferri (1999)] Some fungi having hard fruiting
bodies represented by sclerotia pycnidia perithecia cleistothecia and stroma could
organize themselves inside the painted layer Many fungal forms having such structures
were identified from our experimental sites viz Emericella nidulans A flavus
Chaetomium sp and Phoma sp etc These structures with little increase in humidity may
cause swelling in the paint film (Garg 1995)
Strains of species of Alternaria and Cladosporium both of them identified on the
mural paintings of the Palace of Schoumlnbrunn are the most common genera isolated from
stone and mural paintings in indoor environments with standard cultivation methods
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
31 Review of Literature
(Ventosa 2004) Saprophytic species of the genus Cladosporium are among the most
abundant fungi isolated in saltern samples Commonly isolated Cyanobacteria belong to
Nostoc and eukaryotic algae to Lyngbya and members of the Chlorophyceae such as
Chlorella Pseudococcomyxa and Pseudopleurococcus [Gorbushina et al (1987)
Calvo et al (1993) Arino et al (1996)]
They grow optimally on media with low water activity due to high salt or sugar
concentrations seem to propagate 70 vegetatively in the salterns and are thus
halotolerantosmotolerant species rather than simple flush-through occurrences
Cladiosporum herbarum was frequently isolated from hypersaline waters dead and dying
plant material air soil food fruit cereals paint and textiles (Ventosa 2004)
C) Algae
Most of the painted areas in temperature climate became covered with green algae
(Pleurococcus Protococcus and Trentopholia) while under tropical conditions blue green
algae of the genera Oscillatoria and Sytonema predominated (Garg 1995) The main
factors which contribute to the growth of algae on wall paintings are the presence of
moisture in the plaster as well as availability of visible light These conditions are quite
prevalent in the tropical climate but in temperature regions also algal growth on wall
paintings have been reported [Tonolo et al (1961) Pietrini et al (1991)]
D) Actinomycetes
Usually literature refers to specific aspects eg the occurrence of cyanobacteria
and algae in caves with natural openings to sunlight or those with artificial lighting fungi
and so forth Actinomycetes have been considered to be mainly confined to soils where
they find their natural habitat but despite intensive studies there are still many gaps in our
knowledge of the role played by actinomycetes in soil processes and biodegrations of
murals cave paintings (Groth et al 1999) In addition halophilic bacteria actinomycetes
and cyanobacteria are also capable of growing on salt-affected mural paintings
(Karbowska 2003)
Monte and Ferrari (1993) reviewed the mechanisms of biodeterioration in tombs
and underground churches The role of actinomycetes in the deterioration of frescoes in
hypogean environments was stressed by Agarossi et al (1985) Monte and Ferrari (1993)
Giacobini et al (1987) described the serious damage suffered by a whole series of famous
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
32 Review of Literature
frescoes in underground environments Actinomycetes were isolated from these mural
paintings located in crypts caves and tombs About 200 strains of actinomycetes were
isolated 60 of which were identified The most frequent species were Streptomyces albus
S cinereoruber S griseolus S vinaceus and some members of the Nocardia genus
Heterotrophic bacteria and actinomycetes were the most abundant microorganisms
on the frescoes of Etruscan tombs (Agarossi et al 1985) Bettini et al (1977) studied
some of the oldest Etruscan tombs (7th to 4th century BC) and found white-grey patinas
and spots from streptomycetes in the mural paintings They related the biodeterioration to
the microclimatic conditions (eg lower temperatures high RH) Monte and Ferrari (1993)
considered that colonization of the mural paintings was the result of selective competitive
and inhibitory dynamics among different microorganisms under different and changing
environmental conditions The pigments excreted by some actinomycetes were responsible
for the violet stains found on the walls of tombs in Tarquinia Similar stains were observed
in one of the Roman tombs the Circular Mausoleum the Necropolis of Carmona Spain
from which a Streptomyces sp producing violet pigments in culture media was isolated
214 Identification of biodeteriogens
The possibility of pigments and biodeteriogens identification in frescos and stone
monitoring is offered mostly by vibrational spectroscopy infrared thermography laser
induced fluorescence (LIF) laser induced breakdown spectroscopy (LIBS) XRF (X-Ray
Fluorescence) IR and UV emission Among them laser based methods allowing for in
situ or remote characterization of artwork surface were applied successfully for
prospecting diagnosis and maintenance (Colao et al 2005) The rep-PCR fingerprinting
of the isolates allowed determination of their genotypic diversity Studies that have
compared rep-PCR genomic fingerprint analysis with DNAndashDNA relatedness studies have
shown that the two techniques yield results that are in close agreement [Nick et al (1999)
Rademaker et al (2000)] These studies therefore suggest that rep-PCR fingerprinting can
be used as a genomic screening method to differentiate at the species level and to select
representatives for DNAndashDNA reassociation experiments (Heymann et al 2003)
The characterisation of bacteria was for example often limited to isolation from
group-specific media followed by microscopy [Sorlini et al (1987) Weirich (1989)
Tate et al (1990) and in more recent studies to morphological and physiological
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
33 Review of Literature
characteristics including miniaturised and automated systems such as API and BIOLOG
[Arroyo et al (1997) Jimmenez et al (2000) and Laiz et al (2000)] or to
chemotaxonomic characteristics [Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
Wagner et al (1994) demonstrated that conventional microbiological efforts can
fail to isolate all microorganisms present in natural samples DNA-based techniques used
to identify microorganisms have revealed only a smaller fraction of bacteria isolated from
artworks (Ward et al 1990 Rolleke et al 1996) Bacterial identification using molecular
techniques especially those including the sequencing of genes coding for ribosomal
16S rRNA is very important to study bacterial communities found on artefacts One such
method is Denaturing Gradient Gel Electrophoresis (DGGE) of PCR-amplified gene
fragments coding for rRNA (Muyzer et al 1993) that allows the separation of partial
16S rDNA amplified fragments of identical length but different sequence due to their
different melting behaviour in a gel system containing a gradient of denaturants
(Jimenez 2003)
Total genomic DNA was purified for 16S rRNA gene sequencing and rep-PCR
using a slight modification of the method of Pitcher et al (1989) as described by
Heyndrickx et al (1996) rep-PCR genomic fingerprinting was performed with the REP-
and (GTG)5 primers (Versalovic et al 1994) using the PCR conditions described
previously by Rademaker et al (1997) Electrophoresis and pattern analysis were further
performed as described by Heyrman et al (2003) 16S rRNA gene sequencing and
phylogenetic analysis were performed as described by Heyrman and Swings (2001)
Phylogenetic trees were constructed using the BioNumerics software (Applied Maths) by
applying the neighbour-joining and maximum-parsimony methods on a multiple alignment
similarity matrix The stability of relationships was assessed by a bootstrap analysis of
1000 datasets For determination of the G+C content and levels of DNAndashDNA
hybridization approximately 1 g biomass was harvested from agar plates DNA was
purified by using a combination of the protocols of Marmur (1961) and
Pitcher et al (1989) as described by Logan et al (2000) The G+C content of the DNA
was determined by HPLC (Mesbah et al 1989) using the further specifications given by
Logan et al (2000) DNAndashDNA hybridization experiments were performed using a
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
34 Review of Literature
modification of the microplate method of Ezaki et al (1989) as described by
Willems et al (2001)
215 Preservation and conservation
Nowadays the conservation and preservation of our cultural heritage is one of the
world main concerns particularly in Europe The increasing need for non-destructive
investigation tools has become a major issue as sampling is in most cases restricted in
view of the value or the uniqueness of the object Artworks as wall paintings in buildings
and monuments of historical interest are affected by environment physical (temperature
and humidity) and biological factors (biodeteriogens) and by human (pollutant releases)
impact and therefore modified over the time The term ldquoconservationrdquo may have many
different meanings in different fields Every intervention directed to the restoration and
safeguard of works of art is commonly considered as a conservation treatment For
example conservation can involve the cleaning procedures set up by chemists or the photo
documentation of the preservation of historical memory For the appropriate conservation
of works of art even the lighting systems in a museum or the control of the visitorrsquos
movements in a site should be monitored Chemical degradation which induces the flaking
of paintings and deterioration from rain wind dust and other environmental causes is
mainly responsible for the weakening of the porous structure and the surface layers of the
materials used in works of cultural heritage (Colao et al 2005)
216 Conservation history
Wall paintings are an integral part of monuments and sites and should be preserved
in situ Many of the problems affecting wall paintings are linked to the poor condition of
the building or structure its improper use lack of maintenance frequent repairs and
alterations Also frequent restorations unnecessary uncovering and use of inappropriate
methods and materials can result in irreparable damage Substandard and inadequate
practices and professional qualifications have led to unfortunate results It is for this reason
that an appropriate document covering the principles of proper conservation-restoration of
wall paintings is necessary
The Venice Charter (1964) has provided general principles for the conservation-
restoration of cultural heritage The Amsterdam Declaration (1975) introducing the
concept of integrated conservation and the Nara Document on Authenticity (1994) dealing
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
35 Review of Literature
with cultural diversity have expanded these principles Taking into account these and
additional relevant contributions such as the ICOM-CC Code of Ethics (1984) Document
of Pavia (1997) and ECCO Professional Guidelines (1997) the aim of this document is
to provide more specific principles for the protection preservation and the conservation
restoration of wall paintings This document therefore reflects basic and universally
applicable principles and practices and does not take into account particular problems of
regions or countries which can be supplemented at regional and national level by
providing further recommendations where necessary
217 Preservation techniques of the mural paintings
The removal of fat salts varnishes and pollutants from the surfaces of the works
of art are mostly done by chemical and mechanical methods At the end of the 19th
century the practices of restoration methods that do not inhibit further future interventions
was considered acceptable During the 1960s several chemicals such as polymeric resins
were synthesized and applied as a consolidation or protection agents The accepted idea
was that these substances could be removed at any time leaving a completely unaltered
substrate On the basis of origin archaeological objects can be classified as follows
(Carretti 2005)
1 Inorganic It includes siliceous and nonsiliceous materials Archaeological materials
produced from stones terracotta ceramics and glass can be included under siliceous
materials whereas objects made of metals can be included under nonsiliceous inorganic
materials Again metal objects can be classified as ferrous metals and non-ferrous metals
Objects made of iron are termed as ferrous metal objects whereas metal objects made from
other than iron is termed as non-ferrous metal objects
2 Organic It includes archival and anthropological materials Again archival materials
include paper bhojapatra tadapatra textiles wooden objects miniature paintings whereas
anthropological objects include bone and ivory leather feather and fur etc
In the past restoration of paintings and other old artwork often involved application
of acrylic resins to consolidate and protect them One of the most important tasks for
modern restorers is thus to remove these layers because it turns out that acrylic resins not
only by drastically changing the optics of the treated artwork but in many cases they
accelerate their degradation The scientists use an oil-in-water microemulsion with the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
36 Review of Literature
organic solvent para-xylene as the oil component The matrix makes the cleaning agent
viscous so that it cannot enter very far into the pores of a painting (Carretti 2005)
Nanoparticle treatment is the logical evolution of the Ferroni-Dini method
Dispersions of kinetically stable Ca (OH)2 nanoparticles in non-aqueous solvents solved
most of the drawbacks of the microsized powders Stable dispersions of calcium hydroxide
have been successfully applied (replacing polymers) as fixatives to re-adhere lifted paint
layers during many restoration workshops in Italy and in Europe as a consolidant The
FerronindashDini method (two steps the application of a saturated solution of ammonium
carbonate (NH4)2CO3 and the treatment with a barium hydroxide solution Ba(OH)2 also
called the barium method has long been the acknowledged method for the removal of
salts that threaten paintings reinforcing at the same time the porous structure However
commercially available carbonates and hydroxide powders have dimensions of several
micrometres much larger than the pores on the paint surface This means they donrsquot
penetrate the painting well and there is also a risk of damaging the artwork by a white
glaze forming on the surface (Berger 2006) Restoration should provide the reinforcement
of the porous structure and the consolidation of the surface layer of arte facts A few
simple principles can be considered to define the most appropriate restoration method
1) The treatment should be reversible so that one can revert to the original status of the
work of art at any desired time
2) All the applied chemicals must ensure the maximum durability and the chemical
inertness
3) The applied chemicals must invert the degradation processes without altering the
chemical composition of the artefacts and their physico-chemical and mechanical
properties (Baglioni 2006)
218 Commercial preservative used for preservation of mural paintings
Cleaning was done using soft brushes vacuum cleaner and Gumma paine (dough)
a natural latex sponge Areas near the window were very dirty with black soot and were
cleaned with micro fibrous cloths moistened with synperonic N (surfactant alkyl phenol
ethoxylate based on nonyl phenol) and neutralized with clean water In several places the
paint layers had separated from the substrate (exfoli-ation) In that cases loose paint flakes
were stuck back using Paraloid B72 (10 solution in ethanol) as sparingly as possible
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
37 Review of Literature
Paraloid was injected with syringe behind the exfoliated area twice pushed and held back
with Melinex (polyester film) until fixed on the third application (Bionda et al 2002)
In a period of significant growth of molds and intensive efforts to stop the mold
contamination some of the lines of certain paintings were obscured or faded Solutions of
ethanol formalin 91 and Thiabendazole (TBZ) were used but they were not very
effective Para-formaldehyde fumigation was adopted beginning in 1981 to establish an
emergency treatment sensitivity of microorganisms from studied samples was tested
against Desogen by adding 1-3 (v v) in serial dilutions The best concentration
3 (vv) was applied with a brush to prevent spreading of the spores In order to overcome
the problem of fungal attack suitable fungicides carbendizeme or kiroxy-I or 5 solute of
N formaldehyde can be used Shellac solution in spirit or 2 solution of polyvinaycletate
in toluene can be used as preservative and consolidantsTo control insect and fungal attack
fumigants like pyrethrum DDT or 5 solution of sodium penta chlorophenate in kerosene
oil 2 to 5 solution of PVA in toluene or 2 to 5 solution of paraloid B-72 in toluene or
acetone be used (Miura 2009) Microclimatic conditions constitute a critical factor in the
conservation of cave paintings The unstable microclimatic condition is one of the factors
that always affect the state of conservation of mural paintings In the environmental-
monument system knowledge of the functional environment and climatic conditions of the
surroundings are necessary for the identification of causes of decay (Singh 2011)
Furthermore the risk of formation of indoor bioaerosols in residential and public
buildings (offices schools museums etc) has attracted interest in the last years due to
socio-economic as well as sanitary reasons (Ripka 2005) Thus it is important in aspects of
health and maintenance of Cultural Heritage to analyse the complete microflora to further
develop biocides for harmful microorganisms and methods for restoration of damaged
objects of art The biocidal testing was carried out on one representative algal species of
the two classes of algae viz Chlorococcum sp (green) and Chroococcus sp (blue-green)
found to be common in all the samples Efficiency tests were carried out both in liquid as
well as solid media containing algal suspensions by adding a biocide solution of known
concentration and determining the growth of the microorganism after the incubation
period The biocides used for the past studies were
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
7 Review of Literature
11th
century AD Murals seen in Kerala are dated between 16th
17th
and 19th
century AD
(Sasibhooshan 2006)
The most important sites of rock paintings in North India are at Bimbetka Gwalior
Tikla Ayra Bhanpura Rampura Singhauli Bhojpur Adamgrh Delware and Mirzapur
In south India they are found at Mehaboob Nagar (Andhrapradesh) Edakkal Marayoor
and Perimkadavila (Kerala) Mallampadi (Tamilnadu) and Bellary (Karnataka)These
paintings were considered as the early models of mural paintings The mural painting of
Sittannavasal Badami Lepakshi Tanjore Vijayanagar and Kerala has a lot of similarities
Style colour theme and technique of mural painting varied with different dynasties their
ruling period and important painting sites are given belowThe important mural painting
site Ajantha cave 9 amp10 was made during the ruling period from 2nd
BC to 2nd
AD of
Satavahana dynasty Vaishnava cave in Badami in the ruling period from 6th
-8th
AD
belongs to early western Chalukyas During 7th
-9th
AD Pallava dynasty in Kailasanatha
temple Kancheepuram was considered to be as one of the dominant mural painting site in
Southern India Similarly other South Indian dynasties early Pandya between 7th
and
9th
AD and early Chera from 8th
to 9th
AD highlighted their mural paintings at
Sittannavasal cave temple and Thirunandikkara cave temple respectively Mural paintitngs
at Kailasanatha temple Ellora from 8th
- 10th
AD was made by the dynasties of
Rashtrakuta The familiar mural paintings at Brihadeeswara temple Thanjavur and
Vijayalaya Choliswaram temple Narthamalai was carried out by the chola dynasty
between the period of 9th
and 13th
AD Another biggest dynasty called Vijayanagara
betweeen 14th
and 17th
AD made numerous mural paintings at Vidharbha temple
Lepakshi Varadaraja Perumal temple Kancheepuram Vitthala temple Hampi and Sri
Ranganatha tenple Srirangam Nayakarsquos dynasty ruled inthe period from 17th to 18th AD
established the mural paintings in Kapardisvara temple Tiruvanjuli and later murals of
Thanjavur and Kancheepuram Finally medivial Kerala (blend of Hoysala Chalukya and
Vijayanagara paintings) in 16th
and 18th
AD carried out the mural paintings at Tripayar
temple Ettumanur temple Thiruvanchikulam temple Panayanarkavu temple
Mattancherry Padmanabhapuram and Krishnapuram palace (Sivaramamurthi 1994)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
8 Review of Literature
222 History of mural painting
The first paintings were Cave Paintings Ancient peoples would decorate walls of
protected Caves with paint made from dirt or charcoal mixed with spit or animal fat In
Cave paintings the pigments (often carbon black or ochre) stick to the wall partially
because the pigment gets trapped in the porous wall and partially because the binding
media (the spit or fat) dries adhering the pigment to the wall Over the years countless
graves unearthed by archaeologists exposed bodies covered in red pigment or chunks of
pigment buried alongside the bodies Red associated with blood the most life sustaining
of body fluids was the appropriate color to symbolize lifes meaning and end The word
Hematite (the source of many iron oxide pigments) is derived from the Greek word hema
meaning blood (Chakarabarti 1980)
Wall paintings have been cultural expressions of human creation throughout
history from the earliest beginnings such as rock art extending up to present day murals
Throughout history humans have used the most beautiful and durable stones for
monumental buildings Beginning in the sixth century BC marbles extracted from the
Pentelikon quarry became a common building material Abundant limestone and marble
quarries enabled the ancient Greek architects to build the Acropolis and Roman architects
to build the Forum (Saiz 2002)
Figure-21 Cave painting
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
9 Review of Literature
Figure-22 Mural painting
The oldest known Maya murals are also the most recently discovered Murals
found at the Preclassic site of San Bartolo Guatemala date to 100 BC The church of San
Pietro and the ldquooratoriordquo of San Benedetto are believed by most scholars to date from the
third quarter of the 11th century During the last decade of the same century that some
changes were made to the edifice of the church and it was decorated with mural paintings
and stucco reliefs deep in the jungle of southeastern Mexico archaeologists were surprised
that the murals are about 1350 years old
St Agatharsquos Complex was one of the preferred sites since it consists of the
hypogean environment embellished by a significant number of wall paintings some dating
back to the fourth century AD The Catacombs of St Paulrsquos constitute a complex of
interconnected underground Roman cemeteries that were in use up to the 4th century AD
There are a few surviving murals and ochre inscriptions from late Roman and early
medieval periods Decorated tablets and reliefs adorn the graves (Zammit et al 2008) The
uncovering of paintings was made from the middle of the 19th century until the 1960s
23 Indian murals
History of wall paintings in India is studied through its evolution from Ajanta to
Kerala Ajanta paintings considered to have been executed between the 2nd
century BC and
5th
century AD Murals of 6th
century AD was found at Badami (Karnataka) and
Sittannavasal Jain cave temple (Tamilnadu) Murals of Narthamala Vijayalaya Chozeswara
belong to 9th
century AD and murals of Brihadeeswara temple Tanjore (Tamil Nadu)
belong to 11th
century AD Murals seen in Kerala are dated between 16th
17th and
19th
century AD (Sivaramamurthy 1994)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
10 Review of Literature
India has one of the greatest traditions of painting of the ancient world Murals and
miniature are the two different forms of arts which intrinsically related to Indian painting
tradition The earliest evidence of murals is the beautiful frescoes painted on the caves of
Ajanta and Ellora also on the Bagh caves and Sittanvasal The oldest mural paintings date
is about 3000 years BC (Sasibhooshan 2006)
The number of wall paintings in each state of India is very large and they are
suffering from all types of deterioration and damage but in comparison facilities for their
preservation are much too small This is a very serious problem The main objective of the
present study is to develop a protective bio-based gel (Rajagopalan 2008)
24 North Indian murals
North India has a rich heritage of Mural paintings even before the Mughal period
The murals at the Vishnu Temple located at Madanpur in Lalitpur district of Uttar Pradesh
of 12th century AD reveals the skillful hands of the painters In Eastern India there are
many evidences of wall and panel paintings describing Buddhist and non- Buddhist
themes In Arunachal Pradesh and Tripura sublime mural works have been found which
needs further study Ladakh is known for its wall paintings in Alchi and Hemis
monasteries made on 11th-12th century and the Spiti Vally in Himachal Pradesh is known
for its Buddhist paintings in the Gomphas of Tabo Monastery (Havell 1982)
Ajanta is known to be the fountain head and inspiration of Buddhist paintings
across the whole of Asia There are fragments of paintings of the time of Ajanta which
survive at many Buddhist cave sites including Pitalkhora near Ellora in Maharashtra The
magnificent Kailashnath temple had been hewn out of a mountain at Ellora in the 8th
centuryThe Kashmiri style was mainly responsible for the lovely wall paintings still seen
in the beautiful monasteries at Alchi Mangyu and Sumda in Ladakh in the Tabo
monastery in the Spiti valley and in the Nako monastery in Kinnaur district Himachal
Pradesh On the western edge of the trans-Himalayan plateau in Spiti is the monastery
complex of Tabo This appears to be one of the first among the 108 monasteries built by
Yeshe It is dated around 996 AD There are also paintings of the late 9th century in the
Jain caves at Ellora (Spink 2009)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
11 Review of Literature
Figure-23 Ajanta caves
Figure-24 Mural Painting of Ajanta caves
Ellora Caves Maharashtra belong to the highest achievements of mankind both
regarding the engineering skills and arts Some 2000 years ago Pitalkhora Caves
(Maharashtra) were among the largest temple complexes in India These 11 - 14 caves
were created in 250 BC - 4th century AD In 4th century AD temples were adorned with
beautiful murals especially fine paintings have been preserved on columns of Cave 3
Traces of murals are in Cave 6 as well Already the oldest group of caves here - Buddhist
caves from 630 - 700 AD - contain paintings of Buddhist panteon Remnants of paintings
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
12 Review of Literature
are seen in the most beautiful temple - Cave 16 Kailasanatha circa 760 - 860 AD Some
Jain temples - Cave 32 (Indra Sabha) Cave 33 - contain remnants of valuable murals from
800 - 1000 AD - this artwork marks the end of ancient period in the Indian art and
beginning of medieval art (Baskaran 1975)
Figure-25 Ellora caves
There are surviving mural paintings from the 17th century onwards in Rajasthan
The verdant Pahari hills saw the finest continuation of the tradition of murals in India The
18th and 19th century paintings on the walls of the Rang Mahal in Chamba are among the
best surviving examples of Pahari murals The 18th century paintings on the walls of the
Viranchinarayan Temple at Buguda are some of the finest surviving murals of that period
in India
Figure-26 Paintings on the walls of the Rang Mahal in Chamba
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
13 Review of Literature
The most important sites of rock paintings in North India are at Bimbetka Gwalior
Tikla Ayra Bhanpura Rampura Singhauli Bhojpur Adamgrh Delware and Mirzapur
In South India they are found at Mehaboob Nagar (Andhrapradesh) Edakkal Marayoor
Perimkadavila (Kerala) Mallampadi (Tamilnadu) and Bellary (Karnataka)These
paintings were considered as the early models of mural paintingsThe mural painting of
Sittannavasal Badami Lepakshi Tanjore Vijayanagar and Kerala has a lot of similarities
(Sasibhoosan 1987)
25 South Indian murals
South India also got rich tradition of mural paintings In the reign of Cholas
Vijayanagaras and Nayakas this art reached the climax The Deccan art of Bijapur
Hyderabad and Golconda schools were influenced by the Mughal traditions and later by
European idiom Maratha murals are also shaped under the Mughal traditions and
employed oil as medium The Mural art of Kerala vividly depicted on the walls of temples
and monuments show the traces of European affinity In Tamil Nadu almost all the extent
examples of frescos have been done on rock surfaces and stone walls This is a crucial
factor in determining the quality of frescos (Havell 1982) The ceiling of the Virupaksha
temple in Hampi is covered with paintings of the 15th century The paintings on the ceiling
of the mandapa of Lepakshi temple are some of the finest mural paintings of the medieval
period in India Legends associated with Siva and Parvati Krishna and Rama were painted
on the walls of palaces and temples in Kerala from the 16th to 19th century Mural
paintings were made on the walls of all the palaces within the magnificent Orccha fort The
Raj Mahal was completely adorned with mural paintings of the 17th century
Figure-27 Virupaksha temple in Hampi
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
14 Review of Literature
Figure-28 Ceilings of Virupaksha temple Hampi
The murals on the walls of the navaranga (the central pillared hall) depict stories
from Bhagavatha and are excellent examples of 19th
century Mysore paintings The
Mallikarjunaswamy temple on the hill is one of the Panchalingas of Talakad and the
temple has a beautiful mural painting on the wall of the temple The Dariya Daulat Bagh
has excellent mural painting (Sasibhoosan 1987)
Figure-29 Paintings on the walls of Jagan mohan palace Mysore
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
15 Review of Literature
Figure-210 Painting of Raja woodeyar era
Kerala mural paintings are the frescos depicting mythology and legends which are
drawn on the walls of temples and churches in South India principally in Kerala Ancient
temples churches and palaces in Kerala South India display an abounding tradition of
mural paintings mostly dating back between the 9th to 12th centuries The murals of
Thirunadhikkara Cave Temple (now ceded to Tamilnadu) and Tiruvanchikulam are
considered the oldest relics of Keralarsquos own style of murals Fine mural paintings are
depicted in temples at Trikodithanam Ettumanur Vaikom Pundarikapuram
Udayanapuram Triprangode Guruvayoor Kumaranalloor Aymanam the Vadakkunathan
temple in Trichur and the Sri Padmanabhaswamy temple at Thiruvananthapuram Other
mural sites are in the churches at Edappally Vechur Cheppad and Mulanthuruthy and at
palaces such as the Krishnapuram Palace near Kayamkulam and the Padmanabhapuram
Palace
Figure-211 Kerala murals
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
16 Review of Literature
Figure-212 Murals paintings of Kerala temples
There are wall paintings in Badami in the Bijapur district Karnataka Some
excellent paintings exist in the Jain caves at Sitanavassal in Puddukkottai District of Tamil
Nadu Tamil Nadu gave exuberant and glorious expression to themes relating to Siva in the
temples of Panamalai and Kailashanatar in Kancheepuram In the 9th century Jain cave of
Sittannavasal in Tamil Nadu there is a marvellous lotus pond painted on the ceiling In
the heart of the Brihadeeswara temple in Thanjavur Tamil Nadu protected by massive
walls of stone are the finest paintings of the theme of Siva ever painted towards the end of
the 10th century (Sivaramamurthi 1992)
Figure-213 Kancheepuram Mural paintings
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
17 Review of Literature
Figure-214 Sculpture of Mahabalipuram
26 Methods of mural painting
In the history of mural several methods have been used The Buon fresco technique
consists of painting in pigment mixed with water on a thin layer of wet fresh lime mortar
or plaster The pigment is then absorbed by the wet plaster after a number of hours the
plaster dries and reacts with the air it is this chemical reaction which fixes the pigment
particles in the plaster After this the painting stays for a long time up to centuries in fresh
and brilliant colors A Secco painting is done on dry plaster The pigments thus require a
binding medium such as egg (tempera) glue or oil to attach the pigment to the wall
Mezzo-fresco is painted on nearly-dry plaster which is defined by the sixteenth-century
author Ignazio Pozzo as ldquofirm enough not to take a thumb-printrdquo so that the pigment only
penetrates slightly into the plaster Ancestral Hopi village archaeologists found that
fourteen kivas had painted murals and multiple layers of murals on the walls some with up
to twenty-seven layers of murals (Saturno 2006)
The colors used in painting are generally obtained from plants and minerals
Among them only such colors which are lime resistant are suitable for mural painting The
selection of proper colors for a mural painting is an important part of the work as the
longevity the painting depends on it Only mineral colors are preserved for a long time
which could be the reason for use of those colors in early days As per ldquoShilpa ratnardquo and
ldquoAgnipuranardquo the colors used in mural painting are white black red yellow blue and
green Yellow and red are from yellow ochre and red ochre Blue is generally indigo or
china blue White is the prepared wall and black is the carbon soot Mural paintings have
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
18 Review of Literature
survived centuries only on account of the identification and use of those colors which does
not have any reaction with lime (Miraseth 2006)
Originally three types of brushes were made and used flat medium and fine Flat
brushes were made from hairs behind calfrsquos ear the medium from the bottom of goats
belly and the fine brush from delicate blades of grass However in due course of time and
change use of easily available brushes from commercial market and shading of the
original colours can be distinctively noticed The use of blue colour is also noticed over the
passage of time The paintings have been brought down from the walls to plywood cloth
paper and other frames for easy to make and use purposes (Chakarabarti 1980)
27 Themes of mural painting
The subjects and themes in the murals are centered on the Hindu pantheon of Gods
and Goddesses drawn from description in the invocatory verses or Dhyana Slokas More
common representations are of Vishnu in different incarnations Ganesha and
manifestations of Siva We see murals in the Pallimanna Siva Temple devoted to Siva-
Parvatirsquos marriage the Ramayana Story being narrated on the walls of the Mattancheri
palace in the Sankara Narayana the Mahabharata is retold Murals are various scenes from
the Hindu epics and also the frolics of Lord Krishna
It would be interesting to bring into account the influence of the mural paintings on
Christianity On various churches like the St Georgersquos Orthodox Church has Christian
murals bringing out biblical characters and narrating stories from the scriptures Mar
Sabore and Afroth Church at Akapparambu in the outskirts of Ernakulam also have murals
of scenes from the bible Interestingly StMaryrsquos Church at Kanjoor has on both sides of its
entrance a battle scene between the armies of Tipu Sultan and of the English East India
Company It is also apparent that the history of Kerala Murals has its origin in the temple
walls and thus a study of Kerala Murals is not complete without pondering on the
architecture of Kerala its association with the murals (Warrier 2011)
28 Technique used in mural paintings
Indian murals executed on walls of caves structural temples walls of palaces were
based on highly developed techniques Mural painting is a composite structure of these
three basic layers the support the ground and the pigment layer In case of wall painting
the wall itself is the support This is followed by the layer or layers of plaster which
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
19 Review of Literature
constitute the ground The pigment layer is the one which contains the picture The support
is the wall which may be rock surface in a cave or a structural one These stone surfaces
which serve as carriers are rough or uneven This unevenness is itself an advantage as it
provides ldquotoothrdquo to hold the plaster on the surface The uneven surface of the wall has to be
made uniform with layers of plaster in successive gradation of fineness There is generally
one layer of rough plaster followed by one or more layers of fine plaster Ground or plaster
is a term used to mean the surface material of a wall or building which is applied as a
plastic mass made by mixing certain materials with water letting the mass set by drying
carbonation or hydration The active or setting components of plaster are commonly clay
which sets by drying lime which sets by carbonation gypsum and pozzolana which sets by
hydration (Mini 2010)
There are different mixtures for rough plaster In all the mixtures clay limestone
lime and shells in powdered form serve as the matrix The particles of which are held
together by the organic materials like gum glue extracts from barks etc are in fact
adhesives The fine plaster layer requires more careful preparation because it is the layer on
which the pigments are laid to make the picture ldquoShilparatnardquo suggest a mixture of conch
Oyster shells or white clay with gum of neem or slaked lime and coconut water Here the
consolidation is effected by the carbonation of slaked lime ie it absorbs carbon dioxide
from air and becomes carbonate Mural paintings were lime-washed from the 17th until the
beginning of 19th century A few paintings in vaults were never lime-washed for example
at Taby and Floda painted by the medieval painter Albertus Pictor (Mini 2010)
All the paintings have certain basic common characteristics There has to be a wall
or rock surface called support over which the artist goes to work A plaster base called
ground of varied thickness is laid on the support The ground may consist of one or more
layers The strength and life of the whole mural depended up on this ground over which the
painting was done It is the process of applying the final painting on the ground determines
the character of the mural whether it is fresco or tempera The mural painting is done
usually by creating wall surface free of any previous oil or paint by using solvent or by
sand blasting The brick wall is first plastered with mixture of lime and sand in the ratio of
12 A mixture of egg yolk vinegar oil colour is used in dry plaster
There are at least six stages before a Kerala Mural Painting is complete Lekhya
Karma is the first stage where sketching by pencil or crayon is done The second stage is
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
20 Review of Literature
the Rekha Karma which enhances the outlines of the sketching done The third stage called
Varna Karma breathes life into the painting with its colours Here all colours are
appropriately filled in The colouring of the human figures is done according to the
characters and their common virtues The divine and noble characters (Saatvik) are painted
in green those inclined towards power and wealth (Raajasik) is painted in shades of red
lowly mean characters (Tamasik) in white and demons in black In the fourth stage or the
Vartana Karma shading is done Fifth stage called the Lekha Karma brings us to the final
outline of the painting which is usually in black The final and the finishing touches stage
are called Devika Karma (Warrier 2011)
29 Dyes used in mural painting
Indians have been considered as fore runners in the art of natural dyeing Natural
dyes find use in the colouring of textiles drugs cosmetics etc Owing to their non-toxic
effects they are also used for colouring various food products In India there are more
than 450 plants that can yield dyes In addition to their dye-yielding characteristics some
of these plants also possess medicinal value Though there is a large plant resource base
little has been exploited so far Due to lack of availability of precise technical knowledge
on the extracting and dyeing technique it has not commercially succeeded like the
synthetic dyes (Siva 2007)
The color materials on the mural paintings in ancient India were derived from the
natural materials like terracotta chalk red ochre and yellow ochre mixed with animal fat
The dyes for painting is prepared such as white from lime Black from carbon soot of
lamps Red and yellow from minerals Blue from indigo ferra Deep red from lac A fine
coating of resin is done after the painting in order to make a shining appearance Egg yolk
and vinegar was mixed with oil colors and painted on dry plaster (Krishnakumar 1999)
Although plants exhibit a wide range of colours not all of these pigments can be
used as dyes Some do not dissolve in water some cannot be adsorbed onto fibres whereas
others fade when washed or exposed to air or sunlight It remains a mystery why plants
reward us with vibrant dyes India has a rich biodiversity and it is not only one of the
worldrsquos twelve mega diversity countries but also one of the eight major centres of origin
and diversification of domesticated taxa It has approximately 490000 plant species of
which about 17500 are angiosperms more than 400 are domesticated crop species and
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
21 Review of Literature
almost an equal number their wild relatives Thus India harbours a wealth of useful
germplasm resources and there is no doubt that the plant kingdom is a treasure-house of
diverse natural products One such product from nature is the dye (Siva 2007)
Many natural dyestuff and stains were obtained mainly from plants and dominated
as sources of natural dyes producing different colours like red yellow blue black brown
and a combination of these Almost all parts of the plants like root bark leaf fruit wood
seed flower etc produce dyes It is interesting to note that over 2000 pigments are
synthesized by various parts of plants of which only about 150 have been commercially
exploited Nearly 450 taxa are known to yield dyes in India alone of which 50 are
considered to be the most important ten of these are from roots four from barks five from
leaves seven from flowers seven from fruits three from seeds eight from wood and three
from gums and resins Some important dye-yielding plant habitats their distribution and
colouring pigment (Siva 2007)
The dye is generally prepared by boiling the crushed powder with water but
sometimes it is left to steep in cold water The solution then obtained is used generally to
dye coarse cotton fabrics Alum is generally used as a mordant Flowers of Butea
monosperma (Lam) Taubert yield an orange-coloured dye which is not fast and is easily
washed away For the purpose of colouring the material is steeped in a hot or cold
decoction of the flowers A more permanent colour is produced either by first preparing the
cloth with alum and wood ash or by adding these substances to the dye-bath The dye
indigo is produced by steeping the plant in water and allowing it to ferment This is
followed by oxidation of the solution with air in a separate vessel Mallotus philippinensis
muell yields an orange colour used for dyeing silk and wool To prepare the annatto dye
from B orellena the fruits are collected when nearly ripe The seeds and pulp are removed
from the mature fruit and macerated with water Thereafter they are either ground up into
an lsquoannatto pastersquo or dried and marketed as annatto seeds Sometimes when the seeds and
pulp are macerated with water the product is stained through a sieve and the colouring
matter which settles out is collected and partially evaporated by heat and finally dried in
the sun (Sowbhagya 2002)
The predominant colors used in rock art and cave art are black (from charcoal soot
or manganese oxide) yellow ochre (limonite) red ochre (hematite or baked limonite) and
white (kaolin clay burnt shells powdered gypsum or powdered calcium carbonate) All of
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
22 Review of Literature
theses pigments may be used on leather or raw hide as well Early cave art in Seminole
Canyon was monochromatic in red and as culture grew more sophisticated the color
palette expanded Blue Orange Brown Green and Purple are the most common colours
used in Ajantha murals White Pink Gold are occasionally represented mineral earths
containing ferric oxide and copper carbonates were used as source of red yellow and green
colours There is also evidence to establish that root of Rubia cardifolia and leaves of
Indigofera tinctoria were used as source for red and blue colours (Nayer et al 1999)
Many colors of pigments were obtained from both organic and inorganic sources in
ancient times and used to paint various surfaces such as braintan leather clothing and
accoutrements rawhide the human body etc Blue color was obtained from powdered
azurite and lapis duck manure and certain clays Fine Blue-green clay was obtained from
deposits near Mankato Michigan Organic sources of blue include Turkeys Tail a
greenish blue polypore that grows on dead decaying wood (not tannish ones) Native
Americans get Indigo from either Guatemala or Ecuador which was traded well up onto
Kansas long before the Spanish ever set foot here American Indigo has purple tones to it
but IndianJapanese indigo has green tones Berries and crushed flowers were also used to
obtain blue color by rubbing the plant material directly on the leather
An organic source of red was Cochineal It was native west of the Mississippi and
is produced from the bodies of small insects that grow on the prickly pear cactus Ladys
Bedstraw gives a good vermillion red color Harvest the roots dry them out clean the mud
etc off of them and then grind the roots really fine then soak them to extract the red
coloring The key here is drying the root first Blood was also used as red pigment Pucoon
roots also yield a red pigment (Smith 2002) Red ochre the reverse original red colours are
due to variations in iron oxide (or) calcite content and to redox conditions in the firing
produced Brown coloured ceramics owe their colour to maghemite and must be
considered as a fabrication defect due to the position of the ceramic piece in a zone where a
reducing atmosphere prevailed in the course of firingRed pigments were produced from
iron oxides like hematite or limonite and from ochre Hematite was the most frequently
used mineral It occurs in the form of aggregates of small red crystals or in the form of
bigger black crystals which are difficult to crush white was obtained mostly from
kaolinite or illite (Clottes et al 1990)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
23 Review of Literature
210 Biodetoriation of mural paintings
Historic items often contain natural biodegradable materials and have histories of
exposure to moist conditions These two conditions make them amenable to microbial
attack Microbial colonization may damage the building or the cultural asset
(Salonen 2001) Biodeteriogens are organisms involved in deterioration of artifacts They
are very specific for each type of artifact in accordance with its chemical structure and
environment They also have different nutritional requirements and act directly or
indirectly on the substrate The adhesion of microorganisms to a substrate is the result of
cell hydrophobicity and of excreted polymeric substances contained by sheaths capsules
and slimes (Colao 2005)
The surviving wall paintings and decorations in subterranean environments around
Malta are rather scarce (Buhagiar 1986 1993 1998) These include those at St Paulrsquos
Catacombs (Zammit 2008) St Agatharsquos Crypt and Catacombs (Camilleri 2001)
San Catald Catacombs Tac-Cghaqi Abbatija tad-Dejr (Buhagiar 1993) all in Rabat the
cave-sanctuary in Mellieħa (Buhagiar 1987) and the Ħal Saflieni Hypogeum in Paola
(Pace 2000) Previous studies conducted on wall paintings and decorations in Maltese
Palaeo-Christian Catacombs have involved their manufacturing techniques (Muscat 2005)
However to date limited systematic studies have been conducted into the biodeterioration
in Maltese Palaeo- Christian Catacombs The only such studies ever conducted in Malta
concerned the biodeterioration of works of art in catacombs have been carried out at St
Agatharsquos Crypt and Catacombs in Rabat (Zammit et al 2008 Psaila 2006)
Microorganisms can be responsible for the destruction of monuments buildings
and cultural heritage assets including the decay of concrete cement stones mural
paintings etc These microorganisms are not only related with biodeterioration but water-
damaged indoor building materials are frequently colonized by complex bacterial
communities and may emit mixed bioaerosols into the indoor air (Jimenez 2000) It is
well known that mural paintings are colonized by micro-organisms and can be severely
damaged by such growths (Ciferri 1999) A large number of fungal (gt50) and bacterial
taxa (70) have been detected in indoor environments Over 50 bacterial species and 14
genera novel to science were reported in the past 10 years from indoor air and historic
items indicating bacterigravea in these enviroments are as yet only fragmentarily known
(Salonen 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
24 Review of Literature
Traditionally the study of microflora which causes this biodeterioration was based
on classical cultivation methods that were mainly useful to study the physiological
potential of microorganisms but do not provide information on all microbial communities
to be found in excavated artifacts Indeed many studies using culture-independent
techniques which cultivate microorganisms from different environments may often
represent only minor components of the microbial community as a whole It is generally
accepted that cultivation methods recover less than 1 of the total microorganisms present
in environmental samples (Ward et al 1990 Amann et al 1995) Hence microbial
investigations based only on cultivation strategies cannot be regarded as reliable in terms
of reflecting the microbial diversity present in objects of art (Osburn et al 2011)
Early workers suggested that the presence of living microorganisms on stone
increased its susceptibility to damage through their water-binding capacity It has recently
been reported that the mineralogy porosity surface roughness and capacity to collect
water and organic materials control its bioreceptivity and tendency to biodeterioration
(Diakumaku 1995) In addition environmental factors as temperature light pH and
relative humidity affect the number and type of colonising species (Tiano et al 1995) and
hence the progress of colonisation Biofilms on decayed stones consist on mixed microbial
populations embedded in a polymeric matrix Fungi algae filamentous and unicellular
bacteria are found in these complex communities A variety of bacteria have been isolated
from different stone samples confirming the dominance of Gram-positive organisms
especially spore-forming bacteria such as Bacillus and filamentous actinomycetes
(Ripka 2005)
In cultivation studies of deteriorated mural and rock paintings bacterial isolates
have frequently been attributed to the genus Bacillus (Weirich 1989 Tate and Rebrikova
1991 Gonzalez et al 1999 Heyrman et al 1999 Jimenez et al 2000) Other studies that
have included DNA-based techniques to characterize the bacterial community involved in
biodeterioration have shown that a substantial part of the bacterial population is made up of
so far unknown species (Altenburger et al 1996 Rolleke et al 1996 Gurtner et al 2000
Heyrman and Swings 2001) (Heymann et al 2003)
Many potential mycotoxin producers have been detected in air and items from
indoor environments with histories of exposure to moisture for example species of
Acremonium Alternaria Aspergillus Chateomium Fusarium Eurotium Paecilomyces
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
25 Review of Literature
Penicillium Scopulariopsis Stachybotrys Trichoderma Verticillium and Wallemia
(Peltola et al 2001 Pieckova et al 2001) Not all strains of one species produce
mycotoxins and different strains may produce different toxins Whereas toxin producing
strains are frequent in crops and outdoor vegetation toxin producing isolates from indoor
environments and non living assets have only been reported of the species Aspergillus
versicolor (Nielsen et al 1998) Stachybotrys chartarum Nikulin (1997) and
Trichoderma harzianum (Peltola et al 2001) Streptomyces griseus strains producing
valinomycin occur in environments where humans can get exposed
(Andersson et al 2002) The biological properties and toxicity mechanisms of cereulide
were identical to those by valinomycin (Mikkola et al 1999 Salonen et al 2001)
The genus Paenibacillus was first proposed by Ash et al (1993) and its description
was emended by Shida et al (1997) The genus Paenibacillus is under intensive taxonomic
investigation with ten species having been formally described in the last year Heyrman amp
Swings (2001) isolated a strain originally classified as Paenibacillus sp LMG 19508
from biodeteriorated mural paintings in the Servilia tomb at the Roman necropolis of
Carmona in Seville Spain (Smerda et al 2006) Building stone and wall paintings contain
a variety of hydroscopic salts including carbonates chlorides nitrates sulfates etc
dispersed within the porous material or locally concentrated These salts are solubilised
and migrate with the water in and out of the stone Due to changes in physical parameters
the so called salt efflorescences appear on the surfaces providing extremely saline
environments and building niches for settlement of halophilic microorganisms Halite and
other hygroscopic salts can retain considerable quantities of moisture when entrapped in
the building materials and thus favouring the bacterial growth (Ripka 2005)
It is demonstrated that water-damaged indoor building materials contained
substances of microbial origin extremely toxic to eukaryotic cells and large quantities of
several microbial species known to be potentially toxic or immunopotentiating These
include peptidoglycans Gram-negative endotoxin β-13-D glucans lipoglycans and
teichoic acids and mycotoxins (Jimenez 2000) In turn these microorganisms can mediate
the crystallization process These crystallizations can produce destructive effects Some
salts may crystallize or recrystallize to different hydrates which occupy a larger space and
exert additional pressure producing cracking powdering and flaking
(Jimenez and Laiz 2000)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
26 Review of Literature
211 Types of deterioration on mural paintings
The frescos represent a variety of ecological niches where primary colonization is
due to photoautotrophic and chemolithoautotrophic microorganisms followed by
secondary colonization due to heterotrophic bacteria that obtain nutrients from various
sources (metabolites of autotrophic bacteria airborne organic contamination animal faeces
and organic compounds in the paint layers themselves) Microbial-induced deterioration
processes cause structural as well as aesthetic damage to wall paintings such as the
discoloration of materials the formation of crusts on surfaces and the loss of material
(Sarro et al 2006 Osburn et al 2011) Halophilic bacteria and archaea were thought to
be found only in extreme environments like salt lakes or black smokers However it has
been shown that mural paintings and stones are a common habitat for extremely salt
tolerant and moderate halophilic (Ripka 2005) Microbial induced deterioration processes
can cause different kinds of alterations such as discolouration of materials the formation of
crusts on surfaces and the loss of material which leads to structural damage (Ripka 2005)
First of all microorganisms can cause severe problems due to the excretion of aggressive
metabolic products such as organic or inorganic acids Secondly material components can
be used as substrates for microbial metabolism Exoenzymes such as cellulases proteases
tannases beta-glucosidase produced by fungi and bacteria are responsible for hydrolysis of
cellulose and proteins Further examples are mechanical processes caused by swelling and
shrinking of slime or mycelia penetrating inside plaster of the painting resulting in loss of
cohesion and detachment of the paint layer (Rolleke 1996 Gurtner et al 2000)
Table-21 Microbial damage on mural paintings (Rolleke 1996)
S No Damage Microbial activity
1 Green brown red grey
surface layers (patinas)
Pigments produced by microorganisms (intra-or
extracellular) as chlorophyll and carotinoids
2 Dislodging of painting layers Use of organic binders as nutrient and energy
source
3 Acid attack of carbonates Acid produced by fungi or bacteria
4 Discolouration of pigments Redox-reactions induced by fungi and
bacteria
5 Loss of paint layer Growth of microorganisms deep into the plaster
6 Hydrolysis of synthetic
polymers Chemoorganotrophic activity of bacteria and fungi
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
27 Review of Literature
Discolorations are caused by excretion of pigments and microbiologically induced
reductionoxidation-processes (Krumbein et al 1990) Degradation of the bindings is
followed by reduction of stability Oxidation of ammonium and reduced sulphur
compounds results in acidification of the environment such as Sulphuric acid and the
variety of organic acids produced by the heterotrophs cause solubilization of calcareous
binding material and chelation of metal ions (Bock et al 1993) It is now well recognised
that wall paintings can be deteriorated by microorganisms (Ciferri 1999)The growth of
microorganisms essentially results in two types of damage aesthetic and structural
Aesthetic damage implies pigment discoloration stains and formation of a biofilm on the
painted surface Structural damage is observed as cracking and disintegration of the paint
layer formation of paint blisters and degradation of support polymers or of glues and
binders resulting in detachment of paint layer from the support The colonization of mural
paintings by bacteria and other microorganisms can have different causes Provided that
favorable environmental conditions occur nutrients for heterotrophic bacteria and fungi
can be available from metabolites of autotrophic bacteria from airborne contamination and
dripping water from animal faeces but also from organic compounds in the paint layer
itself
212 Methods of studying biodeterioration
It is now well recognized that wall paintings may be deteriorated by
microorganisms as established by several studies that linked the observed damage with the
microbial community present as reviewed by Ciferri (1999) Despite this knowledge a
reliable characterization of bacteria associated with such damage is often lacking To
obtain greater insight into the bacterial community involved in biodeterioration of mural
paintings three sites (from the necropolis at Carmona Spain and the Saint-Catherine
chapel of the castle at Herberstein Austria) were sampled In previous studies from these
sites 385 isolates were analysed by fatty acid methyl ester GC and representatives of
different fatty acid clusters were further studied by 16S rRNA gene sequencing
(Heyrman and Swings 2001) Several of these representative strains showed the highest
sequence similarity with members of the genus Arthrobacter (Heyrman et al 2005)
Jimenez and Samson (1981) analysed the microbial flora of a large fresco painted
in the late 1920s in the monastery ldquoSanta Maria de la Rabidardquo (Huelva Spain) exhibiting
two types of deterioration white efflorescence and green-to-black stains
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
28 Review of Literature
Tate and Rebrikova (1990) thought autotrophic nitrifying bacteria to be the first colonisers
of damaged frescoes and building materials in the cathedral of the nativity of the Virgin in
the Pafnutii-Borovskii monastery (Russia) The bulk of research on biodeterioration of
mural paintings has focused on explaining the observed phenomena by analysing the
microflora present Following this approach a precise characterisation of the
microorganisms using a polyphasic approach was never the first goal
Only a few studies included genomic fingerprinting (16S rDNA sequence analysis)
for the characterisation of bacteria associated with damage on mural paintings
[Rolleke (1996) Pinar et al (2001)] Previous studies based on culture-dependent
techniques showed that the flora present on frescos are fungi (predominant species of
Penicillium Aspergillus Cladosporium and Engyodontium) (Guglielminetti et al 1994)
bacteria (predominant species of Bacillus Arthrobacter Micrococcus Streptomyces and
Pseudomonas) (Heyrman et al 1999) cyanobacteria and eukaryotic algae (species of
Nostoc Lyngbya and Chlorophyceae) (Arino et al 1996 Calvo et al 1993) The killing
effect of an antimicrobial agent on a microorganism can be assessed in several ways
(1) Lethal activity may be expressed as the rate of killing by a fixed concentration
of drug under controlled conditions This rate is determined by measuring the number of
viable bacteria at various time intervals The resulting graphic depiction is known as the
time-kill curve Bacterial killing rates are in part dependent on the class of antibiotic and
the concentration of this agent With certain classes of antibiotics (eg aminoglycosides
and fluoroquino-lones) the rate of killing increases with increased drug concentrations up
to a point of maximum effect This is termed concentration-dependent bactericidal activity
In contrast the killing rates of szlig-lactam agents and vancomycin are relatively slow and
continue only as long as the concentrations are in excess of the MIC This rate of killing is
termed time-dependent bactericidal activity
(2) The minimal concentration of drug needed to kill most of the viable organisms
after incubation for a fixed length of time (generally 24 hours) under a given set of
conditions is the most common estimation of bactericidal activity and is known as either
the minimal bactericidal concentration (MBC) or the minimal lethal concentration (MLC)
It will be referred to in this document as the MBC Unfortunately the definition of the
MBC (999 killing of the final inoculum) is somewhat arbitrary and separates the
bacteria into two populations ndash a segrega-tion which might not have biological relevance
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
29 Review of Literature
The determination of the MBC moreover is so subject to methodologic variables that the
clinical relevance of MBCs is nearly impossible to assess particularly for certain pathogen
and drug combinations (eg Staphylococci and beta-lactam agents)
(3) The serum of a patient receiving an antibiotic may be tested against the
infecting microorganism This can be done using time-kill curve methodology (ie serum
bactericidal rate) or using dilution methodology (ie serum bactericidal titer) The
principles of these methods as well as the influence of biological and technical factors are
similar (Barry et al 1999)
213 Microbial flora associated with deteriorated mural paintings
A great deal of research has been done in this field mainly by using cultivation dependent
methods However by using culture-dependent methods only a very small proportion of
microorganisms can be obtained Far less than 1 of organisms in the environment can be
cultivated by standard cultivation techniques (Pace 1996) Recent studies have shown that
culture-dependent techniques yielded mainly sporeforming bacteria suggesting that plating
leads to an over estimation of the number of spore-forming bacteria A wide number of
investigations have shown that in addition to chemical and physical processes
microorganisms play a major role in degradation of objects of art such as paintings stone-
works wood paper masonry leather parchment glass and metal (Ripka 2005)
A) Bacteria
In general growth of diverse organisms on mural paintings is supported by
humidity slight alkaline pH values and the presence of organic and inorganic nutrient
sources (Weirich 1989) In mural paintings pigments are suspended in water or oil often
binders such as casein and milk are used and they are supplied on the damp lime plaster
(Ciferri 1999) The calcium carbonate formed on contact with air consolidates the
pigments Thus frescos contain mainly inorganic components While chemoautotrophic
nitrifiers and thiobacilli obtain their energy for growth by oxidizing ammonium and
reducing sulphur-compounds respectively heterotrophic bacteria and fungi depend on
organically bound carbon [Tate et al (1991) Lazar (1971) Petushkova et al (1986)
Jimenez et al (1981)] Thus primary colonization of photoautotrophic Cyanobacteria
chemolithoautotrophic nitrifying bacteria and sulphuric acid producing thiobacilli represent
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
30 Review of Literature
the first supply of organic matter The death and lysis of such bacteria promotes the
secondary settlement of heterotrophic bacteria and fungal populations (Calvo et al 1991)
Bacteria may derive from plants or pollen as many sequences obtained in this study
gave high score similarities with bacteria isolated from plants like Moraxella osloensis
Enterobacter cloace Enterobacter agglomerans and Pantoea endophytica Bacteria may
also derive from animal faeces like flies Bacillus Pseudomonas Aeromonas and Panteoa
(Ripka 2005) As Lazar and Dumitru (1973) reported studying mural paintings in a
Romanian monastery the genera Bacillus Arthrobacter and Pseudomonas have been
proved to produce salt efflorescences and were even considered to cause the blanching
phenomenon of frescoes (Jimenez et al 2000) Predominant bacterial genera are Bacillus
Streptomyces Arthrobacter Micrococcus and Pseudomonas [Weirich (1989)
Tate et al (1990) Arroyo et al (1997) Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
B) Fungi
It may be concluded that there is wide variety of fungal forms present on mural
paintings but Aspergillus and Alternaria were found dominating from all the experimental
sites next to them were Cladosporium Drechestera Fusarium Curvularia Chaetomium
Memnoniella Mycelia sterelai Pencillium Emericella Stachybotrytis Trichoderma
Phoma Monodictys Humicola and Epicoccum (Garg et al 1995)
The fungal genera most commonly found in lists of isolated taxa given in literature
are Alternaria Aspergillus Chaetomium Cladosporium Fusarium Penicillium and
Verticullum [Weirich (1989) Tate et al (1990) Guglielminetti et al (1994)
Garg et al (1995) Berner et al (1997) Ciferri (1999)] Some fungi having hard fruiting
bodies represented by sclerotia pycnidia perithecia cleistothecia and stroma could
organize themselves inside the painted layer Many fungal forms having such structures
were identified from our experimental sites viz Emericella nidulans A flavus
Chaetomium sp and Phoma sp etc These structures with little increase in humidity may
cause swelling in the paint film (Garg 1995)
Strains of species of Alternaria and Cladosporium both of them identified on the
mural paintings of the Palace of Schoumlnbrunn are the most common genera isolated from
stone and mural paintings in indoor environments with standard cultivation methods
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
31 Review of Literature
(Ventosa 2004) Saprophytic species of the genus Cladosporium are among the most
abundant fungi isolated in saltern samples Commonly isolated Cyanobacteria belong to
Nostoc and eukaryotic algae to Lyngbya and members of the Chlorophyceae such as
Chlorella Pseudococcomyxa and Pseudopleurococcus [Gorbushina et al (1987)
Calvo et al (1993) Arino et al (1996)]
They grow optimally on media with low water activity due to high salt or sugar
concentrations seem to propagate 70 vegetatively in the salterns and are thus
halotolerantosmotolerant species rather than simple flush-through occurrences
Cladiosporum herbarum was frequently isolated from hypersaline waters dead and dying
plant material air soil food fruit cereals paint and textiles (Ventosa 2004)
C) Algae
Most of the painted areas in temperature climate became covered with green algae
(Pleurococcus Protococcus and Trentopholia) while under tropical conditions blue green
algae of the genera Oscillatoria and Sytonema predominated (Garg 1995) The main
factors which contribute to the growth of algae on wall paintings are the presence of
moisture in the plaster as well as availability of visible light These conditions are quite
prevalent in the tropical climate but in temperature regions also algal growth on wall
paintings have been reported [Tonolo et al (1961) Pietrini et al (1991)]
D) Actinomycetes
Usually literature refers to specific aspects eg the occurrence of cyanobacteria
and algae in caves with natural openings to sunlight or those with artificial lighting fungi
and so forth Actinomycetes have been considered to be mainly confined to soils where
they find their natural habitat but despite intensive studies there are still many gaps in our
knowledge of the role played by actinomycetes in soil processes and biodegrations of
murals cave paintings (Groth et al 1999) In addition halophilic bacteria actinomycetes
and cyanobacteria are also capable of growing on salt-affected mural paintings
(Karbowska 2003)
Monte and Ferrari (1993) reviewed the mechanisms of biodeterioration in tombs
and underground churches The role of actinomycetes in the deterioration of frescoes in
hypogean environments was stressed by Agarossi et al (1985) Monte and Ferrari (1993)
Giacobini et al (1987) described the serious damage suffered by a whole series of famous
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
32 Review of Literature
frescoes in underground environments Actinomycetes were isolated from these mural
paintings located in crypts caves and tombs About 200 strains of actinomycetes were
isolated 60 of which were identified The most frequent species were Streptomyces albus
S cinereoruber S griseolus S vinaceus and some members of the Nocardia genus
Heterotrophic bacteria and actinomycetes were the most abundant microorganisms
on the frescoes of Etruscan tombs (Agarossi et al 1985) Bettini et al (1977) studied
some of the oldest Etruscan tombs (7th to 4th century BC) and found white-grey patinas
and spots from streptomycetes in the mural paintings They related the biodeterioration to
the microclimatic conditions (eg lower temperatures high RH) Monte and Ferrari (1993)
considered that colonization of the mural paintings was the result of selective competitive
and inhibitory dynamics among different microorganisms under different and changing
environmental conditions The pigments excreted by some actinomycetes were responsible
for the violet stains found on the walls of tombs in Tarquinia Similar stains were observed
in one of the Roman tombs the Circular Mausoleum the Necropolis of Carmona Spain
from which a Streptomyces sp producing violet pigments in culture media was isolated
214 Identification of biodeteriogens
The possibility of pigments and biodeteriogens identification in frescos and stone
monitoring is offered mostly by vibrational spectroscopy infrared thermography laser
induced fluorescence (LIF) laser induced breakdown spectroscopy (LIBS) XRF (X-Ray
Fluorescence) IR and UV emission Among them laser based methods allowing for in
situ or remote characterization of artwork surface were applied successfully for
prospecting diagnosis and maintenance (Colao et al 2005) The rep-PCR fingerprinting
of the isolates allowed determination of their genotypic diversity Studies that have
compared rep-PCR genomic fingerprint analysis with DNAndashDNA relatedness studies have
shown that the two techniques yield results that are in close agreement [Nick et al (1999)
Rademaker et al (2000)] These studies therefore suggest that rep-PCR fingerprinting can
be used as a genomic screening method to differentiate at the species level and to select
representatives for DNAndashDNA reassociation experiments (Heymann et al 2003)
The characterisation of bacteria was for example often limited to isolation from
group-specific media followed by microscopy [Sorlini et al (1987) Weirich (1989)
Tate et al (1990) and in more recent studies to morphological and physiological
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
33 Review of Literature
characteristics including miniaturised and automated systems such as API and BIOLOG
[Arroyo et al (1997) Jimmenez et al (2000) and Laiz et al (2000)] or to
chemotaxonomic characteristics [Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
Wagner et al (1994) demonstrated that conventional microbiological efforts can
fail to isolate all microorganisms present in natural samples DNA-based techniques used
to identify microorganisms have revealed only a smaller fraction of bacteria isolated from
artworks (Ward et al 1990 Rolleke et al 1996) Bacterial identification using molecular
techniques especially those including the sequencing of genes coding for ribosomal
16S rRNA is very important to study bacterial communities found on artefacts One such
method is Denaturing Gradient Gel Electrophoresis (DGGE) of PCR-amplified gene
fragments coding for rRNA (Muyzer et al 1993) that allows the separation of partial
16S rDNA amplified fragments of identical length but different sequence due to their
different melting behaviour in a gel system containing a gradient of denaturants
(Jimenez 2003)
Total genomic DNA was purified for 16S rRNA gene sequencing and rep-PCR
using a slight modification of the method of Pitcher et al (1989) as described by
Heyndrickx et al (1996) rep-PCR genomic fingerprinting was performed with the REP-
and (GTG)5 primers (Versalovic et al 1994) using the PCR conditions described
previously by Rademaker et al (1997) Electrophoresis and pattern analysis were further
performed as described by Heyrman et al (2003) 16S rRNA gene sequencing and
phylogenetic analysis were performed as described by Heyrman and Swings (2001)
Phylogenetic trees were constructed using the BioNumerics software (Applied Maths) by
applying the neighbour-joining and maximum-parsimony methods on a multiple alignment
similarity matrix The stability of relationships was assessed by a bootstrap analysis of
1000 datasets For determination of the G+C content and levels of DNAndashDNA
hybridization approximately 1 g biomass was harvested from agar plates DNA was
purified by using a combination of the protocols of Marmur (1961) and
Pitcher et al (1989) as described by Logan et al (2000) The G+C content of the DNA
was determined by HPLC (Mesbah et al 1989) using the further specifications given by
Logan et al (2000) DNAndashDNA hybridization experiments were performed using a
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
34 Review of Literature
modification of the microplate method of Ezaki et al (1989) as described by
Willems et al (2001)
215 Preservation and conservation
Nowadays the conservation and preservation of our cultural heritage is one of the
world main concerns particularly in Europe The increasing need for non-destructive
investigation tools has become a major issue as sampling is in most cases restricted in
view of the value or the uniqueness of the object Artworks as wall paintings in buildings
and monuments of historical interest are affected by environment physical (temperature
and humidity) and biological factors (biodeteriogens) and by human (pollutant releases)
impact and therefore modified over the time The term ldquoconservationrdquo may have many
different meanings in different fields Every intervention directed to the restoration and
safeguard of works of art is commonly considered as a conservation treatment For
example conservation can involve the cleaning procedures set up by chemists or the photo
documentation of the preservation of historical memory For the appropriate conservation
of works of art even the lighting systems in a museum or the control of the visitorrsquos
movements in a site should be monitored Chemical degradation which induces the flaking
of paintings and deterioration from rain wind dust and other environmental causes is
mainly responsible for the weakening of the porous structure and the surface layers of the
materials used in works of cultural heritage (Colao et al 2005)
216 Conservation history
Wall paintings are an integral part of monuments and sites and should be preserved
in situ Many of the problems affecting wall paintings are linked to the poor condition of
the building or structure its improper use lack of maintenance frequent repairs and
alterations Also frequent restorations unnecessary uncovering and use of inappropriate
methods and materials can result in irreparable damage Substandard and inadequate
practices and professional qualifications have led to unfortunate results It is for this reason
that an appropriate document covering the principles of proper conservation-restoration of
wall paintings is necessary
The Venice Charter (1964) has provided general principles for the conservation-
restoration of cultural heritage The Amsterdam Declaration (1975) introducing the
concept of integrated conservation and the Nara Document on Authenticity (1994) dealing
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
35 Review of Literature
with cultural diversity have expanded these principles Taking into account these and
additional relevant contributions such as the ICOM-CC Code of Ethics (1984) Document
of Pavia (1997) and ECCO Professional Guidelines (1997) the aim of this document is
to provide more specific principles for the protection preservation and the conservation
restoration of wall paintings This document therefore reflects basic and universally
applicable principles and practices and does not take into account particular problems of
regions or countries which can be supplemented at regional and national level by
providing further recommendations where necessary
217 Preservation techniques of the mural paintings
The removal of fat salts varnishes and pollutants from the surfaces of the works
of art are mostly done by chemical and mechanical methods At the end of the 19th
century the practices of restoration methods that do not inhibit further future interventions
was considered acceptable During the 1960s several chemicals such as polymeric resins
were synthesized and applied as a consolidation or protection agents The accepted idea
was that these substances could be removed at any time leaving a completely unaltered
substrate On the basis of origin archaeological objects can be classified as follows
(Carretti 2005)
1 Inorganic It includes siliceous and nonsiliceous materials Archaeological materials
produced from stones terracotta ceramics and glass can be included under siliceous
materials whereas objects made of metals can be included under nonsiliceous inorganic
materials Again metal objects can be classified as ferrous metals and non-ferrous metals
Objects made of iron are termed as ferrous metal objects whereas metal objects made from
other than iron is termed as non-ferrous metal objects
2 Organic It includes archival and anthropological materials Again archival materials
include paper bhojapatra tadapatra textiles wooden objects miniature paintings whereas
anthropological objects include bone and ivory leather feather and fur etc
In the past restoration of paintings and other old artwork often involved application
of acrylic resins to consolidate and protect them One of the most important tasks for
modern restorers is thus to remove these layers because it turns out that acrylic resins not
only by drastically changing the optics of the treated artwork but in many cases they
accelerate their degradation The scientists use an oil-in-water microemulsion with the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
36 Review of Literature
organic solvent para-xylene as the oil component The matrix makes the cleaning agent
viscous so that it cannot enter very far into the pores of a painting (Carretti 2005)
Nanoparticle treatment is the logical evolution of the Ferroni-Dini method
Dispersions of kinetically stable Ca (OH)2 nanoparticles in non-aqueous solvents solved
most of the drawbacks of the microsized powders Stable dispersions of calcium hydroxide
have been successfully applied (replacing polymers) as fixatives to re-adhere lifted paint
layers during many restoration workshops in Italy and in Europe as a consolidant The
FerronindashDini method (two steps the application of a saturated solution of ammonium
carbonate (NH4)2CO3 and the treatment with a barium hydroxide solution Ba(OH)2 also
called the barium method has long been the acknowledged method for the removal of
salts that threaten paintings reinforcing at the same time the porous structure However
commercially available carbonates and hydroxide powders have dimensions of several
micrometres much larger than the pores on the paint surface This means they donrsquot
penetrate the painting well and there is also a risk of damaging the artwork by a white
glaze forming on the surface (Berger 2006) Restoration should provide the reinforcement
of the porous structure and the consolidation of the surface layer of arte facts A few
simple principles can be considered to define the most appropriate restoration method
1) The treatment should be reversible so that one can revert to the original status of the
work of art at any desired time
2) All the applied chemicals must ensure the maximum durability and the chemical
inertness
3) The applied chemicals must invert the degradation processes without altering the
chemical composition of the artefacts and their physico-chemical and mechanical
properties (Baglioni 2006)
218 Commercial preservative used for preservation of mural paintings
Cleaning was done using soft brushes vacuum cleaner and Gumma paine (dough)
a natural latex sponge Areas near the window were very dirty with black soot and were
cleaned with micro fibrous cloths moistened with synperonic N (surfactant alkyl phenol
ethoxylate based on nonyl phenol) and neutralized with clean water In several places the
paint layers had separated from the substrate (exfoli-ation) In that cases loose paint flakes
were stuck back using Paraloid B72 (10 solution in ethanol) as sparingly as possible
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
37 Review of Literature
Paraloid was injected with syringe behind the exfoliated area twice pushed and held back
with Melinex (polyester film) until fixed on the third application (Bionda et al 2002)
In a period of significant growth of molds and intensive efforts to stop the mold
contamination some of the lines of certain paintings were obscured or faded Solutions of
ethanol formalin 91 and Thiabendazole (TBZ) were used but they were not very
effective Para-formaldehyde fumigation was adopted beginning in 1981 to establish an
emergency treatment sensitivity of microorganisms from studied samples was tested
against Desogen by adding 1-3 (v v) in serial dilutions The best concentration
3 (vv) was applied with a brush to prevent spreading of the spores In order to overcome
the problem of fungal attack suitable fungicides carbendizeme or kiroxy-I or 5 solute of
N formaldehyde can be used Shellac solution in spirit or 2 solution of polyvinaycletate
in toluene can be used as preservative and consolidantsTo control insect and fungal attack
fumigants like pyrethrum DDT or 5 solution of sodium penta chlorophenate in kerosene
oil 2 to 5 solution of PVA in toluene or 2 to 5 solution of paraloid B-72 in toluene or
acetone be used (Miura 2009) Microclimatic conditions constitute a critical factor in the
conservation of cave paintings The unstable microclimatic condition is one of the factors
that always affect the state of conservation of mural paintings In the environmental-
monument system knowledge of the functional environment and climatic conditions of the
surroundings are necessary for the identification of causes of decay (Singh 2011)
Furthermore the risk of formation of indoor bioaerosols in residential and public
buildings (offices schools museums etc) has attracted interest in the last years due to
socio-economic as well as sanitary reasons (Ripka 2005) Thus it is important in aspects of
health and maintenance of Cultural Heritage to analyse the complete microflora to further
develop biocides for harmful microorganisms and methods for restoration of damaged
objects of art The biocidal testing was carried out on one representative algal species of
the two classes of algae viz Chlorococcum sp (green) and Chroococcus sp (blue-green)
found to be common in all the samples Efficiency tests were carried out both in liquid as
well as solid media containing algal suspensions by adding a biocide solution of known
concentration and determining the growth of the microorganism after the incubation
period The biocides used for the past studies were
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
8 Review of Literature
222 History of mural painting
The first paintings were Cave Paintings Ancient peoples would decorate walls of
protected Caves with paint made from dirt or charcoal mixed with spit or animal fat In
Cave paintings the pigments (often carbon black or ochre) stick to the wall partially
because the pigment gets trapped in the porous wall and partially because the binding
media (the spit or fat) dries adhering the pigment to the wall Over the years countless
graves unearthed by archaeologists exposed bodies covered in red pigment or chunks of
pigment buried alongside the bodies Red associated with blood the most life sustaining
of body fluids was the appropriate color to symbolize lifes meaning and end The word
Hematite (the source of many iron oxide pigments) is derived from the Greek word hema
meaning blood (Chakarabarti 1980)
Wall paintings have been cultural expressions of human creation throughout
history from the earliest beginnings such as rock art extending up to present day murals
Throughout history humans have used the most beautiful and durable stones for
monumental buildings Beginning in the sixth century BC marbles extracted from the
Pentelikon quarry became a common building material Abundant limestone and marble
quarries enabled the ancient Greek architects to build the Acropolis and Roman architects
to build the Forum (Saiz 2002)
Figure-21 Cave painting
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
9 Review of Literature
Figure-22 Mural painting
The oldest known Maya murals are also the most recently discovered Murals
found at the Preclassic site of San Bartolo Guatemala date to 100 BC The church of San
Pietro and the ldquooratoriordquo of San Benedetto are believed by most scholars to date from the
third quarter of the 11th century During the last decade of the same century that some
changes were made to the edifice of the church and it was decorated with mural paintings
and stucco reliefs deep in the jungle of southeastern Mexico archaeologists were surprised
that the murals are about 1350 years old
St Agatharsquos Complex was one of the preferred sites since it consists of the
hypogean environment embellished by a significant number of wall paintings some dating
back to the fourth century AD The Catacombs of St Paulrsquos constitute a complex of
interconnected underground Roman cemeteries that were in use up to the 4th century AD
There are a few surviving murals and ochre inscriptions from late Roman and early
medieval periods Decorated tablets and reliefs adorn the graves (Zammit et al 2008) The
uncovering of paintings was made from the middle of the 19th century until the 1960s
23 Indian murals
History of wall paintings in India is studied through its evolution from Ajanta to
Kerala Ajanta paintings considered to have been executed between the 2nd
century BC and
5th
century AD Murals of 6th
century AD was found at Badami (Karnataka) and
Sittannavasal Jain cave temple (Tamilnadu) Murals of Narthamala Vijayalaya Chozeswara
belong to 9th
century AD and murals of Brihadeeswara temple Tanjore (Tamil Nadu)
belong to 11th
century AD Murals seen in Kerala are dated between 16th
17th and
19th
century AD (Sivaramamurthy 1994)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
10 Review of Literature
India has one of the greatest traditions of painting of the ancient world Murals and
miniature are the two different forms of arts which intrinsically related to Indian painting
tradition The earliest evidence of murals is the beautiful frescoes painted on the caves of
Ajanta and Ellora also on the Bagh caves and Sittanvasal The oldest mural paintings date
is about 3000 years BC (Sasibhooshan 2006)
The number of wall paintings in each state of India is very large and they are
suffering from all types of deterioration and damage but in comparison facilities for their
preservation are much too small This is a very serious problem The main objective of the
present study is to develop a protective bio-based gel (Rajagopalan 2008)
24 North Indian murals
North India has a rich heritage of Mural paintings even before the Mughal period
The murals at the Vishnu Temple located at Madanpur in Lalitpur district of Uttar Pradesh
of 12th century AD reveals the skillful hands of the painters In Eastern India there are
many evidences of wall and panel paintings describing Buddhist and non- Buddhist
themes In Arunachal Pradesh and Tripura sublime mural works have been found which
needs further study Ladakh is known for its wall paintings in Alchi and Hemis
monasteries made on 11th-12th century and the Spiti Vally in Himachal Pradesh is known
for its Buddhist paintings in the Gomphas of Tabo Monastery (Havell 1982)
Ajanta is known to be the fountain head and inspiration of Buddhist paintings
across the whole of Asia There are fragments of paintings of the time of Ajanta which
survive at many Buddhist cave sites including Pitalkhora near Ellora in Maharashtra The
magnificent Kailashnath temple had been hewn out of a mountain at Ellora in the 8th
centuryThe Kashmiri style was mainly responsible for the lovely wall paintings still seen
in the beautiful monasteries at Alchi Mangyu and Sumda in Ladakh in the Tabo
monastery in the Spiti valley and in the Nako monastery in Kinnaur district Himachal
Pradesh On the western edge of the trans-Himalayan plateau in Spiti is the monastery
complex of Tabo This appears to be one of the first among the 108 monasteries built by
Yeshe It is dated around 996 AD There are also paintings of the late 9th century in the
Jain caves at Ellora (Spink 2009)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
11 Review of Literature
Figure-23 Ajanta caves
Figure-24 Mural Painting of Ajanta caves
Ellora Caves Maharashtra belong to the highest achievements of mankind both
regarding the engineering skills and arts Some 2000 years ago Pitalkhora Caves
(Maharashtra) were among the largest temple complexes in India These 11 - 14 caves
were created in 250 BC - 4th century AD In 4th century AD temples were adorned with
beautiful murals especially fine paintings have been preserved on columns of Cave 3
Traces of murals are in Cave 6 as well Already the oldest group of caves here - Buddhist
caves from 630 - 700 AD - contain paintings of Buddhist panteon Remnants of paintings
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
12 Review of Literature
are seen in the most beautiful temple - Cave 16 Kailasanatha circa 760 - 860 AD Some
Jain temples - Cave 32 (Indra Sabha) Cave 33 - contain remnants of valuable murals from
800 - 1000 AD - this artwork marks the end of ancient period in the Indian art and
beginning of medieval art (Baskaran 1975)
Figure-25 Ellora caves
There are surviving mural paintings from the 17th century onwards in Rajasthan
The verdant Pahari hills saw the finest continuation of the tradition of murals in India The
18th and 19th century paintings on the walls of the Rang Mahal in Chamba are among the
best surviving examples of Pahari murals The 18th century paintings on the walls of the
Viranchinarayan Temple at Buguda are some of the finest surviving murals of that period
in India
Figure-26 Paintings on the walls of the Rang Mahal in Chamba
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
13 Review of Literature
The most important sites of rock paintings in North India are at Bimbetka Gwalior
Tikla Ayra Bhanpura Rampura Singhauli Bhojpur Adamgrh Delware and Mirzapur
In South India they are found at Mehaboob Nagar (Andhrapradesh) Edakkal Marayoor
Perimkadavila (Kerala) Mallampadi (Tamilnadu) and Bellary (Karnataka)These
paintings were considered as the early models of mural paintingsThe mural painting of
Sittannavasal Badami Lepakshi Tanjore Vijayanagar and Kerala has a lot of similarities
(Sasibhoosan 1987)
25 South Indian murals
South India also got rich tradition of mural paintings In the reign of Cholas
Vijayanagaras and Nayakas this art reached the climax The Deccan art of Bijapur
Hyderabad and Golconda schools were influenced by the Mughal traditions and later by
European idiom Maratha murals are also shaped under the Mughal traditions and
employed oil as medium The Mural art of Kerala vividly depicted on the walls of temples
and monuments show the traces of European affinity In Tamil Nadu almost all the extent
examples of frescos have been done on rock surfaces and stone walls This is a crucial
factor in determining the quality of frescos (Havell 1982) The ceiling of the Virupaksha
temple in Hampi is covered with paintings of the 15th century The paintings on the ceiling
of the mandapa of Lepakshi temple are some of the finest mural paintings of the medieval
period in India Legends associated with Siva and Parvati Krishna and Rama were painted
on the walls of palaces and temples in Kerala from the 16th to 19th century Mural
paintings were made on the walls of all the palaces within the magnificent Orccha fort The
Raj Mahal was completely adorned with mural paintings of the 17th century
Figure-27 Virupaksha temple in Hampi
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
14 Review of Literature
Figure-28 Ceilings of Virupaksha temple Hampi
The murals on the walls of the navaranga (the central pillared hall) depict stories
from Bhagavatha and are excellent examples of 19th
century Mysore paintings The
Mallikarjunaswamy temple on the hill is one of the Panchalingas of Talakad and the
temple has a beautiful mural painting on the wall of the temple The Dariya Daulat Bagh
has excellent mural painting (Sasibhoosan 1987)
Figure-29 Paintings on the walls of Jagan mohan palace Mysore
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
15 Review of Literature
Figure-210 Painting of Raja woodeyar era
Kerala mural paintings are the frescos depicting mythology and legends which are
drawn on the walls of temples and churches in South India principally in Kerala Ancient
temples churches and palaces in Kerala South India display an abounding tradition of
mural paintings mostly dating back between the 9th to 12th centuries The murals of
Thirunadhikkara Cave Temple (now ceded to Tamilnadu) and Tiruvanchikulam are
considered the oldest relics of Keralarsquos own style of murals Fine mural paintings are
depicted in temples at Trikodithanam Ettumanur Vaikom Pundarikapuram
Udayanapuram Triprangode Guruvayoor Kumaranalloor Aymanam the Vadakkunathan
temple in Trichur and the Sri Padmanabhaswamy temple at Thiruvananthapuram Other
mural sites are in the churches at Edappally Vechur Cheppad and Mulanthuruthy and at
palaces such as the Krishnapuram Palace near Kayamkulam and the Padmanabhapuram
Palace
Figure-211 Kerala murals
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
16 Review of Literature
Figure-212 Murals paintings of Kerala temples
There are wall paintings in Badami in the Bijapur district Karnataka Some
excellent paintings exist in the Jain caves at Sitanavassal in Puddukkottai District of Tamil
Nadu Tamil Nadu gave exuberant and glorious expression to themes relating to Siva in the
temples of Panamalai and Kailashanatar in Kancheepuram In the 9th century Jain cave of
Sittannavasal in Tamil Nadu there is a marvellous lotus pond painted on the ceiling In
the heart of the Brihadeeswara temple in Thanjavur Tamil Nadu protected by massive
walls of stone are the finest paintings of the theme of Siva ever painted towards the end of
the 10th century (Sivaramamurthi 1992)
Figure-213 Kancheepuram Mural paintings
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
17 Review of Literature
Figure-214 Sculpture of Mahabalipuram
26 Methods of mural painting
In the history of mural several methods have been used The Buon fresco technique
consists of painting in pigment mixed with water on a thin layer of wet fresh lime mortar
or plaster The pigment is then absorbed by the wet plaster after a number of hours the
plaster dries and reacts with the air it is this chemical reaction which fixes the pigment
particles in the plaster After this the painting stays for a long time up to centuries in fresh
and brilliant colors A Secco painting is done on dry plaster The pigments thus require a
binding medium such as egg (tempera) glue or oil to attach the pigment to the wall
Mezzo-fresco is painted on nearly-dry plaster which is defined by the sixteenth-century
author Ignazio Pozzo as ldquofirm enough not to take a thumb-printrdquo so that the pigment only
penetrates slightly into the plaster Ancestral Hopi village archaeologists found that
fourteen kivas had painted murals and multiple layers of murals on the walls some with up
to twenty-seven layers of murals (Saturno 2006)
The colors used in painting are generally obtained from plants and minerals
Among them only such colors which are lime resistant are suitable for mural painting The
selection of proper colors for a mural painting is an important part of the work as the
longevity the painting depends on it Only mineral colors are preserved for a long time
which could be the reason for use of those colors in early days As per ldquoShilpa ratnardquo and
ldquoAgnipuranardquo the colors used in mural painting are white black red yellow blue and
green Yellow and red are from yellow ochre and red ochre Blue is generally indigo or
china blue White is the prepared wall and black is the carbon soot Mural paintings have
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
18 Review of Literature
survived centuries only on account of the identification and use of those colors which does
not have any reaction with lime (Miraseth 2006)
Originally three types of brushes were made and used flat medium and fine Flat
brushes were made from hairs behind calfrsquos ear the medium from the bottom of goats
belly and the fine brush from delicate blades of grass However in due course of time and
change use of easily available brushes from commercial market and shading of the
original colours can be distinctively noticed The use of blue colour is also noticed over the
passage of time The paintings have been brought down from the walls to plywood cloth
paper and other frames for easy to make and use purposes (Chakarabarti 1980)
27 Themes of mural painting
The subjects and themes in the murals are centered on the Hindu pantheon of Gods
and Goddesses drawn from description in the invocatory verses or Dhyana Slokas More
common representations are of Vishnu in different incarnations Ganesha and
manifestations of Siva We see murals in the Pallimanna Siva Temple devoted to Siva-
Parvatirsquos marriage the Ramayana Story being narrated on the walls of the Mattancheri
palace in the Sankara Narayana the Mahabharata is retold Murals are various scenes from
the Hindu epics and also the frolics of Lord Krishna
It would be interesting to bring into account the influence of the mural paintings on
Christianity On various churches like the St Georgersquos Orthodox Church has Christian
murals bringing out biblical characters and narrating stories from the scriptures Mar
Sabore and Afroth Church at Akapparambu in the outskirts of Ernakulam also have murals
of scenes from the bible Interestingly StMaryrsquos Church at Kanjoor has on both sides of its
entrance a battle scene between the armies of Tipu Sultan and of the English East India
Company It is also apparent that the history of Kerala Murals has its origin in the temple
walls and thus a study of Kerala Murals is not complete without pondering on the
architecture of Kerala its association with the murals (Warrier 2011)
28 Technique used in mural paintings
Indian murals executed on walls of caves structural temples walls of palaces were
based on highly developed techniques Mural painting is a composite structure of these
three basic layers the support the ground and the pigment layer In case of wall painting
the wall itself is the support This is followed by the layer or layers of plaster which
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
19 Review of Literature
constitute the ground The pigment layer is the one which contains the picture The support
is the wall which may be rock surface in a cave or a structural one These stone surfaces
which serve as carriers are rough or uneven This unevenness is itself an advantage as it
provides ldquotoothrdquo to hold the plaster on the surface The uneven surface of the wall has to be
made uniform with layers of plaster in successive gradation of fineness There is generally
one layer of rough plaster followed by one or more layers of fine plaster Ground or plaster
is a term used to mean the surface material of a wall or building which is applied as a
plastic mass made by mixing certain materials with water letting the mass set by drying
carbonation or hydration The active or setting components of plaster are commonly clay
which sets by drying lime which sets by carbonation gypsum and pozzolana which sets by
hydration (Mini 2010)
There are different mixtures for rough plaster In all the mixtures clay limestone
lime and shells in powdered form serve as the matrix The particles of which are held
together by the organic materials like gum glue extracts from barks etc are in fact
adhesives The fine plaster layer requires more careful preparation because it is the layer on
which the pigments are laid to make the picture ldquoShilparatnardquo suggest a mixture of conch
Oyster shells or white clay with gum of neem or slaked lime and coconut water Here the
consolidation is effected by the carbonation of slaked lime ie it absorbs carbon dioxide
from air and becomes carbonate Mural paintings were lime-washed from the 17th until the
beginning of 19th century A few paintings in vaults were never lime-washed for example
at Taby and Floda painted by the medieval painter Albertus Pictor (Mini 2010)
All the paintings have certain basic common characteristics There has to be a wall
or rock surface called support over which the artist goes to work A plaster base called
ground of varied thickness is laid on the support The ground may consist of one or more
layers The strength and life of the whole mural depended up on this ground over which the
painting was done It is the process of applying the final painting on the ground determines
the character of the mural whether it is fresco or tempera The mural painting is done
usually by creating wall surface free of any previous oil or paint by using solvent or by
sand blasting The brick wall is first plastered with mixture of lime and sand in the ratio of
12 A mixture of egg yolk vinegar oil colour is used in dry plaster
There are at least six stages before a Kerala Mural Painting is complete Lekhya
Karma is the first stage where sketching by pencil or crayon is done The second stage is
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
20 Review of Literature
the Rekha Karma which enhances the outlines of the sketching done The third stage called
Varna Karma breathes life into the painting with its colours Here all colours are
appropriately filled in The colouring of the human figures is done according to the
characters and their common virtues The divine and noble characters (Saatvik) are painted
in green those inclined towards power and wealth (Raajasik) is painted in shades of red
lowly mean characters (Tamasik) in white and demons in black In the fourth stage or the
Vartana Karma shading is done Fifth stage called the Lekha Karma brings us to the final
outline of the painting which is usually in black The final and the finishing touches stage
are called Devika Karma (Warrier 2011)
29 Dyes used in mural painting
Indians have been considered as fore runners in the art of natural dyeing Natural
dyes find use in the colouring of textiles drugs cosmetics etc Owing to their non-toxic
effects they are also used for colouring various food products In India there are more
than 450 plants that can yield dyes In addition to their dye-yielding characteristics some
of these plants also possess medicinal value Though there is a large plant resource base
little has been exploited so far Due to lack of availability of precise technical knowledge
on the extracting and dyeing technique it has not commercially succeeded like the
synthetic dyes (Siva 2007)
The color materials on the mural paintings in ancient India were derived from the
natural materials like terracotta chalk red ochre and yellow ochre mixed with animal fat
The dyes for painting is prepared such as white from lime Black from carbon soot of
lamps Red and yellow from minerals Blue from indigo ferra Deep red from lac A fine
coating of resin is done after the painting in order to make a shining appearance Egg yolk
and vinegar was mixed with oil colors and painted on dry plaster (Krishnakumar 1999)
Although plants exhibit a wide range of colours not all of these pigments can be
used as dyes Some do not dissolve in water some cannot be adsorbed onto fibres whereas
others fade when washed or exposed to air or sunlight It remains a mystery why plants
reward us with vibrant dyes India has a rich biodiversity and it is not only one of the
worldrsquos twelve mega diversity countries but also one of the eight major centres of origin
and diversification of domesticated taxa It has approximately 490000 plant species of
which about 17500 are angiosperms more than 400 are domesticated crop species and
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
21 Review of Literature
almost an equal number their wild relatives Thus India harbours a wealth of useful
germplasm resources and there is no doubt that the plant kingdom is a treasure-house of
diverse natural products One such product from nature is the dye (Siva 2007)
Many natural dyestuff and stains were obtained mainly from plants and dominated
as sources of natural dyes producing different colours like red yellow blue black brown
and a combination of these Almost all parts of the plants like root bark leaf fruit wood
seed flower etc produce dyes It is interesting to note that over 2000 pigments are
synthesized by various parts of plants of which only about 150 have been commercially
exploited Nearly 450 taxa are known to yield dyes in India alone of which 50 are
considered to be the most important ten of these are from roots four from barks five from
leaves seven from flowers seven from fruits three from seeds eight from wood and three
from gums and resins Some important dye-yielding plant habitats their distribution and
colouring pigment (Siva 2007)
The dye is generally prepared by boiling the crushed powder with water but
sometimes it is left to steep in cold water The solution then obtained is used generally to
dye coarse cotton fabrics Alum is generally used as a mordant Flowers of Butea
monosperma (Lam) Taubert yield an orange-coloured dye which is not fast and is easily
washed away For the purpose of colouring the material is steeped in a hot or cold
decoction of the flowers A more permanent colour is produced either by first preparing the
cloth with alum and wood ash or by adding these substances to the dye-bath The dye
indigo is produced by steeping the plant in water and allowing it to ferment This is
followed by oxidation of the solution with air in a separate vessel Mallotus philippinensis
muell yields an orange colour used for dyeing silk and wool To prepare the annatto dye
from B orellena the fruits are collected when nearly ripe The seeds and pulp are removed
from the mature fruit and macerated with water Thereafter they are either ground up into
an lsquoannatto pastersquo or dried and marketed as annatto seeds Sometimes when the seeds and
pulp are macerated with water the product is stained through a sieve and the colouring
matter which settles out is collected and partially evaporated by heat and finally dried in
the sun (Sowbhagya 2002)
The predominant colors used in rock art and cave art are black (from charcoal soot
or manganese oxide) yellow ochre (limonite) red ochre (hematite or baked limonite) and
white (kaolin clay burnt shells powdered gypsum or powdered calcium carbonate) All of
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
22 Review of Literature
theses pigments may be used on leather or raw hide as well Early cave art in Seminole
Canyon was monochromatic in red and as culture grew more sophisticated the color
palette expanded Blue Orange Brown Green and Purple are the most common colours
used in Ajantha murals White Pink Gold are occasionally represented mineral earths
containing ferric oxide and copper carbonates were used as source of red yellow and green
colours There is also evidence to establish that root of Rubia cardifolia and leaves of
Indigofera tinctoria were used as source for red and blue colours (Nayer et al 1999)
Many colors of pigments were obtained from both organic and inorganic sources in
ancient times and used to paint various surfaces such as braintan leather clothing and
accoutrements rawhide the human body etc Blue color was obtained from powdered
azurite and lapis duck manure and certain clays Fine Blue-green clay was obtained from
deposits near Mankato Michigan Organic sources of blue include Turkeys Tail a
greenish blue polypore that grows on dead decaying wood (not tannish ones) Native
Americans get Indigo from either Guatemala or Ecuador which was traded well up onto
Kansas long before the Spanish ever set foot here American Indigo has purple tones to it
but IndianJapanese indigo has green tones Berries and crushed flowers were also used to
obtain blue color by rubbing the plant material directly on the leather
An organic source of red was Cochineal It was native west of the Mississippi and
is produced from the bodies of small insects that grow on the prickly pear cactus Ladys
Bedstraw gives a good vermillion red color Harvest the roots dry them out clean the mud
etc off of them and then grind the roots really fine then soak them to extract the red
coloring The key here is drying the root first Blood was also used as red pigment Pucoon
roots also yield a red pigment (Smith 2002) Red ochre the reverse original red colours are
due to variations in iron oxide (or) calcite content and to redox conditions in the firing
produced Brown coloured ceramics owe their colour to maghemite and must be
considered as a fabrication defect due to the position of the ceramic piece in a zone where a
reducing atmosphere prevailed in the course of firingRed pigments were produced from
iron oxides like hematite or limonite and from ochre Hematite was the most frequently
used mineral It occurs in the form of aggregates of small red crystals or in the form of
bigger black crystals which are difficult to crush white was obtained mostly from
kaolinite or illite (Clottes et al 1990)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
23 Review of Literature
210 Biodetoriation of mural paintings
Historic items often contain natural biodegradable materials and have histories of
exposure to moist conditions These two conditions make them amenable to microbial
attack Microbial colonization may damage the building or the cultural asset
(Salonen 2001) Biodeteriogens are organisms involved in deterioration of artifacts They
are very specific for each type of artifact in accordance with its chemical structure and
environment They also have different nutritional requirements and act directly or
indirectly on the substrate The adhesion of microorganisms to a substrate is the result of
cell hydrophobicity and of excreted polymeric substances contained by sheaths capsules
and slimes (Colao 2005)
The surviving wall paintings and decorations in subterranean environments around
Malta are rather scarce (Buhagiar 1986 1993 1998) These include those at St Paulrsquos
Catacombs (Zammit 2008) St Agatharsquos Crypt and Catacombs (Camilleri 2001)
San Catald Catacombs Tac-Cghaqi Abbatija tad-Dejr (Buhagiar 1993) all in Rabat the
cave-sanctuary in Mellieħa (Buhagiar 1987) and the Ħal Saflieni Hypogeum in Paola
(Pace 2000) Previous studies conducted on wall paintings and decorations in Maltese
Palaeo-Christian Catacombs have involved their manufacturing techniques (Muscat 2005)
However to date limited systematic studies have been conducted into the biodeterioration
in Maltese Palaeo- Christian Catacombs The only such studies ever conducted in Malta
concerned the biodeterioration of works of art in catacombs have been carried out at St
Agatharsquos Crypt and Catacombs in Rabat (Zammit et al 2008 Psaila 2006)
Microorganisms can be responsible for the destruction of monuments buildings
and cultural heritage assets including the decay of concrete cement stones mural
paintings etc These microorganisms are not only related with biodeterioration but water-
damaged indoor building materials are frequently colonized by complex bacterial
communities and may emit mixed bioaerosols into the indoor air (Jimenez 2000) It is
well known that mural paintings are colonized by micro-organisms and can be severely
damaged by such growths (Ciferri 1999) A large number of fungal (gt50) and bacterial
taxa (70) have been detected in indoor environments Over 50 bacterial species and 14
genera novel to science were reported in the past 10 years from indoor air and historic
items indicating bacterigravea in these enviroments are as yet only fragmentarily known
(Salonen 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
24 Review of Literature
Traditionally the study of microflora which causes this biodeterioration was based
on classical cultivation methods that were mainly useful to study the physiological
potential of microorganisms but do not provide information on all microbial communities
to be found in excavated artifacts Indeed many studies using culture-independent
techniques which cultivate microorganisms from different environments may often
represent only minor components of the microbial community as a whole It is generally
accepted that cultivation methods recover less than 1 of the total microorganisms present
in environmental samples (Ward et al 1990 Amann et al 1995) Hence microbial
investigations based only on cultivation strategies cannot be regarded as reliable in terms
of reflecting the microbial diversity present in objects of art (Osburn et al 2011)
Early workers suggested that the presence of living microorganisms on stone
increased its susceptibility to damage through their water-binding capacity It has recently
been reported that the mineralogy porosity surface roughness and capacity to collect
water and organic materials control its bioreceptivity and tendency to biodeterioration
(Diakumaku 1995) In addition environmental factors as temperature light pH and
relative humidity affect the number and type of colonising species (Tiano et al 1995) and
hence the progress of colonisation Biofilms on decayed stones consist on mixed microbial
populations embedded in a polymeric matrix Fungi algae filamentous and unicellular
bacteria are found in these complex communities A variety of bacteria have been isolated
from different stone samples confirming the dominance of Gram-positive organisms
especially spore-forming bacteria such as Bacillus and filamentous actinomycetes
(Ripka 2005)
In cultivation studies of deteriorated mural and rock paintings bacterial isolates
have frequently been attributed to the genus Bacillus (Weirich 1989 Tate and Rebrikova
1991 Gonzalez et al 1999 Heyrman et al 1999 Jimenez et al 2000) Other studies that
have included DNA-based techniques to characterize the bacterial community involved in
biodeterioration have shown that a substantial part of the bacterial population is made up of
so far unknown species (Altenburger et al 1996 Rolleke et al 1996 Gurtner et al 2000
Heyrman and Swings 2001) (Heymann et al 2003)
Many potential mycotoxin producers have been detected in air and items from
indoor environments with histories of exposure to moisture for example species of
Acremonium Alternaria Aspergillus Chateomium Fusarium Eurotium Paecilomyces
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
25 Review of Literature
Penicillium Scopulariopsis Stachybotrys Trichoderma Verticillium and Wallemia
(Peltola et al 2001 Pieckova et al 2001) Not all strains of one species produce
mycotoxins and different strains may produce different toxins Whereas toxin producing
strains are frequent in crops and outdoor vegetation toxin producing isolates from indoor
environments and non living assets have only been reported of the species Aspergillus
versicolor (Nielsen et al 1998) Stachybotrys chartarum Nikulin (1997) and
Trichoderma harzianum (Peltola et al 2001) Streptomyces griseus strains producing
valinomycin occur in environments where humans can get exposed
(Andersson et al 2002) The biological properties and toxicity mechanisms of cereulide
were identical to those by valinomycin (Mikkola et al 1999 Salonen et al 2001)
The genus Paenibacillus was first proposed by Ash et al (1993) and its description
was emended by Shida et al (1997) The genus Paenibacillus is under intensive taxonomic
investigation with ten species having been formally described in the last year Heyrman amp
Swings (2001) isolated a strain originally classified as Paenibacillus sp LMG 19508
from biodeteriorated mural paintings in the Servilia tomb at the Roman necropolis of
Carmona in Seville Spain (Smerda et al 2006) Building stone and wall paintings contain
a variety of hydroscopic salts including carbonates chlorides nitrates sulfates etc
dispersed within the porous material or locally concentrated These salts are solubilised
and migrate with the water in and out of the stone Due to changes in physical parameters
the so called salt efflorescences appear on the surfaces providing extremely saline
environments and building niches for settlement of halophilic microorganisms Halite and
other hygroscopic salts can retain considerable quantities of moisture when entrapped in
the building materials and thus favouring the bacterial growth (Ripka 2005)
It is demonstrated that water-damaged indoor building materials contained
substances of microbial origin extremely toxic to eukaryotic cells and large quantities of
several microbial species known to be potentially toxic or immunopotentiating These
include peptidoglycans Gram-negative endotoxin β-13-D glucans lipoglycans and
teichoic acids and mycotoxins (Jimenez 2000) In turn these microorganisms can mediate
the crystallization process These crystallizations can produce destructive effects Some
salts may crystallize or recrystallize to different hydrates which occupy a larger space and
exert additional pressure producing cracking powdering and flaking
(Jimenez and Laiz 2000)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
26 Review of Literature
211 Types of deterioration on mural paintings
The frescos represent a variety of ecological niches where primary colonization is
due to photoautotrophic and chemolithoautotrophic microorganisms followed by
secondary colonization due to heterotrophic bacteria that obtain nutrients from various
sources (metabolites of autotrophic bacteria airborne organic contamination animal faeces
and organic compounds in the paint layers themselves) Microbial-induced deterioration
processes cause structural as well as aesthetic damage to wall paintings such as the
discoloration of materials the formation of crusts on surfaces and the loss of material
(Sarro et al 2006 Osburn et al 2011) Halophilic bacteria and archaea were thought to
be found only in extreme environments like salt lakes or black smokers However it has
been shown that mural paintings and stones are a common habitat for extremely salt
tolerant and moderate halophilic (Ripka 2005) Microbial induced deterioration processes
can cause different kinds of alterations such as discolouration of materials the formation of
crusts on surfaces and the loss of material which leads to structural damage (Ripka 2005)
First of all microorganisms can cause severe problems due to the excretion of aggressive
metabolic products such as organic or inorganic acids Secondly material components can
be used as substrates for microbial metabolism Exoenzymes such as cellulases proteases
tannases beta-glucosidase produced by fungi and bacteria are responsible for hydrolysis of
cellulose and proteins Further examples are mechanical processes caused by swelling and
shrinking of slime or mycelia penetrating inside plaster of the painting resulting in loss of
cohesion and detachment of the paint layer (Rolleke 1996 Gurtner et al 2000)
Table-21 Microbial damage on mural paintings (Rolleke 1996)
S No Damage Microbial activity
1 Green brown red grey
surface layers (patinas)
Pigments produced by microorganisms (intra-or
extracellular) as chlorophyll and carotinoids
2 Dislodging of painting layers Use of organic binders as nutrient and energy
source
3 Acid attack of carbonates Acid produced by fungi or bacteria
4 Discolouration of pigments Redox-reactions induced by fungi and
bacteria
5 Loss of paint layer Growth of microorganisms deep into the plaster
6 Hydrolysis of synthetic
polymers Chemoorganotrophic activity of bacteria and fungi
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
27 Review of Literature
Discolorations are caused by excretion of pigments and microbiologically induced
reductionoxidation-processes (Krumbein et al 1990) Degradation of the bindings is
followed by reduction of stability Oxidation of ammonium and reduced sulphur
compounds results in acidification of the environment such as Sulphuric acid and the
variety of organic acids produced by the heterotrophs cause solubilization of calcareous
binding material and chelation of metal ions (Bock et al 1993) It is now well recognised
that wall paintings can be deteriorated by microorganisms (Ciferri 1999)The growth of
microorganisms essentially results in two types of damage aesthetic and structural
Aesthetic damage implies pigment discoloration stains and formation of a biofilm on the
painted surface Structural damage is observed as cracking and disintegration of the paint
layer formation of paint blisters and degradation of support polymers or of glues and
binders resulting in detachment of paint layer from the support The colonization of mural
paintings by bacteria and other microorganisms can have different causes Provided that
favorable environmental conditions occur nutrients for heterotrophic bacteria and fungi
can be available from metabolites of autotrophic bacteria from airborne contamination and
dripping water from animal faeces but also from organic compounds in the paint layer
itself
212 Methods of studying biodeterioration
It is now well recognized that wall paintings may be deteriorated by
microorganisms as established by several studies that linked the observed damage with the
microbial community present as reviewed by Ciferri (1999) Despite this knowledge a
reliable characterization of bacteria associated with such damage is often lacking To
obtain greater insight into the bacterial community involved in biodeterioration of mural
paintings three sites (from the necropolis at Carmona Spain and the Saint-Catherine
chapel of the castle at Herberstein Austria) were sampled In previous studies from these
sites 385 isolates were analysed by fatty acid methyl ester GC and representatives of
different fatty acid clusters were further studied by 16S rRNA gene sequencing
(Heyrman and Swings 2001) Several of these representative strains showed the highest
sequence similarity with members of the genus Arthrobacter (Heyrman et al 2005)
Jimenez and Samson (1981) analysed the microbial flora of a large fresco painted
in the late 1920s in the monastery ldquoSanta Maria de la Rabidardquo (Huelva Spain) exhibiting
two types of deterioration white efflorescence and green-to-black stains
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
28 Review of Literature
Tate and Rebrikova (1990) thought autotrophic nitrifying bacteria to be the first colonisers
of damaged frescoes and building materials in the cathedral of the nativity of the Virgin in
the Pafnutii-Borovskii monastery (Russia) The bulk of research on biodeterioration of
mural paintings has focused on explaining the observed phenomena by analysing the
microflora present Following this approach a precise characterisation of the
microorganisms using a polyphasic approach was never the first goal
Only a few studies included genomic fingerprinting (16S rDNA sequence analysis)
for the characterisation of bacteria associated with damage on mural paintings
[Rolleke (1996) Pinar et al (2001)] Previous studies based on culture-dependent
techniques showed that the flora present on frescos are fungi (predominant species of
Penicillium Aspergillus Cladosporium and Engyodontium) (Guglielminetti et al 1994)
bacteria (predominant species of Bacillus Arthrobacter Micrococcus Streptomyces and
Pseudomonas) (Heyrman et al 1999) cyanobacteria and eukaryotic algae (species of
Nostoc Lyngbya and Chlorophyceae) (Arino et al 1996 Calvo et al 1993) The killing
effect of an antimicrobial agent on a microorganism can be assessed in several ways
(1) Lethal activity may be expressed as the rate of killing by a fixed concentration
of drug under controlled conditions This rate is determined by measuring the number of
viable bacteria at various time intervals The resulting graphic depiction is known as the
time-kill curve Bacterial killing rates are in part dependent on the class of antibiotic and
the concentration of this agent With certain classes of antibiotics (eg aminoglycosides
and fluoroquino-lones) the rate of killing increases with increased drug concentrations up
to a point of maximum effect This is termed concentration-dependent bactericidal activity
In contrast the killing rates of szlig-lactam agents and vancomycin are relatively slow and
continue only as long as the concentrations are in excess of the MIC This rate of killing is
termed time-dependent bactericidal activity
(2) The minimal concentration of drug needed to kill most of the viable organisms
after incubation for a fixed length of time (generally 24 hours) under a given set of
conditions is the most common estimation of bactericidal activity and is known as either
the minimal bactericidal concentration (MBC) or the minimal lethal concentration (MLC)
It will be referred to in this document as the MBC Unfortunately the definition of the
MBC (999 killing of the final inoculum) is somewhat arbitrary and separates the
bacteria into two populations ndash a segrega-tion which might not have biological relevance
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
29 Review of Literature
The determination of the MBC moreover is so subject to methodologic variables that the
clinical relevance of MBCs is nearly impossible to assess particularly for certain pathogen
and drug combinations (eg Staphylococci and beta-lactam agents)
(3) The serum of a patient receiving an antibiotic may be tested against the
infecting microorganism This can be done using time-kill curve methodology (ie serum
bactericidal rate) or using dilution methodology (ie serum bactericidal titer) The
principles of these methods as well as the influence of biological and technical factors are
similar (Barry et al 1999)
213 Microbial flora associated with deteriorated mural paintings
A great deal of research has been done in this field mainly by using cultivation dependent
methods However by using culture-dependent methods only a very small proportion of
microorganisms can be obtained Far less than 1 of organisms in the environment can be
cultivated by standard cultivation techniques (Pace 1996) Recent studies have shown that
culture-dependent techniques yielded mainly sporeforming bacteria suggesting that plating
leads to an over estimation of the number of spore-forming bacteria A wide number of
investigations have shown that in addition to chemical and physical processes
microorganisms play a major role in degradation of objects of art such as paintings stone-
works wood paper masonry leather parchment glass and metal (Ripka 2005)
A) Bacteria
In general growth of diverse organisms on mural paintings is supported by
humidity slight alkaline pH values and the presence of organic and inorganic nutrient
sources (Weirich 1989) In mural paintings pigments are suspended in water or oil often
binders such as casein and milk are used and they are supplied on the damp lime plaster
(Ciferri 1999) The calcium carbonate formed on contact with air consolidates the
pigments Thus frescos contain mainly inorganic components While chemoautotrophic
nitrifiers and thiobacilli obtain their energy for growth by oxidizing ammonium and
reducing sulphur-compounds respectively heterotrophic bacteria and fungi depend on
organically bound carbon [Tate et al (1991) Lazar (1971) Petushkova et al (1986)
Jimenez et al (1981)] Thus primary colonization of photoautotrophic Cyanobacteria
chemolithoautotrophic nitrifying bacteria and sulphuric acid producing thiobacilli represent
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
30 Review of Literature
the first supply of organic matter The death and lysis of such bacteria promotes the
secondary settlement of heterotrophic bacteria and fungal populations (Calvo et al 1991)
Bacteria may derive from plants or pollen as many sequences obtained in this study
gave high score similarities with bacteria isolated from plants like Moraxella osloensis
Enterobacter cloace Enterobacter agglomerans and Pantoea endophytica Bacteria may
also derive from animal faeces like flies Bacillus Pseudomonas Aeromonas and Panteoa
(Ripka 2005) As Lazar and Dumitru (1973) reported studying mural paintings in a
Romanian monastery the genera Bacillus Arthrobacter and Pseudomonas have been
proved to produce salt efflorescences and were even considered to cause the blanching
phenomenon of frescoes (Jimenez et al 2000) Predominant bacterial genera are Bacillus
Streptomyces Arthrobacter Micrococcus and Pseudomonas [Weirich (1989)
Tate et al (1990) Arroyo et al (1997) Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
B) Fungi
It may be concluded that there is wide variety of fungal forms present on mural
paintings but Aspergillus and Alternaria were found dominating from all the experimental
sites next to them were Cladosporium Drechestera Fusarium Curvularia Chaetomium
Memnoniella Mycelia sterelai Pencillium Emericella Stachybotrytis Trichoderma
Phoma Monodictys Humicola and Epicoccum (Garg et al 1995)
The fungal genera most commonly found in lists of isolated taxa given in literature
are Alternaria Aspergillus Chaetomium Cladosporium Fusarium Penicillium and
Verticullum [Weirich (1989) Tate et al (1990) Guglielminetti et al (1994)
Garg et al (1995) Berner et al (1997) Ciferri (1999)] Some fungi having hard fruiting
bodies represented by sclerotia pycnidia perithecia cleistothecia and stroma could
organize themselves inside the painted layer Many fungal forms having such structures
were identified from our experimental sites viz Emericella nidulans A flavus
Chaetomium sp and Phoma sp etc These structures with little increase in humidity may
cause swelling in the paint film (Garg 1995)
Strains of species of Alternaria and Cladosporium both of them identified on the
mural paintings of the Palace of Schoumlnbrunn are the most common genera isolated from
stone and mural paintings in indoor environments with standard cultivation methods
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
31 Review of Literature
(Ventosa 2004) Saprophytic species of the genus Cladosporium are among the most
abundant fungi isolated in saltern samples Commonly isolated Cyanobacteria belong to
Nostoc and eukaryotic algae to Lyngbya and members of the Chlorophyceae such as
Chlorella Pseudococcomyxa and Pseudopleurococcus [Gorbushina et al (1987)
Calvo et al (1993) Arino et al (1996)]
They grow optimally on media with low water activity due to high salt or sugar
concentrations seem to propagate 70 vegetatively in the salterns and are thus
halotolerantosmotolerant species rather than simple flush-through occurrences
Cladiosporum herbarum was frequently isolated from hypersaline waters dead and dying
plant material air soil food fruit cereals paint and textiles (Ventosa 2004)
C) Algae
Most of the painted areas in temperature climate became covered with green algae
(Pleurococcus Protococcus and Trentopholia) while under tropical conditions blue green
algae of the genera Oscillatoria and Sytonema predominated (Garg 1995) The main
factors which contribute to the growth of algae on wall paintings are the presence of
moisture in the plaster as well as availability of visible light These conditions are quite
prevalent in the tropical climate but in temperature regions also algal growth on wall
paintings have been reported [Tonolo et al (1961) Pietrini et al (1991)]
D) Actinomycetes
Usually literature refers to specific aspects eg the occurrence of cyanobacteria
and algae in caves with natural openings to sunlight or those with artificial lighting fungi
and so forth Actinomycetes have been considered to be mainly confined to soils where
they find their natural habitat but despite intensive studies there are still many gaps in our
knowledge of the role played by actinomycetes in soil processes and biodegrations of
murals cave paintings (Groth et al 1999) In addition halophilic bacteria actinomycetes
and cyanobacteria are also capable of growing on salt-affected mural paintings
(Karbowska 2003)
Monte and Ferrari (1993) reviewed the mechanisms of biodeterioration in tombs
and underground churches The role of actinomycetes in the deterioration of frescoes in
hypogean environments was stressed by Agarossi et al (1985) Monte and Ferrari (1993)
Giacobini et al (1987) described the serious damage suffered by a whole series of famous
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
32 Review of Literature
frescoes in underground environments Actinomycetes were isolated from these mural
paintings located in crypts caves and tombs About 200 strains of actinomycetes were
isolated 60 of which were identified The most frequent species were Streptomyces albus
S cinereoruber S griseolus S vinaceus and some members of the Nocardia genus
Heterotrophic bacteria and actinomycetes were the most abundant microorganisms
on the frescoes of Etruscan tombs (Agarossi et al 1985) Bettini et al (1977) studied
some of the oldest Etruscan tombs (7th to 4th century BC) and found white-grey patinas
and spots from streptomycetes in the mural paintings They related the biodeterioration to
the microclimatic conditions (eg lower temperatures high RH) Monte and Ferrari (1993)
considered that colonization of the mural paintings was the result of selective competitive
and inhibitory dynamics among different microorganisms under different and changing
environmental conditions The pigments excreted by some actinomycetes were responsible
for the violet stains found on the walls of tombs in Tarquinia Similar stains were observed
in one of the Roman tombs the Circular Mausoleum the Necropolis of Carmona Spain
from which a Streptomyces sp producing violet pigments in culture media was isolated
214 Identification of biodeteriogens
The possibility of pigments and biodeteriogens identification in frescos and stone
monitoring is offered mostly by vibrational spectroscopy infrared thermography laser
induced fluorescence (LIF) laser induced breakdown spectroscopy (LIBS) XRF (X-Ray
Fluorescence) IR and UV emission Among them laser based methods allowing for in
situ or remote characterization of artwork surface were applied successfully for
prospecting diagnosis and maintenance (Colao et al 2005) The rep-PCR fingerprinting
of the isolates allowed determination of their genotypic diversity Studies that have
compared rep-PCR genomic fingerprint analysis with DNAndashDNA relatedness studies have
shown that the two techniques yield results that are in close agreement [Nick et al (1999)
Rademaker et al (2000)] These studies therefore suggest that rep-PCR fingerprinting can
be used as a genomic screening method to differentiate at the species level and to select
representatives for DNAndashDNA reassociation experiments (Heymann et al 2003)
The characterisation of bacteria was for example often limited to isolation from
group-specific media followed by microscopy [Sorlini et al (1987) Weirich (1989)
Tate et al (1990) and in more recent studies to morphological and physiological
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
33 Review of Literature
characteristics including miniaturised and automated systems such as API and BIOLOG
[Arroyo et al (1997) Jimmenez et al (2000) and Laiz et al (2000)] or to
chemotaxonomic characteristics [Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
Wagner et al (1994) demonstrated that conventional microbiological efforts can
fail to isolate all microorganisms present in natural samples DNA-based techniques used
to identify microorganisms have revealed only a smaller fraction of bacteria isolated from
artworks (Ward et al 1990 Rolleke et al 1996) Bacterial identification using molecular
techniques especially those including the sequencing of genes coding for ribosomal
16S rRNA is very important to study bacterial communities found on artefacts One such
method is Denaturing Gradient Gel Electrophoresis (DGGE) of PCR-amplified gene
fragments coding for rRNA (Muyzer et al 1993) that allows the separation of partial
16S rDNA amplified fragments of identical length but different sequence due to their
different melting behaviour in a gel system containing a gradient of denaturants
(Jimenez 2003)
Total genomic DNA was purified for 16S rRNA gene sequencing and rep-PCR
using a slight modification of the method of Pitcher et al (1989) as described by
Heyndrickx et al (1996) rep-PCR genomic fingerprinting was performed with the REP-
and (GTG)5 primers (Versalovic et al 1994) using the PCR conditions described
previously by Rademaker et al (1997) Electrophoresis and pattern analysis were further
performed as described by Heyrman et al (2003) 16S rRNA gene sequencing and
phylogenetic analysis were performed as described by Heyrman and Swings (2001)
Phylogenetic trees were constructed using the BioNumerics software (Applied Maths) by
applying the neighbour-joining and maximum-parsimony methods on a multiple alignment
similarity matrix The stability of relationships was assessed by a bootstrap analysis of
1000 datasets For determination of the G+C content and levels of DNAndashDNA
hybridization approximately 1 g biomass was harvested from agar plates DNA was
purified by using a combination of the protocols of Marmur (1961) and
Pitcher et al (1989) as described by Logan et al (2000) The G+C content of the DNA
was determined by HPLC (Mesbah et al 1989) using the further specifications given by
Logan et al (2000) DNAndashDNA hybridization experiments were performed using a
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
34 Review of Literature
modification of the microplate method of Ezaki et al (1989) as described by
Willems et al (2001)
215 Preservation and conservation
Nowadays the conservation and preservation of our cultural heritage is one of the
world main concerns particularly in Europe The increasing need for non-destructive
investigation tools has become a major issue as sampling is in most cases restricted in
view of the value or the uniqueness of the object Artworks as wall paintings in buildings
and monuments of historical interest are affected by environment physical (temperature
and humidity) and biological factors (biodeteriogens) and by human (pollutant releases)
impact and therefore modified over the time The term ldquoconservationrdquo may have many
different meanings in different fields Every intervention directed to the restoration and
safeguard of works of art is commonly considered as a conservation treatment For
example conservation can involve the cleaning procedures set up by chemists or the photo
documentation of the preservation of historical memory For the appropriate conservation
of works of art even the lighting systems in a museum or the control of the visitorrsquos
movements in a site should be monitored Chemical degradation which induces the flaking
of paintings and deterioration from rain wind dust and other environmental causes is
mainly responsible for the weakening of the porous structure and the surface layers of the
materials used in works of cultural heritage (Colao et al 2005)
216 Conservation history
Wall paintings are an integral part of monuments and sites and should be preserved
in situ Many of the problems affecting wall paintings are linked to the poor condition of
the building or structure its improper use lack of maintenance frequent repairs and
alterations Also frequent restorations unnecessary uncovering and use of inappropriate
methods and materials can result in irreparable damage Substandard and inadequate
practices and professional qualifications have led to unfortunate results It is for this reason
that an appropriate document covering the principles of proper conservation-restoration of
wall paintings is necessary
The Venice Charter (1964) has provided general principles for the conservation-
restoration of cultural heritage The Amsterdam Declaration (1975) introducing the
concept of integrated conservation and the Nara Document on Authenticity (1994) dealing
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
35 Review of Literature
with cultural diversity have expanded these principles Taking into account these and
additional relevant contributions such as the ICOM-CC Code of Ethics (1984) Document
of Pavia (1997) and ECCO Professional Guidelines (1997) the aim of this document is
to provide more specific principles for the protection preservation and the conservation
restoration of wall paintings This document therefore reflects basic and universally
applicable principles and practices and does not take into account particular problems of
regions or countries which can be supplemented at regional and national level by
providing further recommendations where necessary
217 Preservation techniques of the mural paintings
The removal of fat salts varnishes and pollutants from the surfaces of the works
of art are mostly done by chemical and mechanical methods At the end of the 19th
century the practices of restoration methods that do not inhibit further future interventions
was considered acceptable During the 1960s several chemicals such as polymeric resins
were synthesized and applied as a consolidation or protection agents The accepted idea
was that these substances could be removed at any time leaving a completely unaltered
substrate On the basis of origin archaeological objects can be classified as follows
(Carretti 2005)
1 Inorganic It includes siliceous and nonsiliceous materials Archaeological materials
produced from stones terracotta ceramics and glass can be included under siliceous
materials whereas objects made of metals can be included under nonsiliceous inorganic
materials Again metal objects can be classified as ferrous metals and non-ferrous metals
Objects made of iron are termed as ferrous metal objects whereas metal objects made from
other than iron is termed as non-ferrous metal objects
2 Organic It includes archival and anthropological materials Again archival materials
include paper bhojapatra tadapatra textiles wooden objects miniature paintings whereas
anthropological objects include bone and ivory leather feather and fur etc
In the past restoration of paintings and other old artwork often involved application
of acrylic resins to consolidate and protect them One of the most important tasks for
modern restorers is thus to remove these layers because it turns out that acrylic resins not
only by drastically changing the optics of the treated artwork but in many cases they
accelerate their degradation The scientists use an oil-in-water microemulsion with the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
36 Review of Literature
organic solvent para-xylene as the oil component The matrix makes the cleaning agent
viscous so that it cannot enter very far into the pores of a painting (Carretti 2005)
Nanoparticle treatment is the logical evolution of the Ferroni-Dini method
Dispersions of kinetically stable Ca (OH)2 nanoparticles in non-aqueous solvents solved
most of the drawbacks of the microsized powders Stable dispersions of calcium hydroxide
have been successfully applied (replacing polymers) as fixatives to re-adhere lifted paint
layers during many restoration workshops in Italy and in Europe as a consolidant The
FerronindashDini method (two steps the application of a saturated solution of ammonium
carbonate (NH4)2CO3 and the treatment with a barium hydroxide solution Ba(OH)2 also
called the barium method has long been the acknowledged method for the removal of
salts that threaten paintings reinforcing at the same time the porous structure However
commercially available carbonates and hydroxide powders have dimensions of several
micrometres much larger than the pores on the paint surface This means they donrsquot
penetrate the painting well and there is also a risk of damaging the artwork by a white
glaze forming on the surface (Berger 2006) Restoration should provide the reinforcement
of the porous structure and the consolidation of the surface layer of arte facts A few
simple principles can be considered to define the most appropriate restoration method
1) The treatment should be reversible so that one can revert to the original status of the
work of art at any desired time
2) All the applied chemicals must ensure the maximum durability and the chemical
inertness
3) The applied chemicals must invert the degradation processes without altering the
chemical composition of the artefacts and their physico-chemical and mechanical
properties (Baglioni 2006)
218 Commercial preservative used for preservation of mural paintings
Cleaning was done using soft brushes vacuum cleaner and Gumma paine (dough)
a natural latex sponge Areas near the window were very dirty with black soot and were
cleaned with micro fibrous cloths moistened with synperonic N (surfactant alkyl phenol
ethoxylate based on nonyl phenol) and neutralized with clean water In several places the
paint layers had separated from the substrate (exfoli-ation) In that cases loose paint flakes
were stuck back using Paraloid B72 (10 solution in ethanol) as sparingly as possible
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
37 Review of Literature
Paraloid was injected with syringe behind the exfoliated area twice pushed and held back
with Melinex (polyester film) until fixed on the third application (Bionda et al 2002)
In a period of significant growth of molds and intensive efforts to stop the mold
contamination some of the lines of certain paintings were obscured or faded Solutions of
ethanol formalin 91 and Thiabendazole (TBZ) were used but they were not very
effective Para-formaldehyde fumigation was adopted beginning in 1981 to establish an
emergency treatment sensitivity of microorganisms from studied samples was tested
against Desogen by adding 1-3 (v v) in serial dilutions The best concentration
3 (vv) was applied with a brush to prevent spreading of the spores In order to overcome
the problem of fungal attack suitable fungicides carbendizeme or kiroxy-I or 5 solute of
N formaldehyde can be used Shellac solution in spirit or 2 solution of polyvinaycletate
in toluene can be used as preservative and consolidantsTo control insect and fungal attack
fumigants like pyrethrum DDT or 5 solution of sodium penta chlorophenate in kerosene
oil 2 to 5 solution of PVA in toluene or 2 to 5 solution of paraloid B-72 in toluene or
acetone be used (Miura 2009) Microclimatic conditions constitute a critical factor in the
conservation of cave paintings The unstable microclimatic condition is one of the factors
that always affect the state of conservation of mural paintings In the environmental-
monument system knowledge of the functional environment and climatic conditions of the
surroundings are necessary for the identification of causes of decay (Singh 2011)
Furthermore the risk of formation of indoor bioaerosols in residential and public
buildings (offices schools museums etc) has attracted interest in the last years due to
socio-economic as well as sanitary reasons (Ripka 2005) Thus it is important in aspects of
health and maintenance of Cultural Heritage to analyse the complete microflora to further
develop biocides for harmful microorganisms and methods for restoration of damaged
objects of art The biocidal testing was carried out on one representative algal species of
the two classes of algae viz Chlorococcum sp (green) and Chroococcus sp (blue-green)
found to be common in all the samples Efficiency tests were carried out both in liquid as
well as solid media containing algal suspensions by adding a biocide solution of known
concentration and determining the growth of the microorganism after the incubation
period The biocides used for the past studies were
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
9 Review of Literature
Figure-22 Mural painting
The oldest known Maya murals are also the most recently discovered Murals
found at the Preclassic site of San Bartolo Guatemala date to 100 BC The church of San
Pietro and the ldquooratoriordquo of San Benedetto are believed by most scholars to date from the
third quarter of the 11th century During the last decade of the same century that some
changes were made to the edifice of the church and it was decorated with mural paintings
and stucco reliefs deep in the jungle of southeastern Mexico archaeologists were surprised
that the murals are about 1350 years old
St Agatharsquos Complex was one of the preferred sites since it consists of the
hypogean environment embellished by a significant number of wall paintings some dating
back to the fourth century AD The Catacombs of St Paulrsquos constitute a complex of
interconnected underground Roman cemeteries that were in use up to the 4th century AD
There are a few surviving murals and ochre inscriptions from late Roman and early
medieval periods Decorated tablets and reliefs adorn the graves (Zammit et al 2008) The
uncovering of paintings was made from the middle of the 19th century until the 1960s
23 Indian murals
History of wall paintings in India is studied through its evolution from Ajanta to
Kerala Ajanta paintings considered to have been executed between the 2nd
century BC and
5th
century AD Murals of 6th
century AD was found at Badami (Karnataka) and
Sittannavasal Jain cave temple (Tamilnadu) Murals of Narthamala Vijayalaya Chozeswara
belong to 9th
century AD and murals of Brihadeeswara temple Tanjore (Tamil Nadu)
belong to 11th
century AD Murals seen in Kerala are dated between 16th
17th and
19th
century AD (Sivaramamurthy 1994)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
10 Review of Literature
India has one of the greatest traditions of painting of the ancient world Murals and
miniature are the two different forms of arts which intrinsically related to Indian painting
tradition The earliest evidence of murals is the beautiful frescoes painted on the caves of
Ajanta and Ellora also on the Bagh caves and Sittanvasal The oldest mural paintings date
is about 3000 years BC (Sasibhooshan 2006)
The number of wall paintings in each state of India is very large and they are
suffering from all types of deterioration and damage but in comparison facilities for their
preservation are much too small This is a very serious problem The main objective of the
present study is to develop a protective bio-based gel (Rajagopalan 2008)
24 North Indian murals
North India has a rich heritage of Mural paintings even before the Mughal period
The murals at the Vishnu Temple located at Madanpur in Lalitpur district of Uttar Pradesh
of 12th century AD reveals the skillful hands of the painters In Eastern India there are
many evidences of wall and panel paintings describing Buddhist and non- Buddhist
themes In Arunachal Pradesh and Tripura sublime mural works have been found which
needs further study Ladakh is known for its wall paintings in Alchi and Hemis
monasteries made on 11th-12th century and the Spiti Vally in Himachal Pradesh is known
for its Buddhist paintings in the Gomphas of Tabo Monastery (Havell 1982)
Ajanta is known to be the fountain head and inspiration of Buddhist paintings
across the whole of Asia There are fragments of paintings of the time of Ajanta which
survive at many Buddhist cave sites including Pitalkhora near Ellora in Maharashtra The
magnificent Kailashnath temple had been hewn out of a mountain at Ellora in the 8th
centuryThe Kashmiri style was mainly responsible for the lovely wall paintings still seen
in the beautiful monasteries at Alchi Mangyu and Sumda in Ladakh in the Tabo
monastery in the Spiti valley and in the Nako monastery in Kinnaur district Himachal
Pradesh On the western edge of the trans-Himalayan plateau in Spiti is the monastery
complex of Tabo This appears to be one of the first among the 108 monasteries built by
Yeshe It is dated around 996 AD There are also paintings of the late 9th century in the
Jain caves at Ellora (Spink 2009)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
11 Review of Literature
Figure-23 Ajanta caves
Figure-24 Mural Painting of Ajanta caves
Ellora Caves Maharashtra belong to the highest achievements of mankind both
regarding the engineering skills and arts Some 2000 years ago Pitalkhora Caves
(Maharashtra) were among the largest temple complexes in India These 11 - 14 caves
were created in 250 BC - 4th century AD In 4th century AD temples were adorned with
beautiful murals especially fine paintings have been preserved on columns of Cave 3
Traces of murals are in Cave 6 as well Already the oldest group of caves here - Buddhist
caves from 630 - 700 AD - contain paintings of Buddhist panteon Remnants of paintings
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
12 Review of Literature
are seen in the most beautiful temple - Cave 16 Kailasanatha circa 760 - 860 AD Some
Jain temples - Cave 32 (Indra Sabha) Cave 33 - contain remnants of valuable murals from
800 - 1000 AD - this artwork marks the end of ancient period in the Indian art and
beginning of medieval art (Baskaran 1975)
Figure-25 Ellora caves
There are surviving mural paintings from the 17th century onwards in Rajasthan
The verdant Pahari hills saw the finest continuation of the tradition of murals in India The
18th and 19th century paintings on the walls of the Rang Mahal in Chamba are among the
best surviving examples of Pahari murals The 18th century paintings on the walls of the
Viranchinarayan Temple at Buguda are some of the finest surviving murals of that period
in India
Figure-26 Paintings on the walls of the Rang Mahal in Chamba
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
13 Review of Literature
The most important sites of rock paintings in North India are at Bimbetka Gwalior
Tikla Ayra Bhanpura Rampura Singhauli Bhojpur Adamgrh Delware and Mirzapur
In South India they are found at Mehaboob Nagar (Andhrapradesh) Edakkal Marayoor
Perimkadavila (Kerala) Mallampadi (Tamilnadu) and Bellary (Karnataka)These
paintings were considered as the early models of mural paintingsThe mural painting of
Sittannavasal Badami Lepakshi Tanjore Vijayanagar and Kerala has a lot of similarities
(Sasibhoosan 1987)
25 South Indian murals
South India also got rich tradition of mural paintings In the reign of Cholas
Vijayanagaras and Nayakas this art reached the climax The Deccan art of Bijapur
Hyderabad and Golconda schools were influenced by the Mughal traditions and later by
European idiom Maratha murals are also shaped under the Mughal traditions and
employed oil as medium The Mural art of Kerala vividly depicted on the walls of temples
and monuments show the traces of European affinity In Tamil Nadu almost all the extent
examples of frescos have been done on rock surfaces and stone walls This is a crucial
factor in determining the quality of frescos (Havell 1982) The ceiling of the Virupaksha
temple in Hampi is covered with paintings of the 15th century The paintings on the ceiling
of the mandapa of Lepakshi temple are some of the finest mural paintings of the medieval
period in India Legends associated with Siva and Parvati Krishna and Rama were painted
on the walls of palaces and temples in Kerala from the 16th to 19th century Mural
paintings were made on the walls of all the palaces within the magnificent Orccha fort The
Raj Mahal was completely adorned with mural paintings of the 17th century
Figure-27 Virupaksha temple in Hampi
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
14 Review of Literature
Figure-28 Ceilings of Virupaksha temple Hampi
The murals on the walls of the navaranga (the central pillared hall) depict stories
from Bhagavatha and are excellent examples of 19th
century Mysore paintings The
Mallikarjunaswamy temple on the hill is one of the Panchalingas of Talakad and the
temple has a beautiful mural painting on the wall of the temple The Dariya Daulat Bagh
has excellent mural painting (Sasibhoosan 1987)
Figure-29 Paintings on the walls of Jagan mohan palace Mysore
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
15 Review of Literature
Figure-210 Painting of Raja woodeyar era
Kerala mural paintings are the frescos depicting mythology and legends which are
drawn on the walls of temples and churches in South India principally in Kerala Ancient
temples churches and palaces in Kerala South India display an abounding tradition of
mural paintings mostly dating back between the 9th to 12th centuries The murals of
Thirunadhikkara Cave Temple (now ceded to Tamilnadu) and Tiruvanchikulam are
considered the oldest relics of Keralarsquos own style of murals Fine mural paintings are
depicted in temples at Trikodithanam Ettumanur Vaikom Pundarikapuram
Udayanapuram Triprangode Guruvayoor Kumaranalloor Aymanam the Vadakkunathan
temple in Trichur and the Sri Padmanabhaswamy temple at Thiruvananthapuram Other
mural sites are in the churches at Edappally Vechur Cheppad and Mulanthuruthy and at
palaces such as the Krishnapuram Palace near Kayamkulam and the Padmanabhapuram
Palace
Figure-211 Kerala murals
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
16 Review of Literature
Figure-212 Murals paintings of Kerala temples
There are wall paintings in Badami in the Bijapur district Karnataka Some
excellent paintings exist in the Jain caves at Sitanavassal in Puddukkottai District of Tamil
Nadu Tamil Nadu gave exuberant and glorious expression to themes relating to Siva in the
temples of Panamalai and Kailashanatar in Kancheepuram In the 9th century Jain cave of
Sittannavasal in Tamil Nadu there is a marvellous lotus pond painted on the ceiling In
the heart of the Brihadeeswara temple in Thanjavur Tamil Nadu protected by massive
walls of stone are the finest paintings of the theme of Siva ever painted towards the end of
the 10th century (Sivaramamurthi 1992)
Figure-213 Kancheepuram Mural paintings
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
17 Review of Literature
Figure-214 Sculpture of Mahabalipuram
26 Methods of mural painting
In the history of mural several methods have been used The Buon fresco technique
consists of painting in pigment mixed with water on a thin layer of wet fresh lime mortar
or plaster The pigment is then absorbed by the wet plaster after a number of hours the
plaster dries and reacts with the air it is this chemical reaction which fixes the pigment
particles in the plaster After this the painting stays for a long time up to centuries in fresh
and brilliant colors A Secco painting is done on dry plaster The pigments thus require a
binding medium such as egg (tempera) glue or oil to attach the pigment to the wall
Mezzo-fresco is painted on nearly-dry plaster which is defined by the sixteenth-century
author Ignazio Pozzo as ldquofirm enough not to take a thumb-printrdquo so that the pigment only
penetrates slightly into the plaster Ancestral Hopi village archaeologists found that
fourteen kivas had painted murals and multiple layers of murals on the walls some with up
to twenty-seven layers of murals (Saturno 2006)
The colors used in painting are generally obtained from plants and minerals
Among them only such colors which are lime resistant are suitable for mural painting The
selection of proper colors for a mural painting is an important part of the work as the
longevity the painting depends on it Only mineral colors are preserved for a long time
which could be the reason for use of those colors in early days As per ldquoShilpa ratnardquo and
ldquoAgnipuranardquo the colors used in mural painting are white black red yellow blue and
green Yellow and red are from yellow ochre and red ochre Blue is generally indigo or
china blue White is the prepared wall and black is the carbon soot Mural paintings have
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
18 Review of Literature
survived centuries only on account of the identification and use of those colors which does
not have any reaction with lime (Miraseth 2006)
Originally three types of brushes were made and used flat medium and fine Flat
brushes were made from hairs behind calfrsquos ear the medium from the bottom of goats
belly and the fine brush from delicate blades of grass However in due course of time and
change use of easily available brushes from commercial market and shading of the
original colours can be distinctively noticed The use of blue colour is also noticed over the
passage of time The paintings have been brought down from the walls to plywood cloth
paper and other frames for easy to make and use purposes (Chakarabarti 1980)
27 Themes of mural painting
The subjects and themes in the murals are centered on the Hindu pantheon of Gods
and Goddesses drawn from description in the invocatory verses or Dhyana Slokas More
common representations are of Vishnu in different incarnations Ganesha and
manifestations of Siva We see murals in the Pallimanna Siva Temple devoted to Siva-
Parvatirsquos marriage the Ramayana Story being narrated on the walls of the Mattancheri
palace in the Sankara Narayana the Mahabharata is retold Murals are various scenes from
the Hindu epics and also the frolics of Lord Krishna
It would be interesting to bring into account the influence of the mural paintings on
Christianity On various churches like the St Georgersquos Orthodox Church has Christian
murals bringing out biblical characters and narrating stories from the scriptures Mar
Sabore and Afroth Church at Akapparambu in the outskirts of Ernakulam also have murals
of scenes from the bible Interestingly StMaryrsquos Church at Kanjoor has on both sides of its
entrance a battle scene between the armies of Tipu Sultan and of the English East India
Company It is also apparent that the history of Kerala Murals has its origin in the temple
walls and thus a study of Kerala Murals is not complete without pondering on the
architecture of Kerala its association with the murals (Warrier 2011)
28 Technique used in mural paintings
Indian murals executed on walls of caves structural temples walls of palaces were
based on highly developed techniques Mural painting is a composite structure of these
three basic layers the support the ground and the pigment layer In case of wall painting
the wall itself is the support This is followed by the layer or layers of plaster which
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
19 Review of Literature
constitute the ground The pigment layer is the one which contains the picture The support
is the wall which may be rock surface in a cave or a structural one These stone surfaces
which serve as carriers are rough or uneven This unevenness is itself an advantage as it
provides ldquotoothrdquo to hold the plaster on the surface The uneven surface of the wall has to be
made uniform with layers of plaster in successive gradation of fineness There is generally
one layer of rough plaster followed by one or more layers of fine plaster Ground or plaster
is a term used to mean the surface material of a wall or building which is applied as a
plastic mass made by mixing certain materials with water letting the mass set by drying
carbonation or hydration The active or setting components of plaster are commonly clay
which sets by drying lime which sets by carbonation gypsum and pozzolana which sets by
hydration (Mini 2010)
There are different mixtures for rough plaster In all the mixtures clay limestone
lime and shells in powdered form serve as the matrix The particles of which are held
together by the organic materials like gum glue extracts from barks etc are in fact
adhesives The fine plaster layer requires more careful preparation because it is the layer on
which the pigments are laid to make the picture ldquoShilparatnardquo suggest a mixture of conch
Oyster shells or white clay with gum of neem or slaked lime and coconut water Here the
consolidation is effected by the carbonation of slaked lime ie it absorbs carbon dioxide
from air and becomes carbonate Mural paintings were lime-washed from the 17th until the
beginning of 19th century A few paintings in vaults were never lime-washed for example
at Taby and Floda painted by the medieval painter Albertus Pictor (Mini 2010)
All the paintings have certain basic common characteristics There has to be a wall
or rock surface called support over which the artist goes to work A plaster base called
ground of varied thickness is laid on the support The ground may consist of one or more
layers The strength and life of the whole mural depended up on this ground over which the
painting was done It is the process of applying the final painting on the ground determines
the character of the mural whether it is fresco or tempera The mural painting is done
usually by creating wall surface free of any previous oil or paint by using solvent or by
sand blasting The brick wall is first plastered with mixture of lime and sand in the ratio of
12 A mixture of egg yolk vinegar oil colour is used in dry plaster
There are at least six stages before a Kerala Mural Painting is complete Lekhya
Karma is the first stage where sketching by pencil or crayon is done The second stage is
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
20 Review of Literature
the Rekha Karma which enhances the outlines of the sketching done The third stage called
Varna Karma breathes life into the painting with its colours Here all colours are
appropriately filled in The colouring of the human figures is done according to the
characters and their common virtues The divine and noble characters (Saatvik) are painted
in green those inclined towards power and wealth (Raajasik) is painted in shades of red
lowly mean characters (Tamasik) in white and demons in black In the fourth stage or the
Vartana Karma shading is done Fifth stage called the Lekha Karma brings us to the final
outline of the painting which is usually in black The final and the finishing touches stage
are called Devika Karma (Warrier 2011)
29 Dyes used in mural painting
Indians have been considered as fore runners in the art of natural dyeing Natural
dyes find use in the colouring of textiles drugs cosmetics etc Owing to their non-toxic
effects they are also used for colouring various food products In India there are more
than 450 plants that can yield dyes In addition to their dye-yielding characteristics some
of these plants also possess medicinal value Though there is a large plant resource base
little has been exploited so far Due to lack of availability of precise technical knowledge
on the extracting and dyeing technique it has not commercially succeeded like the
synthetic dyes (Siva 2007)
The color materials on the mural paintings in ancient India were derived from the
natural materials like terracotta chalk red ochre and yellow ochre mixed with animal fat
The dyes for painting is prepared such as white from lime Black from carbon soot of
lamps Red and yellow from minerals Blue from indigo ferra Deep red from lac A fine
coating of resin is done after the painting in order to make a shining appearance Egg yolk
and vinegar was mixed with oil colors and painted on dry plaster (Krishnakumar 1999)
Although plants exhibit a wide range of colours not all of these pigments can be
used as dyes Some do not dissolve in water some cannot be adsorbed onto fibres whereas
others fade when washed or exposed to air or sunlight It remains a mystery why plants
reward us with vibrant dyes India has a rich biodiversity and it is not only one of the
worldrsquos twelve mega diversity countries but also one of the eight major centres of origin
and diversification of domesticated taxa It has approximately 490000 plant species of
which about 17500 are angiosperms more than 400 are domesticated crop species and
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
21 Review of Literature
almost an equal number their wild relatives Thus India harbours a wealth of useful
germplasm resources and there is no doubt that the plant kingdom is a treasure-house of
diverse natural products One such product from nature is the dye (Siva 2007)
Many natural dyestuff and stains were obtained mainly from plants and dominated
as sources of natural dyes producing different colours like red yellow blue black brown
and a combination of these Almost all parts of the plants like root bark leaf fruit wood
seed flower etc produce dyes It is interesting to note that over 2000 pigments are
synthesized by various parts of plants of which only about 150 have been commercially
exploited Nearly 450 taxa are known to yield dyes in India alone of which 50 are
considered to be the most important ten of these are from roots four from barks five from
leaves seven from flowers seven from fruits three from seeds eight from wood and three
from gums and resins Some important dye-yielding plant habitats their distribution and
colouring pigment (Siva 2007)
The dye is generally prepared by boiling the crushed powder with water but
sometimes it is left to steep in cold water The solution then obtained is used generally to
dye coarse cotton fabrics Alum is generally used as a mordant Flowers of Butea
monosperma (Lam) Taubert yield an orange-coloured dye which is not fast and is easily
washed away For the purpose of colouring the material is steeped in a hot or cold
decoction of the flowers A more permanent colour is produced either by first preparing the
cloth with alum and wood ash or by adding these substances to the dye-bath The dye
indigo is produced by steeping the plant in water and allowing it to ferment This is
followed by oxidation of the solution with air in a separate vessel Mallotus philippinensis
muell yields an orange colour used for dyeing silk and wool To prepare the annatto dye
from B orellena the fruits are collected when nearly ripe The seeds and pulp are removed
from the mature fruit and macerated with water Thereafter they are either ground up into
an lsquoannatto pastersquo or dried and marketed as annatto seeds Sometimes when the seeds and
pulp are macerated with water the product is stained through a sieve and the colouring
matter which settles out is collected and partially evaporated by heat and finally dried in
the sun (Sowbhagya 2002)
The predominant colors used in rock art and cave art are black (from charcoal soot
or manganese oxide) yellow ochre (limonite) red ochre (hematite or baked limonite) and
white (kaolin clay burnt shells powdered gypsum or powdered calcium carbonate) All of
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
22 Review of Literature
theses pigments may be used on leather or raw hide as well Early cave art in Seminole
Canyon was monochromatic in red and as culture grew more sophisticated the color
palette expanded Blue Orange Brown Green and Purple are the most common colours
used in Ajantha murals White Pink Gold are occasionally represented mineral earths
containing ferric oxide and copper carbonates were used as source of red yellow and green
colours There is also evidence to establish that root of Rubia cardifolia and leaves of
Indigofera tinctoria were used as source for red and blue colours (Nayer et al 1999)
Many colors of pigments were obtained from both organic and inorganic sources in
ancient times and used to paint various surfaces such as braintan leather clothing and
accoutrements rawhide the human body etc Blue color was obtained from powdered
azurite and lapis duck manure and certain clays Fine Blue-green clay was obtained from
deposits near Mankato Michigan Organic sources of blue include Turkeys Tail a
greenish blue polypore that grows on dead decaying wood (not tannish ones) Native
Americans get Indigo from either Guatemala or Ecuador which was traded well up onto
Kansas long before the Spanish ever set foot here American Indigo has purple tones to it
but IndianJapanese indigo has green tones Berries and crushed flowers were also used to
obtain blue color by rubbing the plant material directly on the leather
An organic source of red was Cochineal It was native west of the Mississippi and
is produced from the bodies of small insects that grow on the prickly pear cactus Ladys
Bedstraw gives a good vermillion red color Harvest the roots dry them out clean the mud
etc off of them and then grind the roots really fine then soak them to extract the red
coloring The key here is drying the root first Blood was also used as red pigment Pucoon
roots also yield a red pigment (Smith 2002) Red ochre the reverse original red colours are
due to variations in iron oxide (or) calcite content and to redox conditions in the firing
produced Brown coloured ceramics owe their colour to maghemite and must be
considered as a fabrication defect due to the position of the ceramic piece in a zone where a
reducing atmosphere prevailed in the course of firingRed pigments were produced from
iron oxides like hematite or limonite and from ochre Hematite was the most frequently
used mineral It occurs in the form of aggregates of small red crystals or in the form of
bigger black crystals which are difficult to crush white was obtained mostly from
kaolinite or illite (Clottes et al 1990)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
23 Review of Literature
210 Biodetoriation of mural paintings
Historic items often contain natural biodegradable materials and have histories of
exposure to moist conditions These two conditions make them amenable to microbial
attack Microbial colonization may damage the building or the cultural asset
(Salonen 2001) Biodeteriogens are organisms involved in deterioration of artifacts They
are very specific for each type of artifact in accordance with its chemical structure and
environment They also have different nutritional requirements and act directly or
indirectly on the substrate The adhesion of microorganisms to a substrate is the result of
cell hydrophobicity and of excreted polymeric substances contained by sheaths capsules
and slimes (Colao 2005)
The surviving wall paintings and decorations in subterranean environments around
Malta are rather scarce (Buhagiar 1986 1993 1998) These include those at St Paulrsquos
Catacombs (Zammit 2008) St Agatharsquos Crypt and Catacombs (Camilleri 2001)
San Catald Catacombs Tac-Cghaqi Abbatija tad-Dejr (Buhagiar 1993) all in Rabat the
cave-sanctuary in Mellieħa (Buhagiar 1987) and the Ħal Saflieni Hypogeum in Paola
(Pace 2000) Previous studies conducted on wall paintings and decorations in Maltese
Palaeo-Christian Catacombs have involved their manufacturing techniques (Muscat 2005)
However to date limited systematic studies have been conducted into the biodeterioration
in Maltese Palaeo- Christian Catacombs The only such studies ever conducted in Malta
concerned the biodeterioration of works of art in catacombs have been carried out at St
Agatharsquos Crypt and Catacombs in Rabat (Zammit et al 2008 Psaila 2006)
Microorganisms can be responsible for the destruction of monuments buildings
and cultural heritage assets including the decay of concrete cement stones mural
paintings etc These microorganisms are not only related with biodeterioration but water-
damaged indoor building materials are frequently colonized by complex bacterial
communities and may emit mixed bioaerosols into the indoor air (Jimenez 2000) It is
well known that mural paintings are colonized by micro-organisms and can be severely
damaged by such growths (Ciferri 1999) A large number of fungal (gt50) and bacterial
taxa (70) have been detected in indoor environments Over 50 bacterial species and 14
genera novel to science were reported in the past 10 years from indoor air and historic
items indicating bacterigravea in these enviroments are as yet only fragmentarily known
(Salonen 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
24 Review of Literature
Traditionally the study of microflora which causes this biodeterioration was based
on classical cultivation methods that were mainly useful to study the physiological
potential of microorganisms but do not provide information on all microbial communities
to be found in excavated artifacts Indeed many studies using culture-independent
techniques which cultivate microorganisms from different environments may often
represent only minor components of the microbial community as a whole It is generally
accepted that cultivation methods recover less than 1 of the total microorganisms present
in environmental samples (Ward et al 1990 Amann et al 1995) Hence microbial
investigations based only on cultivation strategies cannot be regarded as reliable in terms
of reflecting the microbial diversity present in objects of art (Osburn et al 2011)
Early workers suggested that the presence of living microorganisms on stone
increased its susceptibility to damage through their water-binding capacity It has recently
been reported that the mineralogy porosity surface roughness and capacity to collect
water and organic materials control its bioreceptivity and tendency to biodeterioration
(Diakumaku 1995) In addition environmental factors as temperature light pH and
relative humidity affect the number and type of colonising species (Tiano et al 1995) and
hence the progress of colonisation Biofilms on decayed stones consist on mixed microbial
populations embedded in a polymeric matrix Fungi algae filamentous and unicellular
bacteria are found in these complex communities A variety of bacteria have been isolated
from different stone samples confirming the dominance of Gram-positive organisms
especially spore-forming bacteria such as Bacillus and filamentous actinomycetes
(Ripka 2005)
In cultivation studies of deteriorated mural and rock paintings bacterial isolates
have frequently been attributed to the genus Bacillus (Weirich 1989 Tate and Rebrikova
1991 Gonzalez et al 1999 Heyrman et al 1999 Jimenez et al 2000) Other studies that
have included DNA-based techniques to characterize the bacterial community involved in
biodeterioration have shown that a substantial part of the bacterial population is made up of
so far unknown species (Altenburger et al 1996 Rolleke et al 1996 Gurtner et al 2000
Heyrman and Swings 2001) (Heymann et al 2003)
Many potential mycotoxin producers have been detected in air and items from
indoor environments with histories of exposure to moisture for example species of
Acremonium Alternaria Aspergillus Chateomium Fusarium Eurotium Paecilomyces
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
25 Review of Literature
Penicillium Scopulariopsis Stachybotrys Trichoderma Verticillium and Wallemia
(Peltola et al 2001 Pieckova et al 2001) Not all strains of one species produce
mycotoxins and different strains may produce different toxins Whereas toxin producing
strains are frequent in crops and outdoor vegetation toxin producing isolates from indoor
environments and non living assets have only been reported of the species Aspergillus
versicolor (Nielsen et al 1998) Stachybotrys chartarum Nikulin (1997) and
Trichoderma harzianum (Peltola et al 2001) Streptomyces griseus strains producing
valinomycin occur in environments where humans can get exposed
(Andersson et al 2002) The biological properties and toxicity mechanisms of cereulide
were identical to those by valinomycin (Mikkola et al 1999 Salonen et al 2001)
The genus Paenibacillus was first proposed by Ash et al (1993) and its description
was emended by Shida et al (1997) The genus Paenibacillus is under intensive taxonomic
investigation with ten species having been formally described in the last year Heyrman amp
Swings (2001) isolated a strain originally classified as Paenibacillus sp LMG 19508
from biodeteriorated mural paintings in the Servilia tomb at the Roman necropolis of
Carmona in Seville Spain (Smerda et al 2006) Building stone and wall paintings contain
a variety of hydroscopic salts including carbonates chlorides nitrates sulfates etc
dispersed within the porous material or locally concentrated These salts are solubilised
and migrate with the water in and out of the stone Due to changes in physical parameters
the so called salt efflorescences appear on the surfaces providing extremely saline
environments and building niches for settlement of halophilic microorganisms Halite and
other hygroscopic salts can retain considerable quantities of moisture when entrapped in
the building materials and thus favouring the bacterial growth (Ripka 2005)
It is demonstrated that water-damaged indoor building materials contained
substances of microbial origin extremely toxic to eukaryotic cells and large quantities of
several microbial species known to be potentially toxic or immunopotentiating These
include peptidoglycans Gram-negative endotoxin β-13-D glucans lipoglycans and
teichoic acids and mycotoxins (Jimenez 2000) In turn these microorganisms can mediate
the crystallization process These crystallizations can produce destructive effects Some
salts may crystallize or recrystallize to different hydrates which occupy a larger space and
exert additional pressure producing cracking powdering and flaking
(Jimenez and Laiz 2000)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
26 Review of Literature
211 Types of deterioration on mural paintings
The frescos represent a variety of ecological niches where primary colonization is
due to photoautotrophic and chemolithoautotrophic microorganisms followed by
secondary colonization due to heterotrophic bacteria that obtain nutrients from various
sources (metabolites of autotrophic bacteria airborne organic contamination animal faeces
and organic compounds in the paint layers themselves) Microbial-induced deterioration
processes cause structural as well as aesthetic damage to wall paintings such as the
discoloration of materials the formation of crusts on surfaces and the loss of material
(Sarro et al 2006 Osburn et al 2011) Halophilic bacteria and archaea were thought to
be found only in extreme environments like salt lakes or black smokers However it has
been shown that mural paintings and stones are a common habitat for extremely salt
tolerant and moderate halophilic (Ripka 2005) Microbial induced deterioration processes
can cause different kinds of alterations such as discolouration of materials the formation of
crusts on surfaces and the loss of material which leads to structural damage (Ripka 2005)
First of all microorganisms can cause severe problems due to the excretion of aggressive
metabolic products such as organic or inorganic acids Secondly material components can
be used as substrates for microbial metabolism Exoenzymes such as cellulases proteases
tannases beta-glucosidase produced by fungi and bacteria are responsible for hydrolysis of
cellulose and proteins Further examples are mechanical processes caused by swelling and
shrinking of slime or mycelia penetrating inside plaster of the painting resulting in loss of
cohesion and detachment of the paint layer (Rolleke 1996 Gurtner et al 2000)
Table-21 Microbial damage on mural paintings (Rolleke 1996)
S No Damage Microbial activity
1 Green brown red grey
surface layers (patinas)
Pigments produced by microorganisms (intra-or
extracellular) as chlorophyll and carotinoids
2 Dislodging of painting layers Use of organic binders as nutrient and energy
source
3 Acid attack of carbonates Acid produced by fungi or bacteria
4 Discolouration of pigments Redox-reactions induced by fungi and
bacteria
5 Loss of paint layer Growth of microorganisms deep into the plaster
6 Hydrolysis of synthetic
polymers Chemoorganotrophic activity of bacteria and fungi
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
27 Review of Literature
Discolorations are caused by excretion of pigments and microbiologically induced
reductionoxidation-processes (Krumbein et al 1990) Degradation of the bindings is
followed by reduction of stability Oxidation of ammonium and reduced sulphur
compounds results in acidification of the environment such as Sulphuric acid and the
variety of organic acids produced by the heterotrophs cause solubilization of calcareous
binding material and chelation of metal ions (Bock et al 1993) It is now well recognised
that wall paintings can be deteriorated by microorganisms (Ciferri 1999)The growth of
microorganisms essentially results in two types of damage aesthetic and structural
Aesthetic damage implies pigment discoloration stains and formation of a biofilm on the
painted surface Structural damage is observed as cracking and disintegration of the paint
layer formation of paint blisters and degradation of support polymers or of glues and
binders resulting in detachment of paint layer from the support The colonization of mural
paintings by bacteria and other microorganisms can have different causes Provided that
favorable environmental conditions occur nutrients for heterotrophic bacteria and fungi
can be available from metabolites of autotrophic bacteria from airborne contamination and
dripping water from animal faeces but also from organic compounds in the paint layer
itself
212 Methods of studying biodeterioration
It is now well recognized that wall paintings may be deteriorated by
microorganisms as established by several studies that linked the observed damage with the
microbial community present as reviewed by Ciferri (1999) Despite this knowledge a
reliable characterization of bacteria associated with such damage is often lacking To
obtain greater insight into the bacterial community involved in biodeterioration of mural
paintings three sites (from the necropolis at Carmona Spain and the Saint-Catherine
chapel of the castle at Herberstein Austria) were sampled In previous studies from these
sites 385 isolates were analysed by fatty acid methyl ester GC and representatives of
different fatty acid clusters were further studied by 16S rRNA gene sequencing
(Heyrman and Swings 2001) Several of these representative strains showed the highest
sequence similarity with members of the genus Arthrobacter (Heyrman et al 2005)
Jimenez and Samson (1981) analysed the microbial flora of a large fresco painted
in the late 1920s in the monastery ldquoSanta Maria de la Rabidardquo (Huelva Spain) exhibiting
two types of deterioration white efflorescence and green-to-black stains
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
28 Review of Literature
Tate and Rebrikova (1990) thought autotrophic nitrifying bacteria to be the first colonisers
of damaged frescoes and building materials in the cathedral of the nativity of the Virgin in
the Pafnutii-Borovskii monastery (Russia) The bulk of research on biodeterioration of
mural paintings has focused on explaining the observed phenomena by analysing the
microflora present Following this approach a precise characterisation of the
microorganisms using a polyphasic approach was never the first goal
Only a few studies included genomic fingerprinting (16S rDNA sequence analysis)
for the characterisation of bacteria associated with damage on mural paintings
[Rolleke (1996) Pinar et al (2001)] Previous studies based on culture-dependent
techniques showed that the flora present on frescos are fungi (predominant species of
Penicillium Aspergillus Cladosporium and Engyodontium) (Guglielminetti et al 1994)
bacteria (predominant species of Bacillus Arthrobacter Micrococcus Streptomyces and
Pseudomonas) (Heyrman et al 1999) cyanobacteria and eukaryotic algae (species of
Nostoc Lyngbya and Chlorophyceae) (Arino et al 1996 Calvo et al 1993) The killing
effect of an antimicrobial agent on a microorganism can be assessed in several ways
(1) Lethal activity may be expressed as the rate of killing by a fixed concentration
of drug under controlled conditions This rate is determined by measuring the number of
viable bacteria at various time intervals The resulting graphic depiction is known as the
time-kill curve Bacterial killing rates are in part dependent on the class of antibiotic and
the concentration of this agent With certain classes of antibiotics (eg aminoglycosides
and fluoroquino-lones) the rate of killing increases with increased drug concentrations up
to a point of maximum effect This is termed concentration-dependent bactericidal activity
In contrast the killing rates of szlig-lactam agents and vancomycin are relatively slow and
continue only as long as the concentrations are in excess of the MIC This rate of killing is
termed time-dependent bactericidal activity
(2) The minimal concentration of drug needed to kill most of the viable organisms
after incubation for a fixed length of time (generally 24 hours) under a given set of
conditions is the most common estimation of bactericidal activity and is known as either
the minimal bactericidal concentration (MBC) or the minimal lethal concentration (MLC)
It will be referred to in this document as the MBC Unfortunately the definition of the
MBC (999 killing of the final inoculum) is somewhat arbitrary and separates the
bacteria into two populations ndash a segrega-tion which might not have biological relevance
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
29 Review of Literature
The determination of the MBC moreover is so subject to methodologic variables that the
clinical relevance of MBCs is nearly impossible to assess particularly for certain pathogen
and drug combinations (eg Staphylococci and beta-lactam agents)
(3) The serum of a patient receiving an antibiotic may be tested against the
infecting microorganism This can be done using time-kill curve methodology (ie serum
bactericidal rate) or using dilution methodology (ie serum bactericidal titer) The
principles of these methods as well as the influence of biological and technical factors are
similar (Barry et al 1999)
213 Microbial flora associated with deteriorated mural paintings
A great deal of research has been done in this field mainly by using cultivation dependent
methods However by using culture-dependent methods only a very small proportion of
microorganisms can be obtained Far less than 1 of organisms in the environment can be
cultivated by standard cultivation techniques (Pace 1996) Recent studies have shown that
culture-dependent techniques yielded mainly sporeforming bacteria suggesting that plating
leads to an over estimation of the number of spore-forming bacteria A wide number of
investigations have shown that in addition to chemical and physical processes
microorganisms play a major role in degradation of objects of art such as paintings stone-
works wood paper masonry leather parchment glass and metal (Ripka 2005)
A) Bacteria
In general growth of diverse organisms on mural paintings is supported by
humidity slight alkaline pH values and the presence of organic and inorganic nutrient
sources (Weirich 1989) In mural paintings pigments are suspended in water or oil often
binders such as casein and milk are used and they are supplied on the damp lime plaster
(Ciferri 1999) The calcium carbonate formed on contact with air consolidates the
pigments Thus frescos contain mainly inorganic components While chemoautotrophic
nitrifiers and thiobacilli obtain their energy for growth by oxidizing ammonium and
reducing sulphur-compounds respectively heterotrophic bacteria and fungi depend on
organically bound carbon [Tate et al (1991) Lazar (1971) Petushkova et al (1986)
Jimenez et al (1981)] Thus primary colonization of photoautotrophic Cyanobacteria
chemolithoautotrophic nitrifying bacteria and sulphuric acid producing thiobacilli represent
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
30 Review of Literature
the first supply of organic matter The death and lysis of such bacteria promotes the
secondary settlement of heterotrophic bacteria and fungal populations (Calvo et al 1991)
Bacteria may derive from plants or pollen as many sequences obtained in this study
gave high score similarities with bacteria isolated from plants like Moraxella osloensis
Enterobacter cloace Enterobacter agglomerans and Pantoea endophytica Bacteria may
also derive from animal faeces like flies Bacillus Pseudomonas Aeromonas and Panteoa
(Ripka 2005) As Lazar and Dumitru (1973) reported studying mural paintings in a
Romanian monastery the genera Bacillus Arthrobacter and Pseudomonas have been
proved to produce salt efflorescences and were even considered to cause the blanching
phenomenon of frescoes (Jimenez et al 2000) Predominant bacterial genera are Bacillus
Streptomyces Arthrobacter Micrococcus and Pseudomonas [Weirich (1989)
Tate et al (1990) Arroyo et al (1997) Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
B) Fungi
It may be concluded that there is wide variety of fungal forms present on mural
paintings but Aspergillus and Alternaria were found dominating from all the experimental
sites next to them were Cladosporium Drechestera Fusarium Curvularia Chaetomium
Memnoniella Mycelia sterelai Pencillium Emericella Stachybotrytis Trichoderma
Phoma Monodictys Humicola and Epicoccum (Garg et al 1995)
The fungal genera most commonly found in lists of isolated taxa given in literature
are Alternaria Aspergillus Chaetomium Cladosporium Fusarium Penicillium and
Verticullum [Weirich (1989) Tate et al (1990) Guglielminetti et al (1994)
Garg et al (1995) Berner et al (1997) Ciferri (1999)] Some fungi having hard fruiting
bodies represented by sclerotia pycnidia perithecia cleistothecia and stroma could
organize themselves inside the painted layer Many fungal forms having such structures
were identified from our experimental sites viz Emericella nidulans A flavus
Chaetomium sp and Phoma sp etc These structures with little increase in humidity may
cause swelling in the paint film (Garg 1995)
Strains of species of Alternaria and Cladosporium both of them identified on the
mural paintings of the Palace of Schoumlnbrunn are the most common genera isolated from
stone and mural paintings in indoor environments with standard cultivation methods
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
31 Review of Literature
(Ventosa 2004) Saprophytic species of the genus Cladosporium are among the most
abundant fungi isolated in saltern samples Commonly isolated Cyanobacteria belong to
Nostoc and eukaryotic algae to Lyngbya and members of the Chlorophyceae such as
Chlorella Pseudococcomyxa and Pseudopleurococcus [Gorbushina et al (1987)
Calvo et al (1993) Arino et al (1996)]
They grow optimally on media with low water activity due to high salt or sugar
concentrations seem to propagate 70 vegetatively in the salterns and are thus
halotolerantosmotolerant species rather than simple flush-through occurrences
Cladiosporum herbarum was frequently isolated from hypersaline waters dead and dying
plant material air soil food fruit cereals paint and textiles (Ventosa 2004)
C) Algae
Most of the painted areas in temperature climate became covered with green algae
(Pleurococcus Protococcus and Trentopholia) while under tropical conditions blue green
algae of the genera Oscillatoria and Sytonema predominated (Garg 1995) The main
factors which contribute to the growth of algae on wall paintings are the presence of
moisture in the plaster as well as availability of visible light These conditions are quite
prevalent in the tropical climate but in temperature regions also algal growth on wall
paintings have been reported [Tonolo et al (1961) Pietrini et al (1991)]
D) Actinomycetes
Usually literature refers to specific aspects eg the occurrence of cyanobacteria
and algae in caves with natural openings to sunlight or those with artificial lighting fungi
and so forth Actinomycetes have been considered to be mainly confined to soils where
they find their natural habitat but despite intensive studies there are still many gaps in our
knowledge of the role played by actinomycetes in soil processes and biodegrations of
murals cave paintings (Groth et al 1999) In addition halophilic bacteria actinomycetes
and cyanobacteria are also capable of growing on salt-affected mural paintings
(Karbowska 2003)
Monte and Ferrari (1993) reviewed the mechanisms of biodeterioration in tombs
and underground churches The role of actinomycetes in the deterioration of frescoes in
hypogean environments was stressed by Agarossi et al (1985) Monte and Ferrari (1993)
Giacobini et al (1987) described the serious damage suffered by a whole series of famous
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
32 Review of Literature
frescoes in underground environments Actinomycetes were isolated from these mural
paintings located in crypts caves and tombs About 200 strains of actinomycetes were
isolated 60 of which were identified The most frequent species were Streptomyces albus
S cinereoruber S griseolus S vinaceus and some members of the Nocardia genus
Heterotrophic bacteria and actinomycetes were the most abundant microorganisms
on the frescoes of Etruscan tombs (Agarossi et al 1985) Bettini et al (1977) studied
some of the oldest Etruscan tombs (7th to 4th century BC) and found white-grey patinas
and spots from streptomycetes in the mural paintings They related the biodeterioration to
the microclimatic conditions (eg lower temperatures high RH) Monte and Ferrari (1993)
considered that colonization of the mural paintings was the result of selective competitive
and inhibitory dynamics among different microorganisms under different and changing
environmental conditions The pigments excreted by some actinomycetes were responsible
for the violet stains found on the walls of tombs in Tarquinia Similar stains were observed
in one of the Roman tombs the Circular Mausoleum the Necropolis of Carmona Spain
from which a Streptomyces sp producing violet pigments in culture media was isolated
214 Identification of biodeteriogens
The possibility of pigments and biodeteriogens identification in frescos and stone
monitoring is offered mostly by vibrational spectroscopy infrared thermography laser
induced fluorescence (LIF) laser induced breakdown spectroscopy (LIBS) XRF (X-Ray
Fluorescence) IR and UV emission Among them laser based methods allowing for in
situ or remote characterization of artwork surface were applied successfully for
prospecting diagnosis and maintenance (Colao et al 2005) The rep-PCR fingerprinting
of the isolates allowed determination of their genotypic diversity Studies that have
compared rep-PCR genomic fingerprint analysis with DNAndashDNA relatedness studies have
shown that the two techniques yield results that are in close agreement [Nick et al (1999)
Rademaker et al (2000)] These studies therefore suggest that rep-PCR fingerprinting can
be used as a genomic screening method to differentiate at the species level and to select
representatives for DNAndashDNA reassociation experiments (Heymann et al 2003)
The characterisation of bacteria was for example often limited to isolation from
group-specific media followed by microscopy [Sorlini et al (1987) Weirich (1989)
Tate et al (1990) and in more recent studies to morphological and physiological
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
33 Review of Literature
characteristics including miniaturised and automated systems such as API and BIOLOG
[Arroyo et al (1997) Jimmenez et al (2000) and Laiz et al (2000)] or to
chemotaxonomic characteristics [Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
Wagner et al (1994) demonstrated that conventional microbiological efforts can
fail to isolate all microorganisms present in natural samples DNA-based techniques used
to identify microorganisms have revealed only a smaller fraction of bacteria isolated from
artworks (Ward et al 1990 Rolleke et al 1996) Bacterial identification using molecular
techniques especially those including the sequencing of genes coding for ribosomal
16S rRNA is very important to study bacterial communities found on artefacts One such
method is Denaturing Gradient Gel Electrophoresis (DGGE) of PCR-amplified gene
fragments coding for rRNA (Muyzer et al 1993) that allows the separation of partial
16S rDNA amplified fragments of identical length but different sequence due to their
different melting behaviour in a gel system containing a gradient of denaturants
(Jimenez 2003)
Total genomic DNA was purified for 16S rRNA gene sequencing and rep-PCR
using a slight modification of the method of Pitcher et al (1989) as described by
Heyndrickx et al (1996) rep-PCR genomic fingerprinting was performed with the REP-
and (GTG)5 primers (Versalovic et al 1994) using the PCR conditions described
previously by Rademaker et al (1997) Electrophoresis and pattern analysis were further
performed as described by Heyrman et al (2003) 16S rRNA gene sequencing and
phylogenetic analysis were performed as described by Heyrman and Swings (2001)
Phylogenetic trees were constructed using the BioNumerics software (Applied Maths) by
applying the neighbour-joining and maximum-parsimony methods on a multiple alignment
similarity matrix The stability of relationships was assessed by a bootstrap analysis of
1000 datasets For determination of the G+C content and levels of DNAndashDNA
hybridization approximately 1 g biomass was harvested from agar plates DNA was
purified by using a combination of the protocols of Marmur (1961) and
Pitcher et al (1989) as described by Logan et al (2000) The G+C content of the DNA
was determined by HPLC (Mesbah et al 1989) using the further specifications given by
Logan et al (2000) DNAndashDNA hybridization experiments were performed using a
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
34 Review of Literature
modification of the microplate method of Ezaki et al (1989) as described by
Willems et al (2001)
215 Preservation and conservation
Nowadays the conservation and preservation of our cultural heritage is one of the
world main concerns particularly in Europe The increasing need for non-destructive
investigation tools has become a major issue as sampling is in most cases restricted in
view of the value or the uniqueness of the object Artworks as wall paintings in buildings
and monuments of historical interest are affected by environment physical (temperature
and humidity) and biological factors (biodeteriogens) and by human (pollutant releases)
impact and therefore modified over the time The term ldquoconservationrdquo may have many
different meanings in different fields Every intervention directed to the restoration and
safeguard of works of art is commonly considered as a conservation treatment For
example conservation can involve the cleaning procedures set up by chemists or the photo
documentation of the preservation of historical memory For the appropriate conservation
of works of art even the lighting systems in a museum or the control of the visitorrsquos
movements in a site should be monitored Chemical degradation which induces the flaking
of paintings and deterioration from rain wind dust and other environmental causes is
mainly responsible for the weakening of the porous structure and the surface layers of the
materials used in works of cultural heritage (Colao et al 2005)
216 Conservation history
Wall paintings are an integral part of monuments and sites and should be preserved
in situ Many of the problems affecting wall paintings are linked to the poor condition of
the building or structure its improper use lack of maintenance frequent repairs and
alterations Also frequent restorations unnecessary uncovering and use of inappropriate
methods and materials can result in irreparable damage Substandard and inadequate
practices and professional qualifications have led to unfortunate results It is for this reason
that an appropriate document covering the principles of proper conservation-restoration of
wall paintings is necessary
The Venice Charter (1964) has provided general principles for the conservation-
restoration of cultural heritage The Amsterdam Declaration (1975) introducing the
concept of integrated conservation and the Nara Document on Authenticity (1994) dealing
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
35 Review of Literature
with cultural diversity have expanded these principles Taking into account these and
additional relevant contributions such as the ICOM-CC Code of Ethics (1984) Document
of Pavia (1997) and ECCO Professional Guidelines (1997) the aim of this document is
to provide more specific principles for the protection preservation and the conservation
restoration of wall paintings This document therefore reflects basic and universally
applicable principles and practices and does not take into account particular problems of
regions or countries which can be supplemented at regional and national level by
providing further recommendations where necessary
217 Preservation techniques of the mural paintings
The removal of fat salts varnishes and pollutants from the surfaces of the works
of art are mostly done by chemical and mechanical methods At the end of the 19th
century the practices of restoration methods that do not inhibit further future interventions
was considered acceptable During the 1960s several chemicals such as polymeric resins
were synthesized and applied as a consolidation or protection agents The accepted idea
was that these substances could be removed at any time leaving a completely unaltered
substrate On the basis of origin archaeological objects can be classified as follows
(Carretti 2005)
1 Inorganic It includes siliceous and nonsiliceous materials Archaeological materials
produced from stones terracotta ceramics and glass can be included under siliceous
materials whereas objects made of metals can be included under nonsiliceous inorganic
materials Again metal objects can be classified as ferrous metals and non-ferrous metals
Objects made of iron are termed as ferrous metal objects whereas metal objects made from
other than iron is termed as non-ferrous metal objects
2 Organic It includes archival and anthropological materials Again archival materials
include paper bhojapatra tadapatra textiles wooden objects miniature paintings whereas
anthropological objects include bone and ivory leather feather and fur etc
In the past restoration of paintings and other old artwork often involved application
of acrylic resins to consolidate and protect them One of the most important tasks for
modern restorers is thus to remove these layers because it turns out that acrylic resins not
only by drastically changing the optics of the treated artwork but in many cases they
accelerate their degradation The scientists use an oil-in-water microemulsion with the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
36 Review of Literature
organic solvent para-xylene as the oil component The matrix makes the cleaning agent
viscous so that it cannot enter very far into the pores of a painting (Carretti 2005)
Nanoparticle treatment is the logical evolution of the Ferroni-Dini method
Dispersions of kinetically stable Ca (OH)2 nanoparticles in non-aqueous solvents solved
most of the drawbacks of the microsized powders Stable dispersions of calcium hydroxide
have been successfully applied (replacing polymers) as fixatives to re-adhere lifted paint
layers during many restoration workshops in Italy and in Europe as a consolidant The
FerronindashDini method (two steps the application of a saturated solution of ammonium
carbonate (NH4)2CO3 and the treatment with a barium hydroxide solution Ba(OH)2 also
called the barium method has long been the acknowledged method for the removal of
salts that threaten paintings reinforcing at the same time the porous structure However
commercially available carbonates and hydroxide powders have dimensions of several
micrometres much larger than the pores on the paint surface This means they donrsquot
penetrate the painting well and there is also a risk of damaging the artwork by a white
glaze forming on the surface (Berger 2006) Restoration should provide the reinforcement
of the porous structure and the consolidation of the surface layer of arte facts A few
simple principles can be considered to define the most appropriate restoration method
1) The treatment should be reversible so that one can revert to the original status of the
work of art at any desired time
2) All the applied chemicals must ensure the maximum durability and the chemical
inertness
3) The applied chemicals must invert the degradation processes without altering the
chemical composition of the artefacts and their physico-chemical and mechanical
properties (Baglioni 2006)
218 Commercial preservative used for preservation of mural paintings
Cleaning was done using soft brushes vacuum cleaner and Gumma paine (dough)
a natural latex sponge Areas near the window were very dirty with black soot and were
cleaned with micro fibrous cloths moistened with synperonic N (surfactant alkyl phenol
ethoxylate based on nonyl phenol) and neutralized with clean water In several places the
paint layers had separated from the substrate (exfoli-ation) In that cases loose paint flakes
were stuck back using Paraloid B72 (10 solution in ethanol) as sparingly as possible
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
37 Review of Literature
Paraloid was injected with syringe behind the exfoliated area twice pushed and held back
with Melinex (polyester film) until fixed on the third application (Bionda et al 2002)
In a period of significant growth of molds and intensive efforts to stop the mold
contamination some of the lines of certain paintings were obscured or faded Solutions of
ethanol formalin 91 and Thiabendazole (TBZ) were used but they were not very
effective Para-formaldehyde fumigation was adopted beginning in 1981 to establish an
emergency treatment sensitivity of microorganisms from studied samples was tested
against Desogen by adding 1-3 (v v) in serial dilutions The best concentration
3 (vv) was applied with a brush to prevent spreading of the spores In order to overcome
the problem of fungal attack suitable fungicides carbendizeme or kiroxy-I or 5 solute of
N formaldehyde can be used Shellac solution in spirit or 2 solution of polyvinaycletate
in toluene can be used as preservative and consolidantsTo control insect and fungal attack
fumigants like pyrethrum DDT or 5 solution of sodium penta chlorophenate in kerosene
oil 2 to 5 solution of PVA in toluene or 2 to 5 solution of paraloid B-72 in toluene or
acetone be used (Miura 2009) Microclimatic conditions constitute a critical factor in the
conservation of cave paintings The unstable microclimatic condition is one of the factors
that always affect the state of conservation of mural paintings In the environmental-
monument system knowledge of the functional environment and climatic conditions of the
surroundings are necessary for the identification of causes of decay (Singh 2011)
Furthermore the risk of formation of indoor bioaerosols in residential and public
buildings (offices schools museums etc) has attracted interest in the last years due to
socio-economic as well as sanitary reasons (Ripka 2005) Thus it is important in aspects of
health and maintenance of Cultural Heritage to analyse the complete microflora to further
develop biocides for harmful microorganisms and methods for restoration of damaged
objects of art The biocidal testing was carried out on one representative algal species of
the two classes of algae viz Chlorococcum sp (green) and Chroococcus sp (blue-green)
found to be common in all the samples Efficiency tests were carried out both in liquid as
well as solid media containing algal suspensions by adding a biocide solution of known
concentration and determining the growth of the microorganism after the incubation
period The biocides used for the past studies were
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
10 Review of Literature
India has one of the greatest traditions of painting of the ancient world Murals and
miniature are the two different forms of arts which intrinsically related to Indian painting
tradition The earliest evidence of murals is the beautiful frescoes painted on the caves of
Ajanta and Ellora also on the Bagh caves and Sittanvasal The oldest mural paintings date
is about 3000 years BC (Sasibhooshan 2006)
The number of wall paintings in each state of India is very large and they are
suffering from all types of deterioration and damage but in comparison facilities for their
preservation are much too small This is a very serious problem The main objective of the
present study is to develop a protective bio-based gel (Rajagopalan 2008)
24 North Indian murals
North India has a rich heritage of Mural paintings even before the Mughal period
The murals at the Vishnu Temple located at Madanpur in Lalitpur district of Uttar Pradesh
of 12th century AD reveals the skillful hands of the painters In Eastern India there are
many evidences of wall and panel paintings describing Buddhist and non- Buddhist
themes In Arunachal Pradesh and Tripura sublime mural works have been found which
needs further study Ladakh is known for its wall paintings in Alchi and Hemis
monasteries made on 11th-12th century and the Spiti Vally in Himachal Pradesh is known
for its Buddhist paintings in the Gomphas of Tabo Monastery (Havell 1982)
Ajanta is known to be the fountain head and inspiration of Buddhist paintings
across the whole of Asia There are fragments of paintings of the time of Ajanta which
survive at many Buddhist cave sites including Pitalkhora near Ellora in Maharashtra The
magnificent Kailashnath temple had been hewn out of a mountain at Ellora in the 8th
centuryThe Kashmiri style was mainly responsible for the lovely wall paintings still seen
in the beautiful monasteries at Alchi Mangyu and Sumda in Ladakh in the Tabo
monastery in the Spiti valley and in the Nako monastery in Kinnaur district Himachal
Pradesh On the western edge of the trans-Himalayan plateau in Spiti is the monastery
complex of Tabo This appears to be one of the first among the 108 monasteries built by
Yeshe It is dated around 996 AD There are also paintings of the late 9th century in the
Jain caves at Ellora (Spink 2009)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
11 Review of Literature
Figure-23 Ajanta caves
Figure-24 Mural Painting of Ajanta caves
Ellora Caves Maharashtra belong to the highest achievements of mankind both
regarding the engineering skills and arts Some 2000 years ago Pitalkhora Caves
(Maharashtra) were among the largest temple complexes in India These 11 - 14 caves
were created in 250 BC - 4th century AD In 4th century AD temples were adorned with
beautiful murals especially fine paintings have been preserved on columns of Cave 3
Traces of murals are in Cave 6 as well Already the oldest group of caves here - Buddhist
caves from 630 - 700 AD - contain paintings of Buddhist panteon Remnants of paintings
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
12 Review of Literature
are seen in the most beautiful temple - Cave 16 Kailasanatha circa 760 - 860 AD Some
Jain temples - Cave 32 (Indra Sabha) Cave 33 - contain remnants of valuable murals from
800 - 1000 AD - this artwork marks the end of ancient period in the Indian art and
beginning of medieval art (Baskaran 1975)
Figure-25 Ellora caves
There are surviving mural paintings from the 17th century onwards in Rajasthan
The verdant Pahari hills saw the finest continuation of the tradition of murals in India The
18th and 19th century paintings on the walls of the Rang Mahal in Chamba are among the
best surviving examples of Pahari murals The 18th century paintings on the walls of the
Viranchinarayan Temple at Buguda are some of the finest surviving murals of that period
in India
Figure-26 Paintings on the walls of the Rang Mahal in Chamba
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
13 Review of Literature
The most important sites of rock paintings in North India are at Bimbetka Gwalior
Tikla Ayra Bhanpura Rampura Singhauli Bhojpur Adamgrh Delware and Mirzapur
In South India they are found at Mehaboob Nagar (Andhrapradesh) Edakkal Marayoor
Perimkadavila (Kerala) Mallampadi (Tamilnadu) and Bellary (Karnataka)These
paintings were considered as the early models of mural paintingsThe mural painting of
Sittannavasal Badami Lepakshi Tanjore Vijayanagar and Kerala has a lot of similarities
(Sasibhoosan 1987)
25 South Indian murals
South India also got rich tradition of mural paintings In the reign of Cholas
Vijayanagaras and Nayakas this art reached the climax The Deccan art of Bijapur
Hyderabad and Golconda schools were influenced by the Mughal traditions and later by
European idiom Maratha murals are also shaped under the Mughal traditions and
employed oil as medium The Mural art of Kerala vividly depicted on the walls of temples
and monuments show the traces of European affinity In Tamil Nadu almost all the extent
examples of frescos have been done on rock surfaces and stone walls This is a crucial
factor in determining the quality of frescos (Havell 1982) The ceiling of the Virupaksha
temple in Hampi is covered with paintings of the 15th century The paintings on the ceiling
of the mandapa of Lepakshi temple are some of the finest mural paintings of the medieval
period in India Legends associated with Siva and Parvati Krishna and Rama were painted
on the walls of palaces and temples in Kerala from the 16th to 19th century Mural
paintings were made on the walls of all the palaces within the magnificent Orccha fort The
Raj Mahal was completely adorned with mural paintings of the 17th century
Figure-27 Virupaksha temple in Hampi
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
14 Review of Literature
Figure-28 Ceilings of Virupaksha temple Hampi
The murals on the walls of the navaranga (the central pillared hall) depict stories
from Bhagavatha and are excellent examples of 19th
century Mysore paintings The
Mallikarjunaswamy temple on the hill is one of the Panchalingas of Talakad and the
temple has a beautiful mural painting on the wall of the temple The Dariya Daulat Bagh
has excellent mural painting (Sasibhoosan 1987)
Figure-29 Paintings on the walls of Jagan mohan palace Mysore
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
15 Review of Literature
Figure-210 Painting of Raja woodeyar era
Kerala mural paintings are the frescos depicting mythology and legends which are
drawn on the walls of temples and churches in South India principally in Kerala Ancient
temples churches and palaces in Kerala South India display an abounding tradition of
mural paintings mostly dating back between the 9th to 12th centuries The murals of
Thirunadhikkara Cave Temple (now ceded to Tamilnadu) and Tiruvanchikulam are
considered the oldest relics of Keralarsquos own style of murals Fine mural paintings are
depicted in temples at Trikodithanam Ettumanur Vaikom Pundarikapuram
Udayanapuram Triprangode Guruvayoor Kumaranalloor Aymanam the Vadakkunathan
temple in Trichur and the Sri Padmanabhaswamy temple at Thiruvananthapuram Other
mural sites are in the churches at Edappally Vechur Cheppad and Mulanthuruthy and at
palaces such as the Krishnapuram Palace near Kayamkulam and the Padmanabhapuram
Palace
Figure-211 Kerala murals
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
16 Review of Literature
Figure-212 Murals paintings of Kerala temples
There are wall paintings in Badami in the Bijapur district Karnataka Some
excellent paintings exist in the Jain caves at Sitanavassal in Puddukkottai District of Tamil
Nadu Tamil Nadu gave exuberant and glorious expression to themes relating to Siva in the
temples of Panamalai and Kailashanatar in Kancheepuram In the 9th century Jain cave of
Sittannavasal in Tamil Nadu there is a marvellous lotus pond painted on the ceiling In
the heart of the Brihadeeswara temple in Thanjavur Tamil Nadu protected by massive
walls of stone are the finest paintings of the theme of Siva ever painted towards the end of
the 10th century (Sivaramamurthi 1992)
Figure-213 Kancheepuram Mural paintings
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
17 Review of Literature
Figure-214 Sculpture of Mahabalipuram
26 Methods of mural painting
In the history of mural several methods have been used The Buon fresco technique
consists of painting in pigment mixed with water on a thin layer of wet fresh lime mortar
or plaster The pigment is then absorbed by the wet plaster after a number of hours the
plaster dries and reacts with the air it is this chemical reaction which fixes the pigment
particles in the plaster After this the painting stays for a long time up to centuries in fresh
and brilliant colors A Secco painting is done on dry plaster The pigments thus require a
binding medium such as egg (tempera) glue or oil to attach the pigment to the wall
Mezzo-fresco is painted on nearly-dry plaster which is defined by the sixteenth-century
author Ignazio Pozzo as ldquofirm enough not to take a thumb-printrdquo so that the pigment only
penetrates slightly into the plaster Ancestral Hopi village archaeologists found that
fourteen kivas had painted murals and multiple layers of murals on the walls some with up
to twenty-seven layers of murals (Saturno 2006)
The colors used in painting are generally obtained from plants and minerals
Among them only such colors which are lime resistant are suitable for mural painting The
selection of proper colors for a mural painting is an important part of the work as the
longevity the painting depends on it Only mineral colors are preserved for a long time
which could be the reason for use of those colors in early days As per ldquoShilpa ratnardquo and
ldquoAgnipuranardquo the colors used in mural painting are white black red yellow blue and
green Yellow and red are from yellow ochre and red ochre Blue is generally indigo or
china blue White is the prepared wall and black is the carbon soot Mural paintings have
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
18 Review of Literature
survived centuries only on account of the identification and use of those colors which does
not have any reaction with lime (Miraseth 2006)
Originally three types of brushes were made and used flat medium and fine Flat
brushes were made from hairs behind calfrsquos ear the medium from the bottom of goats
belly and the fine brush from delicate blades of grass However in due course of time and
change use of easily available brushes from commercial market and shading of the
original colours can be distinctively noticed The use of blue colour is also noticed over the
passage of time The paintings have been brought down from the walls to plywood cloth
paper and other frames for easy to make and use purposes (Chakarabarti 1980)
27 Themes of mural painting
The subjects and themes in the murals are centered on the Hindu pantheon of Gods
and Goddesses drawn from description in the invocatory verses or Dhyana Slokas More
common representations are of Vishnu in different incarnations Ganesha and
manifestations of Siva We see murals in the Pallimanna Siva Temple devoted to Siva-
Parvatirsquos marriage the Ramayana Story being narrated on the walls of the Mattancheri
palace in the Sankara Narayana the Mahabharata is retold Murals are various scenes from
the Hindu epics and also the frolics of Lord Krishna
It would be interesting to bring into account the influence of the mural paintings on
Christianity On various churches like the St Georgersquos Orthodox Church has Christian
murals bringing out biblical characters and narrating stories from the scriptures Mar
Sabore and Afroth Church at Akapparambu in the outskirts of Ernakulam also have murals
of scenes from the bible Interestingly StMaryrsquos Church at Kanjoor has on both sides of its
entrance a battle scene between the armies of Tipu Sultan and of the English East India
Company It is also apparent that the history of Kerala Murals has its origin in the temple
walls and thus a study of Kerala Murals is not complete without pondering on the
architecture of Kerala its association with the murals (Warrier 2011)
28 Technique used in mural paintings
Indian murals executed on walls of caves structural temples walls of palaces were
based on highly developed techniques Mural painting is a composite structure of these
three basic layers the support the ground and the pigment layer In case of wall painting
the wall itself is the support This is followed by the layer or layers of plaster which
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
19 Review of Literature
constitute the ground The pigment layer is the one which contains the picture The support
is the wall which may be rock surface in a cave or a structural one These stone surfaces
which serve as carriers are rough or uneven This unevenness is itself an advantage as it
provides ldquotoothrdquo to hold the plaster on the surface The uneven surface of the wall has to be
made uniform with layers of plaster in successive gradation of fineness There is generally
one layer of rough plaster followed by one or more layers of fine plaster Ground or plaster
is a term used to mean the surface material of a wall or building which is applied as a
plastic mass made by mixing certain materials with water letting the mass set by drying
carbonation or hydration The active or setting components of plaster are commonly clay
which sets by drying lime which sets by carbonation gypsum and pozzolana which sets by
hydration (Mini 2010)
There are different mixtures for rough plaster In all the mixtures clay limestone
lime and shells in powdered form serve as the matrix The particles of which are held
together by the organic materials like gum glue extracts from barks etc are in fact
adhesives The fine plaster layer requires more careful preparation because it is the layer on
which the pigments are laid to make the picture ldquoShilparatnardquo suggest a mixture of conch
Oyster shells or white clay with gum of neem or slaked lime and coconut water Here the
consolidation is effected by the carbonation of slaked lime ie it absorbs carbon dioxide
from air and becomes carbonate Mural paintings were lime-washed from the 17th until the
beginning of 19th century A few paintings in vaults were never lime-washed for example
at Taby and Floda painted by the medieval painter Albertus Pictor (Mini 2010)
All the paintings have certain basic common characteristics There has to be a wall
or rock surface called support over which the artist goes to work A plaster base called
ground of varied thickness is laid on the support The ground may consist of one or more
layers The strength and life of the whole mural depended up on this ground over which the
painting was done It is the process of applying the final painting on the ground determines
the character of the mural whether it is fresco or tempera The mural painting is done
usually by creating wall surface free of any previous oil or paint by using solvent or by
sand blasting The brick wall is first plastered with mixture of lime and sand in the ratio of
12 A mixture of egg yolk vinegar oil colour is used in dry plaster
There are at least six stages before a Kerala Mural Painting is complete Lekhya
Karma is the first stage where sketching by pencil or crayon is done The second stage is
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
20 Review of Literature
the Rekha Karma which enhances the outlines of the sketching done The third stage called
Varna Karma breathes life into the painting with its colours Here all colours are
appropriately filled in The colouring of the human figures is done according to the
characters and their common virtues The divine and noble characters (Saatvik) are painted
in green those inclined towards power and wealth (Raajasik) is painted in shades of red
lowly mean characters (Tamasik) in white and demons in black In the fourth stage or the
Vartana Karma shading is done Fifth stage called the Lekha Karma brings us to the final
outline of the painting which is usually in black The final and the finishing touches stage
are called Devika Karma (Warrier 2011)
29 Dyes used in mural painting
Indians have been considered as fore runners in the art of natural dyeing Natural
dyes find use in the colouring of textiles drugs cosmetics etc Owing to their non-toxic
effects they are also used for colouring various food products In India there are more
than 450 plants that can yield dyes In addition to their dye-yielding characteristics some
of these plants also possess medicinal value Though there is a large plant resource base
little has been exploited so far Due to lack of availability of precise technical knowledge
on the extracting and dyeing technique it has not commercially succeeded like the
synthetic dyes (Siva 2007)
The color materials on the mural paintings in ancient India were derived from the
natural materials like terracotta chalk red ochre and yellow ochre mixed with animal fat
The dyes for painting is prepared such as white from lime Black from carbon soot of
lamps Red and yellow from minerals Blue from indigo ferra Deep red from lac A fine
coating of resin is done after the painting in order to make a shining appearance Egg yolk
and vinegar was mixed with oil colors and painted on dry plaster (Krishnakumar 1999)
Although plants exhibit a wide range of colours not all of these pigments can be
used as dyes Some do not dissolve in water some cannot be adsorbed onto fibres whereas
others fade when washed or exposed to air or sunlight It remains a mystery why plants
reward us with vibrant dyes India has a rich biodiversity and it is not only one of the
worldrsquos twelve mega diversity countries but also one of the eight major centres of origin
and diversification of domesticated taxa It has approximately 490000 plant species of
which about 17500 are angiosperms more than 400 are domesticated crop species and
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
21 Review of Literature
almost an equal number their wild relatives Thus India harbours a wealth of useful
germplasm resources and there is no doubt that the plant kingdom is a treasure-house of
diverse natural products One such product from nature is the dye (Siva 2007)
Many natural dyestuff and stains were obtained mainly from plants and dominated
as sources of natural dyes producing different colours like red yellow blue black brown
and a combination of these Almost all parts of the plants like root bark leaf fruit wood
seed flower etc produce dyes It is interesting to note that over 2000 pigments are
synthesized by various parts of plants of which only about 150 have been commercially
exploited Nearly 450 taxa are known to yield dyes in India alone of which 50 are
considered to be the most important ten of these are from roots four from barks five from
leaves seven from flowers seven from fruits three from seeds eight from wood and three
from gums and resins Some important dye-yielding plant habitats their distribution and
colouring pigment (Siva 2007)
The dye is generally prepared by boiling the crushed powder with water but
sometimes it is left to steep in cold water The solution then obtained is used generally to
dye coarse cotton fabrics Alum is generally used as a mordant Flowers of Butea
monosperma (Lam) Taubert yield an orange-coloured dye which is not fast and is easily
washed away For the purpose of colouring the material is steeped in a hot or cold
decoction of the flowers A more permanent colour is produced either by first preparing the
cloth with alum and wood ash or by adding these substances to the dye-bath The dye
indigo is produced by steeping the plant in water and allowing it to ferment This is
followed by oxidation of the solution with air in a separate vessel Mallotus philippinensis
muell yields an orange colour used for dyeing silk and wool To prepare the annatto dye
from B orellena the fruits are collected when nearly ripe The seeds and pulp are removed
from the mature fruit and macerated with water Thereafter they are either ground up into
an lsquoannatto pastersquo or dried and marketed as annatto seeds Sometimes when the seeds and
pulp are macerated with water the product is stained through a sieve and the colouring
matter which settles out is collected and partially evaporated by heat and finally dried in
the sun (Sowbhagya 2002)
The predominant colors used in rock art and cave art are black (from charcoal soot
or manganese oxide) yellow ochre (limonite) red ochre (hematite or baked limonite) and
white (kaolin clay burnt shells powdered gypsum or powdered calcium carbonate) All of
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
22 Review of Literature
theses pigments may be used on leather or raw hide as well Early cave art in Seminole
Canyon was monochromatic in red and as culture grew more sophisticated the color
palette expanded Blue Orange Brown Green and Purple are the most common colours
used in Ajantha murals White Pink Gold are occasionally represented mineral earths
containing ferric oxide and copper carbonates were used as source of red yellow and green
colours There is also evidence to establish that root of Rubia cardifolia and leaves of
Indigofera tinctoria were used as source for red and blue colours (Nayer et al 1999)
Many colors of pigments were obtained from both organic and inorganic sources in
ancient times and used to paint various surfaces such as braintan leather clothing and
accoutrements rawhide the human body etc Blue color was obtained from powdered
azurite and lapis duck manure and certain clays Fine Blue-green clay was obtained from
deposits near Mankato Michigan Organic sources of blue include Turkeys Tail a
greenish blue polypore that grows on dead decaying wood (not tannish ones) Native
Americans get Indigo from either Guatemala or Ecuador which was traded well up onto
Kansas long before the Spanish ever set foot here American Indigo has purple tones to it
but IndianJapanese indigo has green tones Berries and crushed flowers were also used to
obtain blue color by rubbing the plant material directly on the leather
An organic source of red was Cochineal It was native west of the Mississippi and
is produced from the bodies of small insects that grow on the prickly pear cactus Ladys
Bedstraw gives a good vermillion red color Harvest the roots dry them out clean the mud
etc off of them and then grind the roots really fine then soak them to extract the red
coloring The key here is drying the root first Blood was also used as red pigment Pucoon
roots also yield a red pigment (Smith 2002) Red ochre the reverse original red colours are
due to variations in iron oxide (or) calcite content and to redox conditions in the firing
produced Brown coloured ceramics owe their colour to maghemite and must be
considered as a fabrication defect due to the position of the ceramic piece in a zone where a
reducing atmosphere prevailed in the course of firingRed pigments were produced from
iron oxides like hematite or limonite and from ochre Hematite was the most frequently
used mineral It occurs in the form of aggregates of small red crystals or in the form of
bigger black crystals which are difficult to crush white was obtained mostly from
kaolinite or illite (Clottes et al 1990)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
23 Review of Literature
210 Biodetoriation of mural paintings
Historic items often contain natural biodegradable materials and have histories of
exposure to moist conditions These two conditions make them amenable to microbial
attack Microbial colonization may damage the building or the cultural asset
(Salonen 2001) Biodeteriogens are organisms involved in deterioration of artifacts They
are very specific for each type of artifact in accordance with its chemical structure and
environment They also have different nutritional requirements and act directly or
indirectly on the substrate The adhesion of microorganisms to a substrate is the result of
cell hydrophobicity and of excreted polymeric substances contained by sheaths capsules
and slimes (Colao 2005)
The surviving wall paintings and decorations in subterranean environments around
Malta are rather scarce (Buhagiar 1986 1993 1998) These include those at St Paulrsquos
Catacombs (Zammit 2008) St Agatharsquos Crypt and Catacombs (Camilleri 2001)
San Catald Catacombs Tac-Cghaqi Abbatija tad-Dejr (Buhagiar 1993) all in Rabat the
cave-sanctuary in Mellieħa (Buhagiar 1987) and the Ħal Saflieni Hypogeum in Paola
(Pace 2000) Previous studies conducted on wall paintings and decorations in Maltese
Palaeo-Christian Catacombs have involved their manufacturing techniques (Muscat 2005)
However to date limited systematic studies have been conducted into the biodeterioration
in Maltese Palaeo- Christian Catacombs The only such studies ever conducted in Malta
concerned the biodeterioration of works of art in catacombs have been carried out at St
Agatharsquos Crypt and Catacombs in Rabat (Zammit et al 2008 Psaila 2006)
Microorganisms can be responsible for the destruction of monuments buildings
and cultural heritage assets including the decay of concrete cement stones mural
paintings etc These microorganisms are not only related with biodeterioration but water-
damaged indoor building materials are frequently colonized by complex bacterial
communities and may emit mixed bioaerosols into the indoor air (Jimenez 2000) It is
well known that mural paintings are colonized by micro-organisms and can be severely
damaged by such growths (Ciferri 1999) A large number of fungal (gt50) and bacterial
taxa (70) have been detected in indoor environments Over 50 bacterial species and 14
genera novel to science were reported in the past 10 years from indoor air and historic
items indicating bacterigravea in these enviroments are as yet only fragmentarily known
(Salonen 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
24 Review of Literature
Traditionally the study of microflora which causes this biodeterioration was based
on classical cultivation methods that were mainly useful to study the physiological
potential of microorganisms but do not provide information on all microbial communities
to be found in excavated artifacts Indeed many studies using culture-independent
techniques which cultivate microorganisms from different environments may often
represent only minor components of the microbial community as a whole It is generally
accepted that cultivation methods recover less than 1 of the total microorganisms present
in environmental samples (Ward et al 1990 Amann et al 1995) Hence microbial
investigations based only on cultivation strategies cannot be regarded as reliable in terms
of reflecting the microbial diversity present in objects of art (Osburn et al 2011)
Early workers suggested that the presence of living microorganisms on stone
increased its susceptibility to damage through their water-binding capacity It has recently
been reported that the mineralogy porosity surface roughness and capacity to collect
water and organic materials control its bioreceptivity and tendency to biodeterioration
(Diakumaku 1995) In addition environmental factors as temperature light pH and
relative humidity affect the number and type of colonising species (Tiano et al 1995) and
hence the progress of colonisation Biofilms on decayed stones consist on mixed microbial
populations embedded in a polymeric matrix Fungi algae filamentous and unicellular
bacteria are found in these complex communities A variety of bacteria have been isolated
from different stone samples confirming the dominance of Gram-positive organisms
especially spore-forming bacteria such as Bacillus and filamentous actinomycetes
(Ripka 2005)
In cultivation studies of deteriorated mural and rock paintings bacterial isolates
have frequently been attributed to the genus Bacillus (Weirich 1989 Tate and Rebrikova
1991 Gonzalez et al 1999 Heyrman et al 1999 Jimenez et al 2000) Other studies that
have included DNA-based techniques to characterize the bacterial community involved in
biodeterioration have shown that a substantial part of the bacterial population is made up of
so far unknown species (Altenburger et al 1996 Rolleke et al 1996 Gurtner et al 2000
Heyrman and Swings 2001) (Heymann et al 2003)
Many potential mycotoxin producers have been detected in air and items from
indoor environments with histories of exposure to moisture for example species of
Acremonium Alternaria Aspergillus Chateomium Fusarium Eurotium Paecilomyces
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
25 Review of Literature
Penicillium Scopulariopsis Stachybotrys Trichoderma Verticillium and Wallemia
(Peltola et al 2001 Pieckova et al 2001) Not all strains of one species produce
mycotoxins and different strains may produce different toxins Whereas toxin producing
strains are frequent in crops and outdoor vegetation toxin producing isolates from indoor
environments and non living assets have only been reported of the species Aspergillus
versicolor (Nielsen et al 1998) Stachybotrys chartarum Nikulin (1997) and
Trichoderma harzianum (Peltola et al 2001) Streptomyces griseus strains producing
valinomycin occur in environments where humans can get exposed
(Andersson et al 2002) The biological properties and toxicity mechanisms of cereulide
were identical to those by valinomycin (Mikkola et al 1999 Salonen et al 2001)
The genus Paenibacillus was first proposed by Ash et al (1993) and its description
was emended by Shida et al (1997) The genus Paenibacillus is under intensive taxonomic
investigation with ten species having been formally described in the last year Heyrman amp
Swings (2001) isolated a strain originally classified as Paenibacillus sp LMG 19508
from biodeteriorated mural paintings in the Servilia tomb at the Roman necropolis of
Carmona in Seville Spain (Smerda et al 2006) Building stone and wall paintings contain
a variety of hydroscopic salts including carbonates chlorides nitrates sulfates etc
dispersed within the porous material or locally concentrated These salts are solubilised
and migrate with the water in and out of the stone Due to changes in physical parameters
the so called salt efflorescences appear on the surfaces providing extremely saline
environments and building niches for settlement of halophilic microorganisms Halite and
other hygroscopic salts can retain considerable quantities of moisture when entrapped in
the building materials and thus favouring the bacterial growth (Ripka 2005)
It is demonstrated that water-damaged indoor building materials contained
substances of microbial origin extremely toxic to eukaryotic cells and large quantities of
several microbial species known to be potentially toxic or immunopotentiating These
include peptidoglycans Gram-negative endotoxin β-13-D glucans lipoglycans and
teichoic acids and mycotoxins (Jimenez 2000) In turn these microorganisms can mediate
the crystallization process These crystallizations can produce destructive effects Some
salts may crystallize or recrystallize to different hydrates which occupy a larger space and
exert additional pressure producing cracking powdering and flaking
(Jimenez and Laiz 2000)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
26 Review of Literature
211 Types of deterioration on mural paintings
The frescos represent a variety of ecological niches where primary colonization is
due to photoautotrophic and chemolithoautotrophic microorganisms followed by
secondary colonization due to heterotrophic bacteria that obtain nutrients from various
sources (metabolites of autotrophic bacteria airborne organic contamination animal faeces
and organic compounds in the paint layers themselves) Microbial-induced deterioration
processes cause structural as well as aesthetic damage to wall paintings such as the
discoloration of materials the formation of crusts on surfaces and the loss of material
(Sarro et al 2006 Osburn et al 2011) Halophilic bacteria and archaea were thought to
be found only in extreme environments like salt lakes or black smokers However it has
been shown that mural paintings and stones are a common habitat for extremely salt
tolerant and moderate halophilic (Ripka 2005) Microbial induced deterioration processes
can cause different kinds of alterations such as discolouration of materials the formation of
crusts on surfaces and the loss of material which leads to structural damage (Ripka 2005)
First of all microorganisms can cause severe problems due to the excretion of aggressive
metabolic products such as organic or inorganic acids Secondly material components can
be used as substrates for microbial metabolism Exoenzymes such as cellulases proteases
tannases beta-glucosidase produced by fungi and bacteria are responsible for hydrolysis of
cellulose and proteins Further examples are mechanical processes caused by swelling and
shrinking of slime or mycelia penetrating inside plaster of the painting resulting in loss of
cohesion and detachment of the paint layer (Rolleke 1996 Gurtner et al 2000)
Table-21 Microbial damage on mural paintings (Rolleke 1996)
S No Damage Microbial activity
1 Green brown red grey
surface layers (patinas)
Pigments produced by microorganisms (intra-or
extracellular) as chlorophyll and carotinoids
2 Dislodging of painting layers Use of organic binders as nutrient and energy
source
3 Acid attack of carbonates Acid produced by fungi or bacteria
4 Discolouration of pigments Redox-reactions induced by fungi and
bacteria
5 Loss of paint layer Growth of microorganisms deep into the plaster
6 Hydrolysis of synthetic
polymers Chemoorganotrophic activity of bacteria and fungi
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
27 Review of Literature
Discolorations are caused by excretion of pigments and microbiologically induced
reductionoxidation-processes (Krumbein et al 1990) Degradation of the bindings is
followed by reduction of stability Oxidation of ammonium and reduced sulphur
compounds results in acidification of the environment such as Sulphuric acid and the
variety of organic acids produced by the heterotrophs cause solubilization of calcareous
binding material and chelation of metal ions (Bock et al 1993) It is now well recognised
that wall paintings can be deteriorated by microorganisms (Ciferri 1999)The growth of
microorganisms essentially results in two types of damage aesthetic and structural
Aesthetic damage implies pigment discoloration stains and formation of a biofilm on the
painted surface Structural damage is observed as cracking and disintegration of the paint
layer formation of paint blisters and degradation of support polymers or of glues and
binders resulting in detachment of paint layer from the support The colonization of mural
paintings by bacteria and other microorganisms can have different causes Provided that
favorable environmental conditions occur nutrients for heterotrophic bacteria and fungi
can be available from metabolites of autotrophic bacteria from airborne contamination and
dripping water from animal faeces but also from organic compounds in the paint layer
itself
212 Methods of studying biodeterioration
It is now well recognized that wall paintings may be deteriorated by
microorganisms as established by several studies that linked the observed damage with the
microbial community present as reviewed by Ciferri (1999) Despite this knowledge a
reliable characterization of bacteria associated with such damage is often lacking To
obtain greater insight into the bacterial community involved in biodeterioration of mural
paintings three sites (from the necropolis at Carmona Spain and the Saint-Catherine
chapel of the castle at Herberstein Austria) were sampled In previous studies from these
sites 385 isolates were analysed by fatty acid methyl ester GC and representatives of
different fatty acid clusters were further studied by 16S rRNA gene sequencing
(Heyrman and Swings 2001) Several of these representative strains showed the highest
sequence similarity with members of the genus Arthrobacter (Heyrman et al 2005)
Jimenez and Samson (1981) analysed the microbial flora of a large fresco painted
in the late 1920s in the monastery ldquoSanta Maria de la Rabidardquo (Huelva Spain) exhibiting
two types of deterioration white efflorescence and green-to-black stains
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
28 Review of Literature
Tate and Rebrikova (1990) thought autotrophic nitrifying bacteria to be the first colonisers
of damaged frescoes and building materials in the cathedral of the nativity of the Virgin in
the Pafnutii-Borovskii monastery (Russia) The bulk of research on biodeterioration of
mural paintings has focused on explaining the observed phenomena by analysing the
microflora present Following this approach a precise characterisation of the
microorganisms using a polyphasic approach was never the first goal
Only a few studies included genomic fingerprinting (16S rDNA sequence analysis)
for the characterisation of bacteria associated with damage on mural paintings
[Rolleke (1996) Pinar et al (2001)] Previous studies based on culture-dependent
techniques showed that the flora present on frescos are fungi (predominant species of
Penicillium Aspergillus Cladosporium and Engyodontium) (Guglielminetti et al 1994)
bacteria (predominant species of Bacillus Arthrobacter Micrococcus Streptomyces and
Pseudomonas) (Heyrman et al 1999) cyanobacteria and eukaryotic algae (species of
Nostoc Lyngbya and Chlorophyceae) (Arino et al 1996 Calvo et al 1993) The killing
effect of an antimicrobial agent on a microorganism can be assessed in several ways
(1) Lethal activity may be expressed as the rate of killing by a fixed concentration
of drug under controlled conditions This rate is determined by measuring the number of
viable bacteria at various time intervals The resulting graphic depiction is known as the
time-kill curve Bacterial killing rates are in part dependent on the class of antibiotic and
the concentration of this agent With certain classes of antibiotics (eg aminoglycosides
and fluoroquino-lones) the rate of killing increases with increased drug concentrations up
to a point of maximum effect This is termed concentration-dependent bactericidal activity
In contrast the killing rates of szlig-lactam agents and vancomycin are relatively slow and
continue only as long as the concentrations are in excess of the MIC This rate of killing is
termed time-dependent bactericidal activity
(2) The minimal concentration of drug needed to kill most of the viable organisms
after incubation for a fixed length of time (generally 24 hours) under a given set of
conditions is the most common estimation of bactericidal activity and is known as either
the minimal bactericidal concentration (MBC) or the minimal lethal concentration (MLC)
It will be referred to in this document as the MBC Unfortunately the definition of the
MBC (999 killing of the final inoculum) is somewhat arbitrary and separates the
bacteria into two populations ndash a segrega-tion which might not have biological relevance
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
29 Review of Literature
The determination of the MBC moreover is so subject to methodologic variables that the
clinical relevance of MBCs is nearly impossible to assess particularly for certain pathogen
and drug combinations (eg Staphylococci and beta-lactam agents)
(3) The serum of a patient receiving an antibiotic may be tested against the
infecting microorganism This can be done using time-kill curve methodology (ie serum
bactericidal rate) or using dilution methodology (ie serum bactericidal titer) The
principles of these methods as well as the influence of biological and technical factors are
similar (Barry et al 1999)
213 Microbial flora associated with deteriorated mural paintings
A great deal of research has been done in this field mainly by using cultivation dependent
methods However by using culture-dependent methods only a very small proportion of
microorganisms can be obtained Far less than 1 of organisms in the environment can be
cultivated by standard cultivation techniques (Pace 1996) Recent studies have shown that
culture-dependent techniques yielded mainly sporeforming bacteria suggesting that plating
leads to an over estimation of the number of spore-forming bacteria A wide number of
investigations have shown that in addition to chemical and physical processes
microorganisms play a major role in degradation of objects of art such as paintings stone-
works wood paper masonry leather parchment glass and metal (Ripka 2005)
A) Bacteria
In general growth of diverse organisms on mural paintings is supported by
humidity slight alkaline pH values and the presence of organic and inorganic nutrient
sources (Weirich 1989) In mural paintings pigments are suspended in water or oil often
binders such as casein and milk are used and they are supplied on the damp lime plaster
(Ciferri 1999) The calcium carbonate formed on contact with air consolidates the
pigments Thus frescos contain mainly inorganic components While chemoautotrophic
nitrifiers and thiobacilli obtain their energy for growth by oxidizing ammonium and
reducing sulphur-compounds respectively heterotrophic bacteria and fungi depend on
organically bound carbon [Tate et al (1991) Lazar (1971) Petushkova et al (1986)
Jimenez et al (1981)] Thus primary colonization of photoautotrophic Cyanobacteria
chemolithoautotrophic nitrifying bacteria and sulphuric acid producing thiobacilli represent
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
30 Review of Literature
the first supply of organic matter The death and lysis of such bacteria promotes the
secondary settlement of heterotrophic bacteria and fungal populations (Calvo et al 1991)
Bacteria may derive from plants or pollen as many sequences obtained in this study
gave high score similarities with bacteria isolated from plants like Moraxella osloensis
Enterobacter cloace Enterobacter agglomerans and Pantoea endophytica Bacteria may
also derive from animal faeces like flies Bacillus Pseudomonas Aeromonas and Panteoa
(Ripka 2005) As Lazar and Dumitru (1973) reported studying mural paintings in a
Romanian monastery the genera Bacillus Arthrobacter and Pseudomonas have been
proved to produce salt efflorescences and were even considered to cause the blanching
phenomenon of frescoes (Jimenez et al 2000) Predominant bacterial genera are Bacillus
Streptomyces Arthrobacter Micrococcus and Pseudomonas [Weirich (1989)
Tate et al (1990) Arroyo et al (1997) Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
B) Fungi
It may be concluded that there is wide variety of fungal forms present on mural
paintings but Aspergillus and Alternaria were found dominating from all the experimental
sites next to them were Cladosporium Drechestera Fusarium Curvularia Chaetomium
Memnoniella Mycelia sterelai Pencillium Emericella Stachybotrytis Trichoderma
Phoma Monodictys Humicola and Epicoccum (Garg et al 1995)
The fungal genera most commonly found in lists of isolated taxa given in literature
are Alternaria Aspergillus Chaetomium Cladosporium Fusarium Penicillium and
Verticullum [Weirich (1989) Tate et al (1990) Guglielminetti et al (1994)
Garg et al (1995) Berner et al (1997) Ciferri (1999)] Some fungi having hard fruiting
bodies represented by sclerotia pycnidia perithecia cleistothecia and stroma could
organize themselves inside the painted layer Many fungal forms having such structures
were identified from our experimental sites viz Emericella nidulans A flavus
Chaetomium sp and Phoma sp etc These structures with little increase in humidity may
cause swelling in the paint film (Garg 1995)
Strains of species of Alternaria and Cladosporium both of them identified on the
mural paintings of the Palace of Schoumlnbrunn are the most common genera isolated from
stone and mural paintings in indoor environments with standard cultivation methods
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
31 Review of Literature
(Ventosa 2004) Saprophytic species of the genus Cladosporium are among the most
abundant fungi isolated in saltern samples Commonly isolated Cyanobacteria belong to
Nostoc and eukaryotic algae to Lyngbya and members of the Chlorophyceae such as
Chlorella Pseudococcomyxa and Pseudopleurococcus [Gorbushina et al (1987)
Calvo et al (1993) Arino et al (1996)]
They grow optimally on media with low water activity due to high salt or sugar
concentrations seem to propagate 70 vegetatively in the salterns and are thus
halotolerantosmotolerant species rather than simple flush-through occurrences
Cladiosporum herbarum was frequently isolated from hypersaline waters dead and dying
plant material air soil food fruit cereals paint and textiles (Ventosa 2004)
C) Algae
Most of the painted areas in temperature climate became covered with green algae
(Pleurococcus Protococcus and Trentopholia) while under tropical conditions blue green
algae of the genera Oscillatoria and Sytonema predominated (Garg 1995) The main
factors which contribute to the growth of algae on wall paintings are the presence of
moisture in the plaster as well as availability of visible light These conditions are quite
prevalent in the tropical climate but in temperature regions also algal growth on wall
paintings have been reported [Tonolo et al (1961) Pietrini et al (1991)]
D) Actinomycetes
Usually literature refers to specific aspects eg the occurrence of cyanobacteria
and algae in caves with natural openings to sunlight or those with artificial lighting fungi
and so forth Actinomycetes have been considered to be mainly confined to soils where
they find their natural habitat but despite intensive studies there are still many gaps in our
knowledge of the role played by actinomycetes in soil processes and biodegrations of
murals cave paintings (Groth et al 1999) In addition halophilic bacteria actinomycetes
and cyanobacteria are also capable of growing on salt-affected mural paintings
(Karbowska 2003)
Monte and Ferrari (1993) reviewed the mechanisms of biodeterioration in tombs
and underground churches The role of actinomycetes in the deterioration of frescoes in
hypogean environments was stressed by Agarossi et al (1985) Monte and Ferrari (1993)
Giacobini et al (1987) described the serious damage suffered by a whole series of famous
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
32 Review of Literature
frescoes in underground environments Actinomycetes were isolated from these mural
paintings located in crypts caves and tombs About 200 strains of actinomycetes were
isolated 60 of which were identified The most frequent species were Streptomyces albus
S cinereoruber S griseolus S vinaceus and some members of the Nocardia genus
Heterotrophic bacteria and actinomycetes were the most abundant microorganisms
on the frescoes of Etruscan tombs (Agarossi et al 1985) Bettini et al (1977) studied
some of the oldest Etruscan tombs (7th to 4th century BC) and found white-grey patinas
and spots from streptomycetes in the mural paintings They related the biodeterioration to
the microclimatic conditions (eg lower temperatures high RH) Monte and Ferrari (1993)
considered that colonization of the mural paintings was the result of selective competitive
and inhibitory dynamics among different microorganisms under different and changing
environmental conditions The pigments excreted by some actinomycetes were responsible
for the violet stains found on the walls of tombs in Tarquinia Similar stains were observed
in one of the Roman tombs the Circular Mausoleum the Necropolis of Carmona Spain
from which a Streptomyces sp producing violet pigments in culture media was isolated
214 Identification of biodeteriogens
The possibility of pigments and biodeteriogens identification in frescos and stone
monitoring is offered mostly by vibrational spectroscopy infrared thermography laser
induced fluorescence (LIF) laser induced breakdown spectroscopy (LIBS) XRF (X-Ray
Fluorescence) IR and UV emission Among them laser based methods allowing for in
situ or remote characterization of artwork surface were applied successfully for
prospecting diagnosis and maintenance (Colao et al 2005) The rep-PCR fingerprinting
of the isolates allowed determination of their genotypic diversity Studies that have
compared rep-PCR genomic fingerprint analysis with DNAndashDNA relatedness studies have
shown that the two techniques yield results that are in close agreement [Nick et al (1999)
Rademaker et al (2000)] These studies therefore suggest that rep-PCR fingerprinting can
be used as a genomic screening method to differentiate at the species level and to select
representatives for DNAndashDNA reassociation experiments (Heymann et al 2003)
The characterisation of bacteria was for example often limited to isolation from
group-specific media followed by microscopy [Sorlini et al (1987) Weirich (1989)
Tate et al (1990) and in more recent studies to morphological and physiological
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
33 Review of Literature
characteristics including miniaturised and automated systems such as API and BIOLOG
[Arroyo et al (1997) Jimmenez et al (2000) and Laiz et al (2000)] or to
chemotaxonomic characteristics [Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
Wagner et al (1994) demonstrated that conventional microbiological efforts can
fail to isolate all microorganisms present in natural samples DNA-based techniques used
to identify microorganisms have revealed only a smaller fraction of bacteria isolated from
artworks (Ward et al 1990 Rolleke et al 1996) Bacterial identification using molecular
techniques especially those including the sequencing of genes coding for ribosomal
16S rRNA is very important to study bacterial communities found on artefacts One such
method is Denaturing Gradient Gel Electrophoresis (DGGE) of PCR-amplified gene
fragments coding for rRNA (Muyzer et al 1993) that allows the separation of partial
16S rDNA amplified fragments of identical length but different sequence due to their
different melting behaviour in a gel system containing a gradient of denaturants
(Jimenez 2003)
Total genomic DNA was purified for 16S rRNA gene sequencing and rep-PCR
using a slight modification of the method of Pitcher et al (1989) as described by
Heyndrickx et al (1996) rep-PCR genomic fingerprinting was performed with the REP-
and (GTG)5 primers (Versalovic et al 1994) using the PCR conditions described
previously by Rademaker et al (1997) Electrophoresis and pattern analysis were further
performed as described by Heyrman et al (2003) 16S rRNA gene sequencing and
phylogenetic analysis were performed as described by Heyrman and Swings (2001)
Phylogenetic trees were constructed using the BioNumerics software (Applied Maths) by
applying the neighbour-joining and maximum-parsimony methods on a multiple alignment
similarity matrix The stability of relationships was assessed by a bootstrap analysis of
1000 datasets For determination of the G+C content and levels of DNAndashDNA
hybridization approximately 1 g biomass was harvested from agar plates DNA was
purified by using a combination of the protocols of Marmur (1961) and
Pitcher et al (1989) as described by Logan et al (2000) The G+C content of the DNA
was determined by HPLC (Mesbah et al 1989) using the further specifications given by
Logan et al (2000) DNAndashDNA hybridization experiments were performed using a
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
34 Review of Literature
modification of the microplate method of Ezaki et al (1989) as described by
Willems et al (2001)
215 Preservation and conservation
Nowadays the conservation and preservation of our cultural heritage is one of the
world main concerns particularly in Europe The increasing need for non-destructive
investigation tools has become a major issue as sampling is in most cases restricted in
view of the value or the uniqueness of the object Artworks as wall paintings in buildings
and monuments of historical interest are affected by environment physical (temperature
and humidity) and biological factors (biodeteriogens) and by human (pollutant releases)
impact and therefore modified over the time The term ldquoconservationrdquo may have many
different meanings in different fields Every intervention directed to the restoration and
safeguard of works of art is commonly considered as a conservation treatment For
example conservation can involve the cleaning procedures set up by chemists or the photo
documentation of the preservation of historical memory For the appropriate conservation
of works of art even the lighting systems in a museum or the control of the visitorrsquos
movements in a site should be monitored Chemical degradation which induces the flaking
of paintings and deterioration from rain wind dust and other environmental causes is
mainly responsible for the weakening of the porous structure and the surface layers of the
materials used in works of cultural heritage (Colao et al 2005)
216 Conservation history
Wall paintings are an integral part of monuments and sites and should be preserved
in situ Many of the problems affecting wall paintings are linked to the poor condition of
the building or structure its improper use lack of maintenance frequent repairs and
alterations Also frequent restorations unnecessary uncovering and use of inappropriate
methods and materials can result in irreparable damage Substandard and inadequate
practices and professional qualifications have led to unfortunate results It is for this reason
that an appropriate document covering the principles of proper conservation-restoration of
wall paintings is necessary
The Venice Charter (1964) has provided general principles for the conservation-
restoration of cultural heritage The Amsterdam Declaration (1975) introducing the
concept of integrated conservation and the Nara Document on Authenticity (1994) dealing
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
35 Review of Literature
with cultural diversity have expanded these principles Taking into account these and
additional relevant contributions such as the ICOM-CC Code of Ethics (1984) Document
of Pavia (1997) and ECCO Professional Guidelines (1997) the aim of this document is
to provide more specific principles for the protection preservation and the conservation
restoration of wall paintings This document therefore reflects basic and universally
applicable principles and practices and does not take into account particular problems of
regions or countries which can be supplemented at regional and national level by
providing further recommendations where necessary
217 Preservation techniques of the mural paintings
The removal of fat salts varnishes and pollutants from the surfaces of the works
of art are mostly done by chemical and mechanical methods At the end of the 19th
century the practices of restoration methods that do not inhibit further future interventions
was considered acceptable During the 1960s several chemicals such as polymeric resins
were synthesized and applied as a consolidation or protection agents The accepted idea
was that these substances could be removed at any time leaving a completely unaltered
substrate On the basis of origin archaeological objects can be classified as follows
(Carretti 2005)
1 Inorganic It includes siliceous and nonsiliceous materials Archaeological materials
produced from stones terracotta ceramics and glass can be included under siliceous
materials whereas objects made of metals can be included under nonsiliceous inorganic
materials Again metal objects can be classified as ferrous metals and non-ferrous metals
Objects made of iron are termed as ferrous metal objects whereas metal objects made from
other than iron is termed as non-ferrous metal objects
2 Organic It includes archival and anthropological materials Again archival materials
include paper bhojapatra tadapatra textiles wooden objects miniature paintings whereas
anthropological objects include bone and ivory leather feather and fur etc
In the past restoration of paintings and other old artwork often involved application
of acrylic resins to consolidate and protect them One of the most important tasks for
modern restorers is thus to remove these layers because it turns out that acrylic resins not
only by drastically changing the optics of the treated artwork but in many cases they
accelerate their degradation The scientists use an oil-in-water microemulsion with the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
36 Review of Literature
organic solvent para-xylene as the oil component The matrix makes the cleaning agent
viscous so that it cannot enter very far into the pores of a painting (Carretti 2005)
Nanoparticle treatment is the logical evolution of the Ferroni-Dini method
Dispersions of kinetically stable Ca (OH)2 nanoparticles in non-aqueous solvents solved
most of the drawbacks of the microsized powders Stable dispersions of calcium hydroxide
have been successfully applied (replacing polymers) as fixatives to re-adhere lifted paint
layers during many restoration workshops in Italy and in Europe as a consolidant The
FerronindashDini method (two steps the application of a saturated solution of ammonium
carbonate (NH4)2CO3 and the treatment with a barium hydroxide solution Ba(OH)2 also
called the barium method has long been the acknowledged method for the removal of
salts that threaten paintings reinforcing at the same time the porous structure However
commercially available carbonates and hydroxide powders have dimensions of several
micrometres much larger than the pores on the paint surface This means they donrsquot
penetrate the painting well and there is also a risk of damaging the artwork by a white
glaze forming on the surface (Berger 2006) Restoration should provide the reinforcement
of the porous structure and the consolidation of the surface layer of arte facts A few
simple principles can be considered to define the most appropriate restoration method
1) The treatment should be reversible so that one can revert to the original status of the
work of art at any desired time
2) All the applied chemicals must ensure the maximum durability and the chemical
inertness
3) The applied chemicals must invert the degradation processes without altering the
chemical composition of the artefacts and their physico-chemical and mechanical
properties (Baglioni 2006)
218 Commercial preservative used for preservation of mural paintings
Cleaning was done using soft brushes vacuum cleaner and Gumma paine (dough)
a natural latex sponge Areas near the window were very dirty with black soot and were
cleaned with micro fibrous cloths moistened with synperonic N (surfactant alkyl phenol
ethoxylate based on nonyl phenol) and neutralized with clean water In several places the
paint layers had separated from the substrate (exfoli-ation) In that cases loose paint flakes
were stuck back using Paraloid B72 (10 solution in ethanol) as sparingly as possible
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
37 Review of Literature
Paraloid was injected with syringe behind the exfoliated area twice pushed and held back
with Melinex (polyester film) until fixed on the third application (Bionda et al 2002)
In a period of significant growth of molds and intensive efforts to stop the mold
contamination some of the lines of certain paintings were obscured or faded Solutions of
ethanol formalin 91 and Thiabendazole (TBZ) were used but they were not very
effective Para-formaldehyde fumigation was adopted beginning in 1981 to establish an
emergency treatment sensitivity of microorganisms from studied samples was tested
against Desogen by adding 1-3 (v v) in serial dilutions The best concentration
3 (vv) was applied with a brush to prevent spreading of the spores In order to overcome
the problem of fungal attack suitable fungicides carbendizeme or kiroxy-I or 5 solute of
N formaldehyde can be used Shellac solution in spirit or 2 solution of polyvinaycletate
in toluene can be used as preservative and consolidantsTo control insect and fungal attack
fumigants like pyrethrum DDT or 5 solution of sodium penta chlorophenate in kerosene
oil 2 to 5 solution of PVA in toluene or 2 to 5 solution of paraloid B-72 in toluene or
acetone be used (Miura 2009) Microclimatic conditions constitute a critical factor in the
conservation of cave paintings The unstable microclimatic condition is one of the factors
that always affect the state of conservation of mural paintings In the environmental-
monument system knowledge of the functional environment and climatic conditions of the
surroundings are necessary for the identification of causes of decay (Singh 2011)
Furthermore the risk of formation of indoor bioaerosols in residential and public
buildings (offices schools museums etc) has attracted interest in the last years due to
socio-economic as well as sanitary reasons (Ripka 2005) Thus it is important in aspects of
health and maintenance of Cultural Heritage to analyse the complete microflora to further
develop biocides for harmful microorganisms and methods for restoration of damaged
objects of art The biocidal testing was carried out on one representative algal species of
the two classes of algae viz Chlorococcum sp (green) and Chroococcus sp (blue-green)
found to be common in all the samples Efficiency tests were carried out both in liquid as
well as solid media containing algal suspensions by adding a biocide solution of known
concentration and determining the growth of the microorganism after the incubation
period The biocides used for the past studies were
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
11 Review of Literature
Figure-23 Ajanta caves
Figure-24 Mural Painting of Ajanta caves
Ellora Caves Maharashtra belong to the highest achievements of mankind both
regarding the engineering skills and arts Some 2000 years ago Pitalkhora Caves
(Maharashtra) were among the largest temple complexes in India These 11 - 14 caves
were created in 250 BC - 4th century AD In 4th century AD temples were adorned with
beautiful murals especially fine paintings have been preserved on columns of Cave 3
Traces of murals are in Cave 6 as well Already the oldest group of caves here - Buddhist
caves from 630 - 700 AD - contain paintings of Buddhist panteon Remnants of paintings
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
12 Review of Literature
are seen in the most beautiful temple - Cave 16 Kailasanatha circa 760 - 860 AD Some
Jain temples - Cave 32 (Indra Sabha) Cave 33 - contain remnants of valuable murals from
800 - 1000 AD - this artwork marks the end of ancient period in the Indian art and
beginning of medieval art (Baskaran 1975)
Figure-25 Ellora caves
There are surviving mural paintings from the 17th century onwards in Rajasthan
The verdant Pahari hills saw the finest continuation of the tradition of murals in India The
18th and 19th century paintings on the walls of the Rang Mahal in Chamba are among the
best surviving examples of Pahari murals The 18th century paintings on the walls of the
Viranchinarayan Temple at Buguda are some of the finest surviving murals of that period
in India
Figure-26 Paintings on the walls of the Rang Mahal in Chamba
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
13 Review of Literature
The most important sites of rock paintings in North India are at Bimbetka Gwalior
Tikla Ayra Bhanpura Rampura Singhauli Bhojpur Adamgrh Delware and Mirzapur
In South India they are found at Mehaboob Nagar (Andhrapradesh) Edakkal Marayoor
Perimkadavila (Kerala) Mallampadi (Tamilnadu) and Bellary (Karnataka)These
paintings were considered as the early models of mural paintingsThe mural painting of
Sittannavasal Badami Lepakshi Tanjore Vijayanagar and Kerala has a lot of similarities
(Sasibhoosan 1987)
25 South Indian murals
South India also got rich tradition of mural paintings In the reign of Cholas
Vijayanagaras and Nayakas this art reached the climax The Deccan art of Bijapur
Hyderabad and Golconda schools were influenced by the Mughal traditions and later by
European idiom Maratha murals are also shaped under the Mughal traditions and
employed oil as medium The Mural art of Kerala vividly depicted on the walls of temples
and monuments show the traces of European affinity In Tamil Nadu almost all the extent
examples of frescos have been done on rock surfaces and stone walls This is a crucial
factor in determining the quality of frescos (Havell 1982) The ceiling of the Virupaksha
temple in Hampi is covered with paintings of the 15th century The paintings on the ceiling
of the mandapa of Lepakshi temple are some of the finest mural paintings of the medieval
period in India Legends associated with Siva and Parvati Krishna and Rama were painted
on the walls of palaces and temples in Kerala from the 16th to 19th century Mural
paintings were made on the walls of all the palaces within the magnificent Orccha fort The
Raj Mahal was completely adorned with mural paintings of the 17th century
Figure-27 Virupaksha temple in Hampi
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
14 Review of Literature
Figure-28 Ceilings of Virupaksha temple Hampi
The murals on the walls of the navaranga (the central pillared hall) depict stories
from Bhagavatha and are excellent examples of 19th
century Mysore paintings The
Mallikarjunaswamy temple on the hill is one of the Panchalingas of Talakad and the
temple has a beautiful mural painting on the wall of the temple The Dariya Daulat Bagh
has excellent mural painting (Sasibhoosan 1987)
Figure-29 Paintings on the walls of Jagan mohan palace Mysore
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
15 Review of Literature
Figure-210 Painting of Raja woodeyar era
Kerala mural paintings are the frescos depicting mythology and legends which are
drawn on the walls of temples and churches in South India principally in Kerala Ancient
temples churches and palaces in Kerala South India display an abounding tradition of
mural paintings mostly dating back between the 9th to 12th centuries The murals of
Thirunadhikkara Cave Temple (now ceded to Tamilnadu) and Tiruvanchikulam are
considered the oldest relics of Keralarsquos own style of murals Fine mural paintings are
depicted in temples at Trikodithanam Ettumanur Vaikom Pundarikapuram
Udayanapuram Triprangode Guruvayoor Kumaranalloor Aymanam the Vadakkunathan
temple in Trichur and the Sri Padmanabhaswamy temple at Thiruvananthapuram Other
mural sites are in the churches at Edappally Vechur Cheppad and Mulanthuruthy and at
palaces such as the Krishnapuram Palace near Kayamkulam and the Padmanabhapuram
Palace
Figure-211 Kerala murals
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
16 Review of Literature
Figure-212 Murals paintings of Kerala temples
There are wall paintings in Badami in the Bijapur district Karnataka Some
excellent paintings exist in the Jain caves at Sitanavassal in Puddukkottai District of Tamil
Nadu Tamil Nadu gave exuberant and glorious expression to themes relating to Siva in the
temples of Panamalai and Kailashanatar in Kancheepuram In the 9th century Jain cave of
Sittannavasal in Tamil Nadu there is a marvellous lotus pond painted on the ceiling In
the heart of the Brihadeeswara temple in Thanjavur Tamil Nadu protected by massive
walls of stone are the finest paintings of the theme of Siva ever painted towards the end of
the 10th century (Sivaramamurthi 1992)
Figure-213 Kancheepuram Mural paintings
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
17 Review of Literature
Figure-214 Sculpture of Mahabalipuram
26 Methods of mural painting
In the history of mural several methods have been used The Buon fresco technique
consists of painting in pigment mixed with water on a thin layer of wet fresh lime mortar
or plaster The pigment is then absorbed by the wet plaster after a number of hours the
plaster dries and reacts with the air it is this chemical reaction which fixes the pigment
particles in the plaster After this the painting stays for a long time up to centuries in fresh
and brilliant colors A Secco painting is done on dry plaster The pigments thus require a
binding medium such as egg (tempera) glue or oil to attach the pigment to the wall
Mezzo-fresco is painted on nearly-dry plaster which is defined by the sixteenth-century
author Ignazio Pozzo as ldquofirm enough not to take a thumb-printrdquo so that the pigment only
penetrates slightly into the plaster Ancestral Hopi village archaeologists found that
fourteen kivas had painted murals and multiple layers of murals on the walls some with up
to twenty-seven layers of murals (Saturno 2006)
The colors used in painting are generally obtained from plants and minerals
Among them only such colors which are lime resistant are suitable for mural painting The
selection of proper colors for a mural painting is an important part of the work as the
longevity the painting depends on it Only mineral colors are preserved for a long time
which could be the reason for use of those colors in early days As per ldquoShilpa ratnardquo and
ldquoAgnipuranardquo the colors used in mural painting are white black red yellow blue and
green Yellow and red are from yellow ochre and red ochre Blue is generally indigo or
china blue White is the prepared wall and black is the carbon soot Mural paintings have
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
18 Review of Literature
survived centuries only on account of the identification and use of those colors which does
not have any reaction with lime (Miraseth 2006)
Originally three types of brushes were made and used flat medium and fine Flat
brushes were made from hairs behind calfrsquos ear the medium from the bottom of goats
belly and the fine brush from delicate blades of grass However in due course of time and
change use of easily available brushes from commercial market and shading of the
original colours can be distinctively noticed The use of blue colour is also noticed over the
passage of time The paintings have been brought down from the walls to plywood cloth
paper and other frames for easy to make and use purposes (Chakarabarti 1980)
27 Themes of mural painting
The subjects and themes in the murals are centered on the Hindu pantheon of Gods
and Goddesses drawn from description in the invocatory verses or Dhyana Slokas More
common representations are of Vishnu in different incarnations Ganesha and
manifestations of Siva We see murals in the Pallimanna Siva Temple devoted to Siva-
Parvatirsquos marriage the Ramayana Story being narrated on the walls of the Mattancheri
palace in the Sankara Narayana the Mahabharata is retold Murals are various scenes from
the Hindu epics and also the frolics of Lord Krishna
It would be interesting to bring into account the influence of the mural paintings on
Christianity On various churches like the St Georgersquos Orthodox Church has Christian
murals bringing out biblical characters and narrating stories from the scriptures Mar
Sabore and Afroth Church at Akapparambu in the outskirts of Ernakulam also have murals
of scenes from the bible Interestingly StMaryrsquos Church at Kanjoor has on both sides of its
entrance a battle scene between the armies of Tipu Sultan and of the English East India
Company It is also apparent that the history of Kerala Murals has its origin in the temple
walls and thus a study of Kerala Murals is not complete without pondering on the
architecture of Kerala its association with the murals (Warrier 2011)
28 Technique used in mural paintings
Indian murals executed on walls of caves structural temples walls of palaces were
based on highly developed techniques Mural painting is a composite structure of these
three basic layers the support the ground and the pigment layer In case of wall painting
the wall itself is the support This is followed by the layer or layers of plaster which
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
19 Review of Literature
constitute the ground The pigment layer is the one which contains the picture The support
is the wall which may be rock surface in a cave or a structural one These stone surfaces
which serve as carriers are rough or uneven This unevenness is itself an advantage as it
provides ldquotoothrdquo to hold the plaster on the surface The uneven surface of the wall has to be
made uniform with layers of plaster in successive gradation of fineness There is generally
one layer of rough plaster followed by one or more layers of fine plaster Ground or plaster
is a term used to mean the surface material of a wall or building which is applied as a
plastic mass made by mixing certain materials with water letting the mass set by drying
carbonation or hydration The active or setting components of plaster are commonly clay
which sets by drying lime which sets by carbonation gypsum and pozzolana which sets by
hydration (Mini 2010)
There are different mixtures for rough plaster In all the mixtures clay limestone
lime and shells in powdered form serve as the matrix The particles of which are held
together by the organic materials like gum glue extracts from barks etc are in fact
adhesives The fine plaster layer requires more careful preparation because it is the layer on
which the pigments are laid to make the picture ldquoShilparatnardquo suggest a mixture of conch
Oyster shells or white clay with gum of neem or slaked lime and coconut water Here the
consolidation is effected by the carbonation of slaked lime ie it absorbs carbon dioxide
from air and becomes carbonate Mural paintings were lime-washed from the 17th until the
beginning of 19th century A few paintings in vaults were never lime-washed for example
at Taby and Floda painted by the medieval painter Albertus Pictor (Mini 2010)
All the paintings have certain basic common characteristics There has to be a wall
or rock surface called support over which the artist goes to work A plaster base called
ground of varied thickness is laid on the support The ground may consist of one or more
layers The strength and life of the whole mural depended up on this ground over which the
painting was done It is the process of applying the final painting on the ground determines
the character of the mural whether it is fresco or tempera The mural painting is done
usually by creating wall surface free of any previous oil or paint by using solvent or by
sand blasting The brick wall is first plastered with mixture of lime and sand in the ratio of
12 A mixture of egg yolk vinegar oil colour is used in dry plaster
There are at least six stages before a Kerala Mural Painting is complete Lekhya
Karma is the first stage where sketching by pencil or crayon is done The second stage is
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
20 Review of Literature
the Rekha Karma which enhances the outlines of the sketching done The third stage called
Varna Karma breathes life into the painting with its colours Here all colours are
appropriately filled in The colouring of the human figures is done according to the
characters and their common virtues The divine and noble characters (Saatvik) are painted
in green those inclined towards power and wealth (Raajasik) is painted in shades of red
lowly mean characters (Tamasik) in white and demons in black In the fourth stage or the
Vartana Karma shading is done Fifth stage called the Lekha Karma brings us to the final
outline of the painting which is usually in black The final and the finishing touches stage
are called Devika Karma (Warrier 2011)
29 Dyes used in mural painting
Indians have been considered as fore runners in the art of natural dyeing Natural
dyes find use in the colouring of textiles drugs cosmetics etc Owing to their non-toxic
effects they are also used for colouring various food products In India there are more
than 450 plants that can yield dyes In addition to their dye-yielding characteristics some
of these plants also possess medicinal value Though there is a large plant resource base
little has been exploited so far Due to lack of availability of precise technical knowledge
on the extracting and dyeing technique it has not commercially succeeded like the
synthetic dyes (Siva 2007)
The color materials on the mural paintings in ancient India were derived from the
natural materials like terracotta chalk red ochre and yellow ochre mixed with animal fat
The dyes for painting is prepared such as white from lime Black from carbon soot of
lamps Red and yellow from minerals Blue from indigo ferra Deep red from lac A fine
coating of resin is done after the painting in order to make a shining appearance Egg yolk
and vinegar was mixed with oil colors and painted on dry plaster (Krishnakumar 1999)
Although plants exhibit a wide range of colours not all of these pigments can be
used as dyes Some do not dissolve in water some cannot be adsorbed onto fibres whereas
others fade when washed or exposed to air or sunlight It remains a mystery why plants
reward us with vibrant dyes India has a rich biodiversity and it is not only one of the
worldrsquos twelve mega diversity countries but also one of the eight major centres of origin
and diversification of domesticated taxa It has approximately 490000 plant species of
which about 17500 are angiosperms more than 400 are domesticated crop species and
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
21 Review of Literature
almost an equal number their wild relatives Thus India harbours a wealth of useful
germplasm resources and there is no doubt that the plant kingdom is a treasure-house of
diverse natural products One such product from nature is the dye (Siva 2007)
Many natural dyestuff and stains were obtained mainly from plants and dominated
as sources of natural dyes producing different colours like red yellow blue black brown
and a combination of these Almost all parts of the plants like root bark leaf fruit wood
seed flower etc produce dyes It is interesting to note that over 2000 pigments are
synthesized by various parts of plants of which only about 150 have been commercially
exploited Nearly 450 taxa are known to yield dyes in India alone of which 50 are
considered to be the most important ten of these are from roots four from barks five from
leaves seven from flowers seven from fruits three from seeds eight from wood and three
from gums and resins Some important dye-yielding plant habitats their distribution and
colouring pigment (Siva 2007)
The dye is generally prepared by boiling the crushed powder with water but
sometimes it is left to steep in cold water The solution then obtained is used generally to
dye coarse cotton fabrics Alum is generally used as a mordant Flowers of Butea
monosperma (Lam) Taubert yield an orange-coloured dye which is not fast and is easily
washed away For the purpose of colouring the material is steeped in a hot or cold
decoction of the flowers A more permanent colour is produced either by first preparing the
cloth with alum and wood ash or by adding these substances to the dye-bath The dye
indigo is produced by steeping the plant in water and allowing it to ferment This is
followed by oxidation of the solution with air in a separate vessel Mallotus philippinensis
muell yields an orange colour used for dyeing silk and wool To prepare the annatto dye
from B orellena the fruits are collected when nearly ripe The seeds and pulp are removed
from the mature fruit and macerated with water Thereafter they are either ground up into
an lsquoannatto pastersquo or dried and marketed as annatto seeds Sometimes when the seeds and
pulp are macerated with water the product is stained through a sieve and the colouring
matter which settles out is collected and partially evaporated by heat and finally dried in
the sun (Sowbhagya 2002)
The predominant colors used in rock art and cave art are black (from charcoal soot
or manganese oxide) yellow ochre (limonite) red ochre (hematite or baked limonite) and
white (kaolin clay burnt shells powdered gypsum or powdered calcium carbonate) All of
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
22 Review of Literature
theses pigments may be used on leather or raw hide as well Early cave art in Seminole
Canyon was monochromatic in red and as culture grew more sophisticated the color
palette expanded Blue Orange Brown Green and Purple are the most common colours
used in Ajantha murals White Pink Gold are occasionally represented mineral earths
containing ferric oxide and copper carbonates were used as source of red yellow and green
colours There is also evidence to establish that root of Rubia cardifolia and leaves of
Indigofera tinctoria were used as source for red and blue colours (Nayer et al 1999)
Many colors of pigments were obtained from both organic and inorganic sources in
ancient times and used to paint various surfaces such as braintan leather clothing and
accoutrements rawhide the human body etc Blue color was obtained from powdered
azurite and lapis duck manure and certain clays Fine Blue-green clay was obtained from
deposits near Mankato Michigan Organic sources of blue include Turkeys Tail a
greenish blue polypore that grows on dead decaying wood (not tannish ones) Native
Americans get Indigo from either Guatemala or Ecuador which was traded well up onto
Kansas long before the Spanish ever set foot here American Indigo has purple tones to it
but IndianJapanese indigo has green tones Berries and crushed flowers were also used to
obtain blue color by rubbing the plant material directly on the leather
An organic source of red was Cochineal It was native west of the Mississippi and
is produced from the bodies of small insects that grow on the prickly pear cactus Ladys
Bedstraw gives a good vermillion red color Harvest the roots dry them out clean the mud
etc off of them and then grind the roots really fine then soak them to extract the red
coloring The key here is drying the root first Blood was also used as red pigment Pucoon
roots also yield a red pigment (Smith 2002) Red ochre the reverse original red colours are
due to variations in iron oxide (or) calcite content and to redox conditions in the firing
produced Brown coloured ceramics owe their colour to maghemite and must be
considered as a fabrication defect due to the position of the ceramic piece in a zone where a
reducing atmosphere prevailed in the course of firingRed pigments were produced from
iron oxides like hematite or limonite and from ochre Hematite was the most frequently
used mineral It occurs in the form of aggregates of small red crystals or in the form of
bigger black crystals which are difficult to crush white was obtained mostly from
kaolinite or illite (Clottes et al 1990)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
23 Review of Literature
210 Biodetoriation of mural paintings
Historic items often contain natural biodegradable materials and have histories of
exposure to moist conditions These two conditions make them amenable to microbial
attack Microbial colonization may damage the building or the cultural asset
(Salonen 2001) Biodeteriogens are organisms involved in deterioration of artifacts They
are very specific for each type of artifact in accordance with its chemical structure and
environment They also have different nutritional requirements and act directly or
indirectly on the substrate The adhesion of microorganisms to a substrate is the result of
cell hydrophobicity and of excreted polymeric substances contained by sheaths capsules
and slimes (Colao 2005)
The surviving wall paintings and decorations in subterranean environments around
Malta are rather scarce (Buhagiar 1986 1993 1998) These include those at St Paulrsquos
Catacombs (Zammit 2008) St Agatharsquos Crypt and Catacombs (Camilleri 2001)
San Catald Catacombs Tac-Cghaqi Abbatija tad-Dejr (Buhagiar 1993) all in Rabat the
cave-sanctuary in Mellieħa (Buhagiar 1987) and the Ħal Saflieni Hypogeum in Paola
(Pace 2000) Previous studies conducted on wall paintings and decorations in Maltese
Palaeo-Christian Catacombs have involved their manufacturing techniques (Muscat 2005)
However to date limited systematic studies have been conducted into the biodeterioration
in Maltese Palaeo- Christian Catacombs The only such studies ever conducted in Malta
concerned the biodeterioration of works of art in catacombs have been carried out at St
Agatharsquos Crypt and Catacombs in Rabat (Zammit et al 2008 Psaila 2006)
Microorganisms can be responsible for the destruction of monuments buildings
and cultural heritage assets including the decay of concrete cement stones mural
paintings etc These microorganisms are not only related with biodeterioration but water-
damaged indoor building materials are frequently colonized by complex bacterial
communities and may emit mixed bioaerosols into the indoor air (Jimenez 2000) It is
well known that mural paintings are colonized by micro-organisms and can be severely
damaged by such growths (Ciferri 1999) A large number of fungal (gt50) and bacterial
taxa (70) have been detected in indoor environments Over 50 bacterial species and 14
genera novel to science were reported in the past 10 years from indoor air and historic
items indicating bacterigravea in these enviroments are as yet only fragmentarily known
(Salonen 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
24 Review of Literature
Traditionally the study of microflora which causes this biodeterioration was based
on classical cultivation methods that were mainly useful to study the physiological
potential of microorganisms but do not provide information on all microbial communities
to be found in excavated artifacts Indeed many studies using culture-independent
techniques which cultivate microorganisms from different environments may often
represent only minor components of the microbial community as a whole It is generally
accepted that cultivation methods recover less than 1 of the total microorganisms present
in environmental samples (Ward et al 1990 Amann et al 1995) Hence microbial
investigations based only on cultivation strategies cannot be regarded as reliable in terms
of reflecting the microbial diversity present in objects of art (Osburn et al 2011)
Early workers suggested that the presence of living microorganisms on stone
increased its susceptibility to damage through their water-binding capacity It has recently
been reported that the mineralogy porosity surface roughness and capacity to collect
water and organic materials control its bioreceptivity and tendency to biodeterioration
(Diakumaku 1995) In addition environmental factors as temperature light pH and
relative humidity affect the number and type of colonising species (Tiano et al 1995) and
hence the progress of colonisation Biofilms on decayed stones consist on mixed microbial
populations embedded in a polymeric matrix Fungi algae filamentous and unicellular
bacteria are found in these complex communities A variety of bacteria have been isolated
from different stone samples confirming the dominance of Gram-positive organisms
especially spore-forming bacteria such as Bacillus and filamentous actinomycetes
(Ripka 2005)
In cultivation studies of deteriorated mural and rock paintings bacterial isolates
have frequently been attributed to the genus Bacillus (Weirich 1989 Tate and Rebrikova
1991 Gonzalez et al 1999 Heyrman et al 1999 Jimenez et al 2000) Other studies that
have included DNA-based techniques to characterize the bacterial community involved in
biodeterioration have shown that a substantial part of the bacterial population is made up of
so far unknown species (Altenburger et al 1996 Rolleke et al 1996 Gurtner et al 2000
Heyrman and Swings 2001) (Heymann et al 2003)
Many potential mycotoxin producers have been detected in air and items from
indoor environments with histories of exposure to moisture for example species of
Acremonium Alternaria Aspergillus Chateomium Fusarium Eurotium Paecilomyces
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
25 Review of Literature
Penicillium Scopulariopsis Stachybotrys Trichoderma Verticillium and Wallemia
(Peltola et al 2001 Pieckova et al 2001) Not all strains of one species produce
mycotoxins and different strains may produce different toxins Whereas toxin producing
strains are frequent in crops and outdoor vegetation toxin producing isolates from indoor
environments and non living assets have only been reported of the species Aspergillus
versicolor (Nielsen et al 1998) Stachybotrys chartarum Nikulin (1997) and
Trichoderma harzianum (Peltola et al 2001) Streptomyces griseus strains producing
valinomycin occur in environments where humans can get exposed
(Andersson et al 2002) The biological properties and toxicity mechanisms of cereulide
were identical to those by valinomycin (Mikkola et al 1999 Salonen et al 2001)
The genus Paenibacillus was first proposed by Ash et al (1993) and its description
was emended by Shida et al (1997) The genus Paenibacillus is under intensive taxonomic
investigation with ten species having been formally described in the last year Heyrman amp
Swings (2001) isolated a strain originally classified as Paenibacillus sp LMG 19508
from biodeteriorated mural paintings in the Servilia tomb at the Roman necropolis of
Carmona in Seville Spain (Smerda et al 2006) Building stone and wall paintings contain
a variety of hydroscopic salts including carbonates chlorides nitrates sulfates etc
dispersed within the porous material or locally concentrated These salts are solubilised
and migrate with the water in and out of the stone Due to changes in physical parameters
the so called salt efflorescences appear on the surfaces providing extremely saline
environments and building niches for settlement of halophilic microorganisms Halite and
other hygroscopic salts can retain considerable quantities of moisture when entrapped in
the building materials and thus favouring the bacterial growth (Ripka 2005)
It is demonstrated that water-damaged indoor building materials contained
substances of microbial origin extremely toxic to eukaryotic cells and large quantities of
several microbial species known to be potentially toxic or immunopotentiating These
include peptidoglycans Gram-negative endotoxin β-13-D glucans lipoglycans and
teichoic acids and mycotoxins (Jimenez 2000) In turn these microorganisms can mediate
the crystallization process These crystallizations can produce destructive effects Some
salts may crystallize or recrystallize to different hydrates which occupy a larger space and
exert additional pressure producing cracking powdering and flaking
(Jimenez and Laiz 2000)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
26 Review of Literature
211 Types of deterioration on mural paintings
The frescos represent a variety of ecological niches where primary colonization is
due to photoautotrophic and chemolithoautotrophic microorganisms followed by
secondary colonization due to heterotrophic bacteria that obtain nutrients from various
sources (metabolites of autotrophic bacteria airborne organic contamination animal faeces
and organic compounds in the paint layers themselves) Microbial-induced deterioration
processes cause structural as well as aesthetic damage to wall paintings such as the
discoloration of materials the formation of crusts on surfaces and the loss of material
(Sarro et al 2006 Osburn et al 2011) Halophilic bacteria and archaea were thought to
be found only in extreme environments like salt lakes or black smokers However it has
been shown that mural paintings and stones are a common habitat for extremely salt
tolerant and moderate halophilic (Ripka 2005) Microbial induced deterioration processes
can cause different kinds of alterations such as discolouration of materials the formation of
crusts on surfaces and the loss of material which leads to structural damage (Ripka 2005)
First of all microorganisms can cause severe problems due to the excretion of aggressive
metabolic products such as organic or inorganic acids Secondly material components can
be used as substrates for microbial metabolism Exoenzymes such as cellulases proteases
tannases beta-glucosidase produced by fungi and bacteria are responsible for hydrolysis of
cellulose and proteins Further examples are mechanical processes caused by swelling and
shrinking of slime or mycelia penetrating inside plaster of the painting resulting in loss of
cohesion and detachment of the paint layer (Rolleke 1996 Gurtner et al 2000)
Table-21 Microbial damage on mural paintings (Rolleke 1996)
S No Damage Microbial activity
1 Green brown red grey
surface layers (patinas)
Pigments produced by microorganisms (intra-or
extracellular) as chlorophyll and carotinoids
2 Dislodging of painting layers Use of organic binders as nutrient and energy
source
3 Acid attack of carbonates Acid produced by fungi or bacteria
4 Discolouration of pigments Redox-reactions induced by fungi and
bacteria
5 Loss of paint layer Growth of microorganisms deep into the plaster
6 Hydrolysis of synthetic
polymers Chemoorganotrophic activity of bacteria and fungi
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
27 Review of Literature
Discolorations are caused by excretion of pigments and microbiologically induced
reductionoxidation-processes (Krumbein et al 1990) Degradation of the bindings is
followed by reduction of stability Oxidation of ammonium and reduced sulphur
compounds results in acidification of the environment such as Sulphuric acid and the
variety of organic acids produced by the heterotrophs cause solubilization of calcareous
binding material and chelation of metal ions (Bock et al 1993) It is now well recognised
that wall paintings can be deteriorated by microorganisms (Ciferri 1999)The growth of
microorganisms essentially results in two types of damage aesthetic and structural
Aesthetic damage implies pigment discoloration stains and formation of a biofilm on the
painted surface Structural damage is observed as cracking and disintegration of the paint
layer formation of paint blisters and degradation of support polymers or of glues and
binders resulting in detachment of paint layer from the support The colonization of mural
paintings by bacteria and other microorganisms can have different causes Provided that
favorable environmental conditions occur nutrients for heterotrophic bacteria and fungi
can be available from metabolites of autotrophic bacteria from airborne contamination and
dripping water from animal faeces but also from organic compounds in the paint layer
itself
212 Methods of studying biodeterioration
It is now well recognized that wall paintings may be deteriorated by
microorganisms as established by several studies that linked the observed damage with the
microbial community present as reviewed by Ciferri (1999) Despite this knowledge a
reliable characterization of bacteria associated with such damage is often lacking To
obtain greater insight into the bacterial community involved in biodeterioration of mural
paintings three sites (from the necropolis at Carmona Spain and the Saint-Catherine
chapel of the castle at Herberstein Austria) were sampled In previous studies from these
sites 385 isolates were analysed by fatty acid methyl ester GC and representatives of
different fatty acid clusters were further studied by 16S rRNA gene sequencing
(Heyrman and Swings 2001) Several of these representative strains showed the highest
sequence similarity with members of the genus Arthrobacter (Heyrman et al 2005)
Jimenez and Samson (1981) analysed the microbial flora of a large fresco painted
in the late 1920s in the monastery ldquoSanta Maria de la Rabidardquo (Huelva Spain) exhibiting
two types of deterioration white efflorescence and green-to-black stains
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
28 Review of Literature
Tate and Rebrikova (1990) thought autotrophic nitrifying bacteria to be the first colonisers
of damaged frescoes and building materials in the cathedral of the nativity of the Virgin in
the Pafnutii-Borovskii monastery (Russia) The bulk of research on biodeterioration of
mural paintings has focused on explaining the observed phenomena by analysing the
microflora present Following this approach a precise characterisation of the
microorganisms using a polyphasic approach was never the first goal
Only a few studies included genomic fingerprinting (16S rDNA sequence analysis)
for the characterisation of bacteria associated with damage on mural paintings
[Rolleke (1996) Pinar et al (2001)] Previous studies based on culture-dependent
techniques showed that the flora present on frescos are fungi (predominant species of
Penicillium Aspergillus Cladosporium and Engyodontium) (Guglielminetti et al 1994)
bacteria (predominant species of Bacillus Arthrobacter Micrococcus Streptomyces and
Pseudomonas) (Heyrman et al 1999) cyanobacteria and eukaryotic algae (species of
Nostoc Lyngbya and Chlorophyceae) (Arino et al 1996 Calvo et al 1993) The killing
effect of an antimicrobial agent on a microorganism can be assessed in several ways
(1) Lethal activity may be expressed as the rate of killing by a fixed concentration
of drug under controlled conditions This rate is determined by measuring the number of
viable bacteria at various time intervals The resulting graphic depiction is known as the
time-kill curve Bacterial killing rates are in part dependent on the class of antibiotic and
the concentration of this agent With certain classes of antibiotics (eg aminoglycosides
and fluoroquino-lones) the rate of killing increases with increased drug concentrations up
to a point of maximum effect This is termed concentration-dependent bactericidal activity
In contrast the killing rates of szlig-lactam agents and vancomycin are relatively slow and
continue only as long as the concentrations are in excess of the MIC This rate of killing is
termed time-dependent bactericidal activity
(2) The minimal concentration of drug needed to kill most of the viable organisms
after incubation for a fixed length of time (generally 24 hours) under a given set of
conditions is the most common estimation of bactericidal activity and is known as either
the minimal bactericidal concentration (MBC) or the minimal lethal concentration (MLC)
It will be referred to in this document as the MBC Unfortunately the definition of the
MBC (999 killing of the final inoculum) is somewhat arbitrary and separates the
bacteria into two populations ndash a segrega-tion which might not have biological relevance
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
29 Review of Literature
The determination of the MBC moreover is so subject to methodologic variables that the
clinical relevance of MBCs is nearly impossible to assess particularly for certain pathogen
and drug combinations (eg Staphylococci and beta-lactam agents)
(3) The serum of a patient receiving an antibiotic may be tested against the
infecting microorganism This can be done using time-kill curve methodology (ie serum
bactericidal rate) or using dilution methodology (ie serum bactericidal titer) The
principles of these methods as well as the influence of biological and technical factors are
similar (Barry et al 1999)
213 Microbial flora associated with deteriorated mural paintings
A great deal of research has been done in this field mainly by using cultivation dependent
methods However by using culture-dependent methods only a very small proportion of
microorganisms can be obtained Far less than 1 of organisms in the environment can be
cultivated by standard cultivation techniques (Pace 1996) Recent studies have shown that
culture-dependent techniques yielded mainly sporeforming bacteria suggesting that plating
leads to an over estimation of the number of spore-forming bacteria A wide number of
investigations have shown that in addition to chemical and physical processes
microorganisms play a major role in degradation of objects of art such as paintings stone-
works wood paper masonry leather parchment glass and metal (Ripka 2005)
A) Bacteria
In general growth of diverse organisms on mural paintings is supported by
humidity slight alkaline pH values and the presence of organic and inorganic nutrient
sources (Weirich 1989) In mural paintings pigments are suspended in water or oil often
binders such as casein and milk are used and they are supplied on the damp lime plaster
(Ciferri 1999) The calcium carbonate formed on contact with air consolidates the
pigments Thus frescos contain mainly inorganic components While chemoautotrophic
nitrifiers and thiobacilli obtain their energy for growth by oxidizing ammonium and
reducing sulphur-compounds respectively heterotrophic bacteria and fungi depend on
organically bound carbon [Tate et al (1991) Lazar (1971) Petushkova et al (1986)
Jimenez et al (1981)] Thus primary colonization of photoautotrophic Cyanobacteria
chemolithoautotrophic nitrifying bacteria and sulphuric acid producing thiobacilli represent
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
30 Review of Literature
the first supply of organic matter The death and lysis of such bacteria promotes the
secondary settlement of heterotrophic bacteria and fungal populations (Calvo et al 1991)
Bacteria may derive from plants or pollen as many sequences obtained in this study
gave high score similarities with bacteria isolated from plants like Moraxella osloensis
Enterobacter cloace Enterobacter agglomerans and Pantoea endophytica Bacteria may
also derive from animal faeces like flies Bacillus Pseudomonas Aeromonas and Panteoa
(Ripka 2005) As Lazar and Dumitru (1973) reported studying mural paintings in a
Romanian monastery the genera Bacillus Arthrobacter and Pseudomonas have been
proved to produce salt efflorescences and were even considered to cause the blanching
phenomenon of frescoes (Jimenez et al 2000) Predominant bacterial genera are Bacillus
Streptomyces Arthrobacter Micrococcus and Pseudomonas [Weirich (1989)
Tate et al (1990) Arroyo et al (1997) Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
B) Fungi
It may be concluded that there is wide variety of fungal forms present on mural
paintings but Aspergillus and Alternaria were found dominating from all the experimental
sites next to them were Cladosporium Drechestera Fusarium Curvularia Chaetomium
Memnoniella Mycelia sterelai Pencillium Emericella Stachybotrytis Trichoderma
Phoma Monodictys Humicola and Epicoccum (Garg et al 1995)
The fungal genera most commonly found in lists of isolated taxa given in literature
are Alternaria Aspergillus Chaetomium Cladosporium Fusarium Penicillium and
Verticullum [Weirich (1989) Tate et al (1990) Guglielminetti et al (1994)
Garg et al (1995) Berner et al (1997) Ciferri (1999)] Some fungi having hard fruiting
bodies represented by sclerotia pycnidia perithecia cleistothecia and stroma could
organize themselves inside the painted layer Many fungal forms having such structures
were identified from our experimental sites viz Emericella nidulans A flavus
Chaetomium sp and Phoma sp etc These structures with little increase in humidity may
cause swelling in the paint film (Garg 1995)
Strains of species of Alternaria and Cladosporium both of them identified on the
mural paintings of the Palace of Schoumlnbrunn are the most common genera isolated from
stone and mural paintings in indoor environments with standard cultivation methods
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
31 Review of Literature
(Ventosa 2004) Saprophytic species of the genus Cladosporium are among the most
abundant fungi isolated in saltern samples Commonly isolated Cyanobacteria belong to
Nostoc and eukaryotic algae to Lyngbya and members of the Chlorophyceae such as
Chlorella Pseudococcomyxa and Pseudopleurococcus [Gorbushina et al (1987)
Calvo et al (1993) Arino et al (1996)]
They grow optimally on media with low water activity due to high salt or sugar
concentrations seem to propagate 70 vegetatively in the salterns and are thus
halotolerantosmotolerant species rather than simple flush-through occurrences
Cladiosporum herbarum was frequently isolated from hypersaline waters dead and dying
plant material air soil food fruit cereals paint and textiles (Ventosa 2004)
C) Algae
Most of the painted areas in temperature climate became covered with green algae
(Pleurococcus Protococcus and Trentopholia) while under tropical conditions blue green
algae of the genera Oscillatoria and Sytonema predominated (Garg 1995) The main
factors which contribute to the growth of algae on wall paintings are the presence of
moisture in the plaster as well as availability of visible light These conditions are quite
prevalent in the tropical climate but in temperature regions also algal growth on wall
paintings have been reported [Tonolo et al (1961) Pietrini et al (1991)]
D) Actinomycetes
Usually literature refers to specific aspects eg the occurrence of cyanobacteria
and algae in caves with natural openings to sunlight or those with artificial lighting fungi
and so forth Actinomycetes have been considered to be mainly confined to soils where
they find their natural habitat but despite intensive studies there are still many gaps in our
knowledge of the role played by actinomycetes in soil processes and biodegrations of
murals cave paintings (Groth et al 1999) In addition halophilic bacteria actinomycetes
and cyanobacteria are also capable of growing on salt-affected mural paintings
(Karbowska 2003)
Monte and Ferrari (1993) reviewed the mechanisms of biodeterioration in tombs
and underground churches The role of actinomycetes in the deterioration of frescoes in
hypogean environments was stressed by Agarossi et al (1985) Monte and Ferrari (1993)
Giacobini et al (1987) described the serious damage suffered by a whole series of famous
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
32 Review of Literature
frescoes in underground environments Actinomycetes were isolated from these mural
paintings located in crypts caves and tombs About 200 strains of actinomycetes were
isolated 60 of which were identified The most frequent species were Streptomyces albus
S cinereoruber S griseolus S vinaceus and some members of the Nocardia genus
Heterotrophic bacteria and actinomycetes were the most abundant microorganisms
on the frescoes of Etruscan tombs (Agarossi et al 1985) Bettini et al (1977) studied
some of the oldest Etruscan tombs (7th to 4th century BC) and found white-grey patinas
and spots from streptomycetes in the mural paintings They related the biodeterioration to
the microclimatic conditions (eg lower temperatures high RH) Monte and Ferrari (1993)
considered that colonization of the mural paintings was the result of selective competitive
and inhibitory dynamics among different microorganisms under different and changing
environmental conditions The pigments excreted by some actinomycetes were responsible
for the violet stains found on the walls of tombs in Tarquinia Similar stains were observed
in one of the Roman tombs the Circular Mausoleum the Necropolis of Carmona Spain
from which a Streptomyces sp producing violet pigments in culture media was isolated
214 Identification of biodeteriogens
The possibility of pigments and biodeteriogens identification in frescos and stone
monitoring is offered mostly by vibrational spectroscopy infrared thermography laser
induced fluorescence (LIF) laser induced breakdown spectroscopy (LIBS) XRF (X-Ray
Fluorescence) IR and UV emission Among them laser based methods allowing for in
situ or remote characterization of artwork surface were applied successfully for
prospecting diagnosis and maintenance (Colao et al 2005) The rep-PCR fingerprinting
of the isolates allowed determination of their genotypic diversity Studies that have
compared rep-PCR genomic fingerprint analysis with DNAndashDNA relatedness studies have
shown that the two techniques yield results that are in close agreement [Nick et al (1999)
Rademaker et al (2000)] These studies therefore suggest that rep-PCR fingerprinting can
be used as a genomic screening method to differentiate at the species level and to select
representatives for DNAndashDNA reassociation experiments (Heymann et al 2003)
The characterisation of bacteria was for example often limited to isolation from
group-specific media followed by microscopy [Sorlini et al (1987) Weirich (1989)
Tate et al (1990) and in more recent studies to morphological and physiological
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
33 Review of Literature
characteristics including miniaturised and automated systems such as API and BIOLOG
[Arroyo et al (1997) Jimmenez et al (2000) and Laiz et al (2000)] or to
chemotaxonomic characteristics [Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
Wagner et al (1994) demonstrated that conventional microbiological efforts can
fail to isolate all microorganisms present in natural samples DNA-based techniques used
to identify microorganisms have revealed only a smaller fraction of bacteria isolated from
artworks (Ward et al 1990 Rolleke et al 1996) Bacterial identification using molecular
techniques especially those including the sequencing of genes coding for ribosomal
16S rRNA is very important to study bacterial communities found on artefacts One such
method is Denaturing Gradient Gel Electrophoresis (DGGE) of PCR-amplified gene
fragments coding for rRNA (Muyzer et al 1993) that allows the separation of partial
16S rDNA amplified fragments of identical length but different sequence due to their
different melting behaviour in a gel system containing a gradient of denaturants
(Jimenez 2003)
Total genomic DNA was purified for 16S rRNA gene sequencing and rep-PCR
using a slight modification of the method of Pitcher et al (1989) as described by
Heyndrickx et al (1996) rep-PCR genomic fingerprinting was performed with the REP-
and (GTG)5 primers (Versalovic et al 1994) using the PCR conditions described
previously by Rademaker et al (1997) Electrophoresis and pattern analysis were further
performed as described by Heyrman et al (2003) 16S rRNA gene sequencing and
phylogenetic analysis were performed as described by Heyrman and Swings (2001)
Phylogenetic trees were constructed using the BioNumerics software (Applied Maths) by
applying the neighbour-joining and maximum-parsimony methods on a multiple alignment
similarity matrix The stability of relationships was assessed by a bootstrap analysis of
1000 datasets For determination of the G+C content and levels of DNAndashDNA
hybridization approximately 1 g biomass was harvested from agar plates DNA was
purified by using a combination of the protocols of Marmur (1961) and
Pitcher et al (1989) as described by Logan et al (2000) The G+C content of the DNA
was determined by HPLC (Mesbah et al 1989) using the further specifications given by
Logan et al (2000) DNAndashDNA hybridization experiments were performed using a
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
34 Review of Literature
modification of the microplate method of Ezaki et al (1989) as described by
Willems et al (2001)
215 Preservation and conservation
Nowadays the conservation and preservation of our cultural heritage is one of the
world main concerns particularly in Europe The increasing need for non-destructive
investigation tools has become a major issue as sampling is in most cases restricted in
view of the value or the uniqueness of the object Artworks as wall paintings in buildings
and monuments of historical interest are affected by environment physical (temperature
and humidity) and biological factors (biodeteriogens) and by human (pollutant releases)
impact and therefore modified over the time The term ldquoconservationrdquo may have many
different meanings in different fields Every intervention directed to the restoration and
safeguard of works of art is commonly considered as a conservation treatment For
example conservation can involve the cleaning procedures set up by chemists or the photo
documentation of the preservation of historical memory For the appropriate conservation
of works of art even the lighting systems in a museum or the control of the visitorrsquos
movements in a site should be monitored Chemical degradation which induces the flaking
of paintings and deterioration from rain wind dust and other environmental causes is
mainly responsible for the weakening of the porous structure and the surface layers of the
materials used in works of cultural heritage (Colao et al 2005)
216 Conservation history
Wall paintings are an integral part of monuments and sites and should be preserved
in situ Many of the problems affecting wall paintings are linked to the poor condition of
the building or structure its improper use lack of maintenance frequent repairs and
alterations Also frequent restorations unnecessary uncovering and use of inappropriate
methods and materials can result in irreparable damage Substandard and inadequate
practices and professional qualifications have led to unfortunate results It is for this reason
that an appropriate document covering the principles of proper conservation-restoration of
wall paintings is necessary
The Venice Charter (1964) has provided general principles for the conservation-
restoration of cultural heritage The Amsterdam Declaration (1975) introducing the
concept of integrated conservation and the Nara Document on Authenticity (1994) dealing
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
35 Review of Literature
with cultural diversity have expanded these principles Taking into account these and
additional relevant contributions such as the ICOM-CC Code of Ethics (1984) Document
of Pavia (1997) and ECCO Professional Guidelines (1997) the aim of this document is
to provide more specific principles for the protection preservation and the conservation
restoration of wall paintings This document therefore reflects basic and universally
applicable principles and practices and does not take into account particular problems of
regions or countries which can be supplemented at regional and national level by
providing further recommendations where necessary
217 Preservation techniques of the mural paintings
The removal of fat salts varnishes and pollutants from the surfaces of the works
of art are mostly done by chemical and mechanical methods At the end of the 19th
century the practices of restoration methods that do not inhibit further future interventions
was considered acceptable During the 1960s several chemicals such as polymeric resins
were synthesized and applied as a consolidation or protection agents The accepted idea
was that these substances could be removed at any time leaving a completely unaltered
substrate On the basis of origin archaeological objects can be classified as follows
(Carretti 2005)
1 Inorganic It includes siliceous and nonsiliceous materials Archaeological materials
produced from stones terracotta ceramics and glass can be included under siliceous
materials whereas objects made of metals can be included under nonsiliceous inorganic
materials Again metal objects can be classified as ferrous metals and non-ferrous metals
Objects made of iron are termed as ferrous metal objects whereas metal objects made from
other than iron is termed as non-ferrous metal objects
2 Organic It includes archival and anthropological materials Again archival materials
include paper bhojapatra tadapatra textiles wooden objects miniature paintings whereas
anthropological objects include bone and ivory leather feather and fur etc
In the past restoration of paintings and other old artwork often involved application
of acrylic resins to consolidate and protect them One of the most important tasks for
modern restorers is thus to remove these layers because it turns out that acrylic resins not
only by drastically changing the optics of the treated artwork but in many cases they
accelerate their degradation The scientists use an oil-in-water microemulsion with the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
36 Review of Literature
organic solvent para-xylene as the oil component The matrix makes the cleaning agent
viscous so that it cannot enter very far into the pores of a painting (Carretti 2005)
Nanoparticle treatment is the logical evolution of the Ferroni-Dini method
Dispersions of kinetically stable Ca (OH)2 nanoparticles in non-aqueous solvents solved
most of the drawbacks of the microsized powders Stable dispersions of calcium hydroxide
have been successfully applied (replacing polymers) as fixatives to re-adhere lifted paint
layers during many restoration workshops in Italy and in Europe as a consolidant The
FerronindashDini method (two steps the application of a saturated solution of ammonium
carbonate (NH4)2CO3 and the treatment with a barium hydroxide solution Ba(OH)2 also
called the barium method has long been the acknowledged method for the removal of
salts that threaten paintings reinforcing at the same time the porous structure However
commercially available carbonates and hydroxide powders have dimensions of several
micrometres much larger than the pores on the paint surface This means they donrsquot
penetrate the painting well and there is also a risk of damaging the artwork by a white
glaze forming on the surface (Berger 2006) Restoration should provide the reinforcement
of the porous structure and the consolidation of the surface layer of arte facts A few
simple principles can be considered to define the most appropriate restoration method
1) The treatment should be reversible so that one can revert to the original status of the
work of art at any desired time
2) All the applied chemicals must ensure the maximum durability and the chemical
inertness
3) The applied chemicals must invert the degradation processes without altering the
chemical composition of the artefacts and their physico-chemical and mechanical
properties (Baglioni 2006)
218 Commercial preservative used for preservation of mural paintings
Cleaning was done using soft brushes vacuum cleaner and Gumma paine (dough)
a natural latex sponge Areas near the window were very dirty with black soot and were
cleaned with micro fibrous cloths moistened with synperonic N (surfactant alkyl phenol
ethoxylate based on nonyl phenol) and neutralized with clean water In several places the
paint layers had separated from the substrate (exfoli-ation) In that cases loose paint flakes
were stuck back using Paraloid B72 (10 solution in ethanol) as sparingly as possible
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
37 Review of Literature
Paraloid was injected with syringe behind the exfoliated area twice pushed and held back
with Melinex (polyester film) until fixed on the third application (Bionda et al 2002)
In a period of significant growth of molds and intensive efforts to stop the mold
contamination some of the lines of certain paintings were obscured or faded Solutions of
ethanol formalin 91 and Thiabendazole (TBZ) were used but they were not very
effective Para-formaldehyde fumigation was adopted beginning in 1981 to establish an
emergency treatment sensitivity of microorganisms from studied samples was tested
against Desogen by adding 1-3 (v v) in serial dilutions The best concentration
3 (vv) was applied with a brush to prevent spreading of the spores In order to overcome
the problem of fungal attack suitable fungicides carbendizeme or kiroxy-I or 5 solute of
N formaldehyde can be used Shellac solution in spirit or 2 solution of polyvinaycletate
in toluene can be used as preservative and consolidantsTo control insect and fungal attack
fumigants like pyrethrum DDT or 5 solution of sodium penta chlorophenate in kerosene
oil 2 to 5 solution of PVA in toluene or 2 to 5 solution of paraloid B-72 in toluene or
acetone be used (Miura 2009) Microclimatic conditions constitute a critical factor in the
conservation of cave paintings The unstable microclimatic condition is one of the factors
that always affect the state of conservation of mural paintings In the environmental-
monument system knowledge of the functional environment and climatic conditions of the
surroundings are necessary for the identification of causes of decay (Singh 2011)
Furthermore the risk of formation of indoor bioaerosols in residential and public
buildings (offices schools museums etc) has attracted interest in the last years due to
socio-economic as well as sanitary reasons (Ripka 2005) Thus it is important in aspects of
health and maintenance of Cultural Heritage to analyse the complete microflora to further
develop biocides for harmful microorganisms and methods for restoration of damaged
objects of art The biocidal testing was carried out on one representative algal species of
the two classes of algae viz Chlorococcum sp (green) and Chroococcus sp (blue-green)
found to be common in all the samples Efficiency tests were carried out both in liquid as
well as solid media containing algal suspensions by adding a biocide solution of known
concentration and determining the growth of the microorganism after the incubation
period The biocides used for the past studies were
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
12 Review of Literature
are seen in the most beautiful temple - Cave 16 Kailasanatha circa 760 - 860 AD Some
Jain temples - Cave 32 (Indra Sabha) Cave 33 - contain remnants of valuable murals from
800 - 1000 AD - this artwork marks the end of ancient period in the Indian art and
beginning of medieval art (Baskaran 1975)
Figure-25 Ellora caves
There are surviving mural paintings from the 17th century onwards in Rajasthan
The verdant Pahari hills saw the finest continuation of the tradition of murals in India The
18th and 19th century paintings on the walls of the Rang Mahal in Chamba are among the
best surviving examples of Pahari murals The 18th century paintings on the walls of the
Viranchinarayan Temple at Buguda are some of the finest surviving murals of that period
in India
Figure-26 Paintings on the walls of the Rang Mahal in Chamba
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
13 Review of Literature
The most important sites of rock paintings in North India are at Bimbetka Gwalior
Tikla Ayra Bhanpura Rampura Singhauli Bhojpur Adamgrh Delware and Mirzapur
In South India they are found at Mehaboob Nagar (Andhrapradesh) Edakkal Marayoor
Perimkadavila (Kerala) Mallampadi (Tamilnadu) and Bellary (Karnataka)These
paintings were considered as the early models of mural paintingsThe mural painting of
Sittannavasal Badami Lepakshi Tanjore Vijayanagar and Kerala has a lot of similarities
(Sasibhoosan 1987)
25 South Indian murals
South India also got rich tradition of mural paintings In the reign of Cholas
Vijayanagaras and Nayakas this art reached the climax The Deccan art of Bijapur
Hyderabad and Golconda schools were influenced by the Mughal traditions and later by
European idiom Maratha murals are also shaped under the Mughal traditions and
employed oil as medium The Mural art of Kerala vividly depicted on the walls of temples
and monuments show the traces of European affinity In Tamil Nadu almost all the extent
examples of frescos have been done on rock surfaces and stone walls This is a crucial
factor in determining the quality of frescos (Havell 1982) The ceiling of the Virupaksha
temple in Hampi is covered with paintings of the 15th century The paintings on the ceiling
of the mandapa of Lepakshi temple are some of the finest mural paintings of the medieval
period in India Legends associated with Siva and Parvati Krishna and Rama were painted
on the walls of palaces and temples in Kerala from the 16th to 19th century Mural
paintings were made on the walls of all the palaces within the magnificent Orccha fort The
Raj Mahal was completely adorned with mural paintings of the 17th century
Figure-27 Virupaksha temple in Hampi
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
14 Review of Literature
Figure-28 Ceilings of Virupaksha temple Hampi
The murals on the walls of the navaranga (the central pillared hall) depict stories
from Bhagavatha and are excellent examples of 19th
century Mysore paintings The
Mallikarjunaswamy temple on the hill is one of the Panchalingas of Talakad and the
temple has a beautiful mural painting on the wall of the temple The Dariya Daulat Bagh
has excellent mural painting (Sasibhoosan 1987)
Figure-29 Paintings on the walls of Jagan mohan palace Mysore
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
15 Review of Literature
Figure-210 Painting of Raja woodeyar era
Kerala mural paintings are the frescos depicting mythology and legends which are
drawn on the walls of temples and churches in South India principally in Kerala Ancient
temples churches and palaces in Kerala South India display an abounding tradition of
mural paintings mostly dating back between the 9th to 12th centuries The murals of
Thirunadhikkara Cave Temple (now ceded to Tamilnadu) and Tiruvanchikulam are
considered the oldest relics of Keralarsquos own style of murals Fine mural paintings are
depicted in temples at Trikodithanam Ettumanur Vaikom Pundarikapuram
Udayanapuram Triprangode Guruvayoor Kumaranalloor Aymanam the Vadakkunathan
temple in Trichur and the Sri Padmanabhaswamy temple at Thiruvananthapuram Other
mural sites are in the churches at Edappally Vechur Cheppad and Mulanthuruthy and at
palaces such as the Krishnapuram Palace near Kayamkulam and the Padmanabhapuram
Palace
Figure-211 Kerala murals
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
16 Review of Literature
Figure-212 Murals paintings of Kerala temples
There are wall paintings in Badami in the Bijapur district Karnataka Some
excellent paintings exist in the Jain caves at Sitanavassal in Puddukkottai District of Tamil
Nadu Tamil Nadu gave exuberant and glorious expression to themes relating to Siva in the
temples of Panamalai and Kailashanatar in Kancheepuram In the 9th century Jain cave of
Sittannavasal in Tamil Nadu there is a marvellous lotus pond painted on the ceiling In
the heart of the Brihadeeswara temple in Thanjavur Tamil Nadu protected by massive
walls of stone are the finest paintings of the theme of Siva ever painted towards the end of
the 10th century (Sivaramamurthi 1992)
Figure-213 Kancheepuram Mural paintings
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
17 Review of Literature
Figure-214 Sculpture of Mahabalipuram
26 Methods of mural painting
In the history of mural several methods have been used The Buon fresco technique
consists of painting in pigment mixed with water on a thin layer of wet fresh lime mortar
or plaster The pigment is then absorbed by the wet plaster after a number of hours the
plaster dries and reacts with the air it is this chemical reaction which fixes the pigment
particles in the plaster After this the painting stays for a long time up to centuries in fresh
and brilliant colors A Secco painting is done on dry plaster The pigments thus require a
binding medium such as egg (tempera) glue or oil to attach the pigment to the wall
Mezzo-fresco is painted on nearly-dry plaster which is defined by the sixteenth-century
author Ignazio Pozzo as ldquofirm enough not to take a thumb-printrdquo so that the pigment only
penetrates slightly into the plaster Ancestral Hopi village archaeologists found that
fourteen kivas had painted murals and multiple layers of murals on the walls some with up
to twenty-seven layers of murals (Saturno 2006)
The colors used in painting are generally obtained from plants and minerals
Among them only such colors which are lime resistant are suitable for mural painting The
selection of proper colors for a mural painting is an important part of the work as the
longevity the painting depends on it Only mineral colors are preserved for a long time
which could be the reason for use of those colors in early days As per ldquoShilpa ratnardquo and
ldquoAgnipuranardquo the colors used in mural painting are white black red yellow blue and
green Yellow and red are from yellow ochre and red ochre Blue is generally indigo or
china blue White is the prepared wall and black is the carbon soot Mural paintings have
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
18 Review of Literature
survived centuries only on account of the identification and use of those colors which does
not have any reaction with lime (Miraseth 2006)
Originally three types of brushes were made and used flat medium and fine Flat
brushes were made from hairs behind calfrsquos ear the medium from the bottom of goats
belly and the fine brush from delicate blades of grass However in due course of time and
change use of easily available brushes from commercial market and shading of the
original colours can be distinctively noticed The use of blue colour is also noticed over the
passage of time The paintings have been brought down from the walls to plywood cloth
paper and other frames for easy to make and use purposes (Chakarabarti 1980)
27 Themes of mural painting
The subjects and themes in the murals are centered on the Hindu pantheon of Gods
and Goddesses drawn from description in the invocatory verses or Dhyana Slokas More
common representations are of Vishnu in different incarnations Ganesha and
manifestations of Siva We see murals in the Pallimanna Siva Temple devoted to Siva-
Parvatirsquos marriage the Ramayana Story being narrated on the walls of the Mattancheri
palace in the Sankara Narayana the Mahabharata is retold Murals are various scenes from
the Hindu epics and also the frolics of Lord Krishna
It would be interesting to bring into account the influence of the mural paintings on
Christianity On various churches like the St Georgersquos Orthodox Church has Christian
murals bringing out biblical characters and narrating stories from the scriptures Mar
Sabore and Afroth Church at Akapparambu in the outskirts of Ernakulam also have murals
of scenes from the bible Interestingly StMaryrsquos Church at Kanjoor has on both sides of its
entrance a battle scene between the armies of Tipu Sultan and of the English East India
Company It is also apparent that the history of Kerala Murals has its origin in the temple
walls and thus a study of Kerala Murals is not complete without pondering on the
architecture of Kerala its association with the murals (Warrier 2011)
28 Technique used in mural paintings
Indian murals executed on walls of caves structural temples walls of palaces were
based on highly developed techniques Mural painting is a composite structure of these
three basic layers the support the ground and the pigment layer In case of wall painting
the wall itself is the support This is followed by the layer or layers of plaster which
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
19 Review of Literature
constitute the ground The pigment layer is the one which contains the picture The support
is the wall which may be rock surface in a cave or a structural one These stone surfaces
which serve as carriers are rough or uneven This unevenness is itself an advantage as it
provides ldquotoothrdquo to hold the plaster on the surface The uneven surface of the wall has to be
made uniform with layers of plaster in successive gradation of fineness There is generally
one layer of rough plaster followed by one or more layers of fine plaster Ground or plaster
is a term used to mean the surface material of a wall or building which is applied as a
plastic mass made by mixing certain materials with water letting the mass set by drying
carbonation or hydration The active or setting components of plaster are commonly clay
which sets by drying lime which sets by carbonation gypsum and pozzolana which sets by
hydration (Mini 2010)
There are different mixtures for rough plaster In all the mixtures clay limestone
lime and shells in powdered form serve as the matrix The particles of which are held
together by the organic materials like gum glue extracts from barks etc are in fact
adhesives The fine plaster layer requires more careful preparation because it is the layer on
which the pigments are laid to make the picture ldquoShilparatnardquo suggest a mixture of conch
Oyster shells or white clay with gum of neem or slaked lime and coconut water Here the
consolidation is effected by the carbonation of slaked lime ie it absorbs carbon dioxide
from air and becomes carbonate Mural paintings were lime-washed from the 17th until the
beginning of 19th century A few paintings in vaults were never lime-washed for example
at Taby and Floda painted by the medieval painter Albertus Pictor (Mini 2010)
All the paintings have certain basic common characteristics There has to be a wall
or rock surface called support over which the artist goes to work A plaster base called
ground of varied thickness is laid on the support The ground may consist of one or more
layers The strength and life of the whole mural depended up on this ground over which the
painting was done It is the process of applying the final painting on the ground determines
the character of the mural whether it is fresco or tempera The mural painting is done
usually by creating wall surface free of any previous oil or paint by using solvent or by
sand blasting The brick wall is first plastered with mixture of lime and sand in the ratio of
12 A mixture of egg yolk vinegar oil colour is used in dry plaster
There are at least six stages before a Kerala Mural Painting is complete Lekhya
Karma is the first stage where sketching by pencil or crayon is done The second stage is
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
20 Review of Literature
the Rekha Karma which enhances the outlines of the sketching done The third stage called
Varna Karma breathes life into the painting with its colours Here all colours are
appropriately filled in The colouring of the human figures is done according to the
characters and their common virtues The divine and noble characters (Saatvik) are painted
in green those inclined towards power and wealth (Raajasik) is painted in shades of red
lowly mean characters (Tamasik) in white and demons in black In the fourth stage or the
Vartana Karma shading is done Fifth stage called the Lekha Karma brings us to the final
outline of the painting which is usually in black The final and the finishing touches stage
are called Devika Karma (Warrier 2011)
29 Dyes used in mural painting
Indians have been considered as fore runners in the art of natural dyeing Natural
dyes find use in the colouring of textiles drugs cosmetics etc Owing to their non-toxic
effects they are also used for colouring various food products In India there are more
than 450 plants that can yield dyes In addition to their dye-yielding characteristics some
of these plants also possess medicinal value Though there is a large plant resource base
little has been exploited so far Due to lack of availability of precise technical knowledge
on the extracting and dyeing technique it has not commercially succeeded like the
synthetic dyes (Siva 2007)
The color materials on the mural paintings in ancient India were derived from the
natural materials like terracotta chalk red ochre and yellow ochre mixed with animal fat
The dyes for painting is prepared such as white from lime Black from carbon soot of
lamps Red and yellow from minerals Blue from indigo ferra Deep red from lac A fine
coating of resin is done after the painting in order to make a shining appearance Egg yolk
and vinegar was mixed with oil colors and painted on dry plaster (Krishnakumar 1999)
Although plants exhibit a wide range of colours not all of these pigments can be
used as dyes Some do not dissolve in water some cannot be adsorbed onto fibres whereas
others fade when washed or exposed to air or sunlight It remains a mystery why plants
reward us with vibrant dyes India has a rich biodiversity and it is not only one of the
worldrsquos twelve mega diversity countries but also one of the eight major centres of origin
and diversification of domesticated taxa It has approximately 490000 plant species of
which about 17500 are angiosperms more than 400 are domesticated crop species and
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
21 Review of Literature
almost an equal number their wild relatives Thus India harbours a wealth of useful
germplasm resources and there is no doubt that the plant kingdom is a treasure-house of
diverse natural products One such product from nature is the dye (Siva 2007)
Many natural dyestuff and stains were obtained mainly from plants and dominated
as sources of natural dyes producing different colours like red yellow blue black brown
and a combination of these Almost all parts of the plants like root bark leaf fruit wood
seed flower etc produce dyes It is interesting to note that over 2000 pigments are
synthesized by various parts of plants of which only about 150 have been commercially
exploited Nearly 450 taxa are known to yield dyes in India alone of which 50 are
considered to be the most important ten of these are from roots four from barks five from
leaves seven from flowers seven from fruits three from seeds eight from wood and three
from gums and resins Some important dye-yielding plant habitats their distribution and
colouring pigment (Siva 2007)
The dye is generally prepared by boiling the crushed powder with water but
sometimes it is left to steep in cold water The solution then obtained is used generally to
dye coarse cotton fabrics Alum is generally used as a mordant Flowers of Butea
monosperma (Lam) Taubert yield an orange-coloured dye which is not fast and is easily
washed away For the purpose of colouring the material is steeped in a hot or cold
decoction of the flowers A more permanent colour is produced either by first preparing the
cloth with alum and wood ash or by adding these substances to the dye-bath The dye
indigo is produced by steeping the plant in water and allowing it to ferment This is
followed by oxidation of the solution with air in a separate vessel Mallotus philippinensis
muell yields an orange colour used for dyeing silk and wool To prepare the annatto dye
from B orellena the fruits are collected when nearly ripe The seeds and pulp are removed
from the mature fruit and macerated with water Thereafter they are either ground up into
an lsquoannatto pastersquo or dried and marketed as annatto seeds Sometimes when the seeds and
pulp are macerated with water the product is stained through a sieve and the colouring
matter which settles out is collected and partially evaporated by heat and finally dried in
the sun (Sowbhagya 2002)
The predominant colors used in rock art and cave art are black (from charcoal soot
or manganese oxide) yellow ochre (limonite) red ochre (hematite or baked limonite) and
white (kaolin clay burnt shells powdered gypsum or powdered calcium carbonate) All of
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
22 Review of Literature
theses pigments may be used on leather or raw hide as well Early cave art in Seminole
Canyon was monochromatic in red and as culture grew more sophisticated the color
palette expanded Blue Orange Brown Green and Purple are the most common colours
used in Ajantha murals White Pink Gold are occasionally represented mineral earths
containing ferric oxide and copper carbonates were used as source of red yellow and green
colours There is also evidence to establish that root of Rubia cardifolia and leaves of
Indigofera tinctoria were used as source for red and blue colours (Nayer et al 1999)
Many colors of pigments were obtained from both organic and inorganic sources in
ancient times and used to paint various surfaces such as braintan leather clothing and
accoutrements rawhide the human body etc Blue color was obtained from powdered
azurite and lapis duck manure and certain clays Fine Blue-green clay was obtained from
deposits near Mankato Michigan Organic sources of blue include Turkeys Tail a
greenish blue polypore that grows on dead decaying wood (not tannish ones) Native
Americans get Indigo from either Guatemala or Ecuador which was traded well up onto
Kansas long before the Spanish ever set foot here American Indigo has purple tones to it
but IndianJapanese indigo has green tones Berries and crushed flowers were also used to
obtain blue color by rubbing the plant material directly on the leather
An organic source of red was Cochineal It was native west of the Mississippi and
is produced from the bodies of small insects that grow on the prickly pear cactus Ladys
Bedstraw gives a good vermillion red color Harvest the roots dry them out clean the mud
etc off of them and then grind the roots really fine then soak them to extract the red
coloring The key here is drying the root first Blood was also used as red pigment Pucoon
roots also yield a red pigment (Smith 2002) Red ochre the reverse original red colours are
due to variations in iron oxide (or) calcite content and to redox conditions in the firing
produced Brown coloured ceramics owe their colour to maghemite and must be
considered as a fabrication defect due to the position of the ceramic piece in a zone where a
reducing atmosphere prevailed in the course of firingRed pigments were produced from
iron oxides like hematite or limonite and from ochre Hematite was the most frequently
used mineral It occurs in the form of aggregates of small red crystals or in the form of
bigger black crystals which are difficult to crush white was obtained mostly from
kaolinite or illite (Clottes et al 1990)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
23 Review of Literature
210 Biodetoriation of mural paintings
Historic items often contain natural biodegradable materials and have histories of
exposure to moist conditions These two conditions make them amenable to microbial
attack Microbial colonization may damage the building or the cultural asset
(Salonen 2001) Biodeteriogens are organisms involved in deterioration of artifacts They
are very specific for each type of artifact in accordance with its chemical structure and
environment They also have different nutritional requirements and act directly or
indirectly on the substrate The adhesion of microorganisms to a substrate is the result of
cell hydrophobicity and of excreted polymeric substances contained by sheaths capsules
and slimes (Colao 2005)
The surviving wall paintings and decorations in subterranean environments around
Malta are rather scarce (Buhagiar 1986 1993 1998) These include those at St Paulrsquos
Catacombs (Zammit 2008) St Agatharsquos Crypt and Catacombs (Camilleri 2001)
San Catald Catacombs Tac-Cghaqi Abbatija tad-Dejr (Buhagiar 1993) all in Rabat the
cave-sanctuary in Mellieħa (Buhagiar 1987) and the Ħal Saflieni Hypogeum in Paola
(Pace 2000) Previous studies conducted on wall paintings and decorations in Maltese
Palaeo-Christian Catacombs have involved their manufacturing techniques (Muscat 2005)
However to date limited systematic studies have been conducted into the biodeterioration
in Maltese Palaeo- Christian Catacombs The only such studies ever conducted in Malta
concerned the biodeterioration of works of art in catacombs have been carried out at St
Agatharsquos Crypt and Catacombs in Rabat (Zammit et al 2008 Psaila 2006)
Microorganisms can be responsible for the destruction of monuments buildings
and cultural heritage assets including the decay of concrete cement stones mural
paintings etc These microorganisms are not only related with biodeterioration but water-
damaged indoor building materials are frequently colonized by complex bacterial
communities and may emit mixed bioaerosols into the indoor air (Jimenez 2000) It is
well known that mural paintings are colonized by micro-organisms and can be severely
damaged by such growths (Ciferri 1999) A large number of fungal (gt50) and bacterial
taxa (70) have been detected in indoor environments Over 50 bacterial species and 14
genera novel to science were reported in the past 10 years from indoor air and historic
items indicating bacterigravea in these enviroments are as yet only fragmentarily known
(Salonen 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
24 Review of Literature
Traditionally the study of microflora which causes this biodeterioration was based
on classical cultivation methods that were mainly useful to study the physiological
potential of microorganisms but do not provide information on all microbial communities
to be found in excavated artifacts Indeed many studies using culture-independent
techniques which cultivate microorganisms from different environments may often
represent only minor components of the microbial community as a whole It is generally
accepted that cultivation methods recover less than 1 of the total microorganisms present
in environmental samples (Ward et al 1990 Amann et al 1995) Hence microbial
investigations based only on cultivation strategies cannot be regarded as reliable in terms
of reflecting the microbial diversity present in objects of art (Osburn et al 2011)
Early workers suggested that the presence of living microorganisms on stone
increased its susceptibility to damage through their water-binding capacity It has recently
been reported that the mineralogy porosity surface roughness and capacity to collect
water and organic materials control its bioreceptivity and tendency to biodeterioration
(Diakumaku 1995) In addition environmental factors as temperature light pH and
relative humidity affect the number and type of colonising species (Tiano et al 1995) and
hence the progress of colonisation Biofilms on decayed stones consist on mixed microbial
populations embedded in a polymeric matrix Fungi algae filamentous and unicellular
bacteria are found in these complex communities A variety of bacteria have been isolated
from different stone samples confirming the dominance of Gram-positive organisms
especially spore-forming bacteria such as Bacillus and filamentous actinomycetes
(Ripka 2005)
In cultivation studies of deteriorated mural and rock paintings bacterial isolates
have frequently been attributed to the genus Bacillus (Weirich 1989 Tate and Rebrikova
1991 Gonzalez et al 1999 Heyrman et al 1999 Jimenez et al 2000) Other studies that
have included DNA-based techniques to characterize the bacterial community involved in
biodeterioration have shown that a substantial part of the bacterial population is made up of
so far unknown species (Altenburger et al 1996 Rolleke et al 1996 Gurtner et al 2000
Heyrman and Swings 2001) (Heymann et al 2003)
Many potential mycotoxin producers have been detected in air and items from
indoor environments with histories of exposure to moisture for example species of
Acremonium Alternaria Aspergillus Chateomium Fusarium Eurotium Paecilomyces
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
25 Review of Literature
Penicillium Scopulariopsis Stachybotrys Trichoderma Verticillium and Wallemia
(Peltola et al 2001 Pieckova et al 2001) Not all strains of one species produce
mycotoxins and different strains may produce different toxins Whereas toxin producing
strains are frequent in crops and outdoor vegetation toxin producing isolates from indoor
environments and non living assets have only been reported of the species Aspergillus
versicolor (Nielsen et al 1998) Stachybotrys chartarum Nikulin (1997) and
Trichoderma harzianum (Peltola et al 2001) Streptomyces griseus strains producing
valinomycin occur in environments where humans can get exposed
(Andersson et al 2002) The biological properties and toxicity mechanisms of cereulide
were identical to those by valinomycin (Mikkola et al 1999 Salonen et al 2001)
The genus Paenibacillus was first proposed by Ash et al (1993) and its description
was emended by Shida et al (1997) The genus Paenibacillus is under intensive taxonomic
investigation with ten species having been formally described in the last year Heyrman amp
Swings (2001) isolated a strain originally classified as Paenibacillus sp LMG 19508
from biodeteriorated mural paintings in the Servilia tomb at the Roman necropolis of
Carmona in Seville Spain (Smerda et al 2006) Building stone and wall paintings contain
a variety of hydroscopic salts including carbonates chlorides nitrates sulfates etc
dispersed within the porous material or locally concentrated These salts are solubilised
and migrate with the water in and out of the stone Due to changes in physical parameters
the so called salt efflorescences appear on the surfaces providing extremely saline
environments and building niches for settlement of halophilic microorganisms Halite and
other hygroscopic salts can retain considerable quantities of moisture when entrapped in
the building materials and thus favouring the bacterial growth (Ripka 2005)
It is demonstrated that water-damaged indoor building materials contained
substances of microbial origin extremely toxic to eukaryotic cells and large quantities of
several microbial species known to be potentially toxic or immunopotentiating These
include peptidoglycans Gram-negative endotoxin β-13-D glucans lipoglycans and
teichoic acids and mycotoxins (Jimenez 2000) In turn these microorganisms can mediate
the crystallization process These crystallizations can produce destructive effects Some
salts may crystallize or recrystallize to different hydrates which occupy a larger space and
exert additional pressure producing cracking powdering and flaking
(Jimenez and Laiz 2000)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
26 Review of Literature
211 Types of deterioration on mural paintings
The frescos represent a variety of ecological niches where primary colonization is
due to photoautotrophic and chemolithoautotrophic microorganisms followed by
secondary colonization due to heterotrophic bacteria that obtain nutrients from various
sources (metabolites of autotrophic bacteria airborne organic contamination animal faeces
and organic compounds in the paint layers themselves) Microbial-induced deterioration
processes cause structural as well as aesthetic damage to wall paintings such as the
discoloration of materials the formation of crusts on surfaces and the loss of material
(Sarro et al 2006 Osburn et al 2011) Halophilic bacteria and archaea were thought to
be found only in extreme environments like salt lakes or black smokers However it has
been shown that mural paintings and stones are a common habitat for extremely salt
tolerant and moderate halophilic (Ripka 2005) Microbial induced deterioration processes
can cause different kinds of alterations such as discolouration of materials the formation of
crusts on surfaces and the loss of material which leads to structural damage (Ripka 2005)
First of all microorganisms can cause severe problems due to the excretion of aggressive
metabolic products such as organic or inorganic acids Secondly material components can
be used as substrates for microbial metabolism Exoenzymes such as cellulases proteases
tannases beta-glucosidase produced by fungi and bacteria are responsible for hydrolysis of
cellulose and proteins Further examples are mechanical processes caused by swelling and
shrinking of slime or mycelia penetrating inside plaster of the painting resulting in loss of
cohesion and detachment of the paint layer (Rolleke 1996 Gurtner et al 2000)
Table-21 Microbial damage on mural paintings (Rolleke 1996)
S No Damage Microbial activity
1 Green brown red grey
surface layers (patinas)
Pigments produced by microorganisms (intra-or
extracellular) as chlorophyll and carotinoids
2 Dislodging of painting layers Use of organic binders as nutrient and energy
source
3 Acid attack of carbonates Acid produced by fungi or bacteria
4 Discolouration of pigments Redox-reactions induced by fungi and
bacteria
5 Loss of paint layer Growth of microorganisms deep into the plaster
6 Hydrolysis of synthetic
polymers Chemoorganotrophic activity of bacteria and fungi
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
27 Review of Literature
Discolorations are caused by excretion of pigments and microbiologically induced
reductionoxidation-processes (Krumbein et al 1990) Degradation of the bindings is
followed by reduction of stability Oxidation of ammonium and reduced sulphur
compounds results in acidification of the environment such as Sulphuric acid and the
variety of organic acids produced by the heterotrophs cause solubilization of calcareous
binding material and chelation of metal ions (Bock et al 1993) It is now well recognised
that wall paintings can be deteriorated by microorganisms (Ciferri 1999)The growth of
microorganisms essentially results in two types of damage aesthetic and structural
Aesthetic damage implies pigment discoloration stains and formation of a biofilm on the
painted surface Structural damage is observed as cracking and disintegration of the paint
layer formation of paint blisters and degradation of support polymers or of glues and
binders resulting in detachment of paint layer from the support The colonization of mural
paintings by bacteria and other microorganisms can have different causes Provided that
favorable environmental conditions occur nutrients for heterotrophic bacteria and fungi
can be available from metabolites of autotrophic bacteria from airborne contamination and
dripping water from animal faeces but also from organic compounds in the paint layer
itself
212 Methods of studying biodeterioration
It is now well recognized that wall paintings may be deteriorated by
microorganisms as established by several studies that linked the observed damage with the
microbial community present as reviewed by Ciferri (1999) Despite this knowledge a
reliable characterization of bacteria associated with such damage is often lacking To
obtain greater insight into the bacterial community involved in biodeterioration of mural
paintings three sites (from the necropolis at Carmona Spain and the Saint-Catherine
chapel of the castle at Herberstein Austria) were sampled In previous studies from these
sites 385 isolates were analysed by fatty acid methyl ester GC and representatives of
different fatty acid clusters were further studied by 16S rRNA gene sequencing
(Heyrman and Swings 2001) Several of these representative strains showed the highest
sequence similarity with members of the genus Arthrobacter (Heyrman et al 2005)
Jimenez and Samson (1981) analysed the microbial flora of a large fresco painted
in the late 1920s in the monastery ldquoSanta Maria de la Rabidardquo (Huelva Spain) exhibiting
two types of deterioration white efflorescence and green-to-black stains
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
28 Review of Literature
Tate and Rebrikova (1990) thought autotrophic nitrifying bacteria to be the first colonisers
of damaged frescoes and building materials in the cathedral of the nativity of the Virgin in
the Pafnutii-Borovskii monastery (Russia) The bulk of research on biodeterioration of
mural paintings has focused on explaining the observed phenomena by analysing the
microflora present Following this approach a precise characterisation of the
microorganisms using a polyphasic approach was never the first goal
Only a few studies included genomic fingerprinting (16S rDNA sequence analysis)
for the characterisation of bacteria associated with damage on mural paintings
[Rolleke (1996) Pinar et al (2001)] Previous studies based on culture-dependent
techniques showed that the flora present on frescos are fungi (predominant species of
Penicillium Aspergillus Cladosporium and Engyodontium) (Guglielminetti et al 1994)
bacteria (predominant species of Bacillus Arthrobacter Micrococcus Streptomyces and
Pseudomonas) (Heyrman et al 1999) cyanobacteria and eukaryotic algae (species of
Nostoc Lyngbya and Chlorophyceae) (Arino et al 1996 Calvo et al 1993) The killing
effect of an antimicrobial agent on a microorganism can be assessed in several ways
(1) Lethal activity may be expressed as the rate of killing by a fixed concentration
of drug under controlled conditions This rate is determined by measuring the number of
viable bacteria at various time intervals The resulting graphic depiction is known as the
time-kill curve Bacterial killing rates are in part dependent on the class of antibiotic and
the concentration of this agent With certain classes of antibiotics (eg aminoglycosides
and fluoroquino-lones) the rate of killing increases with increased drug concentrations up
to a point of maximum effect This is termed concentration-dependent bactericidal activity
In contrast the killing rates of szlig-lactam agents and vancomycin are relatively slow and
continue only as long as the concentrations are in excess of the MIC This rate of killing is
termed time-dependent bactericidal activity
(2) The minimal concentration of drug needed to kill most of the viable organisms
after incubation for a fixed length of time (generally 24 hours) under a given set of
conditions is the most common estimation of bactericidal activity and is known as either
the minimal bactericidal concentration (MBC) or the minimal lethal concentration (MLC)
It will be referred to in this document as the MBC Unfortunately the definition of the
MBC (999 killing of the final inoculum) is somewhat arbitrary and separates the
bacteria into two populations ndash a segrega-tion which might not have biological relevance
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
29 Review of Literature
The determination of the MBC moreover is so subject to methodologic variables that the
clinical relevance of MBCs is nearly impossible to assess particularly for certain pathogen
and drug combinations (eg Staphylococci and beta-lactam agents)
(3) The serum of a patient receiving an antibiotic may be tested against the
infecting microorganism This can be done using time-kill curve methodology (ie serum
bactericidal rate) or using dilution methodology (ie serum bactericidal titer) The
principles of these methods as well as the influence of biological and technical factors are
similar (Barry et al 1999)
213 Microbial flora associated with deteriorated mural paintings
A great deal of research has been done in this field mainly by using cultivation dependent
methods However by using culture-dependent methods only a very small proportion of
microorganisms can be obtained Far less than 1 of organisms in the environment can be
cultivated by standard cultivation techniques (Pace 1996) Recent studies have shown that
culture-dependent techniques yielded mainly sporeforming bacteria suggesting that plating
leads to an over estimation of the number of spore-forming bacteria A wide number of
investigations have shown that in addition to chemical and physical processes
microorganisms play a major role in degradation of objects of art such as paintings stone-
works wood paper masonry leather parchment glass and metal (Ripka 2005)
A) Bacteria
In general growth of diverse organisms on mural paintings is supported by
humidity slight alkaline pH values and the presence of organic and inorganic nutrient
sources (Weirich 1989) In mural paintings pigments are suspended in water or oil often
binders such as casein and milk are used and they are supplied on the damp lime plaster
(Ciferri 1999) The calcium carbonate formed on contact with air consolidates the
pigments Thus frescos contain mainly inorganic components While chemoautotrophic
nitrifiers and thiobacilli obtain their energy for growth by oxidizing ammonium and
reducing sulphur-compounds respectively heterotrophic bacteria and fungi depend on
organically bound carbon [Tate et al (1991) Lazar (1971) Petushkova et al (1986)
Jimenez et al (1981)] Thus primary colonization of photoautotrophic Cyanobacteria
chemolithoautotrophic nitrifying bacteria and sulphuric acid producing thiobacilli represent
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
30 Review of Literature
the first supply of organic matter The death and lysis of such bacteria promotes the
secondary settlement of heterotrophic bacteria and fungal populations (Calvo et al 1991)
Bacteria may derive from plants or pollen as many sequences obtained in this study
gave high score similarities with bacteria isolated from plants like Moraxella osloensis
Enterobacter cloace Enterobacter agglomerans and Pantoea endophytica Bacteria may
also derive from animal faeces like flies Bacillus Pseudomonas Aeromonas and Panteoa
(Ripka 2005) As Lazar and Dumitru (1973) reported studying mural paintings in a
Romanian monastery the genera Bacillus Arthrobacter and Pseudomonas have been
proved to produce salt efflorescences and were even considered to cause the blanching
phenomenon of frescoes (Jimenez et al 2000) Predominant bacterial genera are Bacillus
Streptomyces Arthrobacter Micrococcus and Pseudomonas [Weirich (1989)
Tate et al (1990) Arroyo et al (1997) Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
B) Fungi
It may be concluded that there is wide variety of fungal forms present on mural
paintings but Aspergillus and Alternaria were found dominating from all the experimental
sites next to them were Cladosporium Drechestera Fusarium Curvularia Chaetomium
Memnoniella Mycelia sterelai Pencillium Emericella Stachybotrytis Trichoderma
Phoma Monodictys Humicola and Epicoccum (Garg et al 1995)
The fungal genera most commonly found in lists of isolated taxa given in literature
are Alternaria Aspergillus Chaetomium Cladosporium Fusarium Penicillium and
Verticullum [Weirich (1989) Tate et al (1990) Guglielminetti et al (1994)
Garg et al (1995) Berner et al (1997) Ciferri (1999)] Some fungi having hard fruiting
bodies represented by sclerotia pycnidia perithecia cleistothecia and stroma could
organize themselves inside the painted layer Many fungal forms having such structures
were identified from our experimental sites viz Emericella nidulans A flavus
Chaetomium sp and Phoma sp etc These structures with little increase in humidity may
cause swelling in the paint film (Garg 1995)
Strains of species of Alternaria and Cladosporium both of them identified on the
mural paintings of the Palace of Schoumlnbrunn are the most common genera isolated from
stone and mural paintings in indoor environments with standard cultivation methods
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
31 Review of Literature
(Ventosa 2004) Saprophytic species of the genus Cladosporium are among the most
abundant fungi isolated in saltern samples Commonly isolated Cyanobacteria belong to
Nostoc and eukaryotic algae to Lyngbya and members of the Chlorophyceae such as
Chlorella Pseudococcomyxa and Pseudopleurococcus [Gorbushina et al (1987)
Calvo et al (1993) Arino et al (1996)]
They grow optimally on media with low water activity due to high salt or sugar
concentrations seem to propagate 70 vegetatively in the salterns and are thus
halotolerantosmotolerant species rather than simple flush-through occurrences
Cladiosporum herbarum was frequently isolated from hypersaline waters dead and dying
plant material air soil food fruit cereals paint and textiles (Ventosa 2004)
C) Algae
Most of the painted areas in temperature climate became covered with green algae
(Pleurococcus Protococcus and Trentopholia) while under tropical conditions blue green
algae of the genera Oscillatoria and Sytonema predominated (Garg 1995) The main
factors which contribute to the growth of algae on wall paintings are the presence of
moisture in the plaster as well as availability of visible light These conditions are quite
prevalent in the tropical climate but in temperature regions also algal growth on wall
paintings have been reported [Tonolo et al (1961) Pietrini et al (1991)]
D) Actinomycetes
Usually literature refers to specific aspects eg the occurrence of cyanobacteria
and algae in caves with natural openings to sunlight or those with artificial lighting fungi
and so forth Actinomycetes have been considered to be mainly confined to soils where
they find their natural habitat but despite intensive studies there are still many gaps in our
knowledge of the role played by actinomycetes in soil processes and biodegrations of
murals cave paintings (Groth et al 1999) In addition halophilic bacteria actinomycetes
and cyanobacteria are also capable of growing on salt-affected mural paintings
(Karbowska 2003)
Monte and Ferrari (1993) reviewed the mechanisms of biodeterioration in tombs
and underground churches The role of actinomycetes in the deterioration of frescoes in
hypogean environments was stressed by Agarossi et al (1985) Monte and Ferrari (1993)
Giacobini et al (1987) described the serious damage suffered by a whole series of famous
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
32 Review of Literature
frescoes in underground environments Actinomycetes were isolated from these mural
paintings located in crypts caves and tombs About 200 strains of actinomycetes were
isolated 60 of which were identified The most frequent species were Streptomyces albus
S cinereoruber S griseolus S vinaceus and some members of the Nocardia genus
Heterotrophic bacteria and actinomycetes were the most abundant microorganisms
on the frescoes of Etruscan tombs (Agarossi et al 1985) Bettini et al (1977) studied
some of the oldest Etruscan tombs (7th to 4th century BC) and found white-grey patinas
and spots from streptomycetes in the mural paintings They related the biodeterioration to
the microclimatic conditions (eg lower temperatures high RH) Monte and Ferrari (1993)
considered that colonization of the mural paintings was the result of selective competitive
and inhibitory dynamics among different microorganisms under different and changing
environmental conditions The pigments excreted by some actinomycetes were responsible
for the violet stains found on the walls of tombs in Tarquinia Similar stains were observed
in one of the Roman tombs the Circular Mausoleum the Necropolis of Carmona Spain
from which a Streptomyces sp producing violet pigments in culture media was isolated
214 Identification of biodeteriogens
The possibility of pigments and biodeteriogens identification in frescos and stone
monitoring is offered mostly by vibrational spectroscopy infrared thermography laser
induced fluorescence (LIF) laser induced breakdown spectroscopy (LIBS) XRF (X-Ray
Fluorescence) IR and UV emission Among them laser based methods allowing for in
situ or remote characterization of artwork surface were applied successfully for
prospecting diagnosis and maintenance (Colao et al 2005) The rep-PCR fingerprinting
of the isolates allowed determination of their genotypic diversity Studies that have
compared rep-PCR genomic fingerprint analysis with DNAndashDNA relatedness studies have
shown that the two techniques yield results that are in close agreement [Nick et al (1999)
Rademaker et al (2000)] These studies therefore suggest that rep-PCR fingerprinting can
be used as a genomic screening method to differentiate at the species level and to select
representatives for DNAndashDNA reassociation experiments (Heymann et al 2003)
The characterisation of bacteria was for example often limited to isolation from
group-specific media followed by microscopy [Sorlini et al (1987) Weirich (1989)
Tate et al (1990) and in more recent studies to morphological and physiological
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
33 Review of Literature
characteristics including miniaturised and automated systems such as API and BIOLOG
[Arroyo et al (1997) Jimmenez et al (2000) and Laiz et al (2000)] or to
chemotaxonomic characteristics [Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
Wagner et al (1994) demonstrated that conventional microbiological efforts can
fail to isolate all microorganisms present in natural samples DNA-based techniques used
to identify microorganisms have revealed only a smaller fraction of bacteria isolated from
artworks (Ward et al 1990 Rolleke et al 1996) Bacterial identification using molecular
techniques especially those including the sequencing of genes coding for ribosomal
16S rRNA is very important to study bacterial communities found on artefacts One such
method is Denaturing Gradient Gel Electrophoresis (DGGE) of PCR-amplified gene
fragments coding for rRNA (Muyzer et al 1993) that allows the separation of partial
16S rDNA amplified fragments of identical length but different sequence due to their
different melting behaviour in a gel system containing a gradient of denaturants
(Jimenez 2003)
Total genomic DNA was purified for 16S rRNA gene sequencing and rep-PCR
using a slight modification of the method of Pitcher et al (1989) as described by
Heyndrickx et al (1996) rep-PCR genomic fingerprinting was performed with the REP-
and (GTG)5 primers (Versalovic et al 1994) using the PCR conditions described
previously by Rademaker et al (1997) Electrophoresis and pattern analysis were further
performed as described by Heyrman et al (2003) 16S rRNA gene sequencing and
phylogenetic analysis were performed as described by Heyrman and Swings (2001)
Phylogenetic trees were constructed using the BioNumerics software (Applied Maths) by
applying the neighbour-joining and maximum-parsimony methods on a multiple alignment
similarity matrix The stability of relationships was assessed by a bootstrap analysis of
1000 datasets For determination of the G+C content and levels of DNAndashDNA
hybridization approximately 1 g biomass was harvested from agar plates DNA was
purified by using a combination of the protocols of Marmur (1961) and
Pitcher et al (1989) as described by Logan et al (2000) The G+C content of the DNA
was determined by HPLC (Mesbah et al 1989) using the further specifications given by
Logan et al (2000) DNAndashDNA hybridization experiments were performed using a
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
34 Review of Literature
modification of the microplate method of Ezaki et al (1989) as described by
Willems et al (2001)
215 Preservation and conservation
Nowadays the conservation and preservation of our cultural heritage is one of the
world main concerns particularly in Europe The increasing need for non-destructive
investigation tools has become a major issue as sampling is in most cases restricted in
view of the value or the uniqueness of the object Artworks as wall paintings in buildings
and monuments of historical interest are affected by environment physical (temperature
and humidity) and biological factors (biodeteriogens) and by human (pollutant releases)
impact and therefore modified over the time The term ldquoconservationrdquo may have many
different meanings in different fields Every intervention directed to the restoration and
safeguard of works of art is commonly considered as a conservation treatment For
example conservation can involve the cleaning procedures set up by chemists or the photo
documentation of the preservation of historical memory For the appropriate conservation
of works of art even the lighting systems in a museum or the control of the visitorrsquos
movements in a site should be monitored Chemical degradation which induces the flaking
of paintings and deterioration from rain wind dust and other environmental causes is
mainly responsible for the weakening of the porous structure and the surface layers of the
materials used in works of cultural heritage (Colao et al 2005)
216 Conservation history
Wall paintings are an integral part of monuments and sites and should be preserved
in situ Many of the problems affecting wall paintings are linked to the poor condition of
the building or structure its improper use lack of maintenance frequent repairs and
alterations Also frequent restorations unnecessary uncovering and use of inappropriate
methods and materials can result in irreparable damage Substandard and inadequate
practices and professional qualifications have led to unfortunate results It is for this reason
that an appropriate document covering the principles of proper conservation-restoration of
wall paintings is necessary
The Venice Charter (1964) has provided general principles for the conservation-
restoration of cultural heritage The Amsterdam Declaration (1975) introducing the
concept of integrated conservation and the Nara Document on Authenticity (1994) dealing
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
35 Review of Literature
with cultural diversity have expanded these principles Taking into account these and
additional relevant contributions such as the ICOM-CC Code of Ethics (1984) Document
of Pavia (1997) and ECCO Professional Guidelines (1997) the aim of this document is
to provide more specific principles for the protection preservation and the conservation
restoration of wall paintings This document therefore reflects basic and universally
applicable principles and practices and does not take into account particular problems of
regions or countries which can be supplemented at regional and national level by
providing further recommendations where necessary
217 Preservation techniques of the mural paintings
The removal of fat salts varnishes and pollutants from the surfaces of the works
of art are mostly done by chemical and mechanical methods At the end of the 19th
century the practices of restoration methods that do not inhibit further future interventions
was considered acceptable During the 1960s several chemicals such as polymeric resins
were synthesized and applied as a consolidation or protection agents The accepted idea
was that these substances could be removed at any time leaving a completely unaltered
substrate On the basis of origin archaeological objects can be classified as follows
(Carretti 2005)
1 Inorganic It includes siliceous and nonsiliceous materials Archaeological materials
produced from stones terracotta ceramics and glass can be included under siliceous
materials whereas objects made of metals can be included under nonsiliceous inorganic
materials Again metal objects can be classified as ferrous metals and non-ferrous metals
Objects made of iron are termed as ferrous metal objects whereas metal objects made from
other than iron is termed as non-ferrous metal objects
2 Organic It includes archival and anthropological materials Again archival materials
include paper bhojapatra tadapatra textiles wooden objects miniature paintings whereas
anthropological objects include bone and ivory leather feather and fur etc
In the past restoration of paintings and other old artwork often involved application
of acrylic resins to consolidate and protect them One of the most important tasks for
modern restorers is thus to remove these layers because it turns out that acrylic resins not
only by drastically changing the optics of the treated artwork but in many cases they
accelerate their degradation The scientists use an oil-in-water microemulsion with the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
36 Review of Literature
organic solvent para-xylene as the oil component The matrix makes the cleaning agent
viscous so that it cannot enter very far into the pores of a painting (Carretti 2005)
Nanoparticle treatment is the logical evolution of the Ferroni-Dini method
Dispersions of kinetically stable Ca (OH)2 nanoparticles in non-aqueous solvents solved
most of the drawbacks of the microsized powders Stable dispersions of calcium hydroxide
have been successfully applied (replacing polymers) as fixatives to re-adhere lifted paint
layers during many restoration workshops in Italy and in Europe as a consolidant The
FerronindashDini method (two steps the application of a saturated solution of ammonium
carbonate (NH4)2CO3 and the treatment with a barium hydroxide solution Ba(OH)2 also
called the barium method has long been the acknowledged method for the removal of
salts that threaten paintings reinforcing at the same time the porous structure However
commercially available carbonates and hydroxide powders have dimensions of several
micrometres much larger than the pores on the paint surface This means they donrsquot
penetrate the painting well and there is also a risk of damaging the artwork by a white
glaze forming on the surface (Berger 2006) Restoration should provide the reinforcement
of the porous structure and the consolidation of the surface layer of arte facts A few
simple principles can be considered to define the most appropriate restoration method
1) The treatment should be reversible so that one can revert to the original status of the
work of art at any desired time
2) All the applied chemicals must ensure the maximum durability and the chemical
inertness
3) The applied chemicals must invert the degradation processes without altering the
chemical composition of the artefacts and their physico-chemical and mechanical
properties (Baglioni 2006)
218 Commercial preservative used for preservation of mural paintings
Cleaning was done using soft brushes vacuum cleaner and Gumma paine (dough)
a natural latex sponge Areas near the window were very dirty with black soot and were
cleaned with micro fibrous cloths moistened with synperonic N (surfactant alkyl phenol
ethoxylate based on nonyl phenol) and neutralized with clean water In several places the
paint layers had separated from the substrate (exfoli-ation) In that cases loose paint flakes
were stuck back using Paraloid B72 (10 solution in ethanol) as sparingly as possible
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
37 Review of Literature
Paraloid was injected with syringe behind the exfoliated area twice pushed and held back
with Melinex (polyester film) until fixed on the third application (Bionda et al 2002)
In a period of significant growth of molds and intensive efforts to stop the mold
contamination some of the lines of certain paintings were obscured or faded Solutions of
ethanol formalin 91 and Thiabendazole (TBZ) were used but they were not very
effective Para-formaldehyde fumigation was adopted beginning in 1981 to establish an
emergency treatment sensitivity of microorganisms from studied samples was tested
against Desogen by adding 1-3 (v v) in serial dilutions The best concentration
3 (vv) was applied with a brush to prevent spreading of the spores In order to overcome
the problem of fungal attack suitable fungicides carbendizeme or kiroxy-I or 5 solute of
N formaldehyde can be used Shellac solution in spirit or 2 solution of polyvinaycletate
in toluene can be used as preservative and consolidantsTo control insect and fungal attack
fumigants like pyrethrum DDT or 5 solution of sodium penta chlorophenate in kerosene
oil 2 to 5 solution of PVA in toluene or 2 to 5 solution of paraloid B-72 in toluene or
acetone be used (Miura 2009) Microclimatic conditions constitute a critical factor in the
conservation of cave paintings The unstable microclimatic condition is one of the factors
that always affect the state of conservation of mural paintings In the environmental-
monument system knowledge of the functional environment and climatic conditions of the
surroundings are necessary for the identification of causes of decay (Singh 2011)
Furthermore the risk of formation of indoor bioaerosols in residential and public
buildings (offices schools museums etc) has attracted interest in the last years due to
socio-economic as well as sanitary reasons (Ripka 2005) Thus it is important in aspects of
health and maintenance of Cultural Heritage to analyse the complete microflora to further
develop biocides for harmful microorganisms and methods for restoration of damaged
objects of art The biocidal testing was carried out on one representative algal species of
the two classes of algae viz Chlorococcum sp (green) and Chroococcus sp (blue-green)
found to be common in all the samples Efficiency tests were carried out both in liquid as
well as solid media containing algal suspensions by adding a biocide solution of known
concentration and determining the growth of the microorganism after the incubation
period The biocides used for the past studies were
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
13 Review of Literature
The most important sites of rock paintings in North India are at Bimbetka Gwalior
Tikla Ayra Bhanpura Rampura Singhauli Bhojpur Adamgrh Delware and Mirzapur
In South India they are found at Mehaboob Nagar (Andhrapradesh) Edakkal Marayoor
Perimkadavila (Kerala) Mallampadi (Tamilnadu) and Bellary (Karnataka)These
paintings were considered as the early models of mural paintingsThe mural painting of
Sittannavasal Badami Lepakshi Tanjore Vijayanagar and Kerala has a lot of similarities
(Sasibhoosan 1987)
25 South Indian murals
South India also got rich tradition of mural paintings In the reign of Cholas
Vijayanagaras and Nayakas this art reached the climax The Deccan art of Bijapur
Hyderabad and Golconda schools were influenced by the Mughal traditions and later by
European idiom Maratha murals are also shaped under the Mughal traditions and
employed oil as medium The Mural art of Kerala vividly depicted on the walls of temples
and monuments show the traces of European affinity In Tamil Nadu almost all the extent
examples of frescos have been done on rock surfaces and stone walls This is a crucial
factor in determining the quality of frescos (Havell 1982) The ceiling of the Virupaksha
temple in Hampi is covered with paintings of the 15th century The paintings on the ceiling
of the mandapa of Lepakshi temple are some of the finest mural paintings of the medieval
period in India Legends associated with Siva and Parvati Krishna and Rama were painted
on the walls of palaces and temples in Kerala from the 16th to 19th century Mural
paintings were made on the walls of all the palaces within the magnificent Orccha fort The
Raj Mahal was completely adorned with mural paintings of the 17th century
Figure-27 Virupaksha temple in Hampi
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
14 Review of Literature
Figure-28 Ceilings of Virupaksha temple Hampi
The murals on the walls of the navaranga (the central pillared hall) depict stories
from Bhagavatha and are excellent examples of 19th
century Mysore paintings The
Mallikarjunaswamy temple on the hill is one of the Panchalingas of Talakad and the
temple has a beautiful mural painting on the wall of the temple The Dariya Daulat Bagh
has excellent mural painting (Sasibhoosan 1987)
Figure-29 Paintings on the walls of Jagan mohan palace Mysore
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
15 Review of Literature
Figure-210 Painting of Raja woodeyar era
Kerala mural paintings are the frescos depicting mythology and legends which are
drawn on the walls of temples and churches in South India principally in Kerala Ancient
temples churches and palaces in Kerala South India display an abounding tradition of
mural paintings mostly dating back between the 9th to 12th centuries The murals of
Thirunadhikkara Cave Temple (now ceded to Tamilnadu) and Tiruvanchikulam are
considered the oldest relics of Keralarsquos own style of murals Fine mural paintings are
depicted in temples at Trikodithanam Ettumanur Vaikom Pundarikapuram
Udayanapuram Triprangode Guruvayoor Kumaranalloor Aymanam the Vadakkunathan
temple in Trichur and the Sri Padmanabhaswamy temple at Thiruvananthapuram Other
mural sites are in the churches at Edappally Vechur Cheppad and Mulanthuruthy and at
palaces such as the Krishnapuram Palace near Kayamkulam and the Padmanabhapuram
Palace
Figure-211 Kerala murals
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
16 Review of Literature
Figure-212 Murals paintings of Kerala temples
There are wall paintings in Badami in the Bijapur district Karnataka Some
excellent paintings exist in the Jain caves at Sitanavassal in Puddukkottai District of Tamil
Nadu Tamil Nadu gave exuberant and glorious expression to themes relating to Siva in the
temples of Panamalai and Kailashanatar in Kancheepuram In the 9th century Jain cave of
Sittannavasal in Tamil Nadu there is a marvellous lotus pond painted on the ceiling In
the heart of the Brihadeeswara temple in Thanjavur Tamil Nadu protected by massive
walls of stone are the finest paintings of the theme of Siva ever painted towards the end of
the 10th century (Sivaramamurthi 1992)
Figure-213 Kancheepuram Mural paintings
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
17 Review of Literature
Figure-214 Sculpture of Mahabalipuram
26 Methods of mural painting
In the history of mural several methods have been used The Buon fresco technique
consists of painting in pigment mixed with water on a thin layer of wet fresh lime mortar
or plaster The pigment is then absorbed by the wet plaster after a number of hours the
plaster dries and reacts with the air it is this chemical reaction which fixes the pigment
particles in the plaster After this the painting stays for a long time up to centuries in fresh
and brilliant colors A Secco painting is done on dry plaster The pigments thus require a
binding medium such as egg (tempera) glue or oil to attach the pigment to the wall
Mezzo-fresco is painted on nearly-dry plaster which is defined by the sixteenth-century
author Ignazio Pozzo as ldquofirm enough not to take a thumb-printrdquo so that the pigment only
penetrates slightly into the plaster Ancestral Hopi village archaeologists found that
fourteen kivas had painted murals and multiple layers of murals on the walls some with up
to twenty-seven layers of murals (Saturno 2006)
The colors used in painting are generally obtained from plants and minerals
Among them only such colors which are lime resistant are suitable for mural painting The
selection of proper colors for a mural painting is an important part of the work as the
longevity the painting depends on it Only mineral colors are preserved for a long time
which could be the reason for use of those colors in early days As per ldquoShilpa ratnardquo and
ldquoAgnipuranardquo the colors used in mural painting are white black red yellow blue and
green Yellow and red are from yellow ochre and red ochre Blue is generally indigo or
china blue White is the prepared wall and black is the carbon soot Mural paintings have
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
18 Review of Literature
survived centuries only on account of the identification and use of those colors which does
not have any reaction with lime (Miraseth 2006)
Originally three types of brushes were made and used flat medium and fine Flat
brushes were made from hairs behind calfrsquos ear the medium from the bottom of goats
belly and the fine brush from delicate blades of grass However in due course of time and
change use of easily available brushes from commercial market and shading of the
original colours can be distinctively noticed The use of blue colour is also noticed over the
passage of time The paintings have been brought down from the walls to plywood cloth
paper and other frames for easy to make and use purposes (Chakarabarti 1980)
27 Themes of mural painting
The subjects and themes in the murals are centered on the Hindu pantheon of Gods
and Goddesses drawn from description in the invocatory verses or Dhyana Slokas More
common representations are of Vishnu in different incarnations Ganesha and
manifestations of Siva We see murals in the Pallimanna Siva Temple devoted to Siva-
Parvatirsquos marriage the Ramayana Story being narrated on the walls of the Mattancheri
palace in the Sankara Narayana the Mahabharata is retold Murals are various scenes from
the Hindu epics and also the frolics of Lord Krishna
It would be interesting to bring into account the influence of the mural paintings on
Christianity On various churches like the St Georgersquos Orthodox Church has Christian
murals bringing out biblical characters and narrating stories from the scriptures Mar
Sabore and Afroth Church at Akapparambu in the outskirts of Ernakulam also have murals
of scenes from the bible Interestingly StMaryrsquos Church at Kanjoor has on both sides of its
entrance a battle scene between the armies of Tipu Sultan and of the English East India
Company It is also apparent that the history of Kerala Murals has its origin in the temple
walls and thus a study of Kerala Murals is not complete without pondering on the
architecture of Kerala its association with the murals (Warrier 2011)
28 Technique used in mural paintings
Indian murals executed on walls of caves structural temples walls of palaces were
based on highly developed techniques Mural painting is a composite structure of these
three basic layers the support the ground and the pigment layer In case of wall painting
the wall itself is the support This is followed by the layer or layers of plaster which
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
19 Review of Literature
constitute the ground The pigment layer is the one which contains the picture The support
is the wall which may be rock surface in a cave or a structural one These stone surfaces
which serve as carriers are rough or uneven This unevenness is itself an advantage as it
provides ldquotoothrdquo to hold the plaster on the surface The uneven surface of the wall has to be
made uniform with layers of plaster in successive gradation of fineness There is generally
one layer of rough plaster followed by one or more layers of fine plaster Ground or plaster
is a term used to mean the surface material of a wall or building which is applied as a
plastic mass made by mixing certain materials with water letting the mass set by drying
carbonation or hydration The active or setting components of plaster are commonly clay
which sets by drying lime which sets by carbonation gypsum and pozzolana which sets by
hydration (Mini 2010)
There are different mixtures for rough plaster In all the mixtures clay limestone
lime and shells in powdered form serve as the matrix The particles of which are held
together by the organic materials like gum glue extracts from barks etc are in fact
adhesives The fine plaster layer requires more careful preparation because it is the layer on
which the pigments are laid to make the picture ldquoShilparatnardquo suggest a mixture of conch
Oyster shells or white clay with gum of neem or slaked lime and coconut water Here the
consolidation is effected by the carbonation of slaked lime ie it absorbs carbon dioxide
from air and becomes carbonate Mural paintings were lime-washed from the 17th until the
beginning of 19th century A few paintings in vaults were never lime-washed for example
at Taby and Floda painted by the medieval painter Albertus Pictor (Mini 2010)
All the paintings have certain basic common characteristics There has to be a wall
or rock surface called support over which the artist goes to work A plaster base called
ground of varied thickness is laid on the support The ground may consist of one or more
layers The strength and life of the whole mural depended up on this ground over which the
painting was done It is the process of applying the final painting on the ground determines
the character of the mural whether it is fresco or tempera The mural painting is done
usually by creating wall surface free of any previous oil or paint by using solvent or by
sand blasting The brick wall is first plastered with mixture of lime and sand in the ratio of
12 A mixture of egg yolk vinegar oil colour is used in dry plaster
There are at least six stages before a Kerala Mural Painting is complete Lekhya
Karma is the first stage where sketching by pencil or crayon is done The second stage is
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
20 Review of Literature
the Rekha Karma which enhances the outlines of the sketching done The third stage called
Varna Karma breathes life into the painting with its colours Here all colours are
appropriately filled in The colouring of the human figures is done according to the
characters and their common virtues The divine and noble characters (Saatvik) are painted
in green those inclined towards power and wealth (Raajasik) is painted in shades of red
lowly mean characters (Tamasik) in white and demons in black In the fourth stage or the
Vartana Karma shading is done Fifth stage called the Lekha Karma brings us to the final
outline of the painting which is usually in black The final and the finishing touches stage
are called Devika Karma (Warrier 2011)
29 Dyes used in mural painting
Indians have been considered as fore runners in the art of natural dyeing Natural
dyes find use in the colouring of textiles drugs cosmetics etc Owing to their non-toxic
effects they are also used for colouring various food products In India there are more
than 450 plants that can yield dyes In addition to their dye-yielding characteristics some
of these plants also possess medicinal value Though there is a large plant resource base
little has been exploited so far Due to lack of availability of precise technical knowledge
on the extracting and dyeing technique it has not commercially succeeded like the
synthetic dyes (Siva 2007)
The color materials on the mural paintings in ancient India were derived from the
natural materials like terracotta chalk red ochre and yellow ochre mixed with animal fat
The dyes for painting is prepared such as white from lime Black from carbon soot of
lamps Red and yellow from minerals Blue from indigo ferra Deep red from lac A fine
coating of resin is done after the painting in order to make a shining appearance Egg yolk
and vinegar was mixed with oil colors and painted on dry plaster (Krishnakumar 1999)
Although plants exhibit a wide range of colours not all of these pigments can be
used as dyes Some do not dissolve in water some cannot be adsorbed onto fibres whereas
others fade when washed or exposed to air or sunlight It remains a mystery why plants
reward us with vibrant dyes India has a rich biodiversity and it is not only one of the
worldrsquos twelve mega diversity countries but also one of the eight major centres of origin
and diversification of domesticated taxa It has approximately 490000 plant species of
which about 17500 are angiosperms more than 400 are domesticated crop species and
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
21 Review of Literature
almost an equal number their wild relatives Thus India harbours a wealth of useful
germplasm resources and there is no doubt that the plant kingdom is a treasure-house of
diverse natural products One such product from nature is the dye (Siva 2007)
Many natural dyestuff and stains were obtained mainly from plants and dominated
as sources of natural dyes producing different colours like red yellow blue black brown
and a combination of these Almost all parts of the plants like root bark leaf fruit wood
seed flower etc produce dyes It is interesting to note that over 2000 pigments are
synthesized by various parts of plants of which only about 150 have been commercially
exploited Nearly 450 taxa are known to yield dyes in India alone of which 50 are
considered to be the most important ten of these are from roots four from barks five from
leaves seven from flowers seven from fruits three from seeds eight from wood and three
from gums and resins Some important dye-yielding plant habitats their distribution and
colouring pigment (Siva 2007)
The dye is generally prepared by boiling the crushed powder with water but
sometimes it is left to steep in cold water The solution then obtained is used generally to
dye coarse cotton fabrics Alum is generally used as a mordant Flowers of Butea
monosperma (Lam) Taubert yield an orange-coloured dye which is not fast and is easily
washed away For the purpose of colouring the material is steeped in a hot or cold
decoction of the flowers A more permanent colour is produced either by first preparing the
cloth with alum and wood ash or by adding these substances to the dye-bath The dye
indigo is produced by steeping the plant in water and allowing it to ferment This is
followed by oxidation of the solution with air in a separate vessel Mallotus philippinensis
muell yields an orange colour used for dyeing silk and wool To prepare the annatto dye
from B orellena the fruits are collected when nearly ripe The seeds and pulp are removed
from the mature fruit and macerated with water Thereafter they are either ground up into
an lsquoannatto pastersquo or dried and marketed as annatto seeds Sometimes when the seeds and
pulp are macerated with water the product is stained through a sieve and the colouring
matter which settles out is collected and partially evaporated by heat and finally dried in
the sun (Sowbhagya 2002)
The predominant colors used in rock art and cave art are black (from charcoal soot
or manganese oxide) yellow ochre (limonite) red ochre (hematite or baked limonite) and
white (kaolin clay burnt shells powdered gypsum or powdered calcium carbonate) All of
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
22 Review of Literature
theses pigments may be used on leather or raw hide as well Early cave art in Seminole
Canyon was monochromatic in red and as culture grew more sophisticated the color
palette expanded Blue Orange Brown Green and Purple are the most common colours
used in Ajantha murals White Pink Gold are occasionally represented mineral earths
containing ferric oxide and copper carbonates were used as source of red yellow and green
colours There is also evidence to establish that root of Rubia cardifolia and leaves of
Indigofera tinctoria were used as source for red and blue colours (Nayer et al 1999)
Many colors of pigments were obtained from both organic and inorganic sources in
ancient times and used to paint various surfaces such as braintan leather clothing and
accoutrements rawhide the human body etc Blue color was obtained from powdered
azurite and lapis duck manure and certain clays Fine Blue-green clay was obtained from
deposits near Mankato Michigan Organic sources of blue include Turkeys Tail a
greenish blue polypore that grows on dead decaying wood (not tannish ones) Native
Americans get Indigo from either Guatemala or Ecuador which was traded well up onto
Kansas long before the Spanish ever set foot here American Indigo has purple tones to it
but IndianJapanese indigo has green tones Berries and crushed flowers were also used to
obtain blue color by rubbing the plant material directly on the leather
An organic source of red was Cochineal It was native west of the Mississippi and
is produced from the bodies of small insects that grow on the prickly pear cactus Ladys
Bedstraw gives a good vermillion red color Harvest the roots dry them out clean the mud
etc off of them and then grind the roots really fine then soak them to extract the red
coloring The key here is drying the root first Blood was also used as red pigment Pucoon
roots also yield a red pigment (Smith 2002) Red ochre the reverse original red colours are
due to variations in iron oxide (or) calcite content and to redox conditions in the firing
produced Brown coloured ceramics owe their colour to maghemite and must be
considered as a fabrication defect due to the position of the ceramic piece in a zone where a
reducing atmosphere prevailed in the course of firingRed pigments were produced from
iron oxides like hematite or limonite and from ochre Hematite was the most frequently
used mineral It occurs in the form of aggregates of small red crystals or in the form of
bigger black crystals which are difficult to crush white was obtained mostly from
kaolinite or illite (Clottes et al 1990)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
23 Review of Literature
210 Biodetoriation of mural paintings
Historic items often contain natural biodegradable materials and have histories of
exposure to moist conditions These two conditions make them amenable to microbial
attack Microbial colonization may damage the building or the cultural asset
(Salonen 2001) Biodeteriogens are organisms involved in deterioration of artifacts They
are very specific for each type of artifact in accordance with its chemical structure and
environment They also have different nutritional requirements and act directly or
indirectly on the substrate The adhesion of microorganisms to a substrate is the result of
cell hydrophobicity and of excreted polymeric substances contained by sheaths capsules
and slimes (Colao 2005)
The surviving wall paintings and decorations in subterranean environments around
Malta are rather scarce (Buhagiar 1986 1993 1998) These include those at St Paulrsquos
Catacombs (Zammit 2008) St Agatharsquos Crypt and Catacombs (Camilleri 2001)
San Catald Catacombs Tac-Cghaqi Abbatija tad-Dejr (Buhagiar 1993) all in Rabat the
cave-sanctuary in Mellieħa (Buhagiar 1987) and the Ħal Saflieni Hypogeum in Paola
(Pace 2000) Previous studies conducted on wall paintings and decorations in Maltese
Palaeo-Christian Catacombs have involved their manufacturing techniques (Muscat 2005)
However to date limited systematic studies have been conducted into the biodeterioration
in Maltese Palaeo- Christian Catacombs The only such studies ever conducted in Malta
concerned the biodeterioration of works of art in catacombs have been carried out at St
Agatharsquos Crypt and Catacombs in Rabat (Zammit et al 2008 Psaila 2006)
Microorganisms can be responsible for the destruction of monuments buildings
and cultural heritage assets including the decay of concrete cement stones mural
paintings etc These microorganisms are not only related with biodeterioration but water-
damaged indoor building materials are frequently colonized by complex bacterial
communities and may emit mixed bioaerosols into the indoor air (Jimenez 2000) It is
well known that mural paintings are colonized by micro-organisms and can be severely
damaged by such growths (Ciferri 1999) A large number of fungal (gt50) and bacterial
taxa (70) have been detected in indoor environments Over 50 bacterial species and 14
genera novel to science were reported in the past 10 years from indoor air and historic
items indicating bacterigravea in these enviroments are as yet only fragmentarily known
(Salonen 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
24 Review of Literature
Traditionally the study of microflora which causes this biodeterioration was based
on classical cultivation methods that were mainly useful to study the physiological
potential of microorganisms but do not provide information on all microbial communities
to be found in excavated artifacts Indeed many studies using culture-independent
techniques which cultivate microorganisms from different environments may often
represent only minor components of the microbial community as a whole It is generally
accepted that cultivation methods recover less than 1 of the total microorganisms present
in environmental samples (Ward et al 1990 Amann et al 1995) Hence microbial
investigations based only on cultivation strategies cannot be regarded as reliable in terms
of reflecting the microbial diversity present in objects of art (Osburn et al 2011)
Early workers suggested that the presence of living microorganisms on stone
increased its susceptibility to damage through their water-binding capacity It has recently
been reported that the mineralogy porosity surface roughness and capacity to collect
water and organic materials control its bioreceptivity and tendency to biodeterioration
(Diakumaku 1995) In addition environmental factors as temperature light pH and
relative humidity affect the number and type of colonising species (Tiano et al 1995) and
hence the progress of colonisation Biofilms on decayed stones consist on mixed microbial
populations embedded in a polymeric matrix Fungi algae filamentous and unicellular
bacteria are found in these complex communities A variety of bacteria have been isolated
from different stone samples confirming the dominance of Gram-positive organisms
especially spore-forming bacteria such as Bacillus and filamentous actinomycetes
(Ripka 2005)
In cultivation studies of deteriorated mural and rock paintings bacterial isolates
have frequently been attributed to the genus Bacillus (Weirich 1989 Tate and Rebrikova
1991 Gonzalez et al 1999 Heyrman et al 1999 Jimenez et al 2000) Other studies that
have included DNA-based techniques to characterize the bacterial community involved in
biodeterioration have shown that a substantial part of the bacterial population is made up of
so far unknown species (Altenburger et al 1996 Rolleke et al 1996 Gurtner et al 2000
Heyrman and Swings 2001) (Heymann et al 2003)
Many potential mycotoxin producers have been detected in air and items from
indoor environments with histories of exposure to moisture for example species of
Acremonium Alternaria Aspergillus Chateomium Fusarium Eurotium Paecilomyces
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
25 Review of Literature
Penicillium Scopulariopsis Stachybotrys Trichoderma Verticillium and Wallemia
(Peltola et al 2001 Pieckova et al 2001) Not all strains of one species produce
mycotoxins and different strains may produce different toxins Whereas toxin producing
strains are frequent in crops and outdoor vegetation toxin producing isolates from indoor
environments and non living assets have only been reported of the species Aspergillus
versicolor (Nielsen et al 1998) Stachybotrys chartarum Nikulin (1997) and
Trichoderma harzianum (Peltola et al 2001) Streptomyces griseus strains producing
valinomycin occur in environments where humans can get exposed
(Andersson et al 2002) The biological properties and toxicity mechanisms of cereulide
were identical to those by valinomycin (Mikkola et al 1999 Salonen et al 2001)
The genus Paenibacillus was first proposed by Ash et al (1993) and its description
was emended by Shida et al (1997) The genus Paenibacillus is under intensive taxonomic
investigation with ten species having been formally described in the last year Heyrman amp
Swings (2001) isolated a strain originally classified as Paenibacillus sp LMG 19508
from biodeteriorated mural paintings in the Servilia tomb at the Roman necropolis of
Carmona in Seville Spain (Smerda et al 2006) Building stone and wall paintings contain
a variety of hydroscopic salts including carbonates chlorides nitrates sulfates etc
dispersed within the porous material or locally concentrated These salts are solubilised
and migrate with the water in and out of the stone Due to changes in physical parameters
the so called salt efflorescences appear on the surfaces providing extremely saline
environments and building niches for settlement of halophilic microorganisms Halite and
other hygroscopic salts can retain considerable quantities of moisture when entrapped in
the building materials and thus favouring the bacterial growth (Ripka 2005)
It is demonstrated that water-damaged indoor building materials contained
substances of microbial origin extremely toxic to eukaryotic cells and large quantities of
several microbial species known to be potentially toxic or immunopotentiating These
include peptidoglycans Gram-negative endotoxin β-13-D glucans lipoglycans and
teichoic acids and mycotoxins (Jimenez 2000) In turn these microorganisms can mediate
the crystallization process These crystallizations can produce destructive effects Some
salts may crystallize or recrystallize to different hydrates which occupy a larger space and
exert additional pressure producing cracking powdering and flaking
(Jimenez and Laiz 2000)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
26 Review of Literature
211 Types of deterioration on mural paintings
The frescos represent a variety of ecological niches where primary colonization is
due to photoautotrophic and chemolithoautotrophic microorganisms followed by
secondary colonization due to heterotrophic bacteria that obtain nutrients from various
sources (metabolites of autotrophic bacteria airborne organic contamination animal faeces
and organic compounds in the paint layers themselves) Microbial-induced deterioration
processes cause structural as well as aesthetic damage to wall paintings such as the
discoloration of materials the formation of crusts on surfaces and the loss of material
(Sarro et al 2006 Osburn et al 2011) Halophilic bacteria and archaea were thought to
be found only in extreme environments like salt lakes or black smokers However it has
been shown that mural paintings and stones are a common habitat for extremely salt
tolerant and moderate halophilic (Ripka 2005) Microbial induced deterioration processes
can cause different kinds of alterations such as discolouration of materials the formation of
crusts on surfaces and the loss of material which leads to structural damage (Ripka 2005)
First of all microorganisms can cause severe problems due to the excretion of aggressive
metabolic products such as organic or inorganic acids Secondly material components can
be used as substrates for microbial metabolism Exoenzymes such as cellulases proteases
tannases beta-glucosidase produced by fungi and bacteria are responsible for hydrolysis of
cellulose and proteins Further examples are mechanical processes caused by swelling and
shrinking of slime or mycelia penetrating inside plaster of the painting resulting in loss of
cohesion and detachment of the paint layer (Rolleke 1996 Gurtner et al 2000)
Table-21 Microbial damage on mural paintings (Rolleke 1996)
S No Damage Microbial activity
1 Green brown red grey
surface layers (patinas)
Pigments produced by microorganisms (intra-or
extracellular) as chlorophyll and carotinoids
2 Dislodging of painting layers Use of organic binders as nutrient and energy
source
3 Acid attack of carbonates Acid produced by fungi or bacteria
4 Discolouration of pigments Redox-reactions induced by fungi and
bacteria
5 Loss of paint layer Growth of microorganisms deep into the plaster
6 Hydrolysis of synthetic
polymers Chemoorganotrophic activity of bacteria and fungi
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
27 Review of Literature
Discolorations are caused by excretion of pigments and microbiologically induced
reductionoxidation-processes (Krumbein et al 1990) Degradation of the bindings is
followed by reduction of stability Oxidation of ammonium and reduced sulphur
compounds results in acidification of the environment such as Sulphuric acid and the
variety of organic acids produced by the heterotrophs cause solubilization of calcareous
binding material and chelation of metal ions (Bock et al 1993) It is now well recognised
that wall paintings can be deteriorated by microorganisms (Ciferri 1999)The growth of
microorganisms essentially results in two types of damage aesthetic and structural
Aesthetic damage implies pigment discoloration stains and formation of a biofilm on the
painted surface Structural damage is observed as cracking and disintegration of the paint
layer formation of paint blisters and degradation of support polymers or of glues and
binders resulting in detachment of paint layer from the support The colonization of mural
paintings by bacteria and other microorganisms can have different causes Provided that
favorable environmental conditions occur nutrients for heterotrophic bacteria and fungi
can be available from metabolites of autotrophic bacteria from airborne contamination and
dripping water from animal faeces but also from organic compounds in the paint layer
itself
212 Methods of studying biodeterioration
It is now well recognized that wall paintings may be deteriorated by
microorganisms as established by several studies that linked the observed damage with the
microbial community present as reviewed by Ciferri (1999) Despite this knowledge a
reliable characterization of bacteria associated with such damage is often lacking To
obtain greater insight into the bacterial community involved in biodeterioration of mural
paintings three sites (from the necropolis at Carmona Spain and the Saint-Catherine
chapel of the castle at Herberstein Austria) were sampled In previous studies from these
sites 385 isolates were analysed by fatty acid methyl ester GC and representatives of
different fatty acid clusters were further studied by 16S rRNA gene sequencing
(Heyrman and Swings 2001) Several of these representative strains showed the highest
sequence similarity with members of the genus Arthrobacter (Heyrman et al 2005)
Jimenez and Samson (1981) analysed the microbial flora of a large fresco painted
in the late 1920s in the monastery ldquoSanta Maria de la Rabidardquo (Huelva Spain) exhibiting
two types of deterioration white efflorescence and green-to-black stains
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
28 Review of Literature
Tate and Rebrikova (1990) thought autotrophic nitrifying bacteria to be the first colonisers
of damaged frescoes and building materials in the cathedral of the nativity of the Virgin in
the Pafnutii-Borovskii monastery (Russia) The bulk of research on biodeterioration of
mural paintings has focused on explaining the observed phenomena by analysing the
microflora present Following this approach a precise characterisation of the
microorganisms using a polyphasic approach was never the first goal
Only a few studies included genomic fingerprinting (16S rDNA sequence analysis)
for the characterisation of bacteria associated with damage on mural paintings
[Rolleke (1996) Pinar et al (2001)] Previous studies based on culture-dependent
techniques showed that the flora present on frescos are fungi (predominant species of
Penicillium Aspergillus Cladosporium and Engyodontium) (Guglielminetti et al 1994)
bacteria (predominant species of Bacillus Arthrobacter Micrococcus Streptomyces and
Pseudomonas) (Heyrman et al 1999) cyanobacteria and eukaryotic algae (species of
Nostoc Lyngbya and Chlorophyceae) (Arino et al 1996 Calvo et al 1993) The killing
effect of an antimicrobial agent on a microorganism can be assessed in several ways
(1) Lethal activity may be expressed as the rate of killing by a fixed concentration
of drug under controlled conditions This rate is determined by measuring the number of
viable bacteria at various time intervals The resulting graphic depiction is known as the
time-kill curve Bacterial killing rates are in part dependent on the class of antibiotic and
the concentration of this agent With certain classes of antibiotics (eg aminoglycosides
and fluoroquino-lones) the rate of killing increases with increased drug concentrations up
to a point of maximum effect This is termed concentration-dependent bactericidal activity
In contrast the killing rates of szlig-lactam agents and vancomycin are relatively slow and
continue only as long as the concentrations are in excess of the MIC This rate of killing is
termed time-dependent bactericidal activity
(2) The minimal concentration of drug needed to kill most of the viable organisms
after incubation for a fixed length of time (generally 24 hours) under a given set of
conditions is the most common estimation of bactericidal activity and is known as either
the minimal bactericidal concentration (MBC) or the minimal lethal concentration (MLC)
It will be referred to in this document as the MBC Unfortunately the definition of the
MBC (999 killing of the final inoculum) is somewhat arbitrary and separates the
bacteria into two populations ndash a segrega-tion which might not have biological relevance
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
29 Review of Literature
The determination of the MBC moreover is so subject to methodologic variables that the
clinical relevance of MBCs is nearly impossible to assess particularly for certain pathogen
and drug combinations (eg Staphylococci and beta-lactam agents)
(3) The serum of a patient receiving an antibiotic may be tested against the
infecting microorganism This can be done using time-kill curve methodology (ie serum
bactericidal rate) or using dilution methodology (ie serum bactericidal titer) The
principles of these methods as well as the influence of biological and technical factors are
similar (Barry et al 1999)
213 Microbial flora associated with deteriorated mural paintings
A great deal of research has been done in this field mainly by using cultivation dependent
methods However by using culture-dependent methods only a very small proportion of
microorganisms can be obtained Far less than 1 of organisms in the environment can be
cultivated by standard cultivation techniques (Pace 1996) Recent studies have shown that
culture-dependent techniques yielded mainly sporeforming bacteria suggesting that plating
leads to an over estimation of the number of spore-forming bacteria A wide number of
investigations have shown that in addition to chemical and physical processes
microorganisms play a major role in degradation of objects of art such as paintings stone-
works wood paper masonry leather parchment glass and metal (Ripka 2005)
A) Bacteria
In general growth of diverse organisms on mural paintings is supported by
humidity slight alkaline pH values and the presence of organic and inorganic nutrient
sources (Weirich 1989) In mural paintings pigments are suspended in water or oil often
binders such as casein and milk are used and they are supplied on the damp lime plaster
(Ciferri 1999) The calcium carbonate formed on contact with air consolidates the
pigments Thus frescos contain mainly inorganic components While chemoautotrophic
nitrifiers and thiobacilli obtain their energy for growth by oxidizing ammonium and
reducing sulphur-compounds respectively heterotrophic bacteria and fungi depend on
organically bound carbon [Tate et al (1991) Lazar (1971) Petushkova et al (1986)
Jimenez et al (1981)] Thus primary colonization of photoautotrophic Cyanobacteria
chemolithoautotrophic nitrifying bacteria and sulphuric acid producing thiobacilli represent
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
30 Review of Literature
the first supply of organic matter The death and lysis of such bacteria promotes the
secondary settlement of heterotrophic bacteria and fungal populations (Calvo et al 1991)
Bacteria may derive from plants or pollen as many sequences obtained in this study
gave high score similarities with bacteria isolated from plants like Moraxella osloensis
Enterobacter cloace Enterobacter agglomerans and Pantoea endophytica Bacteria may
also derive from animal faeces like flies Bacillus Pseudomonas Aeromonas and Panteoa
(Ripka 2005) As Lazar and Dumitru (1973) reported studying mural paintings in a
Romanian monastery the genera Bacillus Arthrobacter and Pseudomonas have been
proved to produce salt efflorescences and were even considered to cause the blanching
phenomenon of frescoes (Jimenez et al 2000) Predominant bacterial genera are Bacillus
Streptomyces Arthrobacter Micrococcus and Pseudomonas [Weirich (1989)
Tate et al (1990) Arroyo et al (1997) Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
B) Fungi
It may be concluded that there is wide variety of fungal forms present on mural
paintings but Aspergillus and Alternaria were found dominating from all the experimental
sites next to them were Cladosporium Drechestera Fusarium Curvularia Chaetomium
Memnoniella Mycelia sterelai Pencillium Emericella Stachybotrytis Trichoderma
Phoma Monodictys Humicola and Epicoccum (Garg et al 1995)
The fungal genera most commonly found in lists of isolated taxa given in literature
are Alternaria Aspergillus Chaetomium Cladosporium Fusarium Penicillium and
Verticullum [Weirich (1989) Tate et al (1990) Guglielminetti et al (1994)
Garg et al (1995) Berner et al (1997) Ciferri (1999)] Some fungi having hard fruiting
bodies represented by sclerotia pycnidia perithecia cleistothecia and stroma could
organize themselves inside the painted layer Many fungal forms having such structures
were identified from our experimental sites viz Emericella nidulans A flavus
Chaetomium sp and Phoma sp etc These structures with little increase in humidity may
cause swelling in the paint film (Garg 1995)
Strains of species of Alternaria and Cladosporium both of them identified on the
mural paintings of the Palace of Schoumlnbrunn are the most common genera isolated from
stone and mural paintings in indoor environments with standard cultivation methods
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
31 Review of Literature
(Ventosa 2004) Saprophytic species of the genus Cladosporium are among the most
abundant fungi isolated in saltern samples Commonly isolated Cyanobacteria belong to
Nostoc and eukaryotic algae to Lyngbya and members of the Chlorophyceae such as
Chlorella Pseudococcomyxa and Pseudopleurococcus [Gorbushina et al (1987)
Calvo et al (1993) Arino et al (1996)]
They grow optimally on media with low water activity due to high salt or sugar
concentrations seem to propagate 70 vegetatively in the salterns and are thus
halotolerantosmotolerant species rather than simple flush-through occurrences
Cladiosporum herbarum was frequently isolated from hypersaline waters dead and dying
plant material air soil food fruit cereals paint and textiles (Ventosa 2004)
C) Algae
Most of the painted areas in temperature climate became covered with green algae
(Pleurococcus Protococcus and Trentopholia) while under tropical conditions blue green
algae of the genera Oscillatoria and Sytonema predominated (Garg 1995) The main
factors which contribute to the growth of algae on wall paintings are the presence of
moisture in the plaster as well as availability of visible light These conditions are quite
prevalent in the tropical climate but in temperature regions also algal growth on wall
paintings have been reported [Tonolo et al (1961) Pietrini et al (1991)]
D) Actinomycetes
Usually literature refers to specific aspects eg the occurrence of cyanobacteria
and algae in caves with natural openings to sunlight or those with artificial lighting fungi
and so forth Actinomycetes have been considered to be mainly confined to soils where
they find their natural habitat but despite intensive studies there are still many gaps in our
knowledge of the role played by actinomycetes in soil processes and biodegrations of
murals cave paintings (Groth et al 1999) In addition halophilic bacteria actinomycetes
and cyanobacteria are also capable of growing on salt-affected mural paintings
(Karbowska 2003)
Monte and Ferrari (1993) reviewed the mechanisms of biodeterioration in tombs
and underground churches The role of actinomycetes in the deterioration of frescoes in
hypogean environments was stressed by Agarossi et al (1985) Monte and Ferrari (1993)
Giacobini et al (1987) described the serious damage suffered by a whole series of famous
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
32 Review of Literature
frescoes in underground environments Actinomycetes were isolated from these mural
paintings located in crypts caves and tombs About 200 strains of actinomycetes were
isolated 60 of which were identified The most frequent species were Streptomyces albus
S cinereoruber S griseolus S vinaceus and some members of the Nocardia genus
Heterotrophic bacteria and actinomycetes were the most abundant microorganisms
on the frescoes of Etruscan tombs (Agarossi et al 1985) Bettini et al (1977) studied
some of the oldest Etruscan tombs (7th to 4th century BC) and found white-grey patinas
and spots from streptomycetes in the mural paintings They related the biodeterioration to
the microclimatic conditions (eg lower temperatures high RH) Monte and Ferrari (1993)
considered that colonization of the mural paintings was the result of selective competitive
and inhibitory dynamics among different microorganisms under different and changing
environmental conditions The pigments excreted by some actinomycetes were responsible
for the violet stains found on the walls of tombs in Tarquinia Similar stains were observed
in one of the Roman tombs the Circular Mausoleum the Necropolis of Carmona Spain
from which a Streptomyces sp producing violet pigments in culture media was isolated
214 Identification of biodeteriogens
The possibility of pigments and biodeteriogens identification in frescos and stone
monitoring is offered mostly by vibrational spectroscopy infrared thermography laser
induced fluorescence (LIF) laser induced breakdown spectroscopy (LIBS) XRF (X-Ray
Fluorescence) IR and UV emission Among them laser based methods allowing for in
situ or remote characterization of artwork surface were applied successfully for
prospecting diagnosis and maintenance (Colao et al 2005) The rep-PCR fingerprinting
of the isolates allowed determination of their genotypic diversity Studies that have
compared rep-PCR genomic fingerprint analysis with DNAndashDNA relatedness studies have
shown that the two techniques yield results that are in close agreement [Nick et al (1999)
Rademaker et al (2000)] These studies therefore suggest that rep-PCR fingerprinting can
be used as a genomic screening method to differentiate at the species level and to select
representatives for DNAndashDNA reassociation experiments (Heymann et al 2003)
The characterisation of bacteria was for example often limited to isolation from
group-specific media followed by microscopy [Sorlini et al (1987) Weirich (1989)
Tate et al (1990) and in more recent studies to morphological and physiological
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
33 Review of Literature
characteristics including miniaturised and automated systems such as API and BIOLOG
[Arroyo et al (1997) Jimmenez et al (2000) and Laiz et al (2000)] or to
chemotaxonomic characteristics [Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
Wagner et al (1994) demonstrated that conventional microbiological efforts can
fail to isolate all microorganisms present in natural samples DNA-based techniques used
to identify microorganisms have revealed only a smaller fraction of bacteria isolated from
artworks (Ward et al 1990 Rolleke et al 1996) Bacterial identification using molecular
techniques especially those including the sequencing of genes coding for ribosomal
16S rRNA is very important to study bacterial communities found on artefacts One such
method is Denaturing Gradient Gel Electrophoresis (DGGE) of PCR-amplified gene
fragments coding for rRNA (Muyzer et al 1993) that allows the separation of partial
16S rDNA amplified fragments of identical length but different sequence due to their
different melting behaviour in a gel system containing a gradient of denaturants
(Jimenez 2003)
Total genomic DNA was purified for 16S rRNA gene sequencing and rep-PCR
using a slight modification of the method of Pitcher et al (1989) as described by
Heyndrickx et al (1996) rep-PCR genomic fingerprinting was performed with the REP-
and (GTG)5 primers (Versalovic et al 1994) using the PCR conditions described
previously by Rademaker et al (1997) Electrophoresis and pattern analysis were further
performed as described by Heyrman et al (2003) 16S rRNA gene sequencing and
phylogenetic analysis were performed as described by Heyrman and Swings (2001)
Phylogenetic trees were constructed using the BioNumerics software (Applied Maths) by
applying the neighbour-joining and maximum-parsimony methods on a multiple alignment
similarity matrix The stability of relationships was assessed by a bootstrap analysis of
1000 datasets For determination of the G+C content and levels of DNAndashDNA
hybridization approximately 1 g biomass was harvested from agar plates DNA was
purified by using a combination of the protocols of Marmur (1961) and
Pitcher et al (1989) as described by Logan et al (2000) The G+C content of the DNA
was determined by HPLC (Mesbah et al 1989) using the further specifications given by
Logan et al (2000) DNAndashDNA hybridization experiments were performed using a
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
34 Review of Literature
modification of the microplate method of Ezaki et al (1989) as described by
Willems et al (2001)
215 Preservation and conservation
Nowadays the conservation and preservation of our cultural heritage is one of the
world main concerns particularly in Europe The increasing need for non-destructive
investigation tools has become a major issue as sampling is in most cases restricted in
view of the value or the uniqueness of the object Artworks as wall paintings in buildings
and monuments of historical interest are affected by environment physical (temperature
and humidity) and biological factors (biodeteriogens) and by human (pollutant releases)
impact and therefore modified over the time The term ldquoconservationrdquo may have many
different meanings in different fields Every intervention directed to the restoration and
safeguard of works of art is commonly considered as a conservation treatment For
example conservation can involve the cleaning procedures set up by chemists or the photo
documentation of the preservation of historical memory For the appropriate conservation
of works of art even the lighting systems in a museum or the control of the visitorrsquos
movements in a site should be monitored Chemical degradation which induces the flaking
of paintings and deterioration from rain wind dust and other environmental causes is
mainly responsible for the weakening of the porous structure and the surface layers of the
materials used in works of cultural heritage (Colao et al 2005)
216 Conservation history
Wall paintings are an integral part of monuments and sites and should be preserved
in situ Many of the problems affecting wall paintings are linked to the poor condition of
the building or structure its improper use lack of maintenance frequent repairs and
alterations Also frequent restorations unnecessary uncovering and use of inappropriate
methods and materials can result in irreparable damage Substandard and inadequate
practices and professional qualifications have led to unfortunate results It is for this reason
that an appropriate document covering the principles of proper conservation-restoration of
wall paintings is necessary
The Venice Charter (1964) has provided general principles for the conservation-
restoration of cultural heritage The Amsterdam Declaration (1975) introducing the
concept of integrated conservation and the Nara Document on Authenticity (1994) dealing
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
35 Review of Literature
with cultural diversity have expanded these principles Taking into account these and
additional relevant contributions such as the ICOM-CC Code of Ethics (1984) Document
of Pavia (1997) and ECCO Professional Guidelines (1997) the aim of this document is
to provide more specific principles for the protection preservation and the conservation
restoration of wall paintings This document therefore reflects basic and universally
applicable principles and practices and does not take into account particular problems of
regions or countries which can be supplemented at regional and national level by
providing further recommendations where necessary
217 Preservation techniques of the mural paintings
The removal of fat salts varnishes and pollutants from the surfaces of the works
of art are mostly done by chemical and mechanical methods At the end of the 19th
century the practices of restoration methods that do not inhibit further future interventions
was considered acceptable During the 1960s several chemicals such as polymeric resins
were synthesized and applied as a consolidation or protection agents The accepted idea
was that these substances could be removed at any time leaving a completely unaltered
substrate On the basis of origin archaeological objects can be classified as follows
(Carretti 2005)
1 Inorganic It includes siliceous and nonsiliceous materials Archaeological materials
produced from stones terracotta ceramics and glass can be included under siliceous
materials whereas objects made of metals can be included under nonsiliceous inorganic
materials Again metal objects can be classified as ferrous metals and non-ferrous metals
Objects made of iron are termed as ferrous metal objects whereas metal objects made from
other than iron is termed as non-ferrous metal objects
2 Organic It includes archival and anthropological materials Again archival materials
include paper bhojapatra tadapatra textiles wooden objects miniature paintings whereas
anthropological objects include bone and ivory leather feather and fur etc
In the past restoration of paintings and other old artwork often involved application
of acrylic resins to consolidate and protect them One of the most important tasks for
modern restorers is thus to remove these layers because it turns out that acrylic resins not
only by drastically changing the optics of the treated artwork but in many cases they
accelerate their degradation The scientists use an oil-in-water microemulsion with the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
36 Review of Literature
organic solvent para-xylene as the oil component The matrix makes the cleaning agent
viscous so that it cannot enter very far into the pores of a painting (Carretti 2005)
Nanoparticle treatment is the logical evolution of the Ferroni-Dini method
Dispersions of kinetically stable Ca (OH)2 nanoparticles in non-aqueous solvents solved
most of the drawbacks of the microsized powders Stable dispersions of calcium hydroxide
have been successfully applied (replacing polymers) as fixatives to re-adhere lifted paint
layers during many restoration workshops in Italy and in Europe as a consolidant The
FerronindashDini method (two steps the application of a saturated solution of ammonium
carbonate (NH4)2CO3 and the treatment with a barium hydroxide solution Ba(OH)2 also
called the barium method has long been the acknowledged method for the removal of
salts that threaten paintings reinforcing at the same time the porous structure However
commercially available carbonates and hydroxide powders have dimensions of several
micrometres much larger than the pores on the paint surface This means they donrsquot
penetrate the painting well and there is also a risk of damaging the artwork by a white
glaze forming on the surface (Berger 2006) Restoration should provide the reinforcement
of the porous structure and the consolidation of the surface layer of arte facts A few
simple principles can be considered to define the most appropriate restoration method
1) The treatment should be reversible so that one can revert to the original status of the
work of art at any desired time
2) All the applied chemicals must ensure the maximum durability and the chemical
inertness
3) The applied chemicals must invert the degradation processes without altering the
chemical composition of the artefacts and their physico-chemical and mechanical
properties (Baglioni 2006)
218 Commercial preservative used for preservation of mural paintings
Cleaning was done using soft brushes vacuum cleaner and Gumma paine (dough)
a natural latex sponge Areas near the window were very dirty with black soot and were
cleaned with micro fibrous cloths moistened with synperonic N (surfactant alkyl phenol
ethoxylate based on nonyl phenol) and neutralized with clean water In several places the
paint layers had separated from the substrate (exfoli-ation) In that cases loose paint flakes
were stuck back using Paraloid B72 (10 solution in ethanol) as sparingly as possible
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
37 Review of Literature
Paraloid was injected with syringe behind the exfoliated area twice pushed and held back
with Melinex (polyester film) until fixed on the third application (Bionda et al 2002)
In a period of significant growth of molds and intensive efforts to stop the mold
contamination some of the lines of certain paintings were obscured or faded Solutions of
ethanol formalin 91 and Thiabendazole (TBZ) were used but they were not very
effective Para-formaldehyde fumigation was adopted beginning in 1981 to establish an
emergency treatment sensitivity of microorganisms from studied samples was tested
against Desogen by adding 1-3 (v v) in serial dilutions The best concentration
3 (vv) was applied with a brush to prevent spreading of the spores In order to overcome
the problem of fungal attack suitable fungicides carbendizeme or kiroxy-I or 5 solute of
N formaldehyde can be used Shellac solution in spirit or 2 solution of polyvinaycletate
in toluene can be used as preservative and consolidantsTo control insect and fungal attack
fumigants like pyrethrum DDT or 5 solution of sodium penta chlorophenate in kerosene
oil 2 to 5 solution of PVA in toluene or 2 to 5 solution of paraloid B-72 in toluene or
acetone be used (Miura 2009) Microclimatic conditions constitute a critical factor in the
conservation of cave paintings The unstable microclimatic condition is one of the factors
that always affect the state of conservation of mural paintings In the environmental-
monument system knowledge of the functional environment and climatic conditions of the
surroundings are necessary for the identification of causes of decay (Singh 2011)
Furthermore the risk of formation of indoor bioaerosols in residential and public
buildings (offices schools museums etc) has attracted interest in the last years due to
socio-economic as well as sanitary reasons (Ripka 2005) Thus it is important in aspects of
health and maintenance of Cultural Heritage to analyse the complete microflora to further
develop biocides for harmful microorganisms and methods for restoration of damaged
objects of art The biocidal testing was carried out on one representative algal species of
the two classes of algae viz Chlorococcum sp (green) and Chroococcus sp (blue-green)
found to be common in all the samples Efficiency tests were carried out both in liquid as
well as solid media containing algal suspensions by adding a biocide solution of known
concentration and determining the growth of the microorganism after the incubation
period The biocides used for the past studies were
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
14 Review of Literature
Figure-28 Ceilings of Virupaksha temple Hampi
The murals on the walls of the navaranga (the central pillared hall) depict stories
from Bhagavatha and are excellent examples of 19th
century Mysore paintings The
Mallikarjunaswamy temple on the hill is one of the Panchalingas of Talakad and the
temple has a beautiful mural painting on the wall of the temple The Dariya Daulat Bagh
has excellent mural painting (Sasibhoosan 1987)
Figure-29 Paintings on the walls of Jagan mohan palace Mysore
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
15 Review of Literature
Figure-210 Painting of Raja woodeyar era
Kerala mural paintings are the frescos depicting mythology and legends which are
drawn on the walls of temples and churches in South India principally in Kerala Ancient
temples churches and palaces in Kerala South India display an abounding tradition of
mural paintings mostly dating back between the 9th to 12th centuries The murals of
Thirunadhikkara Cave Temple (now ceded to Tamilnadu) and Tiruvanchikulam are
considered the oldest relics of Keralarsquos own style of murals Fine mural paintings are
depicted in temples at Trikodithanam Ettumanur Vaikom Pundarikapuram
Udayanapuram Triprangode Guruvayoor Kumaranalloor Aymanam the Vadakkunathan
temple in Trichur and the Sri Padmanabhaswamy temple at Thiruvananthapuram Other
mural sites are in the churches at Edappally Vechur Cheppad and Mulanthuruthy and at
palaces such as the Krishnapuram Palace near Kayamkulam and the Padmanabhapuram
Palace
Figure-211 Kerala murals
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
16 Review of Literature
Figure-212 Murals paintings of Kerala temples
There are wall paintings in Badami in the Bijapur district Karnataka Some
excellent paintings exist in the Jain caves at Sitanavassal in Puddukkottai District of Tamil
Nadu Tamil Nadu gave exuberant and glorious expression to themes relating to Siva in the
temples of Panamalai and Kailashanatar in Kancheepuram In the 9th century Jain cave of
Sittannavasal in Tamil Nadu there is a marvellous lotus pond painted on the ceiling In
the heart of the Brihadeeswara temple in Thanjavur Tamil Nadu protected by massive
walls of stone are the finest paintings of the theme of Siva ever painted towards the end of
the 10th century (Sivaramamurthi 1992)
Figure-213 Kancheepuram Mural paintings
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
17 Review of Literature
Figure-214 Sculpture of Mahabalipuram
26 Methods of mural painting
In the history of mural several methods have been used The Buon fresco technique
consists of painting in pigment mixed with water on a thin layer of wet fresh lime mortar
or plaster The pigment is then absorbed by the wet plaster after a number of hours the
plaster dries and reacts with the air it is this chemical reaction which fixes the pigment
particles in the plaster After this the painting stays for a long time up to centuries in fresh
and brilliant colors A Secco painting is done on dry plaster The pigments thus require a
binding medium such as egg (tempera) glue or oil to attach the pigment to the wall
Mezzo-fresco is painted on nearly-dry plaster which is defined by the sixteenth-century
author Ignazio Pozzo as ldquofirm enough not to take a thumb-printrdquo so that the pigment only
penetrates slightly into the plaster Ancestral Hopi village archaeologists found that
fourteen kivas had painted murals and multiple layers of murals on the walls some with up
to twenty-seven layers of murals (Saturno 2006)
The colors used in painting are generally obtained from plants and minerals
Among them only such colors which are lime resistant are suitable for mural painting The
selection of proper colors for a mural painting is an important part of the work as the
longevity the painting depends on it Only mineral colors are preserved for a long time
which could be the reason for use of those colors in early days As per ldquoShilpa ratnardquo and
ldquoAgnipuranardquo the colors used in mural painting are white black red yellow blue and
green Yellow and red are from yellow ochre and red ochre Blue is generally indigo or
china blue White is the prepared wall and black is the carbon soot Mural paintings have
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
18 Review of Literature
survived centuries only on account of the identification and use of those colors which does
not have any reaction with lime (Miraseth 2006)
Originally three types of brushes were made and used flat medium and fine Flat
brushes were made from hairs behind calfrsquos ear the medium from the bottom of goats
belly and the fine brush from delicate blades of grass However in due course of time and
change use of easily available brushes from commercial market and shading of the
original colours can be distinctively noticed The use of blue colour is also noticed over the
passage of time The paintings have been brought down from the walls to plywood cloth
paper and other frames for easy to make and use purposes (Chakarabarti 1980)
27 Themes of mural painting
The subjects and themes in the murals are centered on the Hindu pantheon of Gods
and Goddesses drawn from description in the invocatory verses or Dhyana Slokas More
common representations are of Vishnu in different incarnations Ganesha and
manifestations of Siva We see murals in the Pallimanna Siva Temple devoted to Siva-
Parvatirsquos marriage the Ramayana Story being narrated on the walls of the Mattancheri
palace in the Sankara Narayana the Mahabharata is retold Murals are various scenes from
the Hindu epics and also the frolics of Lord Krishna
It would be interesting to bring into account the influence of the mural paintings on
Christianity On various churches like the St Georgersquos Orthodox Church has Christian
murals bringing out biblical characters and narrating stories from the scriptures Mar
Sabore and Afroth Church at Akapparambu in the outskirts of Ernakulam also have murals
of scenes from the bible Interestingly StMaryrsquos Church at Kanjoor has on both sides of its
entrance a battle scene between the armies of Tipu Sultan and of the English East India
Company It is also apparent that the history of Kerala Murals has its origin in the temple
walls and thus a study of Kerala Murals is not complete without pondering on the
architecture of Kerala its association with the murals (Warrier 2011)
28 Technique used in mural paintings
Indian murals executed on walls of caves structural temples walls of palaces were
based on highly developed techniques Mural painting is a composite structure of these
three basic layers the support the ground and the pigment layer In case of wall painting
the wall itself is the support This is followed by the layer or layers of plaster which
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
19 Review of Literature
constitute the ground The pigment layer is the one which contains the picture The support
is the wall which may be rock surface in a cave or a structural one These stone surfaces
which serve as carriers are rough or uneven This unevenness is itself an advantage as it
provides ldquotoothrdquo to hold the plaster on the surface The uneven surface of the wall has to be
made uniform with layers of plaster in successive gradation of fineness There is generally
one layer of rough plaster followed by one or more layers of fine plaster Ground or plaster
is a term used to mean the surface material of a wall or building which is applied as a
plastic mass made by mixing certain materials with water letting the mass set by drying
carbonation or hydration The active or setting components of plaster are commonly clay
which sets by drying lime which sets by carbonation gypsum and pozzolana which sets by
hydration (Mini 2010)
There are different mixtures for rough plaster In all the mixtures clay limestone
lime and shells in powdered form serve as the matrix The particles of which are held
together by the organic materials like gum glue extracts from barks etc are in fact
adhesives The fine plaster layer requires more careful preparation because it is the layer on
which the pigments are laid to make the picture ldquoShilparatnardquo suggest a mixture of conch
Oyster shells or white clay with gum of neem or slaked lime and coconut water Here the
consolidation is effected by the carbonation of slaked lime ie it absorbs carbon dioxide
from air and becomes carbonate Mural paintings were lime-washed from the 17th until the
beginning of 19th century A few paintings in vaults were never lime-washed for example
at Taby and Floda painted by the medieval painter Albertus Pictor (Mini 2010)
All the paintings have certain basic common characteristics There has to be a wall
or rock surface called support over which the artist goes to work A plaster base called
ground of varied thickness is laid on the support The ground may consist of one or more
layers The strength and life of the whole mural depended up on this ground over which the
painting was done It is the process of applying the final painting on the ground determines
the character of the mural whether it is fresco or tempera The mural painting is done
usually by creating wall surface free of any previous oil or paint by using solvent or by
sand blasting The brick wall is first plastered with mixture of lime and sand in the ratio of
12 A mixture of egg yolk vinegar oil colour is used in dry plaster
There are at least six stages before a Kerala Mural Painting is complete Lekhya
Karma is the first stage where sketching by pencil or crayon is done The second stage is
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
20 Review of Literature
the Rekha Karma which enhances the outlines of the sketching done The third stage called
Varna Karma breathes life into the painting with its colours Here all colours are
appropriately filled in The colouring of the human figures is done according to the
characters and their common virtues The divine and noble characters (Saatvik) are painted
in green those inclined towards power and wealth (Raajasik) is painted in shades of red
lowly mean characters (Tamasik) in white and demons in black In the fourth stage or the
Vartana Karma shading is done Fifth stage called the Lekha Karma brings us to the final
outline of the painting which is usually in black The final and the finishing touches stage
are called Devika Karma (Warrier 2011)
29 Dyes used in mural painting
Indians have been considered as fore runners in the art of natural dyeing Natural
dyes find use in the colouring of textiles drugs cosmetics etc Owing to their non-toxic
effects they are also used for colouring various food products In India there are more
than 450 plants that can yield dyes In addition to their dye-yielding characteristics some
of these plants also possess medicinal value Though there is a large plant resource base
little has been exploited so far Due to lack of availability of precise technical knowledge
on the extracting and dyeing technique it has not commercially succeeded like the
synthetic dyes (Siva 2007)
The color materials on the mural paintings in ancient India were derived from the
natural materials like terracotta chalk red ochre and yellow ochre mixed with animal fat
The dyes for painting is prepared such as white from lime Black from carbon soot of
lamps Red and yellow from minerals Blue from indigo ferra Deep red from lac A fine
coating of resin is done after the painting in order to make a shining appearance Egg yolk
and vinegar was mixed with oil colors and painted on dry plaster (Krishnakumar 1999)
Although plants exhibit a wide range of colours not all of these pigments can be
used as dyes Some do not dissolve in water some cannot be adsorbed onto fibres whereas
others fade when washed or exposed to air or sunlight It remains a mystery why plants
reward us with vibrant dyes India has a rich biodiversity and it is not only one of the
worldrsquos twelve mega diversity countries but also one of the eight major centres of origin
and diversification of domesticated taxa It has approximately 490000 plant species of
which about 17500 are angiosperms more than 400 are domesticated crop species and
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
21 Review of Literature
almost an equal number their wild relatives Thus India harbours a wealth of useful
germplasm resources and there is no doubt that the plant kingdom is a treasure-house of
diverse natural products One such product from nature is the dye (Siva 2007)
Many natural dyestuff and stains were obtained mainly from plants and dominated
as sources of natural dyes producing different colours like red yellow blue black brown
and a combination of these Almost all parts of the plants like root bark leaf fruit wood
seed flower etc produce dyes It is interesting to note that over 2000 pigments are
synthesized by various parts of plants of which only about 150 have been commercially
exploited Nearly 450 taxa are known to yield dyes in India alone of which 50 are
considered to be the most important ten of these are from roots four from barks five from
leaves seven from flowers seven from fruits three from seeds eight from wood and three
from gums and resins Some important dye-yielding plant habitats their distribution and
colouring pigment (Siva 2007)
The dye is generally prepared by boiling the crushed powder with water but
sometimes it is left to steep in cold water The solution then obtained is used generally to
dye coarse cotton fabrics Alum is generally used as a mordant Flowers of Butea
monosperma (Lam) Taubert yield an orange-coloured dye which is not fast and is easily
washed away For the purpose of colouring the material is steeped in a hot or cold
decoction of the flowers A more permanent colour is produced either by first preparing the
cloth with alum and wood ash or by adding these substances to the dye-bath The dye
indigo is produced by steeping the plant in water and allowing it to ferment This is
followed by oxidation of the solution with air in a separate vessel Mallotus philippinensis
muell yields an orange colour used for dyeing silk and wool To prepare the annatto dye
from B orellena the fruits are collected when nearly ripe The seeds and pulp are removed
from the mature fruit and macerated with water Thereafter they are either ground up into
an lsquoannatto pastersquo or dried and marketed as annatto seeds Sometimes when the seeds and
pulp are macerated with water the product is stained through a sieve and the colouring
matter which settles out is collected and partially evaporated by heat and finally dried in
the sun (Sowbhagya 2002)
The predominant colors used in rock art and cave art are black (from charcoal soot
or manganese oxide) yellow ochre (limonite) red ochre (hematite or baked limonite) and
white (kaolin clay burnt shells powdered gypsum or powdered calcium carbonate) All of
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
22 Review of Literature
theses pigments may be used on leather or raw hide as well Early cave art in Seminole
Canyon was monochromatic in red and as culture grew more sophisticated the color
palette expanded Blue Orange Brown Green and Purple are the most common colours
used in Ajantha murals White Pink Gold are occasionally represented mineral earths
containing ferric oxide and copper carbonates were used as source of red yellow and green
colours There is also evidence to establish that root of Rubia cardifolia and leaves of
Indigofera tinctoria were used as source for red and blue colours (Nayer et al 1999)
Many colors of pigments were obtained from both organic and inorganic sources in
ancient times and used to paint various surfaces such as braintan leather clothing and
accoutrements rawhide the human body etc Blue color was obtained from powdered
azurite and lapis duck manure and certain clays Fine Blue-green clay was obtained from
deposits near Mankato Michigan Organic sources of blue include Turkeys Tail a
greenish blue polypore that grows on dead decaying wood (not tannish ones) Native
Americans get Indigo from either Guatemala or Ecuador which was traded well up onto
Kansas long before the Spanish ever set foot here American Indigo has purple tones to it
but IndianJapanese indigo has green tones Berries and crushed flowers were also used to
obtain blue color by rubbing the plant material directly on the leather
An organic source of red was Cochineal It was native west of the Mississippi and
is produced from the bodies of small insects that grow on the prickly pear cactus Ladys
Bedstraw gives a good vermillion red color Harvest the roots dry them out clean the mud
etc off of them and then grind the roots really fine then soak them to extract the red
coloring The key here is drying the root first Blood was also used as red pigment Pucoon
roots also yield a red pigment (Smith 2002) Red ochre the reverse original red colours are
due to variations in iron oxide (or) calcite content and to redox conditions in the firing
produced Brown coloured ceramics owe their colour to maghemite and must be
considered as a fabrication defect due to the position of the ceramic piece in a zone where a
reducing atmosphere prevailed in the course of firingRed pigments were produced from
iron oxides like hematite or limonite and from ochre Hematite was the most frequently
used mineral It occurs in the form of aggregates of small red crystals or in the form of
bigger black crystals which are difficult to crush white was obtained mostly from
kaolinite or illite (Clottes et al 1990)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
23 Review of Literature
210 Biodetoriation of mural paintings
Historic items often contain natural biodegradable materials and have histories of
exposure to moist conditions These two conditions make them amenable to microbial
attack Microbial colonization may damage the building or the cultural asset
(Salonen 2001) Biodeteriogens are organisms involved in deterioration of artifacts They
are very specific for each type of artifact in accordance with its chemical structure and
environment They also have different nutritional requirements and act directly or
indirectly on the substrate The adhesion of microorganisms to a substrate is the result of
cell hydrophobicity and of excreted polymeric substances contained by sheaths capsules
and slimes (Colao 2005)
The surviving wall paintings and decorations in subterranean environments around
Malta are rather scarce (Buhagiar 1986 1993 1998) These include those at St Paulrsquos
Catacombs (Zammit 2008) St Agatharsquos Crypt and Catacombs (Camilleri 2001)
San Catald Catacombs Tac-Cghaqi Abbatija tad-Dejr (Buhagiar 1993) all in Rabat the
cave-sanctuary in Mellieħa (Buhagiar 1987) and the Ħal Saflieni Hypogeum in Paola
(Pace 2000) Previous studies conducted on wall paintings and decorations in Maltese
Palaeo-Christian Catacombs have involved their manufacturing techniques (Muscat 2005)
However to date limited systematic studies have been conducted into the biodeterioration
in Maltese Palaeo- Christian Catacombs The only such studies ever conducted in Malta
concerned the biodeterioration of works of art in catacombs have been carried out at St
Agatharsquos Crypt and Catacombs in Rabat (Zammit et al 2008 Psaila 2006)
Microorganisms can be responsible for the destruction of monuments buildings
and cultural heritage assets including the decay of concrete cement stones mural
paintings etc These microorganisms are not only related with biodeterioration but water-
damaged indoor building materials are frequently colonized by complex bacterial
communities and may emit mixed bioaerosols into the indoor air (Jimenez 2000) It is
well known that mural paintings are colonized by micro-organisms and can be severely
damaged by such growths (Ciferri 1999) A large number of fungal (gt50) and bacterial
taxa (70) have been detected in indoor environments Over 50 bacterial species and 14
genera novel to science were reported in the past 10 years from indoor air and historic
items indicating bacterigravea in these enviroments are as yet only fragmentarily known
(Salonen 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
24 Review of Literature
Traditionally the study of microflora which causes this biodeterioration was based
on classical cultivation methods that were mainly useful to study the physiological
potential of microorganisms but do not provide information on all microbial communities
to be found in excavated artifacts Indeed many studies using culture-independent
techniques which cultivate microorganisms from different environments may often
represent only minor components of the microbial community as a whole It is generally
accepted that cultivation methods recover less than 1 of the total microorganisms present
in environmental samples (Ward et al 1990 Amann et al 1995) Hence microbial
investigations based only on cultivation strategies cannot be regarded as reliable in terms
of reflecting the microbial diversity present in objects of art (Osburn et al 2011)
Early workers suggested that the presence of living microorganisms on stone
increased its susceptibility to damage through their water-binding capacity It has recently
been reported that the mineralogy porosity surface roughness and capacity to collect
water and organic materials control its bioreceptivity and tendency to biodeterioration
(Diakumaku 1995) In addition environmental factors as temperature light pH and
relative humidity affect the number and type of colonising species (Tiano et al 1995) and
hence the progress of colonisation Biofilms on decayed stones consist on mixed microbial
populations embedded in a polymeric matrix Fungi algae filamentous and unicellular
bacteria are found in these complex communities A variety of bacteria have been isolated
from different stone samples confirming the dominance of Gram-positive organisms
especially spore-forming bacteria such as Bacillus and filamentous actinomycetes
(Ripka 2005)
In cultivation studies of deteriorated mural and rock paintings bacterial isolates
have frequently been attributed to the genus Bacillus (Weirich 1989 Tate and Rebrikova
1991 Gonzalez et al 1999 Heyrman et al 1999 Jimenez et al 2000) Other studies that
have included DNA-based techniques to characterize the bacterial community involved in
biodeterioration have shown that a substantial part of the bacterial population is made up of
so far unknown species (Altenburger et al 1996 Rolleke et al 1996 Gurtner et al 2000
Heyrman and Swings 2001) (Heymann et al 2003)
Many potential mycotoxin producers have been detected in air and items from
indoor environments with histories of exposure to moisture for example species of
Acremonium Alternaria Aspergillus Chateomium Fusarium Eurotium Paecilomyces
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
25 Review of Literature
Penicillium Scopulariopsis Stachybotrys Trichoderma Verticillium and Wallemia
(Peltola et al 2001 Pieckova et al 2001) Not all strains of one species produce
mycotoxins and different strains may produce different toxins Whereas toxin producing
strains are frequent in crops and outdoor vegetation toxin producing isolates from indoor
environments and non living assets have only been reported of the species Aspergillus
versicolor (Nielsen et al 1998) Stachybotrys chartarum Nikulin (1997) and
Trichoderma harzianum (Peltola et al 2001) Streptomyces griseus strains producing
valinomycin occur in environments where humans can get exposed
(Andersson et al 2002) The biological properties and toxicity mechanisms of cereulide
were identical to those by valinomycin (Mikkola et al 1999 Salonen et al 2001)
The genus Paenibacillus was first proposed by Ash et al (1993) and its description
was emended by Shida et al (1997) The genus Paenibacillus is under intensive taxonomic
investigation with ten species having been formally described in the last year Heyrman amp
Swings (2001) isolated a strain originally classified as Paenibacillus sp LMG 19508
from biodeteriorated mural paintings in the Servilia tomb at the Roman necropolis of
Carmona in Seville Spain (Smerda et al 2006) Building stone and wall paintings contain
a variety of hydroscopic salts including carbonates chlorides nitrates sulfates etc
dispersed within the porous material or locally concentrated These salts are solubilised
and migrate with the water in and out of the stone Due to changes in physical parameters
the so called salt efflorescences appear on the surfaces providing extremely saline
environments and building niches for settlement of halophilic microorganisms Halite and
other hygroscopic salts can retain considerable quantities of moisture when entrapped in
the building materials and thus favouring the bacterial growth (Ripka 2005)
It is demonstrated that water-damaged indoor building materials contained
substances of microbial origin extremely toxic to eukaryotic cells and large quantities of
several microbial species known to be potentially toxic or immunopotentiating These
include peptidoglycans Gram-negative endotoxin β-13-D glucans lipoglycans and
teichoic acids and mycotoxins (Jimenez 2000) In turn these microorganisms can mediate
the crystallization process These crystallizations can produce destructive effects Some
salts may crystallize or recrystallize to different hydrates which occupy a larger space and
exert additional pressure producing cracking powdering and flaking
(Jimenez and Laiz 2000)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
26 Review of Literature
211 Types of deterioration on mural paintings
The frescos represent a variety of ecological niches where primary colonization is
due to photoautotrophic and chemolithoautotrophic microorganisms followed by
secondary colonization due to heterotrophic bacteria that obtain nutrients from various
sources (metabolites of autotrophic bacteria airborne organic contamination animal faeces
and organic compounds in the paint layers themselves) Microbial-induced deterioration
processes cause structural as well as aesthetic damage to wall paintings such as the
discoloration of materials the formation of crusts on surfaces and the loss of material
(Sarro et al 2006 Osburn et al 2011) Halophilic bacteria and archaea were thought to
be found only in extreme environments like salt lakes or black smokers However it has
been shown that mural paintings and stones are a common habitat for extremely salt
tolerant and moderate halophilic (Ripka 2005) Microbial induced deterioration processes
can cause different kinds of alterations such as discolouration of materials the formation of
crusts on surfaces and the loss of material which leads to structural damage (Ripka 2005)
First of all microorganisms can cause severe problems due to the excretion of aggressive
metabolic products such as organic or inorganic acids Secondly material components can
be used as substrates for microbial metabolism Exoenzymes such as cellulases proteases
tannases beta-glucosidase produced by fungi and bacteria are responsible for hydrolysis of
cellulose and proteins Further examples are mechanical processes caused by swelling and
shrinking of slime or mycelia penetrating inside plaster of the painting resulting in loss of
cohesion and detachment of the paint layer (Rolleke 1996 Gurtner et al 2000)
Table-21 Microbial damage on mural paintings (Rolleke 1996)
S No Damage Microbial activity
1 Green brown red grey
surface layers (patinas)
Pigments produced by microorganisms (intra-or
extracellular) as chlorophyll and carotinoids
2 Dislodging of painting layers Use of organic binders as nutrient and energy
source
3 Acid attack of carbonates Acid produced by fungi or bacteria
4 Discolouration of pigments Redox-reactions induced by fungi and
bacteria
5 Loss of paint layer Growth of microorganisms deep into the plaster
6 Hydrolysis of synthetic
polymers Chemoorganotrophic activity of bacteria and fungi
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
27 Review of Literature
Discolorations are caused by excretion of pigments and microbiologically induced
reductionoxidation-processes (Krumbein et al 1990) Degradation of the bindings is
followed by reduction of stability Oxidation of ammonium and reduced sulphur
compounds results in acidification of the environment such as Sulphuric acid and the
variety of organic acids produced by the heterotrophs cause solubilization of calcareous
binding material and chelation of metal ions (Bock et al 1993) It is now well recognised
that wall paintings can be deteriorated by microorganisms (Ciferri 1999)The growth of
microorganisms essentially results in two types of damage aesthetic and structural
Aesthetic damage implies pigment discoloration stains and formation of a biofilm on the
painted surface Structural damage is observed as cracking and disintegration of the paint
layer formation of paint blisters and degradation of support polymers or of glues and
binders resulting in detachment of paint layer from the support The colonization of mural
paintings by bacteria and other microorganisms can have different causes Provided that
favorable environmental conditions occur nutrients for heterotrophic bacteria and fungi
can be available from metabolites of autotrophic bacteria from airborne contamination and
dripping water from animal faeces but also from organic compounds in the paint layer
itself
212 Methods of studying biodeterioration
It is now well recognized that wall paintings may be deteriorated by
microorganisms as established by several studies that linked the observed damage with the
microbial community present as reviewed by Ciferri (1999) Despite this knowledge a
reliable characterization of bacteria associated with such damage is often lacking To
obtain greater insight into the bacterial community involved in biodeterioration of mural
paintings three sites (from the necropolis at Carmona Spain and the Saint-Catherine
chapel of the castle at Herberstein Austria) were sampled In previous studies from these
sites 385 isolates were analysed by fatty acid methyl ester GC and representatives of
different fatty acid clusters were further studied by 16S rRNA gene sequencing
(Heyrman and Swings 2001) Several of these representative strains showed the highest
sequence similarity with members of the genus Arthrobacter (Heyrman et al 2005)
Jimenez and Samson (1981) analysed the microbial flora of a large fresco painted
in the late 1920s in the monastery ldquoSanta Maria de la Rabidardquo (Huelva Spain) exhibiting
two types of deterioration white efflorescence and green-to-black stains
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
28 Review of Literature
Tate and Rebrikova (1990) thought autotrophic nitrifying bacteria to be the first colonisers
of damaged frescoes and building materials in the cathedral of the nativity of the Virgin in
the Pafnutii-Borovskii monastery (Russia) The bulk of research on biodeterioration of
mural paintings has focused on explaining the observed phenomena by analysing the
microflora present Following this approach a precise characterisation of the
microorganisms using a polyphasic approach was never the first goal
Only a few studies included genomic fingerprinting (16S rDNA sequence analysis)
for the characterisation of bacteria associated with damage on mural paintings
[Rolleke (1996) Pinar et al (2001)] Previous studies based on culture-dependent
techniques showed that the flora present on frescos are fungi (predominant species of
Penicillium Aspergillus Cladosporium and Engyodontium) (Guglielminetti et al 1994)
bacteria (predominant species of Bacillus Arthrobacter Micrococcus Streptomyces and
Pseudomonas) (Heyrman et al 1999) cyanobacteria and eukaryotic algae (species of
Nostoc Lyngbya and Chlorophyceae) (Arino et al 1996 Calvo et al 1993) The killing
effect of an antimicrobial agent on a microorganism can be assessed in several ways
(1) Lethal activity may be expressed as the rate of killing by a fixed concentration
of drug under controlled conditions This rate is determined by measuring the number of
viable bacteria at various time intervals The resulting graphic depiction is known as the
time-kill curve Bacterial killing rates are in part dependent on the class of antibiotic and
the concentration of this agent With certain classes of antibiotics (eg aminoglycosides
and fluoroquino-lones) the rate of killing increases with increased drug concentrations up
to a point of maximum effect This is termed concentration-dependent bactericidal activity
In contrast the killing rates of szlig-lactam agents and vancomycin are relatively slow and
continue only as long as the concentrations are in excess of the MIC This rate of killing is
termed time-dependent bactericidal activity
(2) The minimal concentration of drug needed to kill most of the viable organisms
after incubation for a fixed length of time (generally 24 hours) under a given set of
conditions is the most common estimation of bactericidal activity and is known as either
the minimal bactericidal concentration (MBC) or the minimal lethal concentration (MLC)
It will be referred to in this document as the MBC Unfortunately the definition of the
MBC (999 killing of the final inoculum) is somewhat arbitrary and separates the
bacteria into two populations ndash a segrega-tion which might not have biological relevance
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
29 Review of Literature
The determination of the MBC moreover is so subject to methodologic variables that the
clinical relevance of MBCs is nearly impossible to assess particularly for certain pathogen
and drug combinations (eg Staphylococci and beta-lactam agents)
(3) The serum of a patient receiving an antibiotic may be tested against the
infecting microorganism This can be done using time-kill curve methodology (ie serum
bactericidal rate) or using dilution methodology (ie serum bactericidal titer) The
principles of these methods as well as the influence of biological and technical factors are
similar (Barry et al 1999)
213 Microbial flora associated with deteriorated mural paintings
A great deal of research has been done in this field mainly by using cultivation dependent
methods However by using culture-dependent methods only a very small proportion of
microorganisms can be obtained Far less than 1 of organisms in the environment can be
cultivated by standard cultivation techniques (Pace 1996) Recent studies have shown that
culture-dependent techniques yielded mainly sporeforming bacteria suggesting that plating
leads to an over estimation of the number of spore-forming bacteria A wide number of
investigations have shown that in addition to chemical and physical processes
microorganisms play a major role in degradation of objects of art such as paintings stone-
works wood paper masonry leather parchment glass and metal (Ripka 2005)
A) Bacteria
In general growth of diverse organisms on mural paintings is supported by
humidity slight alkaline pH values and the presence of organic and inorganic nutrient
sources (Weirich 1989) In mural paintings pigments are suspended in water or oil often
binders such as casein and milk are used and they are supplied on the damp lime plaster
(Ciferri 1999) The calcium carbonate formed on contact with air consolidates the
pigments Thus frescos contain mainly inorganic components While chemoautotrophic
nitrifiers and thiobacilli obtain their energy for growth by oxidizing ammonium and
reducing sulphur-compounds respectively heterotrophic bacteria and fungi depend on
organically bound carbon [Tate et al (1991) Lazar (1971) Petushkova et al (1986)
Jimenez et al (1981)] Thus primary colonization of photoautotrophic Cyanobacteria
chemolithoautotrophic nitrifying bacteria and sulphuric acid producing thiobacilli represent
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
30 Review of Literature
the first supply of organic matter The death and lysis of such bacteria promotes the
secondary settlement of heterotrophic bacteria and fungal populations (Calvo et al 1991)
Bacteria may derive from plants or pollen as many sequences obtained in this study
gave high score similarities with bacteria isolated from plants like Moraxella osloensis
Enterobacter cloace Enterobacter agglomerans and Pantoea endophytica Bacteria may
also derive from animal faeces like flies Bacillus Pseudomonas Aeromonas and Panteoa
(Ripka 2005) As Lazar and Dumitru (1973) reported studying mural paintings in a
Romanian monastery the genera Bacillus Arthrobacter and Pseudomonas have been
proved to produce salt efflorescences and were even considered to cause the blanching
phenomenon of frescoes (Jimenez et al 2000) Predominant bacterial genera are Bacillus
Streptomyces Arthrobacter Micrococcus and Pseudomonas [Weirich (1989)
Tate et al (1990) Arroyo et al (1997) Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
B) Fungi
It may be concluded that there is wide variety of fungal forms present on mural
paintings but Aspergillus and Alternaria were found dominating from all the experimental
sites next to them were Cladosporium Drechestera Fusarium Curvularia Chaetomium
Memnoniella Mycelia sterelai Pencillium Emericella Stachybotrytis Trichoderma
Phoma Monodictys Humicola and Epicoccum (Garg et al 1995)
The fungal genera most commonly found in lists of isolated taxa given in literature
are Alternaria Aspergillus Chaetomium Cladosporium Fusarium Penicillium and
Verticullum [Weirich (1989) Tate et al (1990) Guglielminetti et al (1994)
Garg et al (1995) Berner et al (1997) Ciferri (1999)] Some fungi having hard fruiting
bodies represented by sclerotia pycnidia perithecia cleistothecia and stroma could
organize themselves inside the painted layer Many fungal forms having such structures
were identified from our experimental sites viz Emericella nidulans A flavus
Chaetomium sp and Phoma sp etc These structures with little increase in humidity may
cause swelling in the paint film (Garg 1995)
Strains of species of Alternaria and Cladosporium both of them identified on the
mural paintings of the Palace of Schoumlnbrunn are the most common genera isolated from
stone and mural paintings in indoor environments with standard cultivation methods
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
31 Review of Literature
(Ventosa 2004) Saprophytic species of the genus Cladosporium are among the most
abundant fungi isolated in saltern samples Commonly isolated Cyanobacteria belong to
Nostoc and eukaryotic algae to Lyngbya and members of the Chlorophyceae such as
Chlorella Pseudococcomyxa and Pseudopleurococcus [Gorbushina et al (1987)
Calvo et al (1993) Arino et al (1996)]
They grow optimally on media with low water activity due to high salt or sugar
concentrations seem to propagate 70 vegetatively in the salterns and are thus
halotolerantosmotolerant species rather than simple flush-through occurrences
Cladiosporum herbarum was frequently isolated from hypersaline waters dead and dying
plant material air soil food fruit cereals paint and textiles (Ventosa 2004)
C) Algae
Most of the painted areas in temperature climate became covered with green algae
(Pleurococcus Protococcus and Trentopholia) while under tropical conditions blue green
algae of the genera Oscillatoria and Sytonema predominated (Garg 1995) The main
factors which contribute to the growth of algae on wall paintings are the presence of
moisture in the plaster as well as availability of visible light These conditions are quite
prevalent in the tropical climate but in temperature regions also algal growth on wall
paintings have been reported [Tonolo et al (1961) Pietrini et al (1991)]
D) Actinomycetes
Usually literature refers to specific aspects eg the occurrence of cyanobacteria
and algae in caves with natural openings to sunlight or those with artificial lighting fungi
and so forth Actinomycetes have been considered to be mainly confined to soils where
they find their natural habitat but despite intensive studies there are still many gaps in our
knowledge of the role played by actinomycetes in soil processes and biodegrations of
murals cave paintings (Groth et al 1999) In addition halophilic bacteria actinomycetes
and cyanobacteria are also capable of growing on salt-affected mural paintings
(Karbowska 2003)
Monte and Ferrari (1993) reviewed the mechanisms of biodeterioration in tombs
and underground churches The role of actinomycetes in the deterioration of frescoes in
hypogean environments was stressed by Agarossi et al (1985) Monte and Ferrari (1993)
Giacobini et al (1987) described the serious damage suffered by a whole series of famous
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
32 Review of Literature
frescoes in underground environments Actinomycetes were isolated from these mural
paintings located in crypts caves and tombs About 200 strains of actinomycetes were
isolated 60 of which were identified The most frequent species were Streptomyces albus
S cinereoruber S griseolus S vinaceus and some members of the Nocardia genus
Heterotrophic bacteria and actinomycetes were the most abundant microorganisms
on the frescoes of Etruscan tombs (Agarossi et al 1985) Bettini et al (1977) studied
some of the oldest Etruscan tombs (7th to 4th century BC) and found white-grey patinas
and spots from streptomycetes in the mural paintings They related the biodeterioration to
the microclimatic conditions (eg lower temperatures high RH) Monte and Ferrari (1993)
considered that colonization of the mural paintings was the result of selective competitive
and inhibitory dynamics among different microorganisms under different and changing
environmental conditions The pigments excreted by some actinomycetes were responsible
for the violet stains found on the walls of tombs in Tarquinia Similar stains were observed
in one of the Roman tombs the Circular Mausoleum the Necropolis of Carmona Spain
from which a Streptomyces sp producing violet pigments in culture media was isolated
214 Identification of biodeteriogens
The possibility of pigments and biodeteriogens identification in frescos and stone
monitoring is offered mostly by vibrational spectroscopy infrared thermography laser
induced fluorescence (LIF) laser induced breakdown spectroscopy (LIBS) XRF (X-Ray
Fluorescence) IR and UV emission Among them laser based methods allowing for in
situ or remote characterization of artwork surface were applied successfully for
prospecting diagnosis and maintenance (Colao et al 2005) The rep-PCR fingerprinting
of the isolates allowed determination of their genotypic diversity Studies that have
compared rep-PCR genomic fingerprint analysis with DNAndashDNA relatedness studies have
shown that the two techniques yield results that are in close agreement [Nick et al (1999)
Rademaker et al (2000)] These studies therefore suggest that rep-PCR fingerprinting can
be used as a genomic screening method to differentiate at the species level and to select
representatives for DNAndashDNA reassociation experiments (Heymann et al 2003)
The characterisation of bacteria was for example often limited to isolation from
group-specific media followed by microscopy [Sorlini et al (1987) Weirich (1989)
Tate et al (1990) and in more recent studies to morphological and physiological
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
33 Review of Literature
characteristics including miniaturised and automated systems such as API and BIOLOG
[Arroyo et al (1997) Jimmenez et al (2000) and Laiz et al (2000)] or to
chemotaxonomic characteristics [Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
Wagner et al (1994) demonstrated that conventional microbiological efforts can
fail to isolate all microorganisms present in natural samples DNA-based techniques used
to identify microorganisms have revealed only a smaller fraction of bacteria isolated from
artworks (Ward et al 1990 Rolleke et al 1996) Bacterial identification using molecular
techniques especially those including the sequencing of genes coding for ribosomal
16S rRNA is very important to study bacterial communities found on artefacts One such
method is Denaturing Gradient Gel Electrophoresis (DGGE) of PCR-amplified gene
fragments coding for rRNA (Muyzer et al 1993) that allows the separation of partial
16S rDNA amplified fragments of identical length but different sequence due to their
different melting behaviour in a gel system containing a gradient of denaturants
(Jimenez 2003)
Total genomic DNA was purified for 16S rRNA gene sequencing and rep-PCR
using a slight modification of the method of Pitcher et al (1989) as described by
Heyndrickx et al (1996) rep-PCR genomic fingerprinting was performed with the REP-
and (GTG)5 primers (Versalovic et al 1994) using the PCR conditions described
previously by Rademaker et al (1997) Electrophoresis and pattern analysis were further
performed as described by Heyrman et al (2003) 16S rRNA gene sequencing and
phylogenetic analysis were performed as described by Heyrman and Swings (2001)
Phylogenetic trees were constructed using the BioNumerics software (Applied Maths) by
applying the neighbour-joining and maximum-parsimony methods on a multiple alignment
similarity matrix The stability of relationships was assessed by a bootstrap analysis of
1000 datasets For determination of the G+C content and levels of DNAndashDNA
hybridization approximately 1 g biomass was harvested from agar plates DNA was
purified by using a combination of the protocols of Marmur (1961) and
Pitcher et al (1989) as described by Logan et al (2000) The G+C content of the DNA
was determined by HPLC (Mesbah et al 1989) using the further specifications given by
Logan et al (2000) DNAndashDNA hybridization experiments were performed using a
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
34 Review of Literature
modification of the microplate method of Ezaki et al (1989) as described by
Willems et al (2001)
215 Preservation and conservation
Nowadays the conservation and preservation of our cultural heritage is one of the
world main concerns particularly in Europe The increasing need for non-destructive
investigation tools has become a major issue as sampling is in most cases restricted in
view of the value or the uniqueness of the object Artworks as wall paintings in buildings
and monuments of historical interest are affected by environment physical (temperature
and humidity) and biological factors (biodeteriogens) and by human (pollutant releases)
impact and therefore modified over the time The term ldquoconservationrdquo may have many
different meanings in different fields Every intervention directed to the restoration and
safeguard of works of art is commonly considered as a conservation treatment For
example conservation can involve the cleaning procedures set up by chemists or the photo
documentation of the preservation of historical memory For the appropriate conservation
of works of art even the lighting systems in a museum or the control of the visitorrsquos
movements in a site should be monitored Chemical degradation which induces the flaking
of paintings and deterioration from rain wind dust and other environmental causes is
mainly responsible for the weakening of the porous structure and the surface layers of the
materials used in works of cultural heritage (Colao et al 2005)
216 Conservation history
Wall paintings are an integral part of monuments and sites and should be preserved
in situ Many of the problems affecting wall paintings are linked to the poor condition of
the building or structure its improper use lack of maintenance frequent repairs and
alterations Also frequent restorations unnecessary uncovering and use of inappropriate
methods and materials can result in irreparable damage Substandard and inadequate
practices and professional qualifications have led to unfortunate results It is for this reason
that an appropriate document covering the principles of proper conservation-restoration of
wall paintings is necessary
The Venice Charter (1964) has provided general principles for the conservation-
restoration of cultural heritage The Amsterdam Declaration (1975) introducing the
concept of integrated conservation and the Nara Document on Authenticity (1994) dealing
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
35 Review of Literature
with cultural diversity have expanded these principles Taking into account these and
additional relevant contributions such as the ICOM-CC Code of Ethics (1984) Document
of Pavia (1997) and ECCO Professional Guidelines (1997) the aim of this document is
to provide more specific principles for the protection preservation and the conservation
restoration of wall paintings This document therefore reflects basic and universally
applicable principles and practices and does not take into account particular problems of
regions or countries which can be supplemented at regional and national level by
providing further recommendations where necessary
217 Preservation techniques of the mural paintings
The removal of fat salts varnishes and pollutants from the surfaces of the works
of art are mostly done by chemical and mechanical methods At the end of the 19th
century the practices of restoration methods that do not inhibit further future interventions
was considered acceptable During the 1960s several chemicals such as polymeric resins
were synthesized and applied as a consolidation or protection agents The accepted idea
was that these substances could be removed at any time leaving a completely unaltered
substrate On the basis of origin archaeological objects can be classified as follows
(Carretti 2005)
1 Inorganic It includes siliceous and nonsiliceous materials Archaeological materials
produced from stones terracotta ceramics and glass can be included under siliceous
materials whereas objects made of metals can be included under nonsiliceous inorganic
materials Again metal objects can be classified as ferrous metals and non-ferrous metals
Objects made of iron are termed as ferrous metal objects whereas metal objects made from
other than iron is termed as non-ferrous metal objects
2 Organic It includes archival and anthropological materials Again archival materials
include paper bhojapatra tadapatra textiles wooden objects miniature paintings whereas
anthropological objects include bone and ivory leather feather and fur etc
In the past restoration of paintings and other old artwork often involved application
of acrylic resins to consolidate and protect them One of the most important tasks for
modern restorers is thus to remove these layers because it turns out that acrylic resins not
only by drastically changing the optics of the treated artwork but in many cases they
accelerate their degradation The scientists use an oil-in-water microemulsion with the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
36 Review of Literature
organic solvent para-xylene as the oil component The matrix makes the cleaning agent
viscous so that it cannot enter very far into the pores of a painting (Carretti 2005)
Nanoparticle treatment is the logical evolution of the Ferroni-Dini method
Dispersions of kinetically stable Ca (OH)2 nanoparticles in non-aqueous solvents solved
most of the drawbacks of the microsized powders Stable dispersions of calcium hydroxide
have been successfully applied (replacing polymers) as fixatives to re-adhere lifted paint
layers during many restoration workshops in Italy and in Europe as a consolidant The
FerronindashDini method (two steps the application of a saturated solution of ammonium
carbonate (NH4)2CO3 and the treatment with a barium hydroxide solution Ba(OH)2 also
called the barium method has long been the acknowledged method for the removal of
salts that threaten paintings reinforcing at the same time the porous structure However
commercially available carbonates and hydroxide powders have dimensions of several
micrometres much larger than the pores on the paint surface This means they donrsquot
penetrate the painting well and there is also a risk of damaging the artwork by a white
glaze forming on the surface (Berger 2006) Restoration should provide the reinforcement
of the porous structure and the consolidation of the surface layer of arte facts A few
simple principles can be considered to define the most appropriate restoration method
1) The treatment should be reversible so that one can revert to the original status of the
work of art at any desired time
2) All the applied chemicals must ensure the maximum durability and the chemical
inertness
3) The applied chemicals must invert the degradation processes without altering the
chemical composition of the artefacts and their physico-chemical and mechanical
properties (Baglioni 2006)
218 Commercial preservative used for preservation of mural paintings
Cleaning was done using soft brushes vacuum cleaner and Gumma paine (dough)
a natural latex sponge Areas near the window were very dirty with black soot and were
cleaned with micro fibrous cloths moistened with synperonic N (surfactant alkyl phenol
ethoxylate based on nonyl phenol) and neutralized with clean water In several places the
paint layers had separated from the substrate (exfoli-ation) In that cases loose paint flakes
were stuck back using Paraloid B72 (10 solution in ethanol) as sparingly as possible
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
37 Review of Literature
Paraloid was injected with syringe behind the exfoliated area twice pushed and held back
with Melinex (polyester film) until fixed on the third application (Bionda et al 2002)
In a period of significant growth of molds and intensive efforts to stop the mold
contamination some of the lines of certain paintings were obscured or faded Solutions of
ethanol formalin 91 and Thiabendazole (TBZ) were used but they were not very
effective Para-formaldehyde fumigation was adopted beginning in 1981 to establish an
emergency treatment sensitivity of microorganisms from studied samples was tested
against Desogen by adding 1-3 (v v) in serial dilutions The best concentration
3 (vv) was applied with a brush to prevent spreading of the spores In order to overcome
the problem of fungal attack suitable fungicides carbendizeme or kiroxy-I or 5 solute of
N formaldehyde can be used Shellac solution in spirit or 2 solution of polyvinaycletate
in toluene can be used as preservative and consolidantsTo control insect and fungal attack
fumigants like pyrethrum DDT or 5 solution of sodium penta chlorophenate in kerosene
oil 2 to 5 solution of PVA in toluene or 2 to 5 solution of paraloid B-72 in toluene or
acetone be used (Miura 2009) Microclimatic conditions constitute a critical factor in the
conservation of cave paintings The unstable microclimatic condition is one of the factors
that always affect the state of conservation of mural paintings In the environmental-
monument system knowledge of the functional environment and climatic conditions of the
surroundings are necessary for the identification of causes of decay (Singh 2011)
Furthermore the risk of formation of indoor bioaerosols in residential and public
buildings (offices schools museums etc) has attracted interest in the last years due to
socio-economic as well as sanitary reasons (Ripka 2005) Thus it is important in aspects of
health and maintenance of Cultural Heritage to analyse the complete microflora to further
develop biocides for harmful microorganisms and methods for restoration of damaged
objects of art The biocidal testing was carried out on one representative algal species of
the two classes of algae viz Chlorococcum sp (green) and Chroococcus sp (blue-green)
found to be common in all the samples Efficiency tests were carried out both in liquid as
well as solid media containing algal suspensions by adding a biocide solution of known
concentration and determining the growth of the microorganism after the incubation
period The biocides used for the past studies were
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
15 Review of Literature
Figure-210 Painting of Raja woodeyar era
Kerala mural paintings are the frescos depicting mythology and legends which are
drawn on the walls of temples and churches in South India principally in Kerala Ancient
temples churches and palaces in Kerala South India display an abounding tradition of
mural paintings mostly dating back between the 9th to 12th centuries The murals of
Thirunadhikkara Cave Temple (now ceded to Tamilnadu) and Tiruvanchikulam are
considered the oldest relics of Keralarsquos own style of murals Fine mural paintings are
depicted in temples at Trikodithanam Ettumanur Vaikom Pundarikapuram
Udayanapuram Triprangode Guruvayoor Kumaranalloor Aymanam the Vadakkunathan
temple in Trichur and the Sri Padmanabhaswamy temple at Thiruvananthapuram Other
mural sites are in the churches at Edappally Vechur Cheppad and Mulanthuruthy and at
palaces such as the Krishnapuram Palace near Kayamkulam and the Padmanabhapuram
Palace
Figure-211 Kerala murals
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
16 Review of Literature
Figure-212 Murals paintings of Kerala temples
There are wall paintings in Badami in the Bijapur district Karnataka Some
excellent paintings exist in the Jain caves at Sitanavassal in Puddukkottai District of Tamil
Nadu Tamil Nadu gave exuberant and glorious expression to themes relating to Siva in the
temples of Panamalai and Kailashanatar in Kancheepuram In the 9th century Jain cave of
Sittannavasal in Tamil Nadu there is a marvellous lotus pond painted on the ceiling In
the heart of the Brihadeeswara temple in Thanjavur Tamil Nadu protected by massive
walls of stone are the finest paintings of the theme of Siva ever painted towards the end of
the 10th century (Sivaramamurthi 1992)
Figure-213 Kancheepuram Mural paintings
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
17 Review of Literature
Figure-214 Sculpture of Mahabalipuram
26 Methods of mural painting
In the history of mural several methods have been used The Buon fresco technique
consists of painting in pigment mixed with water on a thin layer of wet fresh lime mortar
or plaster The pigment is then absorbed by the wet plaster after a number of hours the
plaster dries and reacts with the air it is this chemical reaction which fixes the pigment
particles in the plaster After this the painting stays for a long time up to centuries in fresh
and brilliant colors A Secco painting is done on dry plaster The pigments thus require a
binding medium such as egg (tempera) glue or oil to attach the pigment to the wall
Mezzo-fresco is painted on nearly-dry plaster which is defined by the sixteenth-century
author Ignazio Pozzo as ldquofirm enough not to take a thumb-printrdquo so that the pigment only
penetrates slightly into the plaster Ancestral Hopi village archaeologists found that
fourteen kivas had painted murals and multiple layers of murals on the walls some with up
to twenty-seven layers of murals (Saturno 2006)
The colors used in painting are generally obtained from plants and minerals
Among them only such colors which are lime resistant are suitable for mural painting The
selection of proper colors for a mural painting is an important part of the work as the
longevity the painting depends on it Only mineral colors are preserved for a long time
which could be the reason for use of those colors in early days As per ldquoShilpa ratnardquo and
ldquoAgnipuranardquo the colors used in mural painting are white black red yellow blue and
green Yellow and red are from yellow ochre and red ochre Blue is generally indigo or
china blue White is the prepared wall and black is the carbon soot Mural paintings have
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
18 Review of Literature
survived centuries only on account of the identification and use of those colors which does
not have any reaction with lime (Miraseth 2006)
Originally three types of brushes were made and used flat medium and fine Flat
brushes were made from hairs behind calfrsquos ear the medium from the bottom of goats
belly and the fine brush from delicate blades of grass However in due course of time and
change use of easily available brushes from commercial market and shading of the
original colours can be distinctively noticed The use of blue colour is also noticed over the
passage of time The paintings have been brought down from the walls to plywood cloth
paper and other frames for easy to make and use purposes (Chakarabarti 1980)
27 Themes of mural painting
The subjects and themes in the murals are centered on the Hindu pantheon of Gods
and Goddesses drawn from description in the invocatory verses or Dhyana Slokas More
common representations are of Vishnu in different incarnations Ganesha and
manifestations of Siva We see murals in the Pallimanna Siva Temple devoted to Siva-
Parvatirsquos marriage the Ramayana Story being narrated on the walls of the Mattancheri
palace in the Sankara Narayana the Mahabharata is retold Murals are various scenes from
the Hindu epics and also the frolics of Lord Krishna
It would be interesting to bring into account the influence of the mural paintings on
Christianity On various churches like the St Georgersquos Orthodox Church has Christian
murals bringing out biblical characters and narrating stories from the scriptures Mar
Sabore and Afroth Church at Akapparambu in the outskirts of Ernakulam also have murals
of scenes from the bible Interestingly StMaryrsquos Church at Kanjoor has on both sides of its
entrance a battle scene between the armies of Tipu Sultan and of the English East India
Company It is also apparent that the history of Kerala Murals has its origin in the temple
walls and thus a study of Kerala Murals is not complete without pondering on the
architecture of Kerala its association with the murals (Warrier 2011)
28 Technique used in mural paintings
Indian murals executed on walls of caves structural temples walls of palaces were
based on highly developed techniques Mural painting is a composite structure of these
three basic layers the support the ground and the pigment layer In case of wall painting
the wall itself is the support This is followed by the layer or layers of plaster which
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
19 Review of Literature
constitute the ground The pigment layer is the one which contains the picture The support
is the wall which may be rock surface in a cave or a structural one These stone surfaces
which serve as carriers are rough or uneven This unevenness is itself an advantage as it
provides ldquotoothrdquo to hold the plaster on the surface The uneven surface of the wall has to be
made uniform with layers of plaster in successive gradation of fineness There is generally
one layer of rough plaster followed by one or more layers of fine plaster Ground or plaster
is a term used to mean the surface material of a wall or building which is applied as a
plastic mass made by mixing certain materials with water letting the mass set by drying
carbonation or hydration The active or setting components of plaster are commonly clay
which sets by drying lime which sets by carbonation gypsum and pozzolana which sets by
hydration (Mini 2010)
There are different mixtures for rough plaster In all the mixtures clay limestone
lime and shells in powdered form serve as the matrix The particles of which are held
together by the organic materials like gum glue extracts from barks etc are in fact
adhesives The fine plaster layer requires more careful preparation because it is the layer on
which the pigments are laid to make the picture ldquoShilparatnardquo suggest a mixture of conch
Oyster shells or white clay with gum of neem or slaked lime and coconut water Here the
consolidation is effected by the carbonation of slaked lime ie it absorbs carbon dioxide
from air and becomes carbonate Mural paintings were lime-washed from the 17th until the
beginning of 19th century A few paintings in vaults were never lime-washed for example
at Taby and Floda painted by the medieval painter Albertus Pictor (Mini 2010)
All the paintings have certain basic common characteristics There has to be a wall
or rock surface called support over which the artist goes to work A plaster base called
ground of varied thickness is laid on the support The ground may consist of one or more
layers The strength and life of the whole mural depended up on this ground over which the
painting was done It is the process of applying the final painting on the ground determines
the character of the mural whether it is fresco or tempera The mural painting is done
usually by creating wall surface free of any previous oil or paint by using solvent or by
sand blasting The brick wall is first plastered with mixture of lime and sand in the ratio of
12 A mixture of egg yolk vinegar oil colour is used in dry plaster
There are at least six stages before a Kerala Mural Painting is complete Lekhya
Karma is the first stage where sketching by pencil or crayon is done The second stage is
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
20 Review of Literature
the Rekha Karma which enhances the outlines of the sketching done The third stage called
Varna Karma breathes life into the painting with its colours Here all colours are
appropriately filled in The colouring of the human figures is done according to the
characters and their common virtues The divine and noble characters (Saatvik) are painted
in green those inclined towards power and wealth (Raajasik) is painted in shades of red
lowly mean characters (Tamasik) in white and demons in black In the fourth stage or the
Vartana Karma shading is done Fifth stage called the Lekha Karma brings us to the final
outline of the painting which is usually in black The final and the finishing touches stage
are called Devika Karma (Warrier 2011)
29 Dyes used in mural painting
Indians have been considered as fore runners in the art of natural dyeing Natural
dyes find use in the colouring of textiles drugs cosmetics etc Owing to their non-toxic
effects they are also used for colouring various food products In India there are more
than 450 plants that can yield dyes In addition to their dye-yielding characteristics some
of these plants also possess medicinal value Though there is a large plant resource base
little has been exploited so far Due to lack of availability of precise technical knowledge
on the extracting and dyeing technique it has not commercially succeeded like the
synthetic dyes (Siva 2007)
The color materials on the mural paintings in ancient India were derived from the
natural materials like terracotta chalk red ochre and yellow ochre mixed with animal fat
The dyes for painting is prepared such as white from lime Black from carbon soot of
lamps Red and yellow from minerals Blue from indigo ferra Deep red from lac A fine
coating of resin is done after the painting in order to make a shining appearance Egg yolk
and vinegar was mixed with oil colors and painted on dry plaster (Krishnakumar 1999)
Although plants exhibit a wide range of colours not all of these pigments can be
used as dyes Some do not dissolve in water some cannot be adsorbed onto fibres whereas
others fade when washed or exposed to air or sunlight It remains a mystery why plants
reward us with vibrant dyes India has a rich biodiversity and it is not only one of the
worldrsquos twelve mega diversity countries but also one of the eight major centres of origin
and diversification of domesticated taxa It has approximately 490000 plant species of
which about 17500 are angiosperms more than 400 are domesticated crop species and
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
21 Review of Literature
almost an equal number their wild relatives Thus India harbours a wealth of useful
germplasm resources and there is no doubt that the plant kingdom is a treasure-house of
diverse natural products One such product from nature is the dye (Siva 2007)
Many natural dyestuff and stains were obtained mainly from plants and dominated
as sources of natural dyes producing different colours like red yellow blue black brown
and a combination of these Almost all parts of the plants like root bark leaf fruit wood
seed flower etc produce dyes It is interesting to note that over 2000 pigments are
synthesized by various parts of plants of which only about 150 have been commercially
exploited Nearly 450 taxa are known to yield dyes in India alone of which 50 are
considered to be the most important ten of these are from roots four from barks five from
leaves seven from flowers seven from fruits three from seeds eight from wood and three
from gums and resins Some important dye-yielding plant habitats their distribution and
colouring pigment (Siva 2007)
The dye is generally prepared by boiling the crushed powder with water but
sometimes it is left to steep in cold water The solution then obtained is used generally to
dye coarse cotton fabrics Alum is generally used as a mordant Flowers of Butea
monosperma (Lam) Taubert yield an orange-coloured dye which is not fast and is easily
washed away For the purpose of colouring the material is steeped in a hot or cold
decoction of the flowers A more permanent colour is produced either by first preparing the
cloth with alum and wood ash or by adding these substances to the dye-bath The dye
indigo is produced by steeping the plant in water and allowing it to ferment This is
followed by oxidation of the solution with air in a separate vessel Mallotus philippinensis
muell yields an orange colour used for dyeing silk and wool To prepare the annatto dye
from B orellena the fruits are collected when nearly ripe The seeds and pulp are removed
from the mature fruit and macerated with water Thereafter they are either ground up into
an lsquoannatto pastersquo or dried and marketed as annatto seeds Sometimes when the seeds and
pulp are macerated with water the product is stained through a sieve and the colouring
matter which settles out is collected and partially evaporated by heat and finally dried in
the sun (Sowbhagya 2002)
The predominant colors used in rock art and cave art are black (from charcoal soot
or manganese oxide) yellow ochre (limonite) red ochre (hematite or baked limonite) and
white (kaolin clay burnt shells powdered gypsum or powdered calcium carbonate) All of
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
22 Review of Literature
theses pigments may be used on leather or raw hide as well Early cave art in Seminole
Canyon was monochromatic in red and as culture grew more sophisticated the color
palette expanded Blue Orange Brown Green and Purple are the most common colours
used in Ajantha murals White Pink Gold are occasionally represented mineral earths
containing ferric oxide and copper carbonates were used as source of red yellow and green
colours There is also evidence to establish that root of Rubia cardifolia and leaves of
Indigofera tinctoria were used as source for red and blue colours (Nayer et al 1999)
Many colors of pigments were obtained from both organic and inorganic sources in
ancient times and used to paint various surfaces such as braintan leather clothing and
accoutrements rawhide the human body etc Blue color was obtained from powdered
azurite and lapis duck manure and certain clays Fine Blue-green clay was obtained from
deposits near Mankato Michigan Organic sources of blue include Turkeys Tail a
greenish blue polypore that grows on dead decaying wood (not tannish ones) Native
Americans get Indigo from either Guatemala or Ecuador which was traded well up onto
Kansas long before the Spanish ever set foot here American Indigo has purple tones to it
but IndianJapanese indigo has green tones Berries and crushed flowers were also used to
obtain blue color by rubbing the plant material directly on the leather
An organic source of red was Cochineal It was native west of the Mississippi and
is produced from the bodies of small insects that grow on the prickly pear cactus Ladys
Bedstraw gives a good vermillion red color Harvest the roots dry them out clean the mud
etc off of them and then grind the roots really fine then soak them to extract the red
coloring The key here is drying the root first Blood was also used as red pigment Pucoon
roots also yield a red pigment (Smith 2002) Red ochre the reverse original red colours are
due to variations in iron oxide (or) calcite content and to redox conditions in the firing
produced Brown coloured ceramics owe their colour to maghemite and must be
considered as a fabrication defect due to the position of the ceramic piece in a zone where a
reducing atmosphere prevailed in the course of firingRed pigments were produced from
iron oxides like hematite or limonite and from ochre Hematite was the most frequently
used mineral It occurs in the form of aggregates of small red crystals or in the form of
bigger black crystals which are difficult to crush white was obtained mostly from
kaolinite or illite (Clottes et al 1990)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
23 Review of Literature
210 Biodetoriation of mural paintings
Historic items often contain natural biodegradable materials and have histories of
exposure to moist conditions These two conditions make them amenable to microbial
attack Microbial colonization may damage the building or the cultural asset
(Salonen 2001) Biodeteriogens are organisms involved in deterioration of artifacts They
are very specific for each type of artifact in accordance with its chemical structure and
environment They also have different nutritional requirements and act directly or
indirectly on the substrate The adhesion of microorganisms to a substrate is the result of
cell hydrophobicity and of excreted polymeric substances contained by sheaths capsules
and slimes (Colao 2005)
The surviving wall paintings and decorations in subterranean environments around
Malta are rather scarce (Buhagiar 1986 1993 1998) These include those at St Paulrsquos
Catacombs (Zammit 2008) St Agatharsquos Crypt and Catacombs (Camilleri 2001)
San Catald Catacombs Tac-Cghaqi Abbatija tad-Dejr (Buhagiar 1993) all in Rabat the
cave-sanctuary in Mellieħa (Buhagiar 1987) and the Ħal Saflieni Hypogeum in Paola
(Pace 2000) Previous studies conducted on wall paintings and decorations in Maltese
Palaeo-Christian Catacombs have involved their manufacturing techniques (Muscat 2005)
However to date limited systematic studies have been conducted into the biodeterioration
in Maltese Palaeo- Christian Catacombs The only such studies ever conducted in Malta
concerned the biodeterioration of works of art in catacombs have been carried out at St
Agatharsquos Crypt and Catacombs in Rabat (Zammit et al 2008 Psaila 2006)
Microorganisms can be responsible for the destruction of monuments buildings
and cultural heritage assets including the decay of concrete cement stones mural
paintings etc These microorganisms are not only related with biodeterioration but water-
damaged indoor building materials are frequently colonized by complex bacterial
communities and may emit mixed bioaerosols into the indoor air (Jimenez 2000) It is
well known that mural paintings are colonized by micro-organisms and can be severely
damaged by such growths (Ciferri 1999) A large number of fungal (gt50) and bacterial
taxa (70) have been detected in indoor environments Over 50 bacterial species and 14
genera novel to science were reported in the past 10 years from indoor air and historic
items indicating bacterigravea in these enviroments are as yet only fragmentarily known
(Salonen 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
24 Review of Literature
Traditionally the study of microflora which causes this biodeterioration was based
on classical cultivation methods that were mainly useful to study the physiological
potential of microorganisms but do not provide information on all microbial communities
to be found in excavated artifacts Indeed many studies using culture-independent
techniques which cultivate microorganisms from different environments may often
represent only minor components of the microbial community as a whole It is generally
accepted that cultivation methods recover less than 1 of the total microorganisms present
in environmental samples (Ward et al 1990 Amann et al 1995) Hence microbial
investigations based only on cultivation strategies cannot be regarded as reliable in terms
of reflecting the microbial diversity present in objects of art (Osburn et al 2011)
Early workers suggested that the presence of living microorganisms on stone
increased its susceptibility to damage through their water-binding capacity It has recently
been reported that the mineralogy porosity surface roughness and capacity to collect
water and organic materials control its bioreceptivity and tendency to biodeterioration
(Diakumaku 1995) In addition environmental factors as temperature light pH and
relative humidity affect the number and type of colonising species (Tiano et al 1995) and
hence the progress of colonisation Biofilms on decayed stones consist on mixed microbial
populations embedded in a polymeric matrix Fungi algae filamentous and unicellular
bacteria are found in these complex communities A variety of bacteria have been isolated
from different stone samples confirming the dominance of Gram-positive organisms
especially spore-forming bacteria such as Bacillus and filamentous actinomycetes
(Ripka 2005)
In cultivation studies of deteriorated mural and rock paintings bacterial isolates
have frequently been attributed to the genus Bacillus (Weirich 1989 Tate and Rebrikova
1991 Gonzalez et al 1999 Heyrman et al 1999 Jimenez et al 2000) Other studies that
have included DNA-based techniques to characterize the bacterial community involved in
biodeterioration have shown that a substantial part of the bacterial population is made up of
so far unknown species (Altenburger et al 1996 Rolleke et al 1996 Gurtner et al 2000
Heyrman and Swings 2001) (Heymann et al 2003)
Many potential mycotoxin producers have been detected in air and items from
indoor environments with histories of exposure to moisture for example species of
Acremonium Alternaria Aspergillus Chateomium Fusarium Eurotium Paecilomyces
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
25 Review of Literature
Penicillium Scopulariopsis Stachybotrys Trichoderma Verticillium and Wallemia
(Peltola et al 2001 Pieckova et al 2001) Not all strains of one species produce
mycotoxins and different strains may produce different toxins Whereas toxin producing
strains are frequent in crops and outdoor vegetation toxin producing isolates from indoor
environments and non living assets have only been reported of the species Aspergillus
versicolor (Nielsen et al 1998) Stachybotrys chartarum Nikulin (1997) and
Trichoderma harzianum (Peltola et al 2001) Streptomyces griseus strains producing
valinomycin occur in environments where humans can get exposed
(Andersson et al 2002) The biological properties and toxicity mechanisms of cereulide
were identical to those by valinomycin (Mikkola et al 1999 Salonen et al 2001)
The genus Paenibacillus was first proposed by Ash et al (1993) and its description
was emended by Shida et al (1997) The genus Paenibacillus is under intensive taxonomic
investigation with ten species having been formally described in the last year Heyrman amp
Swings (2001) isolated a strain originally classified as Paenibacillus sp LMG 19508
from biodeteriorated mural paintings in the Servilia tomb at the Roman necropolis of
Carmona in Seville Spain (Smerda et al 2006) Building stone and wall paintings contain
a variety of hydroscopic salts including carbonates chlorides nitrates sulfates etc
dispersed within the porous material or locally concentrated These salts are solubilised
and migrate with the water in and out of the stone Due to changes in physical parameters
the so called salt efflorescences appear on the surfaces providing extremely saline
environments and building niches for settlement of halophilic microorganisms Halite and
other hygroscopic salts can retain considerable quantities of moisture when entrapped in
the building materials and thus favouring the bacterial growth (Ripka 2005)
It is demonstrated that water-damaged indoor building materials contained
substances of microbial origin extremely toxic to eukaryotic cells and large quantities of
several microbial species known to be potentially toxic or immunopotentiating These
include peptidoglycans Gram-negative endotoxin β-13-D glucans lipoglycans and
teichoic acids and mycotoxins (Jimenez 2000) In turn these microorganisms can mediate
the crystallization process These crystallizations can produce destructive effects Some
salts may crystallize or recrystallize to different hydrates which occupy a larger space and
exert additional pressure producing cracking powdering and flaking
(Jimenez and Laiz 2000)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
26 Review of Literature
211 Types of deterioration on mural paintings
The frescos represent a variety of ecological niches where primary colonization is
due to photoautotrophic and chemolithoautotrophic microorganisms followed by
secondary colonization due to heterotrophic bacteria that obtain nutrients from various
sources (metabolites of autotrophic bacteria airborne organic contamination animal faeces
and organic compounds in the paint layers themselves) Microbial-induced deterioration
processes cause structural as well as aesthetic damage to wall paintings such as the
discoloration of materials the formation of crusts on surfaces and the loss of material
(Sarro et al 2006 Osburn et al 2011) Halophilic bacteria and archaea were thought to
be found only in extreme environments like salt lakes or black smokers However it has
been shown that mural paintings and stones are a common habitat for extremely salt
tolerant and moderate halophilic (Ripka 2005) Microbial induced deterioration processes
can cause different kinds of alterations such as discolouration of materials the formation of
crusts on surfaces and the loss of material which leads to structural damage (Ripka 2005)
First of all microorganisms can cause severe problems due to the excretion of aggressive
metabolic products such as organic or inorganic acids Secondly material components can
be used as substrates for microbial metabolism Exoenzymes such as cellulases proteases
tannases beta-glucosidase produced by fungi and bacteria are responsible for hydrolysis of
cellulose and proteins Further examples are mechanical processes caused by swelling and
shrinking of slime or mycelia penetrating inside plaster of the painting resulting in loss of
cohesion and detachment of the paint layer (Rolleke 1996 Gurtner et al 2000)
Table-21 Microbial damage on mural paintings (Rolleke 1996)
S No Damage Microbial activity
1 Green brown red grey
surface layers (patinas)
Pigments produced by microorganisms (intra-or
extracellular) as chlorophyll and carotinoids
2 Dislodging of painting layers Use of organic binders as nutrient and energy
source
3 Acid attack of carbonates Acid produced by fungi or bacteria
4 Discolouration of pigments Redox-reactions induced by fungi and
bacteria
5 Loss of paint layer Growth of microorganisms deep into the plaster
6 Hydrolysis of synthetic
polymers Chemoorganotrophic activity of bacteria and fungi
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
27 Review of Literature
Discolorations are caused by excretion of pigments and microbiologically induced
reductionoxidation-processes (Krumbein et al 1990) Degradation of the bindings is
followed by reduction of stability Oxidation of ammonium and reduced sulphur
compounds results in acidification of the environment such as Sulphuric acid and the
variety of organic acids produced by the heterotrophs cause solubilization of calcareous
binding material and chelation of metal ions (Bock et al 1993) It is now well recognised
that wall paintings can be deteriorated by microorganisms (Ciferri 1999)The growth of
microorganisms essentially results in two types of damage aesthetic and structural
Aesthetic damage implies pigment discoloration stains and formation of a biofilm on the
painted surface Structural damage is observed as cracking and disintegration of the paint
layer formation of paint blisters and degradation of support polymers or of glues and
binders resulting in detachment of paint layer from the support The colonization of mural
paintings by bacteria and other microorganisms can have different causes Provided that
favorable environmental conditions occur nutrients for heterotrophic bacteria and fungi
can be available from metabolites of autotrophic bacteria from airborne contamination and
dripping water from animal faeces but also from organic compounds in the paint layer
itself
212 Methods of studying biodeterioration
It is now well recognized that wall paintings may be deteriorated by
microorganisms as established by several studies that linked the observed damage with the
microbial community present as reviewed by Ciferri (1999) Despite this knowledge a
reliable characterization of bacteria associated with such damage is often lacking To
obtain greater insight into the bacterial community involved in biodeterioration of mural
paintings three sites (from the necropolis at Carmona Spain and the Saint-Catherine
chapel of the castle at Herberstein Austria) were sampled In previous studies from these
sites 385 isolates were analysed by fatty acid methyl ester GC and representatives of
different fatty acid clusters were further studied by 16S rRNA gene sequencing
(Heyrman and Swings 2001) Several of these representative strains showed the highest
sequence similarity with members of the genus Arthrobacter (Heyrman et al 2005)
Jimenez and Samson (1981) analysed the microbial flora of a large fresco painted
in the late 1920s in the monastery ldquoSanta Maria de la Rabidardquo (Huelva Spain) exhibiting
two types of deterioration white efflorescence and green-to-black stains
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
28 Review of Literature
Tate and Rebrikova (1990) thought autotrophic nitrifying bacteria to be the first colonisers
of damaged frescoes and building materials in the cathedral of the nativity of the Virgin in
the Pafnutii-Borovskii monastery (Russia) The bulk of research on biodeterioration of
mural paintings has focused on explaining the observed phenomena by analysing the
microflora present Following this approach a precise characterisation of the
microorganisms using a polyphasic approach was never the first goal
Only a few studies included genomic fingerprinting (16S rDNA sequence analysis)
for the characterisation of bacteria associated with damage on mural paintings
[Rolleke (1996) Pinar et al (2001)] Previous studies based on culture-dependent
techniques showed that the flora present on frescos are fungi (predominant species of
Penicillium Aspergillus Cladosporium and Engyodontium) (Guglielminetti et al 1994)
bacteria (predominant species of Bacillus Arthrobacter Micrococcus Streptomyces and
Pseudomonas) (Heyrman et al 1999) cyanobacteria and eukaryotic algae (species of
Nostoc Lyngbya and Chlorophyceae) (Arino et al 1996 Calvo et al 1993) The killing
effect of an antimicrobial agent on a microorganism can be assessed in several ways
(1) Lethal activity may be expressed as the rate of killing by a fixed concentration
of drug under controlled conditions This rate is determined by measuring the number of
viable bacteria at various time intervals The resulting graphic depiction is known as the
time-kill curve Bacterial killing rates are in part dependent on the class of antibiotic and
the concentration of this agent With certain classes of antibiotics (eg aminoglycosides
and fluoroquino-lones) the rate of killing increases with increased drug concentrations up
to a point of maximum effect This is termed concentration-dependent bactericidal activity
In contrast the killing rates of szlig-lactam agents and vancomycin are relatively slow and
continue only as long as the concentrations are in excess of the MIC This rate of killing is
termed time-dependent bactericidal activity
(2) The minimal concentration of drug needed to kill most of the viable organisms
after incubation for a fixed length of time (generally 24 hours) under a given set of
conditions is the most common estimation of bactericidal activity and is known as either
the minimal bactericidal concentration (MBC) or the minimal lethal concentration (MLC)
It will be referred to in this document as the MBC Unfortunately the definition of the
MBC (999 killing of the final inoculum) is somewhat arbitrary and separates the
bacteria into two populations ndash a segrega-tion which might not have biological relevance
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
29 Review of Literature
The determination of the MBC moreover is so subject to methodologic variables that the
clinical relevance of MBCs is nearly impossible to assess particularly for certain pathogen
and drug combinations (eg Staphylococci and beta-lactam agents)
(3) The serum of a patient receiving an antibiotic may be tested against the
infecting microorganism This can be done using time-kill curve methodology (ie serum
bactericidal rate) or using dilution methodology (ie serum bactericidal titer) The
principles of these methods as well as the influence of biological and technical factors are
similar (Barry et al 1999)
213 Microbial flora associated with deteriorated mural paintings
A great deal of research has been done in this field mainly by using cultivation dependent
methods However by using culture-dependent methods only a very small proportion of
microorganisms can be obtained Far less than 1 of organisms in the environment can be
cultivated by standard cultivation techniques (Pace 1996) Recent studies have shown that
culture-dependent techniques yielded mainly sporeforming bacteria suggesting that plating
leads to an over estimation of the number of spore-forming bacteria A wide number of
investigations have shown that in addition to chemical and physical processes
microorganisms play a major role in degradation of objects of art such as paintings stone-
works wood paper masonry leather parchment glass and metal (Ripka 2005)
A) Bacteria
In general growth of diverse organisms on mural paintings is supported by
humidity slight alkaline pH values and the presence of organic and inorganic nutrient
sources (Weirich 1989) In mural paintings pigments are suspended in water or oil often
binders such as casein and milk are used and they are supplied on the damp lime plaster
(Ciferri 1999) The calcium carbonate formed on contact with air consolidates the
pigments Thus frescos contain mainly inorganic components While chemoautotrophic
nitrifiers and thiobacilli obtain their energy for growth by oxidizing ammonium and
reducing sulphur-compounds respectively heterotrophic bacteria and fungi depend on
organically bound carbon [Tate et al (1991) Lazar (1971) Petushkova et al (1986)
Jimenez et al (1981)] Thus primary colonization of photoautotrophic Cyanobacteria
chemolithoautotrophic nitrifying bacteria and sulphuric acid producing thiobacilli represent
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
30 Review of Literature
the first supply of organic matter The death and lysis of such bacteria promotes the
secondary settlement of heterotrophic bacteria and fungal populations (Calvo et al 1991)
Bacteria may derive from plants or pollen as many sequences obtained in this study
gave high score similarities with bacteria isolated from plants like Moraxella osloensis
Enterobacter cloace Enterobacter agglomerans and Pantoea endophytica Bacteria may
also derive from animal faeces like flies Bacillus Pseudomonas Aeromonas and Panteoa
(Ripka 2005) As Lazar and Dumitru (1973) reported studying mural paintings in a
Romanian monastery the genera Bacillus Arthrobacter and Pseudomonas have been
proved to produce salt efflorescences and were even considered to cause the blanching
phenomenon of frescoes (Jimenez et al 2000) Predominant bacterial genera are Bacillus
Streptomyces Arthrobacter Micrococcus and Pseudomonas [Weirich (1989)
Tate et al (1990) Arroyo et al (1997) Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
B) Fungi
It may be concluded that there is wide variety of fungal forms present on mural
paintings but Aspergillus and Alternaria were found dominating from all the experimental
sites next to them were Cladosporium Drechestera Fusarium Curvularia Chaetomium
Memnoniella Mycelia sterelai Pencillium Emericella Stachybotrytis Trichoderma
Phoma Monodictys Humicola and Epicoccum (Garg et al 1995)
The fungal genera most commonly found in lists of isolated taxa given in literature
are Alternaria Aspergillus Chaetomium Cladosporium Fusarium Penicillium and
Verticullum [Weirich (1989) Tate et al (1990) Guglielminetti et al (1994)
Garg et al (1995) Berner et al (1997) Ciferri (1999)] Some fungi having hard fruiting
bodies represented by sclerotia pycnidia perithecia cleistothecia and stroma could
organize themselves inside the painted layer Many fungal forms having such structures
were identified from our experimental sites viz Emericella nidulans A flavus
Chaetomium sp and Phoma sp etc These structures with little increase in humidity may
cause swelling in the paint film (Garg 1995)
Strains of species of Alternaria and Cladosporium both of them identified on the
mural paintings of the Palace of Schoumlnbrunn are the most common genera isolated from
stone and mural paintings in indoor environments with standard cultivation methods
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
31 Review of Literature
(Ventosa 2004) Saprophytic species of the genus Cladosporium are among the most
abundant fungi isolated in saltern samples Commonly isolated Cyanobacteria belong to
Nostoc and eukaryotic algae to Lyngbya and members of the Chlorophyceae such as
Chlorella Pseudococcomyxa and Pseudopleurococcus [Gorbushina et al (1987)
Calvo et al (1993) Arino et al (1996)]
They grow optimally on media with low water activity due to high salt or sugar
concentrations seem to propagate 70 vegetatively in the salterns and are thus
halotolerantosmotolerant species rather than simple flush-through occurrences
Cladiosporum herbarum was frequently isolated from hypersaline waters dead and dying
plant material air soil food fruit cereals paint and textiles (Ventosa 2004)
C) Algae
Most of the painted areas in temperature climate became covered with green algae
(Pleurococcus Protococcus and Trentopholia) while under tropical conditions blue green
algae of the genera Oscillatoria and Sytonema predominated (Garg 1995) The main
factors which contribute to the growth of algae on wall paintings are the presence of
moisture in the plaster as well as availability of visible light These conditions are quite
prevalent in the tropical climate but in temperature regions also algal growth on wall
paintings have been reported [Tonolo et al (1961) Pietrini et al (1991)]
D) Actinomycetes
Usually literature refers to specific aspects eg the occurrence of cyanobacteria
and algae in caves with natural openings to sunlight or those with artificial lighting fungi
and so forth Actinomycetes have been considered to be mainly confined to soils where
they find their natural habitat but despite intensive studies there are still many gaps in our
knowledge of the role played by actinomycetes in soil processes and biodegrations of
murals cave paintings (Groth et al 1999) In addition halophilic bacteria actinomycetes
and cyanobacteria are also capable of growing on salt-affected mural paintings
(Karbowska 2003)
Monte and Ferrari (1993) reviewed the mechanisms of biodeterioration in tombs
and underground churches The role of actinomycetes in the deterioration of frescoes in
hypogean environments was stressed by Agarossi et al (1985) Monte and Ferrari (1993)
Giacobini et al (1987) described the serious damage suffered by a whole series of famous
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
32 Review of Literature
frescoes in underground environments Actinomycetes were isolated from these mural
paintings located in crypts caves and tombs About 200 strains of actinomycetes were
isolated 60 of which were identified The most frequent species were Streptomyces albus
S cinereoruber S griseolus S vinaceus and some members of the Nocardia genus
Heterotrophic bacteria and actinomycetes were the most abundant microorganisms
on the frescoes of Etruscan tombs (Agarossi et al 1985) Bettini et al (1977) studied
some of the oldest Etruscan tombs (7th to 4th century BC) and found white-grey patinas
and spots from streptomycetes in the mural paintings They related the biodeterioration to
the microclimatic conditions (eg lower temperatures high RH) Monte and Ferrari (1993)
considered that colonization of the mural paintings was the result of selective competitive
and inhibitory dynamics among different microorganisms under different and changing
environmental conditions The pigments excreted by some actinomycetes were responsible
for the violet stains found on the walls of tombs in Tarquinia Similar stains were observed
in one of the Roman tombs the Circular Mausoleum the Necropolis of Carmona Spain
from which a Streptomyces sp producing violet pigments in culture media was isolated
214 Identification of biodeteriogens
The possibility of pigments and biodeteriogens identification in frescos and stone
monitoring is offered mostly by vibrational spectroscopy infrared thermography laser
induced fluorescence (LIF) laser induced breakdown spectroscopy (LIBS) XRF (X-Ray
Fluorescence) IR and UV emission Among them laser based methods allowing for in
situ or remote characterization of artwork surface were applied successfully for
prospecting diagnosis and maintenance (Colao et al 2005) The rep-PCR fingerprinting
of the isolates allowed determination of their genotypic diversity Studies that have
compared rep-PCR genomic fingerprint analysis with DNAndashDNA relatedness studies have
shown that the two techniques yield results that are in close agreement [Nick et al (1999)
Rademaker et al (2000)] These studies therefore suggest that rep-PCR fingerprinting can
be used as a genomic screening method to differentiate at the species level and to select
representatives for DNAndashDNA reassociation experiments (Heymann et al 2003)
The characterisation of bacteria was for example often limited to isolation from
group-specific media followed by microscopy [Sorlini et al (1987) Weirich (1989)
Tate et al (1990) and in more recent studies to morphological and physiological
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
33 Review of Literature
characteristics including miniaturised and automated systems such as API and BIOLOG
[Arroyo et al (1997) Jimmenez et al (2000) and Laiz et al (2000)] or to
chemotaxonomic characteristics [Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
Wagner et al (1994) demonstrated that conventional microbiological efforts can
fail to isolate all microorganisms present in natural samples DNA-based techniques used
to identify microorganisms have revealed only a smaller fraction of bacteria isolated from
artworks (Ward et al 1990 Rolleke et al 1996) Bacterial identification using molecular
techniques especially those including the sequencing of genes coding for ribosomal
16S rRNA is very important to study bacterial communities found on artefacts One such
method is Denaturing Gradient Gel Electrophoresis (DGGE) of PCR-amplified gene
fragments coding for rRNA (Muyzer et al 1993) that allows the separation of partial
16S rDNA amplified fragments of identical length but different sequence due to their
different melting behaviour in a gel system containing a gradient of denaturants
(Jimenez 2003)
Total genomic DNA was purified for 16S rRNA gene sequencing and rep-PCR
using a slight modification of the method of Pitcher et al (1989) as described by
Heyndrickx et al (1996) rep-PCR genomic fingerprinting was performed with the REP-
and (GTG)5 primers (Versalovic et al 1994) using the PCR conditions described
previously by Rademaker et al (1997) Electrophoresis and pattern analysis were further
performed as described by Heyrman et al (2003) 16S rRNA gene sequencing and
phylogenetic analysis were performed as described by Heyrman and Swings (2001)
Phylogenetic trees were constructed using the BioNumerics software (Applied Maths) by
applying the neighbour-joining and maximum-parsimony methods on a multiple alignment
similarity matrix The stability of relationships was assessed by a bootstrap analysis of
1000 datasets For determination of the G+C content and levels of DNAndashDNA
hybridization approximately 1 g biomass was harvested from agar plates DNA was
purified by using a combination of the protocols of Marmur (1961) and
Pitcher et al (1989) as described by Logan et al (2000) The G+C content of the DNA
was determined by HPLC (Mesbah et al 1989) using the further specifications given by
Logan et al (2000) DNAndashDNA hybridization experiments were performed using a
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
34 Review of Literature
modification of the microplate method of Ezaki et al (1989) as described by
Willems et al (2001)
215 Preservation and conservation
Nowadays the conservation and preservation of our cultural heritage is one of the
world main concerns particularly in Europe The increasing need for non-destructive
investigation tools has become a major issue as sampling is in most cases restricted in
view of the value or the uniqueness of the object Artworks as wall paintings in buildings
and monuments of historical interest are affected by environment physical (temperature
and humidity) and biological factors (biodeteriogens) and by human (pollutant releases)
impact and therefore modified over the time The term ldquoconservationrdquo may have many
different meanings in different fields Every intervention directed to the restoration and
safeguard of works of art is commonly considered as a conservation treatment For
example conservation can involve the cleaning procedures set up by chemists or the photo
documentation of the preservation of historical memory For the appropriate conservation
of works of art even the lighting systems in a museum or the control of the visitorrsquos
movements in a site should be monitored Chemical degradation which induces the flaking
of paintings and deterioration from rain wind dust and other environmental causes is
mainly responsible for the weakening of the porous structure and the surface layers of the
materials used in works of cultural heritage (Colao et al 2005)
216 Conservation history
Wall paintings are an integral part of monuments and sites and should be preserved
in situ Many of the problems affecting wall paintings are linked to the poor condition of
the building or structure its improper use lack of maintenance frequent repairs and
alterations Also frequent restorations unnecessary uncovering and use of inappropriate
methods and materials can result in irreparable damage Substandard and inadequate
practices and professional qualifications have led to unfortunate results It is for this reason
that an appropriate document covering the principles of proper conservation-restoration of
wall paintings is necessary
The Venice Charter (1964) has provided general principles for the conservation-
restoration of cultural heritage The Amsterdam Declaration (1975) introducing the
concept of integrated conservation and the Nara Document on Authenticity (1994) dealing
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
35 Review of Literature
with cultural diversity have expanded these principles Taking into account these and
additional relevant contributions such as the ICOM-CC Code of Ethics (1984) Document
of Pavia (1997) and ECCO Professional Guidelines (1997) the aim of this document is
to provide more specific principles for the protection preservation and the conservation
restoration of wall paintings This document therefore reflects basic and universally
applicable principles and practices and does not take into account particular problems of
regions or countries which can be supplemented at regional and national level by
providing further recommendations where necessary
217 Preservation techniques of the mural paintings
The removal of fat salts varnishes and pollutants from the surfaces of the works
of art are mostly done by chemical and mechanical methods At the end of the 19th
century the practices of restoration methods that do not inhibit further future interventions
was considered acceptable During the 1960s several chemicals such as polymeric resins
were synthesized and applied as a consolidation or protection agents The accepted idea
was that these substances could be removed at any time leaving a completely unaltered
substrate On the basis of origin archaeological objects can be classified as follows
(Carretti 2005)
1 Inorganic It includes siliceous and nonsiliceous materials Archaeological materials
produced from stones terracotta ceramics and glass can be included under siliceous
materials whereas objects made of metals can be included under nonsiliceous inorganic
materials Again metal objects can be classified as ferrous metals and non-ferrous metals
Objects made of iron are termed as ferrous metal objects whereas metal objects made from
other than iron is termed as non-ferrous metal objects
2 Organic It includes archival and anthropological materials Again archival materials
include paper bhojapatra tadapatra textiles wooden objects miniature paintings whereas
anthropological objects include bone and ivory leather feather and fur etc
In the past restoration of paintings and other old artwork often involved application
of acrylic resins to consolidate and protect them One of the most important tasks for
modern restorers is thus to remove these layers because it turns out that acrylic resins not
only by drastically changing the optics of the treated artwork but in many cases they
accelerate their degradation The scientists use an oil-in-water microemulsion with the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
36 Review of Literature
organic solvent para-xylene as the oil component The matrix makes the cleaning agent
viscous so that it cannot enter very far into the pores of a painting (Carretti 2005)
Nanoparticle treatment is the logical evolution of the Ferroni-Dini method
Dispersions of kinetically stable Ca (OH)2 nanoparticles in non-aqueous solvents solved
most of the drawbacks of the microsized powders Stable dispersions of calcium hydroxide
have been successfully applied (replacing polymers) as fixatives to re-adhere lifted paint
layers during many restoration workshops in Italy and in Europe as a consolidant The
FerronindashDini method (two steps the application of a saturated solution of ammonium
carbonate (NH4)2CO3 and the treatment with a barium hydroxide solution Ba(OH)2 also
called the barium method has long been the acknowledged method for the removal of
salts that threaten paintings reinforcing at the same time the porous structure However
commercially available carbonates and hydroxide powders have dimensions of several
micrometres much larger than the pores on the paint surface This means they donrsquot
penetrate the painting well and there is also a risk of damaging the artwork by a white
glaze forming on the surface (Berger 2006) Restoration should provide the reinforcement
of the porous structure and the consolidation of the surface layer of arte facts A few
simple principles can be considered to define the most appropriate restoration method
1) The treatment should be reversible so that one can revert to the original status of the
work of art at any desired time
2) All the applied chemicals must ensure the maximum durability and the chemical
inertness
3) The applied chemicals must invert the degradation processes without altering the
chemical composition of the artefacts and their physico-chemical and mechanical
properties (Baglioni 2006)
218 Commercial preservative used for preservation of mural paintings
Cleaning was done using soft brushes vacuum cleaner and Gumma paine (dough)
a natural latex sponge Areas near the window were very dirty with black soot and were
cleaned with micro fibrous cloths moistened with synperonic N (surfactant alkyl phenol
ethoxylate based on nonyl phenol) and neutralized with clean water In several places the
paint layers had separated from the substrate (exfoli-ation) In that cases loose paint flakes
were stuck back using Paraloid B72 (10 solution in ethanol) as sparingly as possible
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
37 Review of Literature
Paraloid was injected with syringe behind the exfoliated area twice pushed and held back
with Melinex (polyester film) until fixed on the third application (Bionda et al 2002)
In a period of significant growth of molds and intensive efforts to stop the mold
contamination some of the lines of certain paintings were obscured or faded Solutions of
ethanol formalin 91 and Thiabendazole (TBZ) were used but they were not very
effective Para-formaldehyde fumigation was adopted beginning in 1981 to establish an
emergency treatment sensitivity of microorganisms from studied samples was tested
against Desogen by adding 1-3 (v v) in serial dilutions The best concentration
3 (vv) was applied with a brush to prevent spreading of the spores In order to overcome
the problem of fungal attack suitable fungicides carbendizeme or kiroxy-I or 5 solute of
N formaldehyde can be used Shellac solution in spirit or 2 solution of polyvinaycletate
in toluene can be used as preservative and consolidantsTo control insect and fungal attack
fumigants like pyrethrum DDT or 5 solution of sodium penta chlorophenate in kerosene
oil 2 to 5 solution of PVA in toluene or 2 to 5 solution of paraloid B-72 in toluene or
acetone be used (Miura 2009) Microclimatic conditions constitute a critical factor in the
conservation of cave paintings The unstable microclimatic condition is one of the factors
that always affect the state of conservation of mural paintings In the environmental-
monument system knowledge of the functional environment and climatic conditions of the
surroundings are necessary for the identification of causes of decay (Singh 2011)
Furthermore the risk of formation of indoor bioaerosols in residential and public
buildings (offices schools museums etc) has attracted interest in the last years due to
socio-economic as well as sanitary reasons (Ripka 2005) Thus it is important in aspects of
health and maintenance of Cultural Heritage to analyse the complete microflora to further
develop biocides for harmful microorganisms and methods for restoration of damaged
objects of art The biocidal testing was carried out on one representative algal species of
the two classes of algae viz Chlorococcum sp (green) and Chroococcus sp (blue-green)
found to be common in all the samples Efficiency tests were carried out both in liquid as
well as solid media containing algal suspensions by adding a biocide solution of known
concentration and determining the growth of the microorganism after the incubation
period The biocides used for the past studies were
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
16 Review of Literature
Figure-212 Murals paintings of Kerala temples
There are wall paintings in Badami in the Bijapur district Karnataka Some
excellent paintings exist in the Jain caves at Sitanavassal in Puddukkottai District of Tamil
Nadu Tamil Nadu gave exuberant and glorious expression to themes relating to Siva in the
temples of Panamalai and Kailashanatar in Kancheepuram In the 9th century Jain cave of
Sittannavasal in Tamil Nadu there is a marvellous lotus pond painted on the ceiling In
the heart of the Brihadeeswara temple in Thanjavur Tamil Nadu protected by massive
walls of stone are the finest paintings of the theme of Siva ever painted towards the end of
the 10th century (Sivaramamurthi 1992)
Figure-213 Kancheepuram Mural paintings
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
17 Review of Literature
Figure-214 Sculpture of Mahabalipuram
26 Methods of mural painting
In the history of mural several methods have been used The Buon fresco technique
consists of painting in pigment mixed with water on a thin layer of wet fresh lime mortar
or plaster The pigment is then absorbed by the wet plaster after a number of hours the
plaster dries and reacts with the air it is this chemical reaction which fixes the pigment
particles in the plaster After this the painting stays for a long time up to centuries in fresh
and brilliant colors A Secco painting is done on dry plaster The pigments thus require a
binding medium such as egg (tempera) glue or oil to attach the pigment to the wall
Mezzo-fresco is painted on nearly-dry plaster which is defined by the sixteenth-century
author Ignazio Pozzo as ldquofirm enough not to take a thumb-printrdquo so that the pigment only
penetrates slightly into the plaster Ancestral Hopi village archaeologists found that
fourteen kivas had painted murals and multiple layers of murals on the walls some with up
to twenty-seven layers of murals (Saturno 2006)
The colors used in painting are generally obtained from plants and minerals
Among them only such colors which are lime resistant are suitable for mural painting The
selection of proper colors for a mural painting is an important part of the work as the
longevity the painting depends on it Only mineral colors are preserved for a long time
which could be the reason for use of those colors in early days As per ldquoShilpa ratnardquo and
ldquoAgnipuranardquo the colors used in mural painting are white black red yellow blue and
green Yellow and red are from yellow ochre and red ochre Blue is generally indigo or
china blue White is the prepared wall and black is the carbon soot Mural paintings have
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
18 Review of Literature
survived centuries only on account of the identification and use of those colors which does
not have any reaction with lime (Miraseth 2006)
Originally three types of brushes were made and used flat medium and fine Flat
brushes were made from hairs behind calfrsquos ear the medium from the bottom of goats
belly and the fine brush from delicate blades of grass However in due course of time and
change use of easily available brushes from commercial market and shading of the
original colours can be distinctively noticed The use of blue colour is also noticed over the
passage of time The paintings have been brought down from the walls to plywood cloth
paper and other frames for easy to make and use purposes (Chakarabarti 1980)
27 Themes of mural painting
The subjects and themes in the murals are centered on the Hindu pantheon of Gods
and Goddesses drawn from description in the invocatory verses or Dhyana Slokas More
common representations are of Vishnu in different incarnations Ganesha and
manifestations of Siva We see murals in the Pallimanna Siva Temple devoted to Siva-
Parvatirsquos marriage the Ramayana Story being narrated on the walls of the Mattancheri
palace in the Sankara Narayana the Mahabharata is retold Murals are various scenes from
the Hindu epics and also the frolics of Lord Krishna
It would be interesting to bring into account the influence of the mural paintings on
Christianity On various churches like the St Georgersquos Orthodox Church has Christian
murals bringing out biblical characters and narrating stories from the scriptures Mar
Sabore and Afroth Church at Akapparambu in the outskirts of Ernakulam also have murals
of scenes from the bible Interestingly StMaryrsquos Church at Kanjoor has on both sides of its
entrance a battle scene between the armies of Tipu Sultan and of the English East India
Company It is also apparent that the history of Kerala Murals has its origin in the temple
walls and thus a study of Kerala Murals is not complete without pondering on the
architecture of Kerala its association with the murals (Warrier 2011)
28 Technique used in mural paintings
Indian murals executed on walls of caves structural temples walls of palaces were
based on highly developed techniques Mural painting is a composite structure of these
three basic layers the support the ground and the pigment layer In case of wall painting
the wall itself is the support This is followed by the layer or layers of plaster which
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
19 Review of Literature
constitute the ground The pigment layer is the one which contains the picture The support
is the wall which may be rock surface in a cave or a structural one These stone surfaces
which serve as carriers are rough or uneven This unevenness is itself an advantage as it
provides ldquotoothrdquo to hold the plaster on the surface The uneven surface of the wall has to be
made uniform with layers of plaster in successive gradation of fineness There is generally
one layer of rough plaster followed by one or more layers of fine plaster Ground or plaster
is a term used to mean the surface material of a wall or building which is applied as a
plastic mass made by mixing certain materials with water letting the mass set by drying
carbonation or hydration The active or setting components of plaster are commonly clay
which sets by drying lime which sets by carbonation gypsum and pozzolana which sets by
hydration (Mini 2010)
There are different mixtures for rough plaster In all the mixtures clay limestone
lime and shells in powdered form serve as the matrix The particles of which are held
together by the organic materials like gum glue extracts from barks etc are in fact
adhesives The fine plaster layer requires more careful preparation because it is the layer on
which the pigments are laid to make the picture ldquoShilparatnardquo suggest a mixture of conch
Oyster shells or white clay with gum of neem or slaked lime and coconut water Here the
consolidation is effected by the carbonation of slaked lime ie it absorbs carbon dioxide
from air and becomes carbonate Mural paintings were lime-washed from the 17th until the
beginning of 19th century A few paintings in vaults were never lime-washed for example
at Taby and Floda painted by the medieval painter Albertus Pictor (Mini 2010)
All the paintings have certain basic common characteristics There has to be a wall
or rock surface called support over which the artist goes to work A plaster base called
ground of varied thickness is laid on the support The ground may consist of one or more
layers The strength and life of the whole mural depended up on this ground over which the
painting was done It is the process of applying the final painting on the ground determines
the character of the mural whether it is fresco or tempera The mural painting is done
usually by creating wall surface free of any previous oil or paint by using solvent or by
sand blasting The brick wall is first plastered with mixture of lime and sand in the ratio of
12 A mixture of egg yolk vinegar oil colour is used in dry plaster
There are at least six stages before a Kerala Mural Painting is complete Lekhya
Karma is the first stage where sketching by pencil or crayon is done The second stage is
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
20 Review of Literature
the Rekha Karma which enhances the outlines of the sketching done The third stage called
Varna Karma breathes life into the painting with its colours Here all colours are
appropriately filled in The colouring of the human figures is done according to the
characters and their common virtues The divine and noble characters (Saatvik) are painted
in green those inclined towards power and wealth (Raajasik) is painted in shades of red
lowly mean characters (Tamasik) in white and demons in black In the fourth stage or the
Vartana Karma shading is done Fifth stage called the Lekha Karma brings us to the final
outline of the painting which is usually in black The final and the finishing touches stage
are called Devika Karma (Warrier 2011)
29 Dyes used in mural painting
Indians have been considered as fore runners in the art of natural dyeing Natural
dyes find use in the colouring of textiles drugs cosmetics etc Owing to their non-toxic
effects they are also used for colouring various food products In India there are more
than 450 plants that can yield dyes In addition to their dye-yielding characteristics some
of these plants also possess medicinal value Though there is a large plant resource base
little has been exploited so far Due to lack of availability of precise technical knowledge
on the extracting and dyeing technique it has not commercially succeeded like the
synthetic dyes (Siva 2007)
The color materials on the mural paintings in ancient India were derived from the
natural materials like terracotta chalk red ochre and yellow ochre mixed with animal fat
The dyes for painting is prepared such as white from lime Black from carbon soot of
lamps Red and yellow from minerals Blue from indigo ferra Deep red from lac A fine
coating of resin is done after the painting in order to make a shining appearance Egg yolk
and vinegar was mixed with oil colors and painted on dry plaster (Krishnakumar 1999)
Although plants exhibit a wide range of colours not all of these pigments can be
used as dyes Some do not dissolve in water some cannot be adsorbed onto fibres whereas
others fade when washed or exposed to air or sunlight It remains a mystery why plants
reward us with vibrant dyes India has a rich biodiversity and it is not only one of the
worldrsquos twelve mega diversity countries but also one of the eight major centres of origin
and diversification of domesticated taxa It has approximately 490000 plant species of
which about 17500 are angiosperms more than 400 are domesticated crop species and
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
21 Review of Literature
almost an equal number their wild relatives Thus India harbours a wealth of useful
germplasm resources and there is no doubt that the plant kingdom is a treasure-house of
diverse natural products One such product from nature is the dye (Siva 2007)
Many natural dyestuff and stains were obtained mainly from plants and dominated
as sources of natural dyes producing different colours like red yellow blue black brown
and a combination of these Almost all parts of the plants like root bark leaf fruit wood
seed flower etc produce dyes It is interesting to note that over 2000 pigments are
synthesized by various parts of plants of which only about 150 have been commercially
exploited Nearly 450 taxa are known to yield dyes in India alone of which 50 are
considered to be the most important ten of these are from roots four from barks five from
leaves seven from flowers seven from fruits three from seeds eight from wood and three
from gums and resins Some important dye-yielding plant habitats their distribution and
colouring pigment (Siva 2007)
The dye is generally prepared by boiling the crushed powder with water but
sometimes it is left to steep in cold water The solution then obtained is used generally to
dye coarse cotton fabrics Alum is generally used as a mordant Flowers of Butea
monosperma (Lam) Taubert yield an orange-coloured dye which is not fast and is easily
washed away For the purpose of colouring the material is steeped in a hot or cold
decoction of the flowers A more permanent colour is produced either by first preparing the
cloth with alum and wood ash or by adding these substances to the dye-bath The dye
indigo is produced by steeping the plant in water and allowing it to ferment This is
followed by oxidation of the solution with air in a separate vessel Mallotus philippinensis
muell yields an orange colour used for dyeing silk and wool To prepare the annatto dye
from B orellena the fruits are collected when nearly ripe The seeds and pulp are removed
from the mature fruit and macerated with water Thereafter they are either ground up into
an lsquoannatto pastersquo or dried and marketed as annatto seeds Sometimes when the seeds and
pulp are macerated with water the product is stained through a sieve and the colouring
matter which settles out is collected and partially evaporated by heat and finally dried in
the sun (Sowbhagya 2002)
The predominant colors used in rock art and cave art are black (from charcoal soot
or manganese oxide) yellow ochre (limonite) red ochre (hematite or baked limonite) and
white (kaolin clay burnt shells powdered gypsum or powdered calcium carbonate) All of
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
22 Review of Literature
theses pigments may be used on leather or raw hide as well Early cave art in Seminole
Canyon was monochromatic in red and as culture grew more sophisticated the color
palette expanded Blue Orange Brown Green and Purple are the most common colours
used in Ajantha murals White Pink Gold are occasionally represented mineral earths
containing ferric oxide and copper carbonates were used as source of red yellow and green
colours There is also evidence to establish that root of Rubia cardifolia and leaves of
Indigofera tinctoria were used as source for red and blue colours (Nayer et al 1999)
Many colors of pigments were obtained from both organic and inorganic sources in
ancient times and used to paint various surfaces such as braintan leather clothing and
accoutrements rawhide the human body etc Blue color was obtained from powdered
azurite and lapis duck manure and certain clays Fine Blue-green clay was obtained from
deposits near Mankato Michigan Organic sources of blue include Turkeys Tail a
greenish blue polypore that grows on dead decaying wood (not tannish ones) Native
Americans get Indigo from either Guatemala or Ecuador which was traded well up onto
Kansas long before the Spanish ever set foot here American Indigo has purple tones to it
but IndianJapanese indigo has green tones Berries and crushed flowers were also used to
obtain blue color by rubbing the plant material directly on the leather
An organic source of red was Cochineal It was native west of the Mississippi and
is produced from the bodies of small insects that grow on the prickly pear cactus Ladys
Bedstraw gives a good vermillion red color Harvest the roots dry them out clean the mud
etc off of them and then grind the roots really fine then soak them to extract the red
coloring The key here is drying the root first Blood was also used as red pigment Pucoon
roots also yield a red pigment (Smith 2002) Red ochre the reverse original red colours are
due to variations in iron oxide (or) calcite content and to redox conditions in the firing
produced Brown coloured ceramics owe their colour to maghemite and must be
considered as a fabrication defect due to the position of the ceramic piece in a zone where a
reducing atmosphere prevailed in the course of firingRed pigments were produced from
iron oxides like hematite or limonite and from ochre Hematite was the most frequently
used mineral It occurs in the form of aggregates of small red crystals or in the form of
bigger black crystals which are difficult to crush white was obtained mostly from
kaolinite or illite (Clottes et al 1990)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
23 Review of Literature
210 Biodetoriation of mural paintings
Historic items often contain natural biodegradable materials and have histories of
exposure to moist conditions These two conditions make them amenable to microbial
attack Microbial colonization may damage the building or the cultural asset
(Salonen 2001) Biodeteriogens are organisms involved in deterioration of artifacts They
are very specific for each type of artifact in accordance with its chemical structure and
environment They also have different nutritional requirements and act directly or
indirectly on the substrate The adhesion of microorganisms to a substrate is the result of
cell hydrophobicity and of excreted polymeric substances contained by sheaths capsules
and slimes (Colao 2005)
The surviving wall paintings and decorations in subterranean environments around
Malta are rather scarce (Buhagiar 1986 1993 1998) These include those at St Paulrsquos
Catacombs (Zammit 2008) St Agatharsquos Crypt and Catacombs (Camilleri 2001)
San Catald Catacombs Tac-Cghaqi Abbatija tad-Dejr (Buhagiar 1993) all in Rabat the
cave-sanctuary in Mellieħa (Buhagiar 1987) and the Ħal Saflieni Hypogeum in Paola
(Pace 2000) Previous studies conducted on wall paintings and decorations in Maltese
Palaeo-Christian Catacombs have involved their manufacturing techniques (Muscat 2005)
However to date limited systematic studies have been conducted into the biodeterioration
in Maltese Palaeo- Christian Catacombs The only such studies ever conducted in Malta
concerned the biodeterioration of works of art in catacombs have been carried out at St
Agatharsquos Crypt and Catacombs in Rabat (Zammit et al 2008 Psaila 2006)
Microorganisms can be responsible for the destruction of monuments buildings
and cultural heritage assets including the decay of concrete cement stones mural
paintings etc These microorganisms are not only related with biodeterioration but water-
damaged indoor building materials are frequently colonized by complex bacterial
communities and may emit mixed bioaerosols into the indoor air (Jimenez 2000) It is
well known that mural paintings are colonized by micro-organisms and can be severely
damaged by such growths (Ciferri 1999) A large number of fungal (gt50) and bacterial
taxa (70) have been detected in indoor environments Over 50 bacterial species and 14
genera novel to science were reported in the past 10 years from indoor air and historic
items indicating bacterigravea in these enviroments are as yet only fragmentarily known
(Salonen 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
24 Review of Literature
Traditionally the study of microflora which causes this biodeterioration was based
on classical cultivation methods that were mainly useful to study the physiological
potential of microorganisms but do not provide information on all microbial communities
to be found in excavated artifacts Indeed many studies using culture-independent
techniques which cultivate microorganisms from different environments may often
represent only minor components of the microbial community as a whole It is generally
accepted that cultivation methods recover less than 1 of the total microorganisms present
in environmental samples (Ward et al 1990 Amann et al 1995) Hence microbial
investigations based only on cultivation strategies cannot be regarded as reliable in terms
of reflecting the microbial diversity present in objects of art (Osburn et al 2011)
Early workers suggested that the presence of living microorganisms on stone
increased its susceptibility to damage through their water-binding capacity It has recently
been reported that the mineralogy porosity surface roughness and capacity to collect
water and organic materials control its bioreceptivity and tendency to biodeterioration
(Diakumaku 1995) In addition environmental factors as temperature light pH and
relative humidity affect the number and type of colonising species (Tiano et al 1995) and
hence the progress of colonisation Biofilms on decayed stones consist on mixed microbial
populations embedded in a polymeric matrix Fungi algae filamentous and unicellular
bacteria are found in these complex communities A variety of bacteria have been isolated
from different stone samples confirming the dominance of Gram-positive organisms
especially spore-forming bacteria such as Bacillus and filamentous actinomycetes
(Ripka 2005)
In cultivation studies of deteriorated mural and rock paintings bacterial isolates
have frequently been attributed to the genus Bacillus (Weirich 1989 Tate and Rebrikova
1991 Gonzalez et al 1999 Heyrman et al 1999 Jimenez et al 2000) Other studies that
have included DNA-based techniques to characterize the bacterial community involved in
biodeterioration have shown that a substantial part of the bacterial population is made up of
so far unknown species (Altenburger et al 1996 Rolleke et al 1996 Gurtner et al 2000
Heyrman and Swings 2001) (Heymann et al 2003)
Many potential mycotoxin producers have been detected in air and items from
indoor environments with histories of exposure to moisture for example species of
Acremonium Alternaria Aspergillus Chateomium Fusarium Eurotium Paecilomyces
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
25 Review of Literature
Penicillium Scopulariopsis Stachybotrys Trichoderma Verticillium and Wallemia
(Peltola et al 2001 Pieckova et al 2001) Not all strains of one species produce
mycotoxins and different strains may produce different toxins Whereas toxin producing
strains are frequent in crops and outdoor vegetation toxin producing isolates from indoor
environments and non living assets have only been reported of the species Aspergillus
versicolor (Nielsen et al 1998) Stachybotrys chartarum Nikulin (1997) and
Trichoderma harzianum (Peltola et al 2001) Streptomyces griseus strains producing
valinomycin occur in environments where humans can get exposed
(Andersson et al 2002) The biological properties and toxicity mechanisms of cereulide
were identical to those by valinomycin (Mikkola et al 1999 Salonen et al 2001)
The genus Paenibacillus was first proposed by Ash et al (1993) and its description
was emended by Shida et al (1997) The genus Paenibacillus is under intensive taxonomic
investigation with ten species having been formally described in the last year Heyrman amp
Swings (2001) isolated a strain originally classified as Paenibacillus sp LMG 19508
from biodeteriorated mural paintings in the Servilia tomb at the Roman necropolis of
Carmona in Seville Spain (Smerda et al 2006) Building stone and wall paintings contain
a variety of hydroscopic salts including carbonates chlorides nitrates sulfates etc
dispersed within the porous material or locally concentrated These salts are solubilised
and migrate with the water in and out of the stone Due to changes in physical parameters
the so called salt efflorescences appear on the surfaces providing extremely saline
environments and building niches for settlement of halophilic microorganisms Halite and
other hygroscopic salts can retain considerable quantities of moisture when entrapped in
the building materials and thus favouring the bacterial growth (Ripka 2005)
It is demonstrated that water-damaged indoor building materials contained
substances of microbial origin extremely toxic to eukaryotic cells and large quantities of
several microbial species known to be potentially toxic or immunopotentiating These
include peptidoglycans Gram-negative endotoxin β-13-D glucans lipoglycans and
teichoic acids and mycotoxins (Jimenez 2000) In turn these microorganisms can mediate
the crystallization process These crystallizations can produce destructive effects Some
salts may crystallize or recrystallize to different hydrates which occupy a larger space and
exert additional pressure producing cracking powdering and flaking
(Jimenez and Laiz 2000)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
26 Review of Literature
211 Types of deterioration on mural paintings
The frescos represent a variety of ecological niches where primary colonization is
due to photoautotrophic and chemolithoautotrophic microorganisms followed by
secondary colonization due to heterotrophic bacteria that obtain nutrients from various
sources (metabolites of autotrophic bacteria airborne organic contamination animal faeces
and organic compounds in the paint layers themselves) Microbial-induced deterioration
processes cause structural as well as aesthetic damage to wall paintings such as the
discoloration of materials the formation of crusts on surfaces and the loss of material
(Sarro et al 2006 Osburn et al 2011) Halophilic bacteria and archaea were thought to
be found only in extreme environments like salt lakes or black smokers However it has
been shown that mural paintings and stones are a common habitat for extremely salt
tolerant and moderate halophilic (Ripka 2005) Microbial induced deterioration processes
can cause different kinds of alterations such as discolouration of materials the formation of
crusts on surfaces and the loss of material which leads to structural damage (Ripka 2005)
First of all microorganisms can cause severe problems due to the excretion of aggressive
metabolic products such as organic or inorganic acids Secondly material components can
be used as substrates for microbial metabolism Exoenzymes such as cellulases proteases
tannases beta-glucosidase produced by fungi and bacteria are responsible for hydrolysis of
cellulose and proteins Further examples are mechanical processes caused by swelling and
shrinking of slime or mycelia penetrating inside plaster of the painting resulting in loss of
cohesion and detachment of the paint layer (Rolleke 1996 Gurtner et al 2000)
Table-21 Microbial damage on mural paintings (Rolleke 1996)
S No Damage Microbial activity
1 Green brown red grey
surface layers (patinas)
Pigments produced by microorganisms (intra-or
extracellular) as chlorophyll and carotinoids
2 Dislodging of painting layers Use of organic binders as nutrient and energy
source
3 Acid attack of carbonates Acid produced by fungi or bacteria
4 Discolouration of pigments Redox-reactions induced by fungi and
bacteria
5 Loss of paint layer Growth of microorganisms deep into the plaster
6 Hydrolysis of synthetic
polymers Chemoorganotrophic activity of bacteria and fungi
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
27 Review of Literature
Discolorations are caused by excretion of pigments and microbiologically induced
reductionoxidation-processes (Krumbein et al 1990) Degradation of the bindings is
followed by reduction of stability Oxidation of ammonium and reduced sulphur
compounds results in acidification of the environment such as Sulphuric acid and the
variety of organic acids produced by the heterotrophs cause solubilization of calcareous
binding material and chelation of metal ions (Bock et al 1993) It is now well recognised
that wall paintings can be deteriorated by microorganisms (Ciferri 1999)The growth of
microorganisms essentially results in two types of damage aesthetic and structural
Aesthetic damage implies pigment discoloration stains and formation of a biofilm on the
painted surface Structural damage is observed as cracking and disintegration of the paint
layer formation of paint blisters and degradation of support polymers or of glues and
binders resulting in detachment of paint layer from the support The colonization of mural
paintings by bacteria and other microorganisms can have different causes Provided that
favorable environmental conditions occur nutrients for heterotrophic bacteria and fungi
can be available from metabolites of autotrophic bacteria from airborne contamination and
dripping water from animal faeces but also from organic compounds in the paint layer
itself
212 Methods of studying biodeterioration
It is now well recognized that wall paintings may be deteriorated by
microorganisms as established by several studies that linked the observed damage with the
microbial community present as reviewed by Ciferri (1999) Despite this knowledge a
reliable characterization of bacteria associated with such damage is often lacking To
obtain greater insight into the bacterial community involved in biodeterioration of mural
paintings three sites (from the necropolis at Carmona Spain and the Saint-Catherine
chapel of the castle at Herberstein Austria) were sampled In previous studies from these
sites 385 isolates were analysed by fatty acid methyl ester GC and representatives of
different fatty acid clusters were further studied by 16S rRNA gene sequencing
(Heyrman and Swings 2001) Several of these representative strains showed the highest
sequence similarity with members of the genus Arthrobacter (Heyrman et al 2005)
Jimenez and Samson (1981) analysed the microbial flora of a large fresco painted
in the late 1920s in the monastery ldquoSanta Maria de la Rabidardquo (Huelva Spain) exhibiting
two types of deterioration white efflorescence and green-to-black stains
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
28 Review of Literature
Tate and Rebrikova (1990) thought autotrophic nitrifying bacteria to be the first colonisers
of damaged frescoes and building materials in the cathedral of the nativity of the Virgin in
the Pafnutii-Borovskii monastery (Russia) The bulk of research on biodeterioration of
mural paintings has focused on explaining the observed phenomena by analysing the
microflora present Following this approach a precise characterisation of the
microorganisms using a polyphasic approach was never the first goal
Only a few studies included genomic fingerprinting (16S rDNA sequence analysis)
for the characterisation of bacteria associated with damage on mural paintings
[Rolleke (1996) Pinar et al (2001)] Previous studies based on culture-dependent
techniques showed that the flora present on frescos are fungi (predominant species of
Penicillium Aspergillus Cladosporium and Engyodontium) (Guglielminetti et al 1994)
bacteria (predominant species of Bacillus Arthrobacter Micrococcus Streptomyces and
Pseudomonas) (Heyrman et al 1999) cyanobacteria and eukaryotic algae (species of
Nostoc Lyngbya and Chlorophyceae) (Arino et al 1996 Calvo et al 1993) The killing
effect of an antimicrobial agent on a microorganism can be assessed in several ways
(1) Lethal activity may be expressed as the rate of killing by a fixed concentration
of drug under controlled conditions This rate is determined by measuring the number of
viable bacteria at various time intervals The resulting graphic depiction is known as the
time-kill curve Bacterial killing rates are in part dependent on the class of antibiotic and
the concentration of this agent With certain classes of antibiotics (eg aminoglycosides
and fluoroquino-lones) the rate of killing increases with increased drug concentrations up
to a point of maximum effect This is termed concentration-dependent bactericidal activity
In contrast the killing rates of szlig-lactam agents and vancomycin are relatively slow and
continue only as long as the concentrations are in excess of the MIC This rate of killing is
termed time-dependent bactericidal activity
(2) The minimal concentration of drug needed to kill most of the viable organisms
after incubation for a fixed length of time (generally 24 hours) under a given set of
conditions is the most common estimation of bactericidal activity and is known as either
the minimal bactericidal concentration (MBC) or the minimal lethal concentration (MLC)
It will be referred to in this document as the MBC Unfortunately the definition of the
MBC (999 killing of the final inoculum) is somewhat arbitrary and separates the
bacteria into two populations ndash a segrega-tion which might not have biological relevance
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
29 Review of Literature
The determination of the MBC moreover is so subject to methodologic variables that the
clinical relevance of MBCs is nearly impossible to assess particularly for certain pathogen
and drug combinations (eg Staphylococci and beta-lactam agents)
(3) The serum of a patient receiving an antibiotic may be tested against the
infecting microorganism This can be done using time-kill curve methodology (ie serum
bactericidal rate) or using dilution methodology (ie serum bactericidal titer) The
principles of these methods as well as the influence of biological and technical factors are
similar (Barry et al 1999)
213 Microbial flora associated with deteriorated mural paintings
A great deal of research has been done in this field mainly by using cultivation dependent
methods However by using culture-dependent methods only a very small proportion of
microorganisms can be obtained Far less than 1 of organisms in the environment can be
cultivated by standard cultivation techniques (Pace 1996) Recent studies have shown that
culture-dependent techniques yielded mainly sporeforming bacteria suggesting that plating
leads to an over estimation of the number of spore-forming bacteria A wide number of
investigations have shown that in addition to chemical and physical processes
microorganisms play a major role in degradation of objects of art such as paintings stone-
works wood paper masonry leather parchment glass and metal (Ripka 2005)
A) Bacteria
In general growth of diverse organisms on mural paintings is supported by
humidity slight alkaline pH values and the presence of organic and inorganic nutrient
sources (Weirich 1989) In mural paintings pigments are suspended in water or oil often
binders such as casein and milk are used and they are supplied on the damp lime plaster
(Ciferri 1999) The calcium carbonate formed on contact with air consolidates the
pigments Thus frescos contain mainly inorganic components While chemoautotrophic
nitrifiers and thiobacilli obtain their energy for growth by oxidizing ammonium and
reducing sulphur-compounds respectively heterotrophic bacteria and fungi depend on
organically bound carbon [Tate et al (1991) Lazar (1971) Petushkova et al (1986)
Jimenez et al (1981)] Thus primary colonization of photoautotrophic Cyanobacteria
chemolithoautotrophic nitrifying bacteria and sulphuric acid producing thiobacilli represent
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
30 Review of Literature
the first supply of organic matter The death and lysis of such bacteria promotes the
secondary settlement of heterotrophic bacteria and fungal populations (Calvo et al 1991)
Bacteria may derive from plants or pollen as many sequences obtained in this study
gave high score similarities with bacteria isolated from plants like Moraxella osloensis
Enterobacter cloace Enterobacter agglomerans and Pantoea endophytica Bacteria may
also derive from animal faeces like flies Bacillus Pseudomonas Aeromonas and Panteoa
(Ripka 2005) As Lazar and Dumitru (1973) reported studying mural paintings in a
Romanian monastery the genera Bacillus Arthrobacter and Pseudomonas have been
proved to produce salt efflorescences and were even considered to cause the blanching
phenomenon of frescoes (Jimenez et al 2000) Predominant bacterial genera are Bacillus
Streptomyces Arthrobacter Micrococcus and Pseudomonas [Weirich (1989)
Tate et al (1990) Arroyo et al (1997) Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
B) Fungi
It may be concluded that there is wide variety of fungal forms present on mural
paintings but Aspergillus and Alternaria were found dominating from all the experimental
sites next to them were Cladosporium Drechestera Fusarium Curvularia Chaetomium
Memnoniella Mycelia sterelai Pencillium Emericella Stachybotrytis Trichoderma
Phoma Monodictys Humicola and Epicoccum (Garg et al 1995)
The fungal genera most commonly found in lists of isolated taxa given in literature
are Alternaria Aspergillus Chaetomium Cladosporium Fusarium Penicillium and
Verticullum [Weirich (1989) Tate et al (1990) Guglielminetti et al (1994)
Garg et al (1995) Berner et al (1997) Ciferri (1999)] Some fungi having hard fruiting
bodies represented by sclerotia pycnidia perithecia cleistothecia and stroma could
organize themselves inside the painted layer Many fungal forms having such structures
were identified from our experimental sites viz Emericella nidulans A flavus
Chaetomium sp and Phoma sp etc These structures with little increase in humidity may
cause swelling in the paint film (Garg 1995)
Strains of species of Alternaria and Cladosporium both of them identified on the
mural paintings of the Palace of Schoumlnbrunn are the most common genera isolated from
stone and mural paintings in indoor environments with standard cultivation methods
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
31 Review of Literature
(Ventosa 2004) Saprophytic species of the genus Cladosporium are among the most
abundant fungi isolated in saltern samples Commonly isolated Cyanobacteria belong to
Nostoc and eukaryotic algae to Lyngbya and members of the Chlorophyceae such as
Chlorella Pseudococcomyxa and Pseudopleurococcus [Gorbushina et al (1987)
Calvo et al (1993) Arino et al (1996)]
They grow optimally on media with low water activity due to high salt or sugar
concentrations seem to propagate 70 vegetatively in the salterns and are thus
halotolerantosmotolerant species rather than simple flush-through occurrences
Cladiosporum herbarum was frequently isolated from hypersaline waters dead and dying
plant material air soil food fruit cereals paint and textiles (Ventosa 2004)
C) Algae
Most of the painted areas in temperature climate became covered with green algae
(Pleurococcus Protococcus and Trentopholia) while under tropical conditions blue green
algae of the genera Oscillatoria and Sytonema predominated (Garg 1995) The main
factors which contribute to the growth of algae on wall paintings are the presence of
moisture in the plaster as well as availability of visible light These conditions are quite
prevalent in the tropical climate but in temperature regions also algal growth on wall
paintings have been reported [Tonolo et al (1961) Pietrini et al (1991)]
D) Actinomycetes
Usually literature refers to specific aspects eg the occurrence of cyanobacteria
and algae in caves with natural openings to sunlight or those with artificial lighting fungi
and so forth Actinomycetes have been considered to be mainly confined to soils where
they find their natural habitat but despite intensive studies there are still many gaps in our
knowledge of the role played by actinomycetes in soil processes and biodegrations of
murals cave paintings (Groth et al 1999) In addition halophilic bacteria actinomycetes
and cyanobacteria are also capable of growing on salt-affected mural paintings
(Karbowska 2003)
Monte and Ferrari (1993) reviewed the mechanisms of biodeterioration in tombs
and underground churches The role of actinomycetes in the deterioration of frescoes in
hypogean environments was stressed by Agarossi et al (1985) Monte and Ferrari (1993)
Giacobini et al (1987) described the serious damage suffered by a whole series of famous
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
32 Review of Literature
frescoes in underground environments Actinomycetes were isolated from these mural
paintings located in crypts caves and tombs About 200 strains of actinomycetes were
isolated 60 of which were identified The most frequent species were Streptomyces albus
S cinereoruber S griseolus S vinaceus and some members of the Nocardia genus
Heterotrophic bacteria and actinomycetes were the most abundant microorganisms
on the frescoes of Etruscan tombs (Agarossi et al 1985) Bettini et al (1977) studied
some of the oldest Etruscan tombs (7th to 4th century BC) and found white-grey patinas
and spots from streptomycetes in the mural paintings They related the biodeterioration to
the microclimatic conditions (eg lower temperatures high RH) Monte and Ferrari (1993)
considered that colonization of the mural paintings was the result of selective competitive
and inhibitory dynamics among different microorganisms under different and changing
environmental conditions The pigments excreted by some actinomycetes were responsible
for the violet stains found on the walls of tombs in Tarquinia Similar stains were observed
in one of the Roman tombs the Circular Mausoleum the Necropolis of Carmona Spain
from which a Streptomyces sp producing violet pigments in culture media was isolated
214 Identification of biodeteriogens
The possibility of pigments and biodeteriogens identification in frescos and stone
monitoring is offered mostly by vibrational spectroscopy infrared thermography laser
induced fluorescence (LIF) laser induced breakdown spectroscopy (LIBS) XRF (X-Ray
Fluorescence) IR and UV emission Among them laser based methods allowing for in
situ or remote characterization of artwork surface were applied successfully for
prospecting diagnosis and maintenance (Colao et al 2005) The rep-PCR fingerprinting
of the isolates allowed determination of their genotypic diversity Studies that have
compared rep-PCR genomic fingerprint analysis with DNAndashDNA relatedness studies have
shown that the two techniques yield results that are in close agreement [Nick et al (1999)
Rademaker et al (2000)] These studies therefore suggest that rep-PCR fingerprinting can
be used as a genomic screening method to differentiate at the species level and to select
representatives for DNAndashDNA reassociation experiments (Heymann et al 2003)
The characterisation of bacteria was for example often limited to isolation from
group-specific media followed by microscopy [Sorlini et al (1987) Weirich (1989)
Tate et al (1990) and in more recent studies to morphological and physiological
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
33 Review of Literature
characteristics including miniaturised and automated systems such as API and BIOLOG
[Arroyo et al (1997) Jimmenez et al (2000) and Laiz et al (2000)] or to
chemotaxonomic characteristics [Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
Wagner et al (1994) demonstrated that conventional microbiological efforts can
fail to isolate all microorganisms present in natural samples DNA-based techniques used
to identify microorganisms have revealed only a smaller fraction of bacteria isolated from
artworks (Ward et al 1990 Rolleke et al 1996) Bacterial identification using molecular
techniques especially those including the sequencing of genes coding for ribosomal
16S rRNA is very important to study bacterial communities found on artefacts One such
method is Denaturing Gradient Gel Electrophoresis (DGGE) of PCR-amplified gene
fragments coding for rRNA (Muyzer et al 1993) that allows the separation of partial
16S rDNA amplified fragments of identical length but different sequence due to their
different melting behaviour in a gel system containing a gradient of denaturants
(Jimenez 2003)
Total genomic DNA was purified for 16S rRNA gene sequencing and rep-PCR
using a slight modification of the method of Pitcher et al (1989) as described by
Heyndrickx et al (1996) rep-PCR genomic fingerprinting was performed with the REP-
and (GTG)5 primers (Versalovic et al 1994) using the PCR conditions described
previously by Rademaker et al (1997) Electrophoresis and pattern analysis were further
performed as described by Heyrman et al (2003) 16S rRNA gene sequencing and
phylogenetic analysis were performed as described by Heyrman and Swings (2001)
Phylogenetic trees were constructed using the BioNumerics software (Applied Maths) by
applying the neighbour-joining and maximum-parsimony methods on a multiple alignment
similarity matrix The stability of relationships was assessed by a bootstrap analysis of
1000 datasets For determination of the G+C content and levels of DNAndashDNA
hybridization approximately 1 g biomass was harvested from agar plates DNA was
purified by using a combination of the protocols of Marmur (1961) and
Pitcher et al (1989) as described by Logan et al (2000) The G+C content of the DNA
was determined by HPLC (Mesbah et al 1989) using the further specifications given by
Logan et al (2000) DNAndashDNA hybridization experiments were performed using a
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
34 Review of Literature
modification of the microplate method of Ezaki et al (1989) as described by
Willems et al (2001)
215 Preservation and conservation
Nowadays the conservation and preservation of our cultural heritage is one of the
world main concerns particularly in Europe The increasing need for non-destructive
investigation tools has become a major issue as sampling is in most cases restricted in
view of the value or the uniqueness of the object Artworks as wall paintings in buildings
and monuments of historical interest are affected by environment physical (temperature
and humidity) and biological factors (biodeteriogens) and by human (pollutant releases)
impact and therefore modified over the time The term ldquoconservationrdquo may have many
different meanings in different fields Every intervention directed to the restoration and
safeguard of works of art is commonly considered as a conservation treatment For
example conservation can involve the cleaning procedures set up by chemists or the photo
documentation of the preservation of historical memory For the appropriate conservation
of works of art even the lighting systems in a museum or the control of the visitorrsquos
movements in a site should be monitored Chemical degradation which induces the flaking
of paintings and deterioration from rain wind dust and other environmental causes is
mainly responsible for the weakening of the porous structure and the surface layers of the
materials used in works of cultural heritage (Colao et al 2005)
216 Conservation history
Wall paintings are an integral part of monuments and sites and should be preserved
in situ Many of the problems affecting wall paintings are linked to the poor condition of
the building or structure its improper use lack of maintenance frequent repairs and
alterations Also frequent restorations unnecessary uncovering and use of inappropriate
methods and materials can result in irreparable damage Substandard and inadequate
practices and professional qualifications have led to unfortunate results It is for this reason
that an appropriate document covering the principles of proper conservation-restoration of
wall paintings is necessary
The Venice Charter (1964) has provided general principles for the conservation-
restoration of cultural heritage The Amsterdam Declaration (1975) introducing the
concept of integrated conservation and the Nara Document on Authenticity (1994) dealing
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
35 Review of Literature
with cultural diversity have expanded these principles Taking into account these and
additional relevant contributions such as the ICOM-CC Code of Ethics (1984) Document
of Pavia (1997) and ECCO Professional Guidelines (1997) the aim of this document is
to provide more specific principles for the protection preservation and the conservation
restoration of wall paintings This document therefore reflects basic and universally
applicable principles and practices and does not take into account particular problems of
regions or countries which can be supplemented at regional and national level by
providing further recommendations where necessary
217 Preservation techniques of the mural paintings
The removal of fat salts varnishes and pollutants from the surfaces of the works
of art are mostly done by chemical and mechanical methods At the end of the 19th
century the practices of restoration methods that do not inhibit further future interventions
was considered acceptable During the 1960s several chemicals such as polymeric resins
were synthesized and applied as a consolidation or protection agents The accepted idea
was that these substances could be removed at any time leaving a completely unaltered
substrate On the basis of origin archaeological objects can be classified as follows
(Carretti 2005)
1 Inorganic It includes siliceous and nonsiliceous materials Archaeological materials
produced from stones terracotta ceramics and glass can be included under siliceous
materials whereas objects made of metals can be included under nonsiliceous inorganic
materials Again metal objects can be classified as ferrous metals and non-ferrous metals
Objects made of iron are termed as ferrous metal objects whereas metal objects made from
other than iron is termed as non-ferrous metal objects
2 Organic It includes archival and anthropological materials Again archival materials
include paper bhojapatra tadapatra textiles wooden objects miniature paintings whereas
anthropological objects include bone and ivory leather feather and fur etc
In the past restoration of paintings and other old artwork often involved application
of acrylic resins to consolidate and protect them One of the most important tasks for
modern restorers is thus to remove these layers because it turns out that acrylic resins not
only by drastically changing the optics of the treated artwork but in many cases they
accelerate their degradation The scientists use an oil-in-water microemulsion with the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
36 Review of Literature
organic solvent para-xylene as the oil component The matrix makes the cleaning agent
viscous so that it cannot enter very far into the pores of a painting (Carretti 2005)
Nanoparticle treatment is the logical evolution of the Ferroni-Dini method
Dispersions of kinetically stable Ca (OH)2 nanoparticles in non-aqueous solvents solved
most of the drawbacks of the microsized powders Stable dispersions of calcium hydroxide
have been successfully applied (replacing polymers) as fixatives to re-adhere lifted paint
layers during many restoration workshops in Italy and in Europe as a consolidant The
FerronindashDini method (two steps the application of a saturated solution of ammonium
carbonate (NH4)2CO3 and the treatment with a barium hydroxide solution Ba(OH)2 also
called the barium method has long been the acknowledged method for the removal of
salts that threaten paintings reinforcing at the same time the porous structure However
commercially available carbonates and hydroxide powders have dimensions of several
micrometres much larger than the pores on the paint surface This means they donrsquot
penetrate the painting well and there is also a risk of damaging the artwork by a white
glaze forming on the surface (Berger 2006) Restoration should provide the reinforcement
of the porous structure and the consolidation of the surface layer of arte facts A few
simple principles can be considered to define the most appropriate restoration method
1) The treatment should be reversible so that one can revert to the original status of the
work of art at any desired time
2) All the applied chemicals must ensure the maximum durability and the chemical
inertness
3) The applied chemicals must invert the degradation processes without altering the
chemical composition of the artefacts and their physico-chemical and mechanical
properties (Baglioni 2006)
218 Commercial preservative used for preservation of mural paintings
Cleaning was done using soft brushes vacuum cleaner and Gumma paine (dough)
a natural latex sponge Areas near the window were very dirty with black soot and were
cleaned with micro fibrous cloths moistened with synperonic N (surfactant alkyl phenol
ethoxylate based on nonyl phenol) and neutralized with clean water In several places the
paint layers had separated from the substrate (exfoli-ation) In that cases loose paint flakes
were stuck back using Paraloid B72 (10 solution in ethanol) as sparingly as possible
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
37 Review of Literature
Paraloid was injected with syringe behind the exfoliated area twice pushed and held back
with Melinex (polyester film) until fixed on the third application (Bionda et al 2002)
In a period of significant growth of molds and intensive efforts to stop the mold
contamination some of the lines of certain paintings were obscured or faded Solutions of
ethanol formalin 91 and Thiabendazole (TBZ) were used but they were not very
effective Para-formaldehyde fumigation was adopted beginning in 1981 to establish an
emergency treatment sensitivity of microorganisms from studied samples was tested
against Desogen by adding 1-3 (v v) in serial dilutions The best concentration
3 (vv) was applied with a brush to prevent spreading of the spores In order to overcome
the problem of fungal attack suitable fungicides carbendizeme or kiroxy-I or 5 solute of
N formaldehyde can be used Shellac solution in spirit or 2 solution of polyvinaycletate
in toluene can be used as preservative and consolidantsTo control insect and fungal attack
fumigants like pyrethrum DDT or 5 solution of sodium penta chlorophenate in kerosene
oil 2 to 5 solution of PVA in toluene or 2 to 5 solution of paraloid B-72 in toluene or
acetone be used (Miura 2009) Microclimatic conditions constitute a critical factor in the
conservation of cave paintings The unstable microclimatic condition is one of the factors
that always affect the state of conservation of mural paintings In the environmental-
monument system knowledge of the functional environment and climatic conditions of the
surroundings are necessary for the identification of causes of decay (Singh 2011)
Furthermore the risk of formation of indoor bioaerosols in residential and public
buildings (offices schools museums etc) has attracted interest in the last years due to
socio-economic as well as sanitary reasons (Ripka 2005) Thus it is important in aspects of
health and maintenance of Cultural Heritage to analyse the complete microflora to further
develop biocides for harmful microorganisms and methods for restoration of damaged
objects of art The biocidal testing was carried out on one representative algal species of
the two classes of algae viz Chlorococcum sp (green) and Chroococcus sp (blue-green)
found to be common in all the samples Efficiency tests were carried out both in liquid as
well as solid media containing algal suspensions by adding a biocide solution of known
concentration and determining the growth of the microorganism after the incubation
period The biocides used for the past studies were
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
17 Review of Literature
Figure-214 Sculpture of Mahabalipuram
26 Methods of mural painting
In the history of mural several methods have been used The Buon fresco technique
consists of painting in pigment mixed with water on a thin layer of wet fresh lime mortar
or plaster The pigment is then absorbed by the wet plaster after a number of hours the
plaster dries and reacts with the air it is this chemical reaction which fixes the pigment
particles in the plaster After this the painting stays for a long time up to centuries in fresh
and brilliant colors A Secco painting is done on dry plaster The pigments thus require a
binding medium such as egg (tempera) glue or oil to attach the pigment to the wall
Mezzo-fresco is painted on nearly-dry plaster which is defined by the sixteenth-century
author Ignazio Pozzo as ldquofirm enough not to take a thumb-printrdquo so that the pigment only
penetrates slightly into the plaster Ancestral Hopi village archaeologists found that
fourteen kivas had painted murals and multiple layers of murals on the walls some with up
to twenty-seven layers of murals (Saturno 2006)
The colors used in painting are generally obtained from plants and minerals
Among them only such colors which are lime resistant are suitable for mural painting The
selection of proper colors for a mural painting is an important part of the work as the
longevity the painting depends on it Only mineral colors are preserved for a long time
which could be the reason for use of those colors in early days As per ldquoShilpa ratnardquo and
ldquoAgnipuranardquo the colors used in mural painting are white black red yellow blue and
green Yellow and red are from yellow ochre and red ochre Blue is generally indigo or
china blue White is the prepared wall and black is the carbon soot Mural paintings have
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
18 Review of Literature
survived centuries only on account of the identification and use of those colors which does
not have any reaction with lime (Miraseth 2006)
Originally three types of brushes were made and used flat medium and fine Flat
brushes were made from hairs behind calfrsquos ear the medium from the bottom of goats
belly and the fine brush from delicate blades of grass However in due course of time and
change use of easily available brushes from commercial market and shading of the
original colours can be distinctively noticed The use of blue colour is also noticed over the
passage of time The paintings have been brought down from the walls to plywood cloth
paper and other frames for easy to make and use purposes (Chakarabarti 1980)
27 Themes of mural painting
The subjects and themes in the murals are centered on the Hindu pantheon of Gods
and Goddesses drawn from description in the invocatory verses or Dhyana Slokas More
common representations are of Vishnu in different incarnations Ganesha and
manifestations of Siva We see murals in the Pallimanna Siva Temple devoted to Siva-
Parvatirsquos marriage the Ramayana Story being narrated on the walls of the Mattancheri
palace in the Sankara Narayana the Mahabharata is retold Murals are various scenes from
the Hindu epics and also the frolics of Lord Krishna
It would be interesting to bring into account the influence of the mural paintings on
Christianity On various churches like the St Georgersquos Orthodox Church has Christian
murals bringing out biblical characters and narrating stories from the scriptures Mar
Sabore and Afroth Church at Akapparambu in the outskirts of Ernakulam also have murals
of scenes from the bible Interestingly StMaryrsquos Church at Kanjoor has on both sides of its
entrance a battle scene between the armies of Tipu Sultan and of the English East India
Company It is also apparent that the history of Kerala Murals has its origin in the temple
walls and thus a study of Kerala Murals is not complete without pondering on the
architecture of Kerala its association with the murals (Warrier 2011)
28 Technique used in mural paintings
Indian murals executed on walls of caves structural temples walls of palaces were
based on highly developed techniques Mural painting is a composite structure of these
three basic layers the support the ground and the pigment layer In case of wall painting
the wall itself is the support This is followed by the layer or layers of plaster which
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
19 Review of Literature
constitute the ground The pigment layer is the one which contains the picture The support
is the wall which may be rock surface in a cave or a structural one These stone surfaces
which serve as carriers are rough or uneven This unevenness is itself an advantage as it
provides ldquotoothrdquo to hold the plaster on the surface The uneven surface of the wall has to be
made uniform with layers of plaster in successive gradation of fineness There is generally
one layer of rough plaster followed by one or more layers of fine plaster Ground or plaster
is a term used to mean the surface material of a wall or building which is applied as a
plastic mass made by mixing certain materials with water letting the mass set by drying
carbonation or hydration The active or setting components of plaster are commonly clay
which sets by drying lime which sets by carbonation gypsum and pozzolana which sets by
hydration (Mini 2010)
There are different mixtures for rough plaster In all the mixtures clay limestone
lime and shells in powdered form serve as the matrix The particles of which are held
together by the organic materials like gum glue extracts from barks etc are in fact
adhesives The fine plaster layer requires more careful preparation because it is the layer on
which the pigments are laid to make the picture ldquoShilparatnardquo suggest a mixture of conch
Oyster shells or white clay with gum of neem or slaked lime and coconut water Here the
consolidation is effected by the carbonation of slaked lime ie it absorbs carbon dioxide
from air and becomes carbonate Mural paintings were lime-washed from the 17th until the
beginning of 19th century A few paintings in vaults were never lime-washed for example
at Taby and Floda painted by the medieval painter Albertus Pictor (Mini 2010)
All the paintings have certain basic common characteristics There has to be a wall
or rock surface called support over which the artist goes to work A plaster base called
ground of varied thickness is laid on the support The ground may consist of one or more
layers The strength and life of the whole mural depended up on this ground over which the
painting was done It is the process of applying the final painting on the ground determines
the character of the mural whether it is fresco or tempera The mural painting is done
usually by creating wall surface free of any previous oil or paint by using solvent or by
sand blasting The brick wall is first plastered with mixture of lime and sand in the ratio of
12 A mixture of egg yolk vinegar oil colour is used in dry plaster
There are at least six stages before a Kerala Mural Painting is complete Lekhya
Karma is the first stage where sketching by pencil or crayon is done The second stage is
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
20 Review of Literature
the Rekha Karma which enhances the outlines of the sketching done The third stage called
Varna Karma breathes life into the painting with its colours Here all colours are
appropriately filled in The colouring of the human figures is done according to the
characters and their common virtues The divine and noble characters (Saatvik) are painted
in green those inclined towards power and wealth (Raajasik) is painted in shades of red
lowly mean characters (Tamasik) in white and demons in black In the fourth stage or the
Vartana Karma shading is done Fifth stage called the Lekha Karma brings us to the final
outline of the painting which is usually in black The final and the finishing touches stage
are called Devika Karma (Warrier 2011)
29 Dyes used in mural painting
Indians have been considered as fore runners in the art of natural dyeing Natural
dyes find use in the colouring of textiles drugs cosmetics etc Owing to their non-toxic
effects they are also used for colouring various food products In India there are more
than 450 plants that can yield dyes In addition to their dye-yielding characteristics some
of these plants also possess medicinal value Though there is a large plant resource base
little has been exploited so far Due to lack of availability of precise technical knowledge
on the extracting and dyeing technique it has not commercially succeeded like the
synthetic dyes (Siva 2007)
The color materials on the mural paintings in ancient India were derived from the
natural materials like terracotta chalk red ochre and yellow ochre mixed with animal fat
The dyes for painting is prepared such as white from lime Black from carbon soot of
lamps Red and yellow from minerals Blue from indigo ferra Deep red from lac A fine
coating of resin is done after the painting in order to make a shining appearance Egg yolk
and vinegar was mixed with oil colors and painted on dry plaster (Krishnakumar 1999)
Although plants exhibit a wide range of colours not all of these pigments can be
used as dyes Some do not dissolve in water some cannot be adsorbed onto fibres whereas
others fade when washed or exposed to air or sunlight It remains a mystery why plants
reward us with vibrant dyes India has a rich biodiversity and it is not only one of the
worldrsquos twelve mega diversity countries but also one of the eight major centres of origin
and diversification of domesticated taxa It has approximately 490000 plant species of
which about 17500 are angiosperms more than 400 are domesticated crop species and
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
21 Review of Literature
almost an equal number their wild relatives Thus India harbours a wealth of useful
germplasm resources and there is no doubt that the plant kingdom is a treasure-house of
diverse natural products One such product from nature is the dye (Siva 2007)
Many natural dyestuff and stains were obtained mainly from plants and dominated
as sources of natural dyes producing different colours like red yellow blue black brown
and a combination of these Almost all parts of the plants like root bark leaf fruit wood
seed flower etc produce dyes It is interesting to note that over 2000 pigments are
synthesized by various parts of plants of which only about 150 have been commercially
exploited Nearly 450 taxa are known to yield dyes in India alone of which 50 are
considered to be the most important ten of these are from roots four from barks five from
leaves seven from flowers seven from fruits three from seeds eight from wood and three
from gums and resins Some important dye-yielding plant habitats their distribution and
colouring pigment (Siva 2007)
The dye is generally prepared by boiling the crushed powder with water but
sometimes it is left to steep in cold water The solution then obtained is used generally to
dye coarse cotton fabrics Alum is generally used as a mordant Flowers of Butea
monosperma (Lam) Taubert yield an orange-coloured dye which is not fast and is easily
washed away For the purpose of colouring the material is steeped in a hot or cold
decoction of the flowers A more permanent colour is produced either by first preparing the
cloth with alum and wood ash or by adding these substances to the dye-bath The dye
indigo is produced by steeping the plant in water and allowing it to ferment This is
followed by oxidation of the solution with air in a separate vessel Mallotus philippinensis
muell yields an orange colour used for dyeing silk and wool To prepare the annatto dye
from B orellena the fruits are collected when nearly ripe The seeds and pulp are removed
from the mature fruit and macerated with water Thereafter they are either ground up into
an lsquoannatto pastersquo or dried and marketed as annatto seeds Sometimes when the seeds and
pulp are macerated with water the product is stained through a sieve and the colouring
matter which settles out is collected and partially evaporated by heat and finally dried in
the sun (Sowbhagya 2002)
The predominant colors used in rock art and cave art are black (from charcoal soot
or manganese oxide) yellow ochre (limonite) red ochre (hematite or baked limonite) and
white (kaolin clay burnt shells powdered gypsum or powdered calcium carbonate) All of
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
22 Review of Literature
theses pigments may be used on leather or raw hide as well Early cave art in Seminole
Canyon was monochromatic in red and as culture grew more sophisticated the color
palette expanded Blue Orange Brown Green and Purple are the most common colours
used in Ajantha murals White Pink Gold are occasionally represented mineral earths
containing ferric oxide and copper carbonates were used as source of red yellow and green
colours There is also evidence to establish that root of Rubia cardifolia and leaves of
Indigofera tinctoria were used as source for red and blue colours (Nayer et al 1999)
Many colors of pigments were obtained from both organic and inorganic sources in
ancient times and used to paint various surfaces such as braintan leather clothing and
accoutrements rawhide the human body etc Blue color was obtained from powdered
azurite and lapis duck manure and certain clays Fine Blue-green clay was obtained from
deposits near Mankato Michigan Organic sources of blue include Turkeys Tail a
greenish blue polypore that grows on dead decaying wood (not tannish ones) Native
Americans get Indigo from either Guatemala or Ecuador which was traded well up onto
Kansas long before the Spanish ever set foot here American Indigo has purple tones to it
but IndianJapanese indigo has green tones Berries and crushed flowers were also used to
obtain blue color by rubbing the plant material directly on the leather
An organic source of red was Cochineal It was native west of the Mississippi and
is produced from the bodies of small insects that grow on the prickly pear cactus Ladys
Bedstraw gives a good vermillion red color Harvest the roots dry them out clean the mud
etc off of them and then grind the roots really fine then soak them to extract the red
coloring The key here is drying the root first Blood was also used as red pigment Pucoon
roots also yield a red pigment (Smith 2002) Red ochre the reverse original red colours are
due to variations in iron oxide (or) calcite content and to redox conditions in the firing
produced Brown coloured ceramics owe their colour to maghemite and must be
considered as a fabrication defect due to the position of the ceramic piece in a zone where a
reducing atmosphere prevailed in the course of firingRed pigments were produced from
iron oxides like hematite or limonite and from ochre Hematite was the most frequently
used mineral It occurs in the form of aggregates of small red crystals or in the form of
bigger black crystals which are difficult to crush white was obtained mostly from
kaolinite or illite (Clottes et al 1990)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
23 Review of Literature
210 Biodetoriation of mural paintings
Historic items often contain natural biodegradable materials and have histories of
exposure to moist conditions These two conditions make them amenable to microbial
attack Microbial colonization may damage the building or the cultural asset
(Salonen 2001) Biodeteriogens are organisms involved in deterioration of artifacts They
are very specific for each type of artifact in accordance with its chemical structure and
environment They also have different nutritional requirements and act directly or
indirectly on the substrate The adhesion of microorganisms to a substrate is the result of
cell hydrophobicity and of excreted polymeric substances contained by sheaths capsules
and slimes (Colao 2005)
The surviving wall paintings and decorations in subterranean environments around
Malta are rather scarce (Buhagiar 1986 1993 1998) These include those at St Paulrsquos
Catacombs (Zammit 2008) St Agatharsquos Crypt and Catacombs (Camilleri 2001)
San Catald Catacombs Tac-Cghaqi Abbatija tad-Dejr (Buhagiar 1993) all in Rabat the
cave-sanctuary in Mellieħa (Buhagiar 1987) and the Ħal Saflieni Hypogeum in Paola
(Pace 2000) Previous studies conducted on wall paintings and decorations in Maltese
Palaeo-Christian Catacombs have involved their manufacturing techniques (Muscat 2005)
However to date limited systematic studies have been conducted into the biodeterioration
in Maltese Palaeo- Christian Catacombs The only such studies ever conducted in Malta
concerned the biodeterioration of works of art in catacombs have been carried out at St
Agatharsquos Crypt and Catacombs in Rabat (Zammit et al 2008 Psaila 2006)
Microorganisms can be responsible for the destruction of monuments buildings
and cultural heritage assets including the decay of concrete cement stones mural
paintings etc These microorganisms are not only related with biodeterioration but water-
damaged indoor building materials are frequently colonized by complex bacterial
communities and may emit mixed bioaerosols into the indoor air (Jimenez 2000) It is
well known that mural paintings are colonized by micro-organisms and can be severely
damaged by such growths (Ciferri 1999) A large number of fungal (gt50) and bacterial
taxa (70) have been detected in indoor environments Over 50 bacterial species and 14
genera novel to science were reported in the past 10 years from indoor air and historic
items indicating bacterigravea in these enviroments are as yet only fragmentarily known
(Salonen 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
24 Review of Literature
Traditionally the study of microflora which causes this biodeterioration was based
on classical cultivation methods that were mainly useful to study the physiological
potential of microorganisms but do not provide information on all microbial communities
to be found in excavated artifacts Indeed many studies using culture-independent
techniques which cultivate microorganisms from different environments may often
represent only minor components of the microbial community as a whole It is generally
accepted that cultivation methods recover less than 1 of the total microorganisms present
in environmental samples (Ward et al 1990 Amann et al 1995) Hence microbial
investigations based only on cultivation strategies cannot be regarded as reliable in terms
of reflecting the microbial diversity present in objects of art (Osburn et al 2011)
Early workers suggested that the presence of living microorganisms on stone
increased its susceptibility to damage through their water-binding capacity It has recently
been reported that the mineralogy porosity surface roughness and capacity to collect
water and organic materials control its bioreceptivity and tendency to biodeterioration
(Diakumaku 1995) In addition environmental factors as temperature light pH and
relative humidity affect the number and type of colonising species (Tiano et al 1995) and
hence the progress of colonisation Biofilms on decayed stones consist on mixed microbial
populations embedded in a polymeric matrix Fungi algae filamentous and unicellular
bacteria are found in these complex communities A variety of bacteria have been isolated
from different stone samples confirming the dominance of Gram-positive organisms
especially spore-forming bacteria such as Bacillus and filamentous actinomycetes
(Ripka 2005)
In cultivation studies of deteriorated mural and rock paintings bacterial isolates
have frequently been attributed to the genus Bacillus (Weirich 1989 Tate and Rebrikova
1991 Gonzalez et al 1999 Heyrman et al 1999 Jimenez et al 2000) Other studies that
have included DNA-based techniques to characterize the bacterial community involved in
biodeterioration have shown that a substantial part of the bacterial population is made up of
so far unknown species (Altenburger et al 1996 Rolleke et al 1996 Gurtner et al 2000
Heyrman and Swings 2001) (Heymann et al 2003)
Many potential mycotoxin producers have been detected in air and items from
indoor environments with histories of exposure to moisture for example species of
Acremonium Alternaria Aspergillus Chateomium Fusarium Eurotium Paecilomyces
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
25 Review of Literature
Penicillium Scopulariopsis Stachybotrys Trichoderma Verticillium and Wallemia
(Peltola et al 2001 Pieckova et al 2001) Not all strains of one species produce
mycotoxins and different strains may produce different toxins Whereas toxin producing
strains are frequent in crops and outdoor vegetation toxin producing isolates from indoor
environments and non living assets have only been reported of the species Aspergillus
versicolor (Nielsen et al 1998) Stachybotrys chartarum Nikulin (1997) and
Trichoderma harzianum (Peltola et al 2001) Streptomyces griseus strains producing
valinomycin occur in environments where humans can get exposed
(Andersson et al 2002) The biological properties and toxicity mechanisms of cereulide
were identical to those by valinomycin (Mikkola et al 1999 Salonen et al 2001)
The genus Paenibacillus was first proposed by Ash et al (1993) and its description
was emended by Shida et al (1997) The genus Paenibacillus is under intensive taxonomic
investigation with ten species having been formally described in the last year Heyrman amp
Swings (2001) isolated a strain originally classified as Paenibacillus sp LMG 19508
from biodeteriorated mural paintings in the Servilia tomb at the Roman necropolis of
Carmona in Seville Spain (Smerda et al 2006) Building stone and wall paintings contain
a variety of hydroscopic salts including carbonates chlorides nitrates sulfates etc
dispersed within the porous material or locally concentrated These salts are solubilised
and migrate with the water in and out of the stone Due to changes in physical parameters
the so called salt efflorescences appear on the surfaces providing extremely saline
environments and building niches for settlement of halophilic microorganisms Halite and
other hygroscopic salts can retain considerable quantities of moisture when entrapped in
the building materials and thus favouring the bacterial growth (Ripka 2005)
It is demonstrated that water-damaged indoor building materials contained
substances of microbial origin extremely toxic to eukaryotic cells and large quantities of
several microbial species known to be potentially toxic or immunopotentiating These
include peptidoglycans Gram-negative endotoxin β-13-D glucans lipoglycans and
teichoic acids and mycotoxins (Jimenez 2000) In turn these microorganisms can mediate
the crystallization process These crystallizations can produce destructive effects Some
salts may crystallize or recrystallize to different hydrates which occupy a larger space and
exert additional pressure producing cracking powdering and flaking
(Jimenez and Laiz 2000)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
26 Review of Literature
211 Types of deterioration on mural paintings
The frescos represent a variety of ecological niches where primary colonization is
due to photoautotrophic and chemolithoautotrophic microorganisms followed by
secondary colonization due to heterotrophic bacteria that obtain nutrients from various
sources (metabolites of autotrophic bacteria airborne organic contamination animal faeces
and organic compounds in the paint layers themselves) Microbial-induced deterioration
processes cause structural as well as aesthetic damage to wall paintings such as the
discoloration of materials the formation of crusts on surfaces and the loss of material
(Sarro et al 2006 Osburn et al 2011) Halophilic bacteria and archaea were thought to
be found only in extreme environments like salt lakes or black smokers However it has
been shown that mural paintings and stones are a common habitat for extremely salt
tolerant and moderate halophilic (Ripka 2005) Microbial induced deterioration processes
can cause different kinds of alterations such as discolouration of materials the formation of
crusts on surfaces and the loss of material which leads to structural damage (Ripka 2005)
First of all microorganisms can cause severe problems due to the excretion of aggressive
metabolic products such as organic or inorganic acids Secondly material components can
be used as substrates for microbial metabolism Exoenzymes such as cellulases proteases
tannases beta-glucosidase produced by fungi and bacteria are responsible for hydrolysis of
cellulose and proteins Further examples are mechanical processes caused by swelling and
shrinking of slime or mycelia penetrating inside plaster of the painting resulting in loss of
cohesion and detachment of the paint layer (Rolleke 1996 Gurtner et al 2000)
Table-21 Microbial damage on mural paintings (Rolleke 1996)
S No Damage Microbial activity
1 Green brown red grey
surface layers (patinas)
Pigments produced by microorganisms (intra-or
extracellular) as chlorophyll and carotinoids
2 Dislodging of painting layers Use of organic binders as nutrient and energy
source
3 Acid attack of carbonates Acid produced by fungi or bacteria
4 Discolouration of pigments Redox-reactions induced by fungi and
bacteria
5 Loss of paint layer Growth of microorganisms deep into the plaster
6 Hydrolysis of synthetic
polymers Chemoorganotrophic activity of bacteria and fungi
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
27 Review of Literature
Discolorations are caused by excretion of pigments and microbiologically induced
reductionoxidation-processes (Krumbein et al 1990) Degradation of the bindings is
followed by reduction of stability Oxidation of ammonium and reduced sulphur
compounds results in acidification of the environment such as Sulphuric acid and the
variety of organic acids produced by the heterotrophs cause solubilization of calcareous
binding material and chelation of metal ions (Bock et al 1993) It is now well recognised
that wall paintings can be deteriorated by microorganisms (Ciferri 1999)The growth of
microorganisms essentially results in two types of damage aesthetic and structural
Aesthetic damage implies pigment discoloration stains and formation of a biofilm on the
painted surface Structural damage is observed as cracking and disintegration of the paint
layer formation of paint blisters and degradation of support polymers or of glues and
binders resulting in detachment of paint layer from the support The colonization of mural
paintings by bacteria and other microorganisms can have different causes Provided that
favorable environmental conditions occur nutrients for heterotrophic bacteria and fungi
can be available from metabolites of autotrophic bacteria from airborne contamination and
dripping water from animal faeces but also from organic compounds in the paint layer
itself
212 Methods of studying biodeterioration
It is now well recognized that wall paintings may be deteriorated by
microorganisms as established by several studies that linked the observed damage with the
microbial community present as reviewed by Ciferri (1999) Despite this knowledge a
reliable characterization of bacteria associated with such damage is often lacking To
obtain greater insight into the bacterial community involved in biodeterioration of mural
paintings three sites (from the necropolis at Carmona Spain and the Saint-Catherine
chapel of the castle at Herberstein Austria) were sampled In previous studies from these
sites 385 isolates were analysed by fatty acid methyl ester GC and representatives of
different fatty acid clusters were further studied by 16S rRNA gene sequencing
(Heyrman and Swings 2001) Several of these representative strains showed the highest
sequence similarity with members of the genus Arthrobacter (Heyrman et al 2005)
Jimenez and Samson (1981) analysed the microbial flora of a large fresco painted
in the late 1920s in the monastery ldquoSanta Maria de la Rabidardquo (Huelva Spain) exhibiting
two types of deterioration white efflorescence and green-to-black stains
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
28 Review of Literature
Tate and Rebrikova (1990) thought autotrophic nitrifying bacteria to be the first colonisers
of damaged frescoes and building materials in the cathedral of the nativity of the Virgin in
the Pafnutii-Borovskii monastery (Russia) The bulk of research on biodeterioration of
mural paintings has focused on explaining the observed phenomena by analysing the
microflora present Following this approach a precise characterisation of the
microorganisms using a polyphasic approach was never the first goal
Only a few studies included genomic fingerprinting (16S rDNA sequence analysis)
for the characterisation of bacteria associated with damage on mural paintings
[Rolleke (1996) Pinar et al (2001)] Previous studies based on culture-dependent
techniques showed that the flora present on frescos are fungi (predominant species of
Penicillium Aspergillus Cladosporium and Engyodontium) (Guglielminetti et al 1994)
bacteria (predominant species of Bacillus Arthrobacter Micrococcus Streptomyces and
Pseudomonas) (Heyrman et al 1999) cyanobacteria and eukaryotic algae (species of
Nostoc Lyngbya and Chlorophyceae) (Arino et al 1996 Calvo et al 1993) The killing
effect of an antimicrobial agent on a microorganism can be assessed in several ways
(1) Lethal activity may be expressed as the rate of killing by a fixed concentration
of drug under controlled conditions This rate is determined by measuring the number of
viable bacteria at various time intervals The resulting graphic depiction is known as the
time-kill curve Bacterial killing rates are in part dependent on the class of antibiotic and
the concentration of this agent With certain classes of antibiotics (eg aminoglycosides
and fluoroquino-lones) the rate of killing increases with increased drug concentrations up
to a point of maximum effect This is termed concentration-dependent bactericidal activity
In contrast the killing rates of szlig-lactam agents and vancomycin are relatively slow and
continue only as long as the concentrations are in excess of the MIC This rate of killing is
termed time-dependent bactericidal activity
(2) The minimal concentration of drug needed to kill most of the viable organisms
after incubation for a fixed length of time (generally 24 hours) under a given set of
conditions is the most common estimation of bactericidal activity and is known as either
the minimal bactericidal concentration (MBC) or the minimal lethal concentration (MLC)
It will be referred to in this document as the MBC Unfortunately the definition of the
MBC (999 killing of the final inoculum) is somewhat arbitrary and separates the
bacteria into two populations ndash a segrega-tion which might not have biological relevance
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
29 Review of Literature
The determination of the MBC moreover is so subject to methodologic variables that the
clinical relevance of MBCs is nearly impossible to assess particularly for certain pathogen
and drug combinations (eg Staphylococci and beta-lactam agents)
(3) The serum of a patient receiving an antibiotic may be tested against the
infecting microorganism This can be done using time-kill curve methodology (ie serum
bactericidal rate) or using dilution methodology (ie serum bactericidal titer) The
principles of these methods as well as the influence of biological and technical factors are
similar (Barry et al 1999)
213 Microbial flora associated with deteriorated mural paintings
A great deal of research has been done in this field mainly by using cultivation dependent
methods However by using culture-dependent methods only a very small proportion of
microorganisms can be obtained Far less than 1 of organisms in the environment can be
cultivated by standard cultivation techniques (Pace 1996) Recent studies have shown that
culture-dependent techniques yielded mainly sporeforming bacteria suggesting that plating
leads to an over estimation of the number of spore-forming bacteria A wide number of
investigations have shown that in addition to chemical and physical processes
microorganisms play a major role in degradation of objects of art such as paintings stone-
works wood paper masonry leather parchment glass and metal (Ripka 2005)
A) Bacteria
In general growth of diverse organisms on mural paintings is supported by
humidity slight alkaline pH values and the presence of organic and inorganic nutrient
sources (Weirich 1989) In mural paintings pigments are suspended in water or oil often
binders such as casein and milk are used and they are supplied on the damp lime plaster
(Ciferri 1999) The calcium carbonate formed on contact with air consolidates the
pigments Thus frescos contain mainly inorganic components While chemoautotrophic
nitrifiers and thiobacilli obtain their energy for growth by oxidizing ammonium and
reducing sulphur-compounds respectively heterotrophic bacteria and fungi depend on
organically bound carbon [Tate et al (1991) Lazar (1971) Petushkova et al (1986)
Jimenez et al (1981)] Thus primary colonization of photoautotrophic Cyanobacteria
chemolithoautotrophic nitrifying bacteria and sulphuric acid producing thiobacilli represent
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
30 Review of Literature
the first supply of organic matter The death and lysis of such bacteria promotes the
secondary settlement of heterotrophic bacteria and fungal populations (Calvo et al 1991)
Bacteria may derive from plants or pollen as many sequences obtained in this study
gave high score similarities with bacteria isolated from plants like Moraxella osloensis
Enterobacter cloace Enterobacter agglomerans and Pantoea endophytica Bacteria may
also derive from animal faeces like flies Bacillus Pseudomonas Aeromonas and Panteoa
(Ripka 2005) As Lazar and Dumitru (1973) reported studying mural paintings in a
Romanian monastery the genera Bacillus Arthrobacter and Pseudomonas have been
proved to produce salt efflorescences and were even considered to cause the blanching
phenomenon of frescoes (Jimenez et al 2000) Predominant bacterial genera are Bacillus
Streptomyces Arthrobacter Micrococcus and Pseudomonas [Weirich (1989)
Tate et al (1990) Arroyo et al (1997) Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
B) Fungi
It may be concluded that there is wide variety of fungal forms present on mural
paintings but Aspergillus and Alternaria were found dominating from all the experimental
sites next to them were Cladosporium Drechestera Fusarium Curvularia Chaetomium
Memnoniella Mycelia sterelai Pencillium Emericella Stachybotrytis Trichoderma
Phoma Monodictys Humicola and Epicoccum (Garg et al 1995)
The fungal genera most commonly found in lists of isolated taxa given in literature
are Alternaria Aspergillus Chaetomium Cladosporium Fusarium Penicillium and
Verticullum [Weirich (1989) Tate et al (1990) Guglielminetti et al (1994)
Garg et al (1995) Berner et al (1997) Ciferri (1999)] Some fungi having hard fruiting
bodies represented by sclerotia pycnidia perithecia cleistothecia and stroma could
organize themselves inside the painted layer Many fungal forms having such structures
were identified from our experimental sites viz Emericella nidulans A flavus
Chaetomium sp and Phoma sp etc These structures with little increase in humidity may
cause swelling in the paint film (Garg 1995)
Strains of species of Alternaria and Cladosporium both of them identified on the
mural paintings of the Palace of Schoumlnbrunn are the most common genera isolated from
stone and mural paintings in indoor environments with standard cultivation methods
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
31 Review of Literature
(Ventosa 2004) Saprophytic species of the genus Cladosporium are among the most
abundant fungi isolated in saltern samples Commonly isolated Cyanobacteria belong to
Nostoc and eukaryotic algae to Lyngbya and members of the Chlorophyceae such as
Chlorella Pseudococcomyxa and Pseudopleurococcus [Gorbushina et al (1987)
Calvo et al (1993) Arino et al (1996)]
They grow optimally on media with low water activity due to high salt or sugar
concentrations seem to propagate 70 vegetatively in the salterns and are thus
halotolerantosmotolerant species rather than simple flush-through occurrences
Cladiosporum herbarum was frequently isolated from hypersaline waters dead and dying
plant material air soil food fruit cereals paint and textiles (Ventosa 2004)
C) Algae
Most of the painted areas in temperature climate became covered with green algae
(Pleurococcus Protococcus and Trentopholia) while under tropical conditions blue green
algae of the genera Oscillatoria and Sytonema predominated (Garg 1995) The main
factors which contribute to the growth of algae on wall paintings are the presence of
moisture in the plaster as well as availability of visible light These conditions are quite
prevalent in the tropical climate but in temperature regions also algal growth on wall
paintings have been reported [Tonolo et al (1961) Pietrini et al (1991)]
D) Actinomycetes
Usually literature refers to specific aspects eg the occurrence of cyanobacteria
and algae in caves with natural openings to sunlight or those with artificial lighting fungi
and so forth Actinomycetes have been considered to be mainly confined to soils where
they find their natural habitat but despite intensive studies there are still many gaps in our
knowledge of the role played by actinomycetes in soil processes and biodegrations of
murals cave paintings (Groth et al 1999) In addition halophilic bacteria actinomycetes
and cyanobacteria are also capable of growing on salt-affected mural paintings
(Karbowska 2003)
Monte and Ferrari (1993) reviewed the mechanisms of biodeterioration in tombs
and underground churches The role of actinomycetes in the deterioration of frescoes in
hypogean environments was stressed by Agarossi et al (1985) Monte and Ferrari (1993)
Giacobini et al (1987) described the serious damage suffered by a whole series of famous
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
32 Review of Literature
frescoes in underground environments Actinomycetes were isolated from these mural
paintings located in crypts caves and tombs About 200 strains of actinomycetes were
isolated 60 of which were identified The most frequent species were Streptomyces albus
S cinereoruber S griseolus S vinaceus and some members of the Nocardia genus
Heterotrophic bacteria and actinomycetes were the most abundant microorganisms
on the frescoes of Etruscan tombs (Agarossi et al 1985) Bettini et al (1977) studied
some of the oldest Etruscan tombs (7th to 4th century BC) and found white-grey patinas
and spots from streptomycetes in the mural paintings They related the biodeterioration to
the microclimatic conditions (eg lower temperatures high RH) Monte and Ferrari (1993)
considered that colonization of the mural paintings was the result of selective competitive
and inhibitory dynamics among different microorganisms under different and changing
environmental conditions The pigments excreted by some actinomycetes were responsible
for the violet stains found on the walls of tombs in Tarquinia Similar stains were observed
in one of the Roman tombs the Circular Mausoleum the Necropolis of Carmona Spain
from which a Streptomyces sp producing violet pigments in culture media was isolated
214 Identification of biodeteriogens
The possibility of pigments and biodeteriogens identification in frescos and stone
monitoring is offered mostly by vibrational spectroscopy infrared thermography laser
induced fluorescence (LIF) laser induced breakdown spectroscopy (LIBS) XRF (X-Ray
Fluorescence) IR and UV emission Among them laser based methods allowing for in
situ or remote characterization of artwork surface were applied successfully for
prospecting diagnosis and maintenance (Colao et al 2005) The rep-PCR fingerprinting
of the isolates allowed determination of their genotypic diversity Studies that have
compared rep-PCR genomic fingerprint analysis with DNAndashDNA relatedness studies have
shown that the two techniques yield results that are in close agreement [Nick et al (1999)
Rademaker et al (2000)] These studies therefore suggest that rep-PCR fingerprinting can
be used as a genomic screening method to differentiate at the species level and to select
representatives for DNAndashDNA reassociation experiments (Heymann et al 2003)
The characterisation of bacteria was for example often limited to isolation from
group-specific media followed by microscopy [Sorlini et al (1987) Weirich (1989)
Tate et al (1990) and in more recent studies to morphological and physiological
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
33 Review of Literature
characteristics including miniaturised and automated systems such as API and BIOLOG
[Arroyo et al (1997) Jimmenez et al (2000) and Laiz et al (2000)] or to
chemotaxonomic characteristics [Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
Wagner et al (1994) demonstrated that conventional microbiological efforts can
fail to isolate all microorganisms present in natural samples DNA-based techniques used
to identify microorganisms have revealed only a smaller fraction of bacteria isolated from
artworks (Ward et al 1990 Rolleke et al 1996) Bacterial identification using molecular
techniques especially those including the sequencing of genes coding for ribosomal
16S rRNA is very important to study bacterial communities found on artefacts One such
method is Denaturing Gradient Gel Electrophoresis (DGGE) of PCR-amplified gene
fragments coding for rRNA (Muyzer et al 1993) that allows the separation of partial
16S rDNA amplified fragments of identical length but different sequence due to their
different melting behaviour in a gel system containing a gradient of denaturants
(Jimenez 2003)
Total genomic DNA was purified for 16S rRNA gene sequencing and rep-PCR
using a slight modification of the method of Pitcher et al (1989) as described by
Heyndrickx et al (1996) rep-PCR genomic fingerprinting was performed with the REP-
and (GTG)5 primers (Versalovic et al 1994) using the PCR conditions described
previously by Rademaker et al (1997) Electrophoresis and pattern analysis were further
performed as described by Heyrman et al (2003) 16S rRNA gene sequencing and
phylogenetic analysis were performed as described by Heyrman and Swings (2001)
Phylogenetic trees were constructed using the BioNumerics software (Applied Maths) by
applying the neighbour-joining and maximum-parsimony methods on a multiple alignment
similarity matrix The stability of relationships was assessed by a bootstrap analysis of
1000 datasets For determination of the G+C content and levels of DNAndashDNA
hybridization approximately 1 g biomass was harvested from agar plates DNA was
purified by using a combination of the protocols of Marmur (1961) and
Pitcher et al (1989) as described by Logan et al (2000) The G+C content of the DNA
was determined by HPLC (Mesbah et al 1989) using the further specifications given by
Logan et al (2000) DNAndashDNA hybridization experiments were performed using a
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
34 Review of Literature
modification of the microplate method of Ezaki et al (1989) as described by
Willems et al (2001)
215 Preservation and conservation
Nowadays the conservation and preservation of our cultural heritage is one of the
world main concerns particularly in Europe The increasing need for non-destructive
investigation tools has become a major issue as sampling is in most cases restricted in
view of the value or the uniqueness of the object Artworks as wall paintings in buildings
and monuments of historical interest are affected by environment physical (temperature
and humidity) and biological factors (biodeteriogens) and by human (pollutant releases)
impact and therefore modified over the time The term ldquoconservationrdquo may have many
different meanings in different fields Every intervention directed to the restoration and
safeguard of works of art is commonly considered as a conservation treatment For
example conservation can involve the cleaning procedures set up by chemists or the photo
documentation of the preservation of historical memory For the appropriate conservation
of works of art even the lighting systems in a museum or the control of the visitorrsquos
movements in a site should be monitored Chemical degradation which induces the flaking
of paintings and deterioration from rain wind dust and other environmental causes is
mainly responsible for the weakening of the porous structure and the surface layers of the
materials used in works of cultural heritage (Colao et al 2005)
216 Conservation history
Wall paintings are an integral part of monuments and sites and should be preserved
in situ Many of the problems affecting wall paintings are linked to the poor condition of
the building or structure its improper use lack of maintenance frequent repairs and
alterations Also frequent restorations unnecessary uncovering and use of inappropriate
methods and materials can result in irreparable damage Substandard and inadequate
practices and professional qualifications have led to unfortunate results It is for this reason
that an appropriate document covering the principles of proper conservation-restoration of
wall paintings is necessary
The Venice Charter (1964) has provided general principles for the conservation-
restoration of cultural heritage The Amsterdam Declaration (1975) introducing the
concept of integrated conservation and the Nara Document on Authenticity (1994) dealing
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
35 Review of Literature
with cultural diversity have expanded these principles Taking into account these and
additional relevant contributions such as the ICOM-CC Code of Ethics (1984) Document
of Pavia (1997) and ECCO Professional Guidelines (1997) the aim of this document is
to provide more specific principles for the protection preservation and the conservation
restoration of wall paintings This document therefore reflects basic and universally
applicable principles and practices and does not take into account particular problems of
regions or countries which can be supplemented at regional and national level by
providing further recommendations where necessary
217 Preservation techniques of the mural paintings
The removal of fat salts varnishes and pollutants from the surfaces of the works
of art are mostly done by chemical and mechanical methods At the end of the 19th
century the practices of restoration methods that do not inhibit further future interventions
was considered acceptable During the 1960s several chemicals such as polymeric resins
were synthesized and applied as a consolidation or protection agents The accepted idea
was that these substances could be removed at any time leaving a completely unaltered
substrate On the basis of origin archaeological objects can be classified as follows
(Carretti 2005)
1 Inorganic It includes siliceous and nonsiliceous materials Archaeological materials
produced from stones terracotta ceramics and glass can be included under siliceous
materials whereas objects made of metals can be included under nonsiliceous inorganic
materials Again metal objects can be classified as ferrous metals and non-ferrous metals
Objects made of iron are termed as ferrous metal objects whereas metal objects made from
other than iron is termed as non-ferrous metal objects
2 Organic It includes archival and anthropological materials Again archival materials
include paper bhojapatra tadapatra textiles wooden objects miniature paintings whereas
anthropological objects include bone and ivory leather feather and fur etc
In the past restoration of paintings and other old artwork often involved application
of acrylic resins to consolidate and protect them One of the most important tasks for
modern restorers is thus to remove these layers because it turns out that acrylic resins not
only by drastically changing the optics of the treated artwork but in many cases they
accelerate their degradation The scientists use an oil-in-water microemulsion with the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
36 Review of Literature
organic solvent para-xylene as the oil component The matrix makes the cleaning agent
viscous so that it cannot enter very far into the pores of a painting (Carretti 2005)
Nanoparticle treatment is the logical evolution of the Ferroni-Dini method
Dispersions of kinetically stable Ca (OH)2 nanoparticles in non-aqueous solvents solved
most of the drawbacks of the microsized powders Stable dispersions of calcium hydroxide
have been successfully applied (replacing polymers) as fixatives to re-adhere lifted paint
layers during many restoration workshops in Italy and in Europe as a consolidant The
FerronindashDini method (two steps the application of a saturated solution of ammonium
carbonate (NH4)2CO3 and the treatment with a barium hydroxide solution Ba(OH)2 also
called the barium method has long been the acknowledged method for the removal of
salts that threaten paintings reinforcing at the same time the porous structure However
commercially available carbonates and hydroxide powders have dimensions of several
micrometres much larger than the pores on the paint surface This means they donrsquot
penetrate the painting well and there is also a risk of damaging the artwork by a white
glaze forming on the surface (Berger 2006) Restoration should provide the reinforcement
of the porous structure and the consolidation of the surface layer of arte facts A few
simple principles can be considered to define the most appropriate restoration method
1) The treatment should be reversible so that one can revert to the original status of the
work of art at any desired time
2) All the applied chemicals must ensure the maximum durability and the chemical
inertness
3) The applied chemicals must invert the degradation processes without altering the
chemical composition of the artefacts and their physico-chemical and mechanical
properties (Baglioni 2006)
218 Commercial preservative used for preservation of mural paintings
Cleaning was done using soft brushes vacuum cleaner and Gumma paine (dough)
a natural latex sponge Areas near the window were very dirty with black soot and were
cleaned with micro fibrous cloths moistened with synperonic N (surfactant alkyl phenol
ethoxylate based on nonyl phenol) and neutralized with clean water In several places the
paint layers had separated from the substrate (exfoli-ation) In that cases loose paint flakes
were stuck back using Paraloid B72 (10 solution in ethanol) as sparingly as possible
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
37 Review of Literature
Paraloid was injected with syringe behind the exfoliated area twice pushed and held back
with Melinex (polyester film) until fixed on the third application (Bionda et al 2002)
In a period of significant growth of molds and intensive efforts to stop the mold
contamination some of the lines of certain paintings were obscured or faded Solutions of
ethanol formalin 91 and Thiabendazole (TBZ) were used but they were not very
effective Para-formaldehyde fumigation was adopted beginning in 1981 to establish an
emergency treatment sensitivity of microorganisms from studied samples was tested
against Desogen by adding 1-3 (v v) in serial dilutions The best concentration
3 (vv) was applied with a brush to prevent spreading of the spores In order to overcome
the problem of fungal attack suitable fungicides carbendizeme or kiroxy-I or 5 solute of
N formaldehyde can be used Shellac solution in spirit or 2 solution of polyvinaycletate
in toluene can be used as preservative and consolidantsTo control insect and fungal attack
fumigants like pyrethrum DDT or 5 solution of sodium penta chlorophenate in kerosene
oil 2 to 5 solution of PVA in toluene or 2 to 5 solution of paraloid B-72 in toluene or
acetone be used (Miura 2009) Microclimatic conditions constitute a critical factor in the
conservation of cave paintings The unstable microclimatic condition is one of the factors
that always affect the state of conservation of mural paintings In the environmental-
monument system knowledge of the functional environment and climatic conditions of the
surroundings are necessary for the identification of causes of decay (Singh 2011)
Furthermore the risk of formation of indoor bioaerosols in residential and public
buildings (offices schools museums etc) has attracted interest in the last years due to
socio-economic as well as sanitary reasons (Ripka 2005) Thus it is important in aspects of
health and maintenance of Cultural Heritage to analyse the complete microflora to further
develop biocides for harmful microorganisms and methods for restoration of damaged
objects of art The biocidal testing was carried out on one representative algal species of
the two classes of algae viz Chlorococcum sp (green) and Chroococcus sp (blue-green)
found to be common in all the samples Efficiency tests were carried out both in liquid as
well as solid media containing algal suspensions by adding a biocide solution of known
concentration and determining the growth of the microorganism after the incubation
period The biocides used for the past studies were
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
18 Review of Literature
survived centuries only on account of the identification and use of those colors which does
not have any reaction with lime (Miraseth 2006)
Originally three types of brushes were made and used flat medium and fine Flat
brushes were made from hairs behind calfrsquos ear the medium from the bottom of goats
belly and the fine brush from delicate blades of grass However in due course of time and
change use of easily available brushes from commercial market and shading of the
original colours can be distinctively noticed The use of blue colour is also noticed over the
passage of time The paintings have been brought down from the walls to plywood cloth
paper and other frames for easy to make and use purposes (Chakarabarti 1980)
27 Themes of mural painting
The subjects and themes in the murals are centered on the Hindu pantheon of Gods
and Goddesses drawn from description in the invocatory verses or Dhyana Slokas More
common representations are of Vishnu in different incarnations Ganesha and
manifestations of Siva We see murals in the Pallimanna Siva Temple devoted to Siva-
Parvatirsquos marriage the Ramayana Story being narrated on the walls of the Mattancheri
palace in the Sankara Narayana the Mahabharata is retold Murals are various scenes from
the Hindu epics and also the frolics of Lord Krishna
It would be interesting to bring into account the influence of the mural paintings on
Christianity On various churches like the St Georgersquos Orthodox Church has Christian
murals bringing out biblical characters and narrating stories from the scriptures Mar
Sabore and Afroth Church at Akapparambu in the outskirts of Ernakulam also have murals
of scenes from the bible Interestingly StMaryrsquos Church at Kanjoor has on both sides of its
entrance a battle scene between the armies of Tipu Sultan and of the English East India
Company It is also apparent that the history of Kerala Murals has its origin in the temple
walls and thus a study of Kerala Murals is not complete without pondering on the
architecture of Kerala its association with the murals (Warrier 2011)
28 Technique used in mural paintings
Indian murals executed on walls of caves structural temples walls of palaces were
based on highly developed techniques Mural painting is a composite structure of these
three basic layers the support the ground and the pigment layer In case of wall painting
the wall itself is the support This is followed by the layer or layers of plaster which
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
19 Review of Literature
constitute the ground The pigment layer is the one which contains the picture The support
is the wall which may be rock surface in a cave or a structural one These stone surfaces
which serve as carriers are rough or uneven This unevenness is itself an advantage as it
provides ldquotoothrdquo to hold the plaster on the surface The uneven surface of the wall has to be
made uniform with layers of plaster in successive gradation of fineness There is generally
one layer of rough plaster followed by one or more layers of fine plaster Ground or plaster
is a term used to mean the surface material of a wall or building which is applied as a
plastic mass made by mixing certain materials with water letting the mass set by drying
carbonation or hydration The active or setting components of plaster are commonly clay
which sets by drying lime which sets by carbonation gypsum and pozzolana which sets by
hydration (Mini 2010)
There are different mixtures for rough plaster In all the mixtures clay limestone
lime and shells in powdered form serve as the matrix The particles of which are held
together by the organic materials like gum glue extracts from barks etc are in fact
adhesives The fine plaster layer requires more careful preparation because it is the layer on
which the pigments are laid to make the picture ldquoShilparatnardquo suggest a mixture of conch
Oyster shells or white clay with gum of neem or slaked lime and coconut water Here the
consolidation is effected by the carbonation of slaked lime ie it absorbs carbon dioxide
from air and becomes carbonate Mural paintings were lime-washed from the 17th until the
beginning of 19th century A few paintings in vaults were never lime-washed for example
at Taby and Floda painted by the medieval painter Albertus Pictor (Mini 2010)
All the paintings have certain basic common characteristics There has to be a wall
or rock surface called support over which the artist goes to work A plaster base called
ground of varied thickness is laid on the support The ground may consist of one or more
layers The strength and life of the whole mural depended up on this ground over which the
painting was done It is the process of applying the final painting on the ground determines
the character of the mural whether it is fresco or tempera The mural painting is done
usually by creating wall surface free of any previous oil or paint by using solvent or by
sand blasting The brick wall is first plastered with mixture of lime and sand in the ratio of
12 A mixture of egg yolk vinegar oil colour is used in dry plaster
There are at least six stages before a Kerala Mural Painting is complete Lekhya
Karma is the first stage where sketching by pencil or crayon is done The second stage is
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
20 Review of Literature
the Rekha Karma which enhances the outlines of the sketching done The third stage called
Varna Karma breathes life into the painting with its colours Here all colours are
appropriately filled in The colouring of the human figures is done according to the
characters and their common virtues The divine and noble characters (Saatvik) are painted
in green those inclined towards power and wealth (Raajasik) is painted in shades of red
lowly mean characters (Tamasik) in white and demons in black In the fourth stage or the
Vartana Karma shading is done Fifth stage called the Lekha Karma brings us to the final
outline of the painting which is usually in black The final and the finishing touches stage
are called Devika Karma (Warrier 2011)
29 Dyes used in mural painting
Indians have been considered as fore runners in the art of natural dyeing Natural
dyes find use in the colouring of textiles drugs cosmetics etc Owing to their non-toxic
effects they are also used for colouring various food products In India there are more
than 450 plants that can yield dyes In addition to their dye-yielding characteristics some
of these plants also possess medicinal value Though there is a large plant resource base
little has been exploited so far Due to lack of availability of precise technical knowledge
on the extracting and dyeing technique it has not commercially succeeded like the
synthetic dyes (Siva 2007)
The color materials on the mural paintings in ancient India were derived from the
natural materials like terracotta chalk red ochre and yellow ochre mixed with animal fat
The dyes for painting is prepared such as white from lime Black from carbon soot of
lamps Red and yellow from minerals Blue from indigo ferra Deep red from lac A fine
coating of resin is done after the painting in order to make a shining appearance Egg yolk
and vinegar was mixed with oil colors and painted on dry plaster (Krishnakumar 1999)
Although plants exhibit a wide range of colours not all of these pigments can be
used as dyes Some do not dissolve in water some cannot be adsorbed onto fibres whereas
others fade when washed or exposed to air or sunlight It remains a mystery why plants
reward us with vibrant dyes India has a rich biodiversity and it is not only one of the
worldrsquos twelve mega diversity countries but also one of the eight major centres of origin
and diversification of domesticated taxa It has approximately 490000 plant species of
which about 17500 are angiosperms more than 400 are domesticated crop species and
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
21 Review of Literature
almost an equal number their wild relatives Thus India harbours a wealth of useful
germplasm resources and there is no doubt that the plant kingdom is a treasure-house of
diverse natural products One such product from nature is the dye (Siva 2007)
Many natural dyestuff and stains were obtained mainly from plants and dominated
as sources of natural dyes producing different colours like red yellow blue black brown
and a combination of these Almost all parts of the plants like root bark leaf fruit wood
seed flower etc produce dyes It is interesting to note that over 2000 pigments are
synthesized by various parts of plants of which only about 150 have been commercially
exploited Nearly 450 taxa are known to yield dyes in India alone of which 50 are
considered to be the most important ten of these are from roots four from barks five from
leaves seven from flowers seven from fruits three from seeds eight from wood and three
from gums and resins Some important dye-yielding plant habitats their distribution and
colouring pigment (Siva 2007)
The dye is generally prepared by boiling the crushed powder with water but
sometimes it is left to steep in cold water The solution then obtained is used generally to
dye coarse cotton fabrics Alum is generally used as a mordant Flowers of Butea
monosperma (Lam) Taubert yield an orange-coloured dye which is not fast and is easily
washed away For the purpose of colouring the material is steeped in a hot or cold
decoction of the flowers A more permanent colour is produced either by first preparing the
cloth with alum and wood ash or by adding these substances to the dye-bath The dye
indigo is produced by steeping the plant in water and allowing it to ferment This is
followed by oxidation of the solution with air in a separate vessel Mallotus philippinensis
muell yields an orange colour used for dyeing silk and wool To prepare the annatto dye
from B orellena the fruits are collected when nearly ripe The seeds and pulp are removed
from the mature fruit and macerated with water Thereafter they are either ground up into
an lsquoannatto pastersquo or dried and marketed as annatto seeds Sometimes when the seeds and
pulp are macerated with water the product is stained through a sieve and the colouring
matter which settles out is collected and partially evaporated by heat and finally dried in
the sun (Sowbhagya 2002)
The predominant colors used in rock art and cave art are black (from charcoal soot
or manganese oxide) yellow ochre (limonite) red ochre (hematite or baked limonite) and
white (kaolin clay burnt shells powdered gypsum or powdered calcium carbonate) All of
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
22 Review of Literature
theses pigments may be used on leather or raw hide as well Early cave art in Seminole
Canyon was monochromatic in red and as culture grew more sophisticated the color
palette expanded Blue Orange Brown Green and Purple are the most common colours
used in Ajantha murals White Pink Gold are occasionally represented mineral earths
containing ferric oxide and copper carbonates were used as source of red yellow and green
colours There is also evidence to establish that root of Rubia cardifolia and leaves of
Indigofera tinctoria were used as source for red and blue colours (Nayer et al 1999)
Many colors of pigments were obtained from both organic and inorganic sources in
ancient times and used to paint various surfaces such as braintan leather clothing and
accoutrements rawhide the human body etc Blue color was obtained from powdered
azurite and lapis duck manure and certain clays Fine Blue-green clay was obtained from
deposits near Mankato Michigan Organic sources of blue include Turkeys Tail a
greenish blue polypore that grows on dead decaying wood (not tannish ones) Native
Americans get Indigo from either Guatemala or Ecuador which was traded well up onto
Kansas long before the Spanish ever set foot here American Indigo has purple tones to it
but IndianJapanese indigo has green tones Berries and crushed flowers were also used to
obtain blue color by rubbing the plant material directly on the leather
An organic source of red was Cochineal It was native west of the Mississippi and
is produced from the bodies of small insects that grow on the prickly pear cactus Ladys
Bedstraw gives a good vermillion red color Harvest the roots dry them out clean the mud
etc off of them and then grind the roots really fine then soak them to extract the red
coloring The key here is drying the root first Blood was also used as red pigment Pucoon
roots also yield a red pigment (Smith 2002) Red ochre the reverse original red colours are
due to variations in iron oxide (or) calcite content and to redox conditions in the firing
produced Brown coloured ceramics owe their colour to maghemite and must be
considered as a fabrication defect due to the position of the ceramic piece in a zone where a
reducing atmosphere prevailed in the course of firingRed pigments were produced from
iron oxides like hematite or limonite and from ochre Hematite was the most frequently
used mineral It occurs in the form of aggregates of small red crystals or in the form of
bigger black crystals which are difficult to crush white was obtained mostly from
kaolinite or illite (Clottes et al 1990)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
23 Review of Literature
210 Biodetoriation of mural paintings
Historic items often contain natural biodegradable materials and have histories of
exposure to moist conditions These two conditions make them amenable to microbial
attack Microbial colonization may damage the building or the cultural asset
(Salonen 2001) Biodeteriogens are organisms involved in deterioration of artifacts They
are very specific for each type of artifact in accordance with its chemical structure and
environment They also have different nutritional requirements and act directly or
indirectly on the substrate The adhesion of microorganisms to a substrate is the result of
cell hydrophobicity and of excreted polymeric substances contained by sheaths capsules
and slimes (Colao 2005)
The surviving wall paintings and decorations in subterranean environments around
Malta are rather scarce (Buhagiar 1986 1993 1998) These include those at St Paulrsquos
Catacombs (Zammit 2008) St Agatharsquos Crypt and Catacombs (Camilleri 2001)
San Catald Catacombs Tac-Cghaqi Abbatija tad-Dejr (Buhagiar 1993) all in Rabat the
cave-sanctuary in Mellieħa (Buhagiar 1987) and the Ħal Saflieni Hypogeum in Paola
(Pace 2000) Previous studies conducted on wall paintings and decorations in Maltese
Palaeo-Christian Catacombs have involved their manufacturing techniques (Muscat 2005)
However to date limited systematic studies have been conducted into the biodeterioration
in Maltese Palaeo- Christian Catacombs The only such studies ever conducted in Malta
concerned the biodeterioration of works of art in catacombs have been carried out at St
Agatharsquos Crypt and Catacombs in Rabat (Zammit et al 2008 Psaila 2006)
Microorganisms can be responsible for the destruction of monuments buildings
and cultural heritage assets including the decay of concrete cement stones mural
paintings etc These microorganisms are not only related with biodeterioration but water-
damaged indoor building materials are frequently colonized by complex bacterial
communities and may emit mixed bioaerosols into the indoor air (Jimenez 2000) It is
well known that mural paintings are colonized by micro-organisms and can be severely
damaged by such growths (Ciferri 1999) A large number of fungal (gt50) and bacterial
taxa (70) have been detected in indoor environments Over 50 bacterial species and 14
genera novel to science were reported in the past 10 years from indoor air and historic
items indicating bacterigravea in these enviroments are as yet only fragmentarily known
(Salonen 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
24 Review of Literature
Traditionally the study of microflora which causes this biodeterioration was based
on classical cultivation methods that were mainly useful to study the physiological
potential of microorganisms but do not provide information on all microbial communities
to be found in excavated artifacts Indeed many studies using culture-independent
techniques which cultivate microorganisms from different environments may often
represent only minor components of the microbial community as a whole It is generally
accepted that cultivation methods recover less than 1 of the total microorganisms present
in environmental samples (Ward et al 1990 Amann et al 1995) Hence microbial
investigations based only on cultivation strategies cannot be regarded as reliable in terms
of reflecting the microbial diversity present in objects of art (Osburn et al 2011)
Early workers suggested that the presence of living microorganisms on stone
increased its susceptibility to damage through their water-binding capacity It has recently
been reported that the mineralogy porosity surface roughness and capacity to collect
water and organic materials control its bioreceptivity and tendency to biodeterioration
(Diakumaku 1995) In addition environmental factors as temperature light pH and
relative humidity affect the number and type of colonising species (Tiano et al 1995) and
hence the progress of colonisation Biofilms on decayed stones consist on mixed microbial
populations embedded in a polymeric matrix Fungi algae filamentous and unicellular
bacteria are found in these complex communities A variety of bacteria have been isolated
from different stone samples confirming the dominance of Gram-positive organisms
especially spore-forming bacteria such as Bacillus and filamentous actinomycetes
(Ripka 2005)
In cultivation studies of deteriorated mural and rock paintings bacterial isolates
have frequently been attributed to the genus Bacillus (Weirich 1989 Tate and Rebrikova
1991 Gonzalez et al 1999 Heyrman et al 1999 Jimenez et al 2000) Other studies that
have included DNA-based techniques to characterize the bacterial community involved in
biodeterioration have shown that a substantial part of the bacterial population is made up of
so far unknown species (Altenburger et al 1996 Rolleke et al 1996 Gurtner et al 2000
Heyrman and Swings 2001) (Heymann et al 2003)
Many potential mycotoxin producers have been detected in air and items from
indoor environments with histories of exposure to moisture for example species of
Acremonium Alternaria Aspergillus Chateomium Fusarium Eurotium Paecilomyces
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
25 Review of Literature
Penicillium Scopulariopsis Stachybotrys Trichoderma Verticillium and Wallemia
(Peltola et al 2001 Pieckova et al 2001) Not all strains of one species produce
mycotoxins and different strains may produce different toxins Whereas toxin producing
strains are frequent in crops and outdoor vegetation toxin producing isolates from indoor
environments and non living assets have only been reported of the species Aspergillus
versicolor (Nielsen et al 1998) Stachybotrys chartarum Nikulin (1997) and
Trichoderma harzianum (Peltola et al 2001) Streptomyces griseus strains producing
valinomycin occur in environments where humans can get exposed
(Andersson et al 2002) The biological properties and toxicity mechanisms of cereulide
were identical to those by valinomycin (Mikkola et al 1999 Salonen et al 2001)
The genus Paenibacillus was first proposed by Ash et al (1993) and its description
was emended by Shida et al (1997) The genus Paenibacillus is under intensive taxonomic
investigation with ten species having been formally described in the last year Heyrman amp
Swings (2001) isolated a strain originally classified as Paenibacillus sp LMG 19508
from biodeteriorated mural paintings in the Servilia tomb at the Roman necropolis of
Carmona in Seville Spain (Smerda et al 2006) Building stone and wall paintings contain
a variety of hydroscopic salts including carbonates chlorides nitrates sulfates etc
dispersed within the porous material or locally concentrated These salts are solubilised
and migrate with the water in and out of the stone Due to changes in physical parameters
the so called salt efflorescences appear on the surfaces providing extremely saline
environments and building niches for settlement of halophilic microorganisms Halite and
other hygroscopic salts can retain considerable quantities of moisture when entrapped in
the building materials and thus favouring the bacterial growth (Ripka 2005)
It is demonstrated that water-damaged indoor building materials contained
substances of microbial origin extremely toxic to eukaryotic cells and large quantities of
several microbial species known to be potentially toxic or immunopotentiating These
include peptidoglycans Gram-negative endotoxin β-13-D glucans lipoglycans and
teichoic acids and mycotoxins (Jimenez 2000) In turn these microorganisms can mediate
the crystallization process These crystallizations can produce destructive effects Some
salts may crystallize or recrystallize to different hydrates which occupy a larger space and
exert additional pressure producing cracking powdering and flaking
(Jimenez and Laiz 2000)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
26 Review of Literature
211 Types of deterioration on mural paintings
The frescos represent a variety of ecological niches where primary colonization is
due to photoautotrophic and chemolithoautotrophic microorganisms followed by
secondary colonization due to heterotrophic bacteria that obtain nutrients from various
sources (metabolites of autotrophic bacteria airborne organic contamination animal faeces
and organic compounds in the paint layers themselves) Microbial-induced deterioration
processes cause structural as well as aesthetic damage to wall paintings such as the
discoloration of materials the formation of crusts on surfaces and the loss of material
(Sarro et al 2006 Osburn et al 2011) Halophilic bacteria and archaea were thought to
be found only in extreme environments like salt lakes or black smokers However it has
been shown that mural paintings and stones are a common habitat for extremely salt
tolerant and moderate halophilic (Ripka 2005) Microbial induced deterioration processes
can cause different kinds of alterations such as discolouration of materials the formation of
crusts on surfaces and the loss of material which leads to structural damage (Ripka 2005)
First of all microorganisms can cause severe problems due to the excretion of aggressive
metabolic products such as organic or inorganic acids Secondly material components can
be used as substrates for microbial metabolism Exoenzymes such as cellulases proteases
tannases beta-glucosidase produced by fungi and bacteria are responsible for hydrolysis of
cellulose and proteins Further examples are mechanical processes caused by swelling and
shrinking of slime or mycelia penetrating inside plaster of the painting resulting in loss of
cohesion and detachment of the paint layer (Rolleke 1996 Gurtner et al 2000)
Table-21 Microbial damage on mural paintings (Rolleke 1996)
S No Damage Microbial activity
1 Green brown red grey
surface layers (patinas)
Pigments produced by microorganisms (intra-or
extracellular) as chlorophyll and carotinoids
2 Dislodging of painting layers Use of organic binders as nutrient and energy
source
3 Acid attack of carbonates Acid produced by fungi or bacteria
4 Discolouration of pigments Redox-reactions induced by fungi and
bacteria
5 Loss of paint layer Growth of microorganisms deep into the plaster
6 Hydrolysis of synthetic
polymers Chemoorganotrophic activity of bacteria and fungi
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
27 Review of Literature
Discolorations are caused by excretion of pigments and microbiologically induced
reductionoxidation-processes (Krumbein et al 1990) Degradation of the bindings is
followed by reduction of stability Oxidation of ammonium and reduced sulphur
compounds results in acidification of the environment such as Sulphuric acid and the
variety of organic acids produced by the heterotrophs cause solubilization of calcareous
binding material and chelation of metal ions (Bock et al 1993) It is now well recognised
that wall paintings can be deteriorated by microorganisms (Ciferri 1999)The growth of
microorganisms essentially results in two types of damage aesthetic and structural
Aesthetic damage implies pigment discoloration stains and formation of a biofilm on the
painted surface Structural damage is observed as cracking and disintegration of the paint
layer formation of paint blisters and degradation of support polymers or of glues and
binders resulting in detachment of paint layer from the support The colonization of mural
paintings by bacteria and other microorganisms can have different causes Provided that
favorable environmental conditions occur nutrients for heterotrophic bacteria and fungi
can be available from metabolites of autotrophic bacteria from airborne contamination and
dripping water from animal faeces but also from organic compounds in the paint layer
itself
212 Methods of studying biodeterioration
It is now well recognized that wall paintings may be deteriorated by
microorganisms as established by several studies that linked the observed damage with the
microbial community present as reviewed by Ciferri (1999) Despite this knowledge a
reliable characterization of bacteria associated with such damage is often lacking To
obtain greater insight into the bacterial community involved in biodeterioration of mural
paintings three sites (from the necropolis at Carmona Spain and the Saint-Catherine
chapel of the castle at Herberstein Austria) were sampled In previous studies from these
sites 385 isolates were analysed by fatty acid methyl ester GC and representatives of
different fatty acid clusters were further studied by 16S rRNA gene sequencing
(Heyrman and Swings 2001) Several of these representative strains showed the highest
sequence similarity with members of the genus Arthrobacter (Heyrman et al 2005)
Jimenez and Samson (1981) analysed the microbial flora of a large fresco painted
in the late 1920s in the monastery ldquoSanta Maria de la Rabidardquo (Huelva Spain) exhibiting
two types of deterioration white efflorescence and green-to-black stains
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
28 Review of Literature
Tate and Rebrikova (1990) thought autotrophic nitrifying bacteria to be the first colonisers
of damaged frescoes and building materials in the cathedral of the nativity of the Virgin in
the Pafnutii-Borovskii monastery (Russia) The bulk of research on biodeterioration of
mural paintings has focused on explaining the observed phenomena by analysing the
microflora present Following this approach a precise characterisation of the
microorganisms using a polyphasic approach was never the first goal
Only a few studies included genomic fingerprinting (16S rDNA sequence analysis)
for the characterisation of bacteria associated with damage on mural paintings
[Rolleke (1996) Pinar et al (2001)] Previous studies based on culture-dependent
techniques showed that the flora present on frescos are fungi (predominant species of
Penicillium Aspergillus Cladosporium and Engyodontium) (Guglielminetti et al 1994)
bacteria (predominant species of Bacillus Arthrobacter Micrococcus Streptomyces and
Pseudomonas) (Heyrman et al 1999) cyanobacteria and eukaryotic algae (species of
Nostoc Lyngbya and Chlorophyceae) (Arino et al 1996 Calvo et al 1993) The killing
effect of an antimicrobial agent on a microorganism can be assessed in several ways
(1) Lethal activity may be expressed as the rate of killing by a fixed concentration
of drug under controlled conditions This rate is determined by measuring the number of
viable bacteria at various time intervals The resulting graphic depiction is known as the
time-kill curve Bacterial killing rates are in part dependent on the class of antibiotic and
the concentration of this agent With certain classes of antibiotics (eg aminoglycosides
and fluoroquino-lones) the rate of killing increases with increased drug concentrations up
to a point of maximum effect This is termed concentration-dependent bactericidal activity
In contrast the killing rates of szlig-lactam agents and vancomycin are relatively slow and
continue only as long as the concentrations are in excess of the MIC This rate of killing is
termed time-dependent bactericidal activity
(2) The minimal concentration of drug needed to kill most of the viable organisms
after incubation for a fixed length of time (generally 24 hours) under a given set of
conditions is the most common estimation of bactericidal activity and is known as either
the minimal bactericidal concentration (MBC) or the minimal lethal concentration (MLC)
It will be referred to in this document as the MBC Unfortunately the definition of the
MBC (999 killing of the final inoculum) is somewhat arbitrary and separates the
bacteria into two populations ndash a segrega-tion which might not have biological relevance
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
29 Review of Literature
The determination of the MBC moreover is so subject to methodologic variables that the
clinical relevance of MBCs is nearly impossible to assess particularly for certain pathogen
and drug combinations (eg Staphylococci and beta-lactam agents)
(3) The serum of a patient receiving an antibiotic may be tested against the
infecting microorganism This can be done using time-kill curve methodology (ie serum
bactericidal rate) or using dilution methodology (ie serum bactericidal titer) The
principles of these methods as well as the influence of biological and technical factors are
similar (Barry et al 1999)
213 Microbial flora associated with deteriorated mural paintings
A great deal of research has been done in this field mainly by using cultivation dependent
methods However by using culture-dependent methods only a very small proportion of
microorganisms can be obtained Far less than 1 of organisms in the environment can be
cultivated by standard cultivation techniques (Pace 1996) Recent studies have shown that
culture-dependent techniques yielded mainly sporeforming bacteria suggesting that plating
leads to an over estimation of the number of spore-forming bacteria A wide number of
investigations have shown that in addition to chemical and physical processes
microorganisms play a major role in degradation of objects of art such as paintings stone-
works wood paper masonry leather parchment glass and metal (Ripka 2005)
A) Bacteria
In general growth of diverse organisms on mural paintings is supported by
humidity slight alkaline pH values and the presence of organic and inorganic nutrient
sources (Weirich 1989) In mural paintings pigments are suspended in water or oil often
binders such as casein and milk are used and they are supplied on the damp lime plaster
(Ciferri 1999) The calcium carbonate formed on contact with air consolidates the
pigments Thus frescos contain mainly inorganic components While chemoautotrophic
nitrifiers and thiobacilli obtain their energy for growth by oxidizing ammonium and
reducing sulphur-compounds respectively heterotrophic bacteria and fungi depend on
organically bound carbon [Tate et al (1991) Lazar (1971) Petushkova et al (1986)
Jimenez et al (1981)] Thus primary colonization of photoautotrophic Cyanobacteria
chemolithoautotrophic nitrifying bacteria and sulphuric acid producing thiobacilli represent
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
30 Review of Literature
the first supply of organic matter The death and lysis of such bacteria promotes the
secondary settlement of heterotrophic bacteria and fungal populations (Calvo et al 1991)
Bacteria may derive from plants or pollen as many sequences obtained in this study
gave high score similarities with bacteria isolated from plants like Moraxella osloensis
Enterobacter cloace Enterobacter agglomerans and Pantoea endophytica Bacteria may
also derive from animal faeces like flies Bacillus Pseudomonas Aeromonas and Panteoa
(Ripka 2005) As Lazar and Dumitru (1973) reported studying mural paintings in a
Romanian monastery the genera Bacillus Arthrobacter and Pseudomonas have been
proved to produce salt efflorescences and were even considered to cause the blanching
phenomenon of frescoes (Jimenez et al 2000) Predominant bacterial genera are Bacillus
Streptomyces Arthrobacter Micrococcus and Pseudomonas [Weirich (1989)
Tate et al (1990) Arroyo et al (1997) Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
B) Fungi
It may be concluded that there is wide variety of fungal forms present on mural
paintings but Aspergillus and Alternaria were found dominating from all the experimental
sites next to them were Cladosporium Drechestera Fusarium Curvularia Chaetomium
Memnoniella Mycelia sterelai Pencillium Emericella Stachybotrytis Trichoderma
Phoma Monodictys Humicola and Epicoccum (Garg et al 1995)
The fungal genera most commonly found in lists of isolated taxa given in literature
are Alternaria Aspergillus Chaetomium Cladosporium Fusarium Penicillium and
Verticullum [Weirich (1989) Tate et al (1990) Guglielminetti et al (1994)
Garg et al (1995) Berner et al (1997) Ciferri (1999)] Some fungi having hard fruiting
bodies represented by sclerotia pycnidia perithecia cleistothecia and stroma could
organize themselves inside the painted layer Many fungal forms having such structures
were identified from our experimental sites viz Emericella nidulans A flavus
Chaetomium sp and Phoma sp etc These structures with little increase in humidity may
cause swelling in the paint film (Garg 1995)
Strains of species of Alternaria and Cladosporium both of them identified on the
mural paintings of the Palace of Schoumlnbrunn are the most common genera isolated from
stone and mural paintings in indoor environments with standard cultivation methods
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
31 Review of Literature
(Ventosa 2004) Saprophytic species of the genus Cladosporium are among the most
abundant fungi isolated in saltern samples Commonly isolated Cyanobacteria belong to
Nostoc and eukaryotic algae to Lyngbya and members of the Chlorophyceae such as
Chlorella Pseudococcomyxa and Pseudopleurococcus [Gorbushina et al (1987)
Calvo et al (1993) Arino et al (1996)]
They grow optimally on media with low water activity due to high salt or sugar
concentrations seem to propagate 70 vegetatively in the salterns and are thus
halotolerantosmotolerant species rather than simple flush-through occurrences
Cladiosporum herbarum was frequently isolated from hypersaline waters dead and dying
plant material air soil food fruit cereals paint and textiles (Ventosa 2004)
C) Algae
Most of the painted areas in temperature climate became covered with green algae
(Pleurococcus Protococcus and Trentopholia) while under tropical conditions blue green
algae of the genera Oscillatoria and Sytonema predominated (Garg 1995) The main
factors which contribute to the growth of algae on wall paintings are the presence of
moisture in the plaster as well as availability of visible light These conditions are quite
prevalent in the tropical climate but in temperature regions also algal growth on wall
paintings have been reported [Tonolo et al (1961) Pietrini et al (1991)]
D) Actinomycetes
Usually literature refers to specific aspects eg the occurrence of cyanobacteria
and algae in caves with natural openings to sunlight or those with artificial lighting fungi
and so forth Actinomycetes have been considered to be mainly confined to soils where
they find their natural habitat but despite intensive studies there are still many gaps in our
knowledge of the role played by actinomycetes in soil processes and biodegrations of
murals cave paintings (Groth et al 1999) In addition halophilic bacteria actinomycetes
and cyanobacteria are also capable of growing on salt-affected mural paintings
(Karbowska 2003)
Monte and Ferrari (1993) reviewed the mechanisms of biodeterioration in tombs
and underground churches The role of actinomycetes in the deterioration of frescoes in
hypogean environments was stressed by Agarossi et al (1985) Monte and Ferrari (1993)
Giacobini et al (1987) described the serious damage suffered by a whole series of famous
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
32 Review of Literature
frescoes in underground environments Actinomycetes were isolated from these mural
paintings located in crypts caves and tombs About 200 strains of actinomycetes were
isolated 60 of which were identified The most frequent species were Streptomyces albus
S cinereoruber S griseolus S vinaceus and some members of the Nocardia genus
Heterotrophic bacteria and actinomycetes were the most abundant microorganisms
on the frescoes of Etruscan tombs (Agarossi et al 1985) Bettini et al (1977) studied
some of the oldest Etruscan tombs (7th to 4th century BC) and found white-grey patinas
and spots from streptomycetes in the mural paintings They related the biodeterioration to
the microclimatic conditions (eg lower temperatures high RH) Monte and Ferrari (1993)
considered that colonization of the mural paintings was the result of selective competitive
and inhibitory dynamics among different microorganisms under different and changing
environmental conditions The pigments excreted by some actinomycetes were responsible
for the violet stains found on the walls of tombs in Tarquinia Similar stains were observed
in one of the Roman tombs the Circular Mausoleum the Necropolis of Carmona Spain
from which a Streptomyces sp producing violet pigments in culture media was isolated
214 Identification of biodeteriogens
The possibility of pigments and biodeteriogens identification in frescos and stone
monitoring is offered mostly by vibrational spectroscopy infrared thermography laser
induced fluorescence (LIF) laser induced breakdown spectroscopy (LIBS) XRF (X-Ray
Fluorescence) IR and UV emission Among them laser based methods allowing for in
situ or remote characterization of artwork surface were applied successfully for
prospecting diagnosis and maintenance (Colao et al 2005) The rep-PCR fingerprinting
of the isolates allowed determination of their genotypic diversity Studies that have
compared rep-PCR genomic fingerprint analysis with DNAndashDNA relatedness studies have
shown that the two techniques yield results that are in close agreement [Nick et al (1999)
Rademaker et al (2000)] These studies therefore suggest that rep-PCR fingerprinting can
be used as a genomic screening method to differentiate at the species level and to select
representatives for DNAndashDNA reassociation experiments (Heymann et al 2003)
The characterisation of bacteria was for example often limited to isolation from
group-specific media followed by microscopy [Sorlini et al (1987) Weirich (1989)
Tate et al (1990) and in more recent studies to morphological and physiological
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
33 Review of Literature
characteristics including miniaturised and automated systems such as API and BIOLOG
[Arroyo et al (1997) Jimmenez et al (2000) and Laiz et al (2000)] or to
chemotaxonomic characteristics [Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
Wagner et al (1994) demonstrated that conventional microbiological efforts can
fail to isolate all microorganisms present in natural samples DNA-based techniques used
to identify microorganisms have revealed only a smaller fraction of bacteria isolated from
artworks (Ward et al 1990 Rolleke et al 1996) Bacterial identification using molecular
techniques especially those including the sequencing of genes coding for ribosomal
16S rRNA is very important to study bacterial communities found on artefacts One such
method is Denaturing Gradient Gel Electrophoresis (DGGE) of PCR-amplified gene
fragments coding for rRNA (Muyzer et al 1993) that allows the separation of partial
16S rDNA amplified fragments of identical length but different sequence due to their
different melting behaviour in a gel system containing a gradient of denaturants
(Jimenez 2003)
Total genomic DNA was purified for 16S rRNA gene sequencing and rep-PCR
using a slight modification of the method of Pitcher et al (1989) as described by
Heyndrickx et al (1996) rep-PCR genomic fingerprinting was performed with the REP-
and (GTG)5 primers (Versalovic et al 1994) using the PCR conditions described
previously by Rademaker et al (1997) Electrophoresis and pattern analysis were further
performed as described by Heyrman et al (2003) 16S rRNA gene sequencing and
phylogenetic analysis were performed as described by Heyrman and Swings (2001)
Phylogenetic trees were constructed using the BioNumerics software (Applied Maths) by
applying the neighbour-joining and maximum-parsimony methods on a multiple alignment
similarity matrix The stability of relationships was assessed by a bootstrap analysis of
1000 datasets For determination of the G+C content and levels of DNAndashDNA
hybridization approximately 1 g biomass was harvested from agar plates DNA was
purified by using a combination of the protocols of Marmur (1961) and
Pitcher et al (1989) as described by Logan et al (2000) The G+C content of the DNA
was determined by HPLC (Mesbah et al 1989) using the further specifications given by
Logan et al (2000) DNAndashDNA hybridization experiments were performed using a
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
34 Review of Literature
modification of the microplate method of Ezaki et al (1989) as described by
Willems et al (2001)
215 Preservation and conservation
Nowadays the conservation and preservation of our cultural heritage is one of the
world main concerns particularly in Europe The increasing need for non-destructive
investigation tools has become a major issue as sampling is in most cases restricted in
view of the value or the uniqueness of the object Artworks as wall paintings in buildings
and monuments of historical interest are affected by environment physical (temperature
and humidity) and biological factors (biodeteriogens) and by human (pollutant releases)
impact and therefore modified over the time The term ldquoconservationrdquo may have many
different meanings in different fields Every intervention directed to the restoration and
safeguard of works of art is commonly considered as a conservation treatment For
example conservation can involve the cleaning procedures set up by chemists or the photo
documentation of the preservation of historical memory For the appropriate conservation
of works of art even the lighting systems in a museum or the control of the visitorrsquos
movements in a site should be monitored Chemical degradation which induces the flaking
of paintings and deterioration from rain wind dust and other environmental causes is
mainly responsible for the weakening of the porous structure and the surface layers of the
materials used in works of cultural heritage (Colao et al 2005)
216 Conservation history
Wall paintings are an integral part of monuments and sites and should be preserved
in situ Many of the problems affecting wall paintings are linked to the poor condition of
the building or structure its improper use lack of maintenance frequent repairs and
alterations Also frequent restorations unnecessary uncovering and use of inappropriate
methods and materials can result in irreparable damage Substandard and inadequate
practices and professional qualifications have led to unfortunate results It is for this reason
that an appropriate document covering the principles of proper conservation-restoration of
wall paintings is necessary
The Venice Charter (1964) has provided general principles for the conservation-
restoration of cultural heritage The Amsterdam Declaration (1975) introducing the
concept of integrated conservation and the Nara Document on Authenticity (1994) dealing
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
35 Review of Literature
with cultural diversity have expanded these principles Taking into account these and
additional relevant contributions such as the ICOM-CC Code of Ethics (1984) Document
of Pavia (1997) and ECCO Professional Guidelines (1997) the aim of this document is
to provide more specific principles for the protection preservation and the conservation
restoration of wall paintings This document therefore reflects basic and universally
applicable principles and practices and does not take into account particular problems of
regions or countries which can be supplemented at regional and national level by
providing further recommendations where necessary
217 Preservation techniques of the mural paintings
The removal of fat salts varnishes and pollutants from the surfaces of the works
of art are mostly done by chemical and mechanical methods At the end of the 19th
century the practices of restoration methods that do not inhibit further future interventions
was considered acceptable During the 1960s several chemicals such as polymeric resins
were synthesized and applied as a consolidation or protection agents The accepted idea
was that these substances could be removed at any time leaving a completely unaltered
substrate On the basis of origin archaeological objects can be classified as follows
(Carretti 2005)
1 Inorganic It includes siliceous and nonsiliceous materials Archaeological materials
produced from stones terracotta ceramics and glass can be included under siliceous
materials whereas objects made of metals can be included under nonsiliceous inorganic
materials Again metal objects can be classified as ferrous metals and non-ferrous metals
Objects made of iron are termed as ferrous metal objects whereas metal objects made from
other than iron is termed as non-ferrous metal objects
2 Organic It includes archival and anthropological materials Again archival materials
include paper bhojapatra tadapatra textiles wooden objects miniature paintings whereas
anthropological objects include bone and ivory leather feather and fur etc
In the past restoration of paintings and other old artwork often involved application
of acrylic resins to consolidate and protect them One of the most important tasks for
modern restorers is thus to remove these layers because it turns out that acrylic resins not
only by drastically changing the optics of the treated artwork but in many cases they
accelerate their degradation The scientists use an oil-in-water microemulsion with the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
36 Review of Literature
organic solvent para-xylene as the oil component The matrix makes the cleaning agent
viscous so that it cannot enter very far into the pores of a painting (Carretti 2005)
Nanoparticle treatment is the logical evolution of the Ferroni-Dini method
Dispersions of kinetically stable Ca (OH)2 nanoparticles in non-aqueous solvents solved
most of the drawbacks of the microsized powders Stable dispersions of calcium hydroxide
have been successfully applied (replacing polymers) as fixatives to re-adhere lifted paint
layers during many restoration workshops in Italy and in Europe as a consolidant The
FerronindashDini method (two steps the application of a saturated solution of ammonium
carbonate (NH4)2CO3 and the treatment with a barium hydroxide solution Ba(OH)2 also
called the barium method has long been the acknowledged method for the removal of
salts that threaten paintings reinforcing at the same time the porous structure However
commercially available carbonates and hydroxide powders have dimensions of several
micrometres much larger than the pores on the paint surface This means they donrsquot
penetrate the painting well and there is also a risk of damaging the artwork by a white
glaze forming on the surface (Berger 2006) Restoration should provide the reinforcement
of the porous structure and the consolidation of the surface layer of arte facts A few
simple principles can be considered to define the most appropriate restoration method
1) The treatment should be reversible so that one can revert to the original status of the
work of art at any desired time
2) All the applied chemicals must ensure the maximum durability and the chemical
inertness
3) The applied chemicals must invert the degradation processes without altering the
chemical composition of the artefacts and their physico-chemical and mechanical
properties (Baglioni 2006)
218 Commercial preservative used for preservation of mural paintings
Cleaning was done using soft brushes vacuum cleaner and Gumma paine (dough)
a natural latex sponge Areas near the window were very dirty with black soot and were
cleaned with micro fibrous cloths moistened with synperonic N (surfactant alkyl phenol
ethoxylate based on nonyl phenol) and neutralized with clean water In several places the
paint layers had separated from the substrate (exfoli-ation) In that cases loose paint flakes
were stuck back using Paraloid B72 (10 solution in ethanol) as sparingly as possible
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
37 Review of Literature
Paraloid was injected with syringe behind the exfoliated area twice pushed and held back
with Melinex (polyester film) until fixed on the third application (Bionda et al 2002)
In a period of significant growth of molds and intensive efforts to stop the mold
contamination some of the lines of certain paintings were obscured or faded Solutions of
ethanol formalin 91 and Thiabendazole (TBZ) were used but they were not very
effective Para-formaldehyde fumigation was adopted beginning in 1981 to establish an
emergency treatment sensitivity of microorganisms from studied samples was tested
against Desogen by adding 1-3 (v v) in serial dilutions The best concentration
3 (vv) was applied with a brush to prevent spreading of the spores In order to overcome
the problem of fungal attack suitable fungicides carbendizeme or kiroxy-I or 5 solute of
N formaldehyde can be used Shellac solution in spirit or 2 solution of polyvinaycletate
in toluene can be used as preservative and consolidantsTo control insect and fungal attack
fumigants like pyrethrum DDT or 5 solution of sodium penta chlorophenate in kerosene
oil 2 to 5 solution of PVA in toluene or 2 to 5 solution of paraloid B-72 in toluene or
acetone be used (Miura 2009) Microclimatic conditions constitute a critical factor in the
conservation of cave paintings The unstable microclimatic condition is one of the factors
that always affect the state of conservation of mural paintings In the environmental-
monument system knowledge of the functional environment and climatic conditions of the
surroundings are necessary for the identification of causes of decay (Singh 2011)
Furthermore the risk of formation of indoor bioaerosols in residential and public
buildings (offices schools museums etc) has attracted interest in the last years due to
socio-economic as well as sanitary reasons (Ripka 2005) Thus it is important in aspects of
health and maintenance of Cultural Heritage to analyse the complete microflora to further
develop biocides for harmful microorganisms and methods for restoration of damaged
objects of art The biocidal testing was carried out on one representative algal species of
the two classes of algae viz Chlorococcum sp (green) and Chroococcus sp (blue-green)
found to be common in all the samples Efficiency tests were carried out both in liquid as
well as solid media containing algal suspensions by adding a biocide solution of known
concentration and determining the growth of the microorganism after the incubation
period The biocides used for the past studies were
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
19 Review of Literature
constitute the ground The pigment layer is the one which contains the picture The support
is the wall which may be rock surface in a cave or a structural one These stone surfaces
which serve as carriers are rough or uneven This unevenness is itself an advantage as it
provides ldquotoothrdquo to hold the plaster on the surface The uneven surface of the wall has to be
made uniform with layers of plaster in successive gradation of fineness There is generally
one layer of rough plaster followed by one or more layers of fine plaster Ground or plaster
is a term used to mean the surface material of a wall or building which is applied as a
plastic mass made by mixing certain materials with water letting the mass set by drying
carbonation or hydration The active or setting components of plaster are commonly clay
which sets by drying lime which sets by carbonation gypsum and pozzolana which sets by
hydration (Mini 2010)
There are different mixtures for rough plaster In all the mixtures clay limestone
lime and shells in powdered form serve as the matrix The particles of which are held
together by the organic materials like gum glue extracts from barks etc are in fact
adhesives The fine plaster layer requires more careful preparation because it is the layer on
which the pigments are laid to make the picture ldquoShilparatnardquo suggest a mixture of conch
Oyster shells or white clay with gum of neem or slaked lime and coconut water Here the
consolidation is effected by the carbonation of slaked lime ie it absorbs carbon dioxide
from air and becomes carbonate Mural paintings were lime-washed from the 17th until the
beginning of 19th century A few paintings in vaults were never lime-washed for example
at Taby and Floda painted by the medieval painter Albertus Pictor (Mini 2010)
All the paintings have certain basic common characteristics There has to be a wall
or rock surface called support over which the artist goes to work A plaster base called
ground of varied thickness is laid on the support The ground may consist of one or more
layers The strength and life of the whole mural depended up on this ground over which the
painting was done It is the process of applying the final painting on the ground determines
the character of the mural whether it is fresco or tempera The mural painting is done
usually by creating wall surface free of any previous oil or paint by using solvent or by
sand blasting The brick wall is first plastered with mixture of lime and sand in the ratio of
12 A mixture of egg yolk vinegar oil colour is used in dry plaster
There are at least six stages before a Kerala Mural Painting is complete Lekhya
Karma is the first stage where sketching by pencil or crayon is done The second stage is
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
20 Review of Literature
the Rekha Karma which enhances the outlines of the sketching done The third stage called
Varna Karma breathes life into the painting with its colours Here all colours are
appropriately filled in The colouring of the human figures is done according to the
characters and their common virtues The divine and noble characters (Saatvik) are painted
in green those inclined towards power and wealth (Raajasik) is painted in shades of red
lowly mean characters (Tamasik) in white and demons in black In the fourth stage or the
Vartana Karma shading is done Fifth stage called the Lekha Karma brings us to the final
outline of the painting which is usually in black The final and the finishing touches stage
are called Devika Karma (Warrier 2011)
29 Dyes used in mural painting
Indians have been considered as fore runners in the art of natural dyeing Natural
dyes find use in the colouring of textiles drugs cosmetics etc Owing to their non-toxic
effects they are also used for colouring various food products In India there are more
than 450 plants that can yield dyes In addition to their dye-yielding characteristics some
of these plants also possess medicinal value Though there is a large plant resource base
little has been exploited so far Due to lack of availability of precise technical knowledge
on the extracting and dyeing technique it has not commercially succeeded like the
synthetic dyes (Siva 2007)
The color materials on the mural paintings in ancient India were derived from the
natural materials like terracotta chalk red ochre and yellow ochre mixed with animal fat
The dyes for painting is prepared such as white from lime Black from carbon soot of
lamps Red and yellow from minerals Blue from indigo ferra Deep red from lac A fine
coating of resin is done after the painting in order to make a shining appearance Egg yolk
and vinegar was mixed with oil colors and painted on dry plaster (Krishnakumar 1999)
Although plants exhibit a wide range of colours not all of these pigments can be
used as dyes Some do not dissolve in water some cannot be adsorbed onto fibres whereas
others fade when washed or exposed to air or sunlight It remains a mystery why plants
reward us with vibrant dyes India has a rich biodiversity and it is not only one of the
worldrsquos twelve mega diversity countries but also one of the eight major centres of origin
and diversification of domesticated taxa It has approximately 490000 plant species of
which about 17500 are angiosperms more than 400 are domesticated crop species and
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
21 Review of Literature
almost an equal number their wild relatives Thus India harbours a wealth of useful
germplasm resources and there is no doubt that the plant kingdom is a treasure-house of
diverse natural products One such product from nature is the dye (Siva 2007)
Many natural dyestuff and stains were obtained mainly from plants and dominated
as sources of natural dyes producing different colours like red yellow blue black brown
and a combination of these Almost all parts of the plants like root bark leaf fruit wood
seed flower etc produce dyes It is interesting to note that over 2000 pigments are
synthesized by various parts of plants of which only about 150 have been commercially
exploited Nearly 450 taxa are known to yield dyes in India alone of which 50 are
considered to be the most important ten of these are from roots four from barks five from
leaves seven from flowers seven from fruits three from seeds eight from wood and three
from gums and resins Some important dye-yielding plant habitats their distribution and
colouring pigment (Siva 2007)
The dye is generally prepared by boiling the crushed powder with water but
sometimes it is left to steep in cold water The solution then obtained is used generally to
dye coarse cotton fabrics Alum is generally used as a mordant Flowers of Butea
monosperma (Lam) Taubert yield an orange-coloured dye which is not fast and is easily
washed away For the purpose of colouring the material is steeped in a hot or cold
decoction of the flowers A more permanent colour is produced either by first preparing the
cloth with alum and wood ash or by adding these substances to the dye-bath The dye
indigo is produced by steeping the plant in water and allowing it to ferment This is
followed by oxidation of the solution with air in a separate vessel Mallotus philippinensis
muell yields an orange colour used for dyeing silk and wool To prepare the annatto dye
from B orellena the fruits are collected when nearly ripe The seeds and pulp are removed
from the mature fruit and macerated with water Thereafter they are either ground up into
an lsquoannatto pastersquo or dried and marketed as annatto seeds Sometimes when the seeds and
pulp are macerated with water the product is stained through a sieve and the colouring
matter which settles out is collected and partially evaporated by heat and finally dried in
the sun (Sowbhagya 2002)
The predominant colors used in rock art and cave art are black (from charcoal soot
or manganese oxide) yellow ochre (limonite) red ochre (hematite or baked limonite) and
white (kaolin clay burnt shells powdered gypsum or powdered calcium carbonate) All of
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
22 Review of Literature
theses pigments may be used on leather or raw hide as well Early cave art in Seminole
Canyon was monochromatic in red and as culture grew more sophisticated the color
palette expanded Blue Orange Brown Green and Purple are the most common colours
used in Ajantha murals White Pink Gold are occasionally represented mineral earths
containing ferric oxide and copper carbonates were used as source of red yellow and green
colours There is also evidence to establish that root of Rubia cardifolia and leaves of
Indigofera tinctoria were used as source for red and blue colours (Nayer et al 1999)
Many colors of pigments were obtained from both organic and inorganic sources in
ancient times and used to paint various surfaces such as braintan leather clothing and
accoutrements rawhide the human body etc Blue color was obtained from powdered
azurite and lapis duck manure and certain clays Fine Blue-green clay was obtained from
deposits near Mankato Michigan Organic sources of blue include Turkeys Tail a
greenish blue polypore that grows on dead decaying wood (not tannish ones) Native
Americans get Indigo from either Guatemala or Ecuador which was traded well up onto
Kansas long before the Spanish ever set foot here American Indigo has purple tones to it
but IndianJapanese indigo has green tones Berries and crushed flowers were also used to
obtain blue color by rubbing the plant material directly on the leather
An organic source of red was Cochineal It was native west of the Mississippi and
is produced from the bodies of small insects that grow on the prickly pear cactus Ladys
Bedstraw gives a good vermillion red color Harvest the roots dry them out clean the mud
etc off of them and then grind the roots really fine then soak them to extract the red
coloring The key here is drying the root first Blood was also used as red pigment Pucoon
roots also yield a red pigment (Smith 2002) Red ochre the reverse original red colours are
due to variations in iron oxide (or) calcite content and to redox conditions in the firing
produced Brown coloured ceramics owe their colour to maghemite and must be
considered as a fabrication defect due to the position of the ceramic piece in a zone where a
reducing atmosphere prevailed in the course of firingRed pigments were produced from
iron oxides like hematite or limonite and from ochre Hematite was the most frequently
used mineral It occurs in the form of aggregates of small red crystals or in the form of
bigger black crystals which are difficult to crush white was obtained mostly from
kaolinite or illite (Clottes et al 1990)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
23 Review of Literature
210 Biodetoriation of mural paintings
Historic items often contain natural biodegradable materials and have histories of
exposure to moist conditions These two conditions make them amenable to microbial
attack Microbial colonization may damage the building or the cultural asset
(Salonen 2001) Biodeteriogens are organisms involved in deterioration of artifacts They
are very specific for each type of artifact in accordance with its chemical structure and
environment They also have different nutritional requirements and act directly or
indirectly on the substrate The adhesion of microorganisms to a substrate is the result of
cell hydrophobicity and of excreted polymeric substances contained by sheaths capsules
and slimes (Colao 2005)
The surviving wall paintings and decorations in subterranean environments around
Malta are rather scarce (Buhagiar 1986 1993 1998) These include those at St Paulrsquos
Catacombs (Zammit 2008) St Agatharsquos Crypt and Catacombs (Camilleri 2001)
San Catald Catacombs Tac-Cghaqi Abbatija tad-Dejr (Buhagiar 1993) all in Rabat the
cave-sanctuary in Mellieħa (Buhagiar 1987) and the Ħal Saflieni Hypogeum in Paola
(Pace 2000) Previous studies conducted on wall paintings and decorations in Maltese
Palaeo-Christian Catacombs have involved their manufacturing techniques (Muscat 2005)
However to date limited systematic studies have been conducted into the biodeterioration
in Maltese Palaeo- Christian Catacombs The only such studies ever conducted in Malta
concerned the biodeterioration of works of art in catacombs have been carried out at St
Agatharsquos Crypt and Catacombs in Rabat (Zammit et al 2008 Psaila 2006)
Microorganisms can be responsible for the destruction of monuments buildings
and cultural heritage assets including the decay of concrete cement stones mural
paintings etc These microorganisms are not only related with biodeterioration but water-
damaged indoor building materials are frequently colonized by complex bacterial
communities and may emit mixed bioaerosols into the indoor air (Jimenez 2000) It is
well known that mural paintings are colonized by micro-organisms and can be severely
damaged by such growths (Ciferri 1999) A large number of fungal (gt50) and bacterial
taxa (70) have been detected in indoor environments Over 50 bacterial species and 14
genera novel to science were reported in the past 10 years from indoor air and historic
items indicating bacterigravea in these enviroments are as yet only fragmentarily known
(Salonen 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
24 Review of Literature
Traditionally the study of microflora which causes this biodeterioration was based
on classical cultivation methods that were mainly useful to study the physiological
potential of microorganisms but do not provide information on all microbial communities
to be found in excavated artifacts Indeed many studies using culture-independent
techniques which cultivate microorganisms from different environments may often
represent only minor components of the microbial community as a whole It is generally
accepted that cultivation methods recover less than 1 of the total microorganisms present
in environmental samples (Ward et al 1990 Amann et al 1995) Hence microbial
investigations based only on cultivation strategies cannot be regarded as reliable in terms
of reflecting the microbial diversity present in objects of art (Osburn et al 2011)
Early workers suggested that the presence of living microorganisms on stone
increased its susceptibility to damage through their water-binding capacity It has recently
been reported that the mineralogy porosity surface roughness and capacity to collect
water and organic materials control its bioreceptivity and tendency to biodeterioration
(Diakumaku 1995) In addition environmental factors as temperature light pH and
relative humidity affect the number and type of colonising species (Tiano et al 1995) and
hence the progress of colonisation Biofilms on decayed stones consist on mixed microbial
populations embedded in a polymeric matrix Fungi algae filamentous and unicellular
bacteria are found in these complex communities A variety of bacteria have been isolated
from different stone samples confirming the dominance of Gram-positive organisms
especially spore-forming bacteria such as Bacillus and filamentous actinomycetes
(Ripka 2005)
In cultivation studies of deteriorated mural and rock paintings bacterial isolates
have frequently been attributed to the genus Bacillus (Weirich 1989 Tate and Rebrikova
1991 Gonzalez et al 1999 Heyrman et al 1999 Jimenez et al 2000) Other studies that
have included DNA-based techniques to characterize the bacterial community involved in
biodeterioration have shown that a substantial part of the bacterial population is made up of
so far unknown species (Altenburger et al 1996 Rolleke et al 1996 Gurtner et al 2000
Heyrman and Swings 2001) (Heymann et al 2003)
Many potential mycotoxin producers have been detected in air and items from
indoor environments with histories of exposure to moisture for example species of
Acremonium Alternaria Aspergillus Chateomium Fusarium Eurotium Paecilomyces
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
25 Review of Literature
Penicillium Scopulariopsis Stachybotrys Trichoderma Verticillium and Wallemia
(Peltola et al 2001 Pieckova et al 2001) Not all strains of one species produce
mycotoxins and different strains may produce different toxins Whereas toxin producing
strains are frequent in crops and outdoor vegetation toxin producing isolates from indoor
environments and non living assets have only been reported of the species Aspergillus
versicolor (Nielsen et al 1998) Stachybotrys chartarum Nikulin (1997) and
Trichoderma harzianum (Peltola et al 2001) Streptomyces griseus strains producing
valinomycin occur in environments where humans can get exposed
(Andersson et al 2002) The biological properties and toxicity mechanisms of cereulide
were identical to those by valinomycin (Mikkola et al 1999 Salonen et al 2001)
The genus Paenibacillus was first proposed by Ash et al (1993) and its description
was emended by Shida et al (1997) The genus Paenibacillus is under intensive taxonomic
investigation with ten species having been formally described in the last year Heyrman amp
Swings (2001) isolated a strain originally classified as Paenibacillus sp LMG 19508
from biodeteriorated mural paintings in the Servilia tomb at the Roman necropolis of
Carmona in Seville Spain (Smerda et al 2006) Building stone and wall paintings contain
a variety of hydroscopic salts including carbonates chlorides nitrates sulfates etc
dispersed within the porous material or locally concentrated These salts are solubilised
and migrate with the water in and out of the stone Due to changes in physical parameters
the so called salt efflorescences appear on the surfaces providing extremely saline
environments and building niches for settlement of halophilic microorganisms Halite and
other hygroscopic salts can retain considerable quantities of moisture when entrapped in
the building materials and thus favouring the bacterial growth (Ripka 2005)
It is demonstrated that water-damaged indoor building materials contained
substances of microbial origin extremely toxic to eukaryotic cells and large quantities of
several microbial species known to be potentially toxic or immunopotentiating These
include peptidoglycans Gram-negative endotoxin β-13-D glucans lipoglycans and
teichoic acids and mycotoxins (Jimenez 2000) In turn these microorganisms can mediate
the crystallization process These crystallizations can produce destructive effects Some
salts may crystallize or recrystallize to different hydrates which occupy a larger space and
exert additional pressure producing cracking powdering and flaking
(Jimenez and Laiz 2000)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
26 Review of Literature
211 Types of deterioration on mural paintings
The frescos represent a variety of ecological niches where primary colonization is
due to photoautotrophic and chemolithoautotrophic microorganisms followed by
secondary colonization due to heterotrophic bacteria that obtain nutrients from various
sources (metabolites of autotrophic bacteria airborne organic contamination animal faeces
and organic compounds in the paint layers themselves) Microbial-induced deterioration
processes cause structural as well as aesthetic damage to wall paintings such as the
discoloration of materials the formation of crusts on surfaces and the loss of material
(Sarro et al 2006 Osburn et al 2011) Halophilic bacteria and archaea were thought to
be found only in extreme environments like salt lakes or black smokers However it has
been shown that mural paintings and stones are a common habitat for extremely salt
tolerant and moderate halophilic (Ripka 2005) Microbial induced deterioration processes
can cause different kinds of alterations such as discolouration of materials the formation of
crusts on surfaces and the loss of material which leads to structural damage (Ripka 2005)
First of all microorganisms can cause severe problems due to the excretion of aggressive
metabolic products such as organic or inorganic acids Secondly material components can
be used as substrates for microbial metabolism Exoenzymes such as cellulases proteases
tannases beta-glucosidase produced by fungi and bacteria are responsible for hydrolysis of
cellulose and proteins Further examples are mechanical processes caused by swelling and
shrinking of slime or mycelia penetrating inside plaster of the painting resulting in loss of
cohesion and detachment of the paint layer (Rolleke 1996 Gurtner et al 2000)
Table-21 Microbial damage on mural paintings (Rolleke 1996)
S No Damage Microbial activity
1 Green brown red grey
surface layers (patinas)
Pigments produced by microorganisms (intra-or
extracellular) as chlorophyll and carotinoids
2 Dislodging of painting layers Use of organic binders as nutrient and energy
source
3 Acid attack of carbonates Acid produced by fungi or bacteria
4 Discolouration of pigments Redox-reactions induced by fungi and
bacteria
5 Loss of paint layer Growth of microorganisms deep into the plaster
6 Hydrolysis of synthetic
polymers Chemoorganotrophic activity of bacteria and fungi
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
27 Review of Literature
Discolorations are caused by excretion of pigments and microbiologically induced
reductionoxidation-processes (Krumbein et al 1990) Degradation of the bindings is
followed by reduction of stability Oxidation of ammonium and reduced sulphur
compounds results in acidification of the environment such as Sulphuric acid and the
variety of organic acids produced by the heterotrophs cause solubilization of calcareous
binding material and chelation of metal ions (Bock et al 1993) It is now well recognised
that wall paintings can be deteriorated by microorganisms (Ciferri 1999)The growth of
microorganisms essentially results in two types of damage aesthetic and structural
Aesthetic damage implies pigment discoloration stains and formation of a biofilm on the
painted surface Structural damage is observed as cracking and disintegration of the paint
layer formation of paint blisters and degradation of support polymers or of glues and
binders resulting in detachment of paint layer from the support The colonization of mural
paintings by bacteria and other microorganisms can have different causes Provided that
favorable environmental conditions occur nutrients for heterotrophic bacteria and fungi
can be available from metabolites of autotrophic bacteria from airborne contamination and
dripping water from animal faeces but also from organic compounds in the paint layer
itself
212 Methods of studying biodeterioration
It is now well recognized that wall paintings may be deteriorated by
microorganisms as established by several studies that linked the observed damage with the
microbial community present as reviewed by Ciferri (1999) Despite this knowledge a
reliable characterization of bacteria associated with such damage is often lacking To
obtain greater insight into the bacterial community involved in biodeterioration of mural
paintings three sites (from the necropolis at Carmona Spain and the Saint-Catherine
chapel of the castle at Herberstein Austria) were sampled In previous studies from these
sites 385 isolates were analysed by fatty acid methyl ester GC and representatives of
different fatty acid clusters were further studied by 16S rRNA gene sequencing
(Heyrman and Swings 2001) Several of these representative strains showed the highest
sequence similarity with members of the genus Arthrobacter (Heyrman et al 2005)
Jimenez and Samson (1981) analysed the microbial flora of a large fresco painted
in the late 1920s in the monastery ldquoSanta Maria de la Rabidardquo (Huelva Spain) exhibiting
two types of deterioration white efflorescence and green-to-black stains
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
28 Review of Literature
Tate and Rebrikova (1990) thought autotrophic nitrifying bacteria to be the first colonisers
of damaged frescoes and building materials in the cathedral of the nativity of the Virgin in
the Pafnutii-Borovskii monastery (Russia) The bulk of research on biodeterioration of
mural paintings has focused on explaining the observed phenomena by analysing the
microflora present Following this approach a precise characterisation of the
microorganisms using a polyphasic approach was never the first goal
Only a few studies included genomic fingerprinting (16S rDNA sequence analysis)
for the characterisation of bacteria associated with damage on mural paintings
[Rolleke (1996) Pinar et al (2001)] Previous studies based on culture-dependent
techniques showed that the flora present on frescos are fungi (predominant species of
Penicillium Aspergillus Cladosporium and Engyodontium) (Guglielminetti et al 1994)
bacteria (predominant species of Bacillus Arthrobacter Micrococcus Streptomyces and
Pseudomonas) (Heyrman et al 1999) cyanobacteria and eukaryotic algae (species of
Nostoc Lyngbya and Chlorophyceae) (Arino et al 1996 Calvo et al 1993) The killing
effect of an antimicrobial agent on a microorganism can be assessed in several ways
(1) Lethal activity may be expressed as the rate of killing by a fixed concentration
of drug under controlled conditions This rate is determined by measuring the number of
viable bacteria at various time intervals The resulting graphic depiction is known as the
time-kill curve Bacterial killing rates are in part dependent on the class of antibiotic and
the concentration of this agent With certain classes of antibiotics (eg aminoglycosides
and fluoroquino-lones) the rate of killing increases with increased drug concentrations up
to a point of maximum effect This is termed concentration-dependent bactericidal activity
In contrast the killing rates of szlig-lactam agents and vancomycin are relatively slow and
continue only as long as the concentrations are in excess of the MIC This rate of killing is
termed time-dependent bactericidal activity
(2) The minimal concentration of drug needed to kill most of the viable organisms
after incubation for a fixed length of time (generally 24 hours) under a given set of
conditions is the most common estimation of bactericidal activity and is known as either
the minimal bactericidal concentration (MBC) or the minimal lethal concentration (MLC)
It will be referred to in this document as the MBC Unfortunately the definition of the
MBC (999 killing of the final inoculum) is somewhat arbitrary and separates the
bacteria into two populations ndash a segrega-tion which might not have biological relevance
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
29 Review of Literature
The determination of the MBC moreover is so subject to methodologic variables that the
clinical relevance of MBCs is nearly impossible to assess particularly for certain pathogen
and drug combinations (eg Staphylococci and beta-lactam agents)
(3) The serum of a patient receiving an antibiotic may be tested against the
infecting microorganism This can be done using time-kill curve methodology (ie serum
bactericidal rate) or using dilution methodology (ie serum bactericidal titer) The
principles of these methods as well as the influence of biological and technical factors are
similar (Barry et al 1999)
213 Microbial flora associated with deteriorated mural paintings
A great deal of research has been done in this field mainly by using cultivation dependent
methods However by using culture-dependent methods only a very small proportion of
microorganisms can be obtained Far less than 1 of organisms in the environment can be
cultivated by standard cultivation techniques (Pace 1996) Recent studies have shown that
culture-dependent techniques yielded mainly sporeforming bacteria suggesting that plating
leads to an over estimation of the number of spore-forming bacteria A wide number of
investigations have shown that in addition to chemical and physical processes
microorganisms play a major role in degradation of objects of art such as paintings stone-
works wood paper masonry leather parchment glass and metal (Ripka 2005)
A) Bacteria
In general growth of diverse organisms on mural paintings is supported by
humidity slight alkaline pH values and the presence of organic and inorganic nutrient
sources (Weirich 1989) In mural paintings pigments are suspended in water or oil often
binders such as casein and milk are used and they are supplied on the damp lime plaster
(Ciferri 1999) The calcium carbonate formed on contact with air consolidates the
pigments Thus frescos contain mainly inorganic components While chemoautotrophic
nitrifiers and thiobacilli obtain their energy for growth by oxidizing ammonium and
reducing sulphur-compounds respectively heterotrophic bacteria and fungi depend on
organically bound carbon [Tate et al (1991) Lazar (1971) Petushkova et al (1986)
Jimenez et al (1981)] Thus primary colonization of photoautotrophic Cyanobacteria
chemolithoautotrophic nitrifying bacteria and sulphuric acid producing thiobacilli represent
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
30 Review of Literature
the first supply of organic matter The death and lysis of such bacteria promotes the
secondary settlement of heterotrophic bacteria and fungal populations (Calvo et al 1991)
Bacteria may derive from plants or pollen as many sequences obtained in this study
gave high score similarities with bacteria isolated from plants like Moraxella osloensis
Enterobacter cloace Enterobacter agglomerans and Pantoea endophytica Bacteria may
also derive from animal faeces like flies Bacillus Pseudomonas Aeromonas and Panteoa
(Ripka 2005) As Lazar and Dumitru (1973) reported studying mural paintings in a
Romanian monastery the genera Bacillus Arthrobacter and Pseudomonas have been
proved to produce salt efflorescences and were even considered to cause the blanching
phenomenon of frescoes (Jimenez et al 2000) Predominant bacterial genera are Bacillus
Streptomyces Arthrobacter Micrococcus and Pseudomonas [Weirich (1989)
Tate et al (1990) Arroyo et al (1997) Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
B) Fungi
It may be concluded that there is wide variety of fungal forms present on mural
paintings but Aspergillus and Alternaria were found dominating from all the experimental
sites next to them were Cladosporium Drechestera Fusarium Curvularia Chaetomium
Memnoniella Mycelia sterelai Pencillium Emericella Stachybotrytis Trichoderma
Phoma Monodictys Humicola and Epicoccum (Garg et al 1995)
The fungal genera most commonly found in lists of isolated taxa given in literature
are Alternaria Aspergillus Chaetomium Cladosporium Fusarium Penicillium and
Verticullum [Weirich (1989) Tate et al (1990) Guglielminetti et al (1994)
Garg et al (1995) Berner et al (1997) Ciferri (1999)] Some fungi having hard fruiting
bodies represented by sclerotia pycnidia perithecia cleistothecia and stroma could
organize themselves inside the painted layer Many fungal forms having such structures
were identified from our experimental sites viz Emericella nidulans A flavus
Chaetomium sp and Phoma sp etc These structures with little increase in humidity may
cause swelling in the paint film (Garg 1995)
Strains of species of Alternaria and Cladosporium both of them identified on the
mural paintings of the Palace of Schoumlnbrunn are the most common genera isolated from
stone and mural paintings in indoor environments with standard cultivation methods
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
31 Review of Literature
(Ventosa 2004) Saprophytic species of the genus Cladosporium are among the most
abundant fungi isolated in saltern samples Commonly isolated Cyanobacteria belong to
Nostoc and eukaryotic algae to Lyngbya and members of the Chlorophyceae such as
Chlorella Pseudococcomyxa and Pseudopleurococcus [Gorbushina et al (1987)
Calvo et al (1993) Arino et al (1996)]
They grow optimally on media with low water activity due to high salt or sugar
concentrations seem to propagate 70 vegetatively in the salterns and are thus
halotolerantosmotolerant species rather than simple flush-through occurrences
Cladiosporum herbarum was frequently isolated from hypersaline waters dead and dying
plant material air soil food fruit cereals paint and textiles (Ventosa 2004)
C) Algae
Most of the painted areas in temperature climate became covered with green algae
(Pleurococcus Protococcus and Trentopholia) while under tropical conditions blue green
algae of the genera Oscillatoria and Sytonema predominated (Garg 1995) The main
factors which contribute to the growth of algae on wall paintings are the presence of
moisture in the plaster as well as availability of visible light These conditions are quite
prevalent in the tropical climate but in temperature regions also algal growth on wall
paintings have been reported [Tonolo et al (1961) Pietrini et al (1991)]
D) Actinomycetes
Usually literature refers to specific aspects eg the occurrence of cyanobacteria
and algae in caves with natural openings to sunlight or those with artificial lighting fungi
and so forth Actinomycetes have been considered to be mainly confined to soils where
they find their natural habitat but despite intensive studies there are still many gaps in our
knowledge of the role played by actinomycetes in soil processes and biodegrations of
murals cave paintings (Groth et al 1999) In addition halophilic bacteria actinomycetes
and cyanobacteria are also capable of growing on salt-affected mural paintings
(Karbowska 2003)
Monte and Ferrari (1993) reviewed the mechanisms of biodeterioration in tombs
and underground churches The role of actinomycetes in the deterioration of frescoes in
hypogean environments was stressed by Agarossi et al (1985) Monte and Ferrari (1993)
Giacobini et al (1987) described the serious damage suffered by a whole series of famous
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
32 Review of Literature
frescoes in underground environments Actinomycetes were isolated from these mural
paintings located in crypts caves and tombs About 200 strains of actinomycetes were
isolated 60 of which were identified The most frequent species were Streptomyces albus
S cinereoruber S griseolus S vinaceus and some members of the Nocardia genus
Heterotrophic bacteria and actinomycetes were the most abundant microorganisms
on the frescoes of Etruscan tombs (Agarossi et al 1985) Bettini et al (1977) studied
some of the oldest Etruscan tombs (7th to 4th century BC) and found white-grey patinas
and spots from streptomycetes in the mural paintings They related the biodeterioration to
the microclimatic conditions (eg lower temperatures high RH) Monte and Ferrari (1993)
considered that colonization of the mural paintings was the result of selective competitive
and inhibitory dynamics among different microorganisms under different and changing
environmental conditions The pigments excreted by some actinomycetes were responsible
for the violet stains found on the walls of tombs in Tarquinia Similar stains were observed
in one of the Roman tombs the Circular Mausoleum the Necropolis of Carmona Spain
from which a Streptomyces sp producing violet pigments in culture media was isolated
214 Identification of biodeteriogens
The possibility of pigments and biodeteriogens identification in frescos and stone
monitoring is offered mostly by vibrational spectroscopy infrared thermography laser
induced fluorescence (LIF) laser induced breakdown spectroscopy (LIBS) XRF (X-Ray
Fluorescence) IR and UV emission Among them laser based methods allowing for in
situ or remote characterization of artwork surface were applied successfully for
prospecting diagnosis and maintenance (Colao et al 2005) The rep-PCR fingerprinting
of the isolates allowed determination of their genotypic diversity Studies that have
compared rep-PCR genomic fingerprint analysis with DNAndashDNA relatedness studies have
shown that the two techniques yield results that are in close agreement [Nick et al (1999)
Rademaker et al (2000)] These studies therefore suggest that rep-PCR fingerprinting can
be used as a genomic screening method to differentiate at the species level and to select
representatives for DNAndashDNA reassociation experiments (Heymann et al 2003)
The characterisation of bacteria was for example often limited to isolation from
group-specific media followed by microscopy [Sorlini et al (1987) Weirich (1989)
Tate et al (1990) and in more recent studies to morphological and physiological
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
33 Review of Literature
characteristics including miniaturised and automated systems such as API and BIOLOG
[Arroyo et al (1997) Jimmenez et al (2000) and Laiz et al (2000)] or to
chemotaxonomic characteristics [Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
Wagner et al (1994) demonstrated that conventional microbiological efforts can
fail to isolate all microorganisms present in natural samples DNA-based techniques used
to identify microorganisms have revealed only a smaller fraction of bacteria isolated from
artworks (Ward et al 1990 Rolleke et al 1996) Bacterial identification using molecular
techniques especially those including the sequencing of genes coding for ribosomal
16S rRNA is very important to study bacterial communities found on artefacts One such
method is Denaturing Gradient Gel Electrophoresis (DGGE) of PCR-amplified gene
fragments coding for rRNA (Muyzer et al 1993) that allows the separation of partial
16S rDNA amplified fragments of identical length but different sequence due to their
different melting behaviour in a gel system containing a gradient of denaturants
(Jimenez 2003)
Total genomic DNA was purified for 16S rRNA gene sequencing and rep-PCR
using a slight modification of the method of Pitcher et al (1989) as described by
Heyndrickx et al (1996) rep-PCR genomic fingerprinting was performed with the REP-
and (GTG)5 primers (Versalovic et al 1994) using the PCR conditions described
previously by Rademaker et al (1997) Electrophoresis and pattern analysis were further
performed as described by Heyrman et al (2003) 16S rRNA gene sequencing and
phylogenetic analysis were performed as described by Heyrman and Swings (2001)
Phylogenetic trees were constructed using the BioNumerics software (Applied Maths) by
applying the neighbour-joining and maximum-parsimony methods on a multiple alignment
similarity matrix The stability of relationships was assessed by a bootstrap analysis of
1000 datasets For determination of the G+C content and levels of DNAndashDNA
hybridization approximately 1 g biomass was harvested from agar plates DNA was
purified by using a combination of the protocols of Marmur (1961) and
Pitcher et al (1989) as described by Logan et al (2000) The G+C content of the DNA
was determined by HPLC (Mesbah et al 1989) using the further specifications given by
Logan et al (2000) DNAndashDNA hybridization experiments were performed using a
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
34 Review of Literature
modification of the microplate method of Ezaki et al (1989) as described by
Willems et al (2001)
215 Preservation and conservation
Nowadays the conservation and preservation of our cultural heritage is one of the
world main concerns particularly in Europe The increasing need for non-destructive
investigation tools has become a major issue as sampling is in most cases restricted in
view of the value or the uniqueness of the object Artworks as wall paintings in buildings
and monuments of historical interest are affected by environment physical (temperature
and humidity) and biological factors (biodeteriogens) and by human (pollutant releases)
impact and therefore modified over the time The term ldquoconservationrdquo may have many
different meanings in different fields Every intervention directed to the restoration and
safeguard of works of art is commonly considered as a conservation treatment For
example conservation can involve the cleaning procedures set up by chemists or the photo
documentation of the preservation of historical memory For the appropriate conservation
of works of art even the lighting systems in a museum or the control of the visitorrsquos
movements in a site should be monitored Chemical degradation which induces the flaking
of paintings and deterioration from rain wind dust and other environmental causes is
mainly responsible for the weakening of the porous structure and the surface layers of the
materials used in works of cultural heritage (Colao et al 2005)
216 Conservation history
Wall paintings are an integral part of monuments and sites and should be preserved
in situ Many of the problems affecting wall paintings are linked to the poor condition of
the building or structure its improper use lack of maintenance frequent repairs and
alterations Also frequent restorations unnecessary uncovering and use of inappropriate
methods and materials can result in irreparable damage Substandard and inadequate
practices and professional qualifications have led to unfortunate results It is for this reason
that an appropriate document covering the principles of proper conservation-restoration of
wall paintings is necessary
The Venice Charter (1964) has provided general principles for the conservation-
restoration of cultural heritage The Amsterdam Declaration (1975) introducing the
concept of integrated conservation and the Nara Document on Authenticity (1994) dealing
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
35 Review of Literature
with cultural diversity have expanded these principles Taking into account these and
additional relevant contributions such as the ICOM-CC Code of Ethics (1984) Document
of Pavia (1997) and ECCO Professional Guidelines (1997) the aim of this document is
to provide more specific principles for the protection preservation and the conservation
restoration of wall paintings This document therefore reflects basic and universally
applicable principles and practices and does not take into account particular problems of
regions or countries which can be supplemented at regional and national level by
providing further recommendations where necessary
217 Preservation techniques of the mural paintings
The removal of fat salts varnishes and pollutants from the surfaces of the works
of art are mostly done by chemical and mechanical methods At the end of the 19th
century the practices of restoration methods that do not inhibit further future interventions
was considered acceptable During the 1960s several chemicals such as polymeric resins
were synthesized and applied as a consolidation or protection agents The accepted idea
was that these substances could be removed at any time leaving a completely unaltered
substrate On the basis of origin archaeological objects can be classified as follows
(Carretti 2005)
1 Inorganic It includes siliceous and nonsiliceous materials Archaeological materials
produced from stones terracotta ceramics and glass can be included under siliceous
materials whereas objects made of metals can be included under nonsiliceous inorganic
materials Again metal objects can be classified as ferrous metals and non-ferrous metals
Objects made of iron are termed as ferrous metal objects whereas metal objects made from
other than iron is termed as non-ferrous metal objects
2 Organic It includes archival and anthropological materials Again archival materials
include paper bhojapatra tadapatra textiles wooden objects miniature paintings whereas
anthropological objects include bone and ivory leather feather and fur etc
In the past restoration of paintings and other old artwork often involved application
of acrylic resins to consolidate and protect them One of the most important tasks for
modern restorers is thus to remove these layers because it turns out that acrylic resins not
only by drastically changing the optics of the treated artwork but in many cases they
accelerate their degradation The scientists use an oil-in-water microemulsion with the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
36 Review of Literature
organic solvent para-xylene as the oil component The matrix makes the cleaning agent
viscous so that it cannot enter very far into the pores of a painting (Carretti 2005)
Nanoparticle treatment is the logical evolution of the Ferroni-Dini method
Dispersions of kinetically stable Ca (OH)2 nanoparticles in non-aqueous solvents solved
most of the drawbacks of the microsized powders Stable dispersions of calcium hydroxide
have been successfully applied (replacing polymers) as fixatives to re-adhere lifted paint
layers during many restoration workshops in Italy and in Europe as a consolidant The
FerronindashDini method (two steps the application of a saturated solution of ammonium
carbonate (NH4)2CO3 and the treatment with a barium hydroxide solution Ba(OH)2 also
called the barium method has long been the acknowledged method for the removal of
salts that threaten paintings reinforcing at the same time the porous structure However
commercially available carbonates and hydroxide powders have dimensions of several
micrometres much larger than the pores on the paint surface This means they donrsquot
penetrate the painting well and there is also a risk of damaging the artwork by a white
glaze forming on the surface (Berger 2006) Restoration should provide the reinforcement
of the porous structure and the consolidation of the surface layer of arte facts A few
simple principles can be considered to define the most appropriate restoration method
1) The treatment should be reversible so that one can revert to the original status of the
work of art at any desired time
2) All the applied chemicals must ensure the maximum durability and the chemical
inertness
3) The applied chemicals must invert the degradation processes without altering the
chemical composition of the artefacts and their physico-chemical and mechanical
properties (Baglioni 2006)
218 Commercial preservative used for preservation of mural paintings
Cleaning was done using soft brushes vacuum cleaner and Gumma paine (dough)
a natural latex sponge Areas near the window were very dirty with black soot and were
cleaned with micro fibrous cloths moistened with synperonic N (surfactant alkyl phenol
ethoxylate based on nonyl phenol) and neutralized with clean water In several places the
paint layers had separated from the substrate (exfoli-ation) In that cases loose paint flakes
were stuck back using Paraloid B72 (10 solution in ethanol) as sparingly as possible
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
37 Review of Literature
Paraloid was injected with syringe behind the exfoliated area twice pushed and held back
with Melinex (polyester film) until fixed on the third application (Bionda et al 2002)
In a period of significant growth of molds and intensive efforts to stop the mold
contamination some of the lines of certain paintings were obscured or faded Solutions of
ethanol formalin 91 and Thiabendazole (TBZ) were used but they were not very
effective Para-formaldehyde fumigation was adopted beginning in 1981 to establish an
emergency treatment sensitivity of microorganisms from studied samples was tested
against Desogen by adding 1-3 (v v) in serial dilutions The best concentration
3 (vv) was applied with a brush to prevent spreading of the spores In order to overcome
the problem of fungal attack suitable fungicides carbendizeme or kiroxy-I or 5 solute of
N formaldehyde can be used Shellac solution in spirit or 2 solution of polyvinaycletate
in toluene can be used as preservative and consolidantsTo control insect and fungal attack
fumigants like pyrethrum DDT or 5 solution of sodium penta chlorophenate in kerosene
oil 2 to 5 solution of PVA in toluene or 2 to 5 solution of paraloid B-72 in toluene or
acetone be used (Miura 2009) Microclimatic conditions constitute a critical factor in the
conservation of cave paintings The unstable microclimatic condition is one of the factors
that always affect the state of conservation of mural paintings In the environmental-
monument system knowledge of the functional environment and climatic conditions of the
surroundings are necessary for the identification of causes of decay (Singh 2011)
Furthermore the risk of formation of indoor bioaerosols in residential and public
buildings (offices schools museums etc) has attracted interest in the last years due to
socio-economic as well as sanitary reasons (Ripka 2005) Thus it is important in aspects of
health and maintenance of Cultural Heritage to analyse the complete microflora to further
develop biocides for harmful microorganisms and methods for restoration of damaged
objects of art The biocidal testing was carried out on one representative algal species of
the two classes of algae viz Chlorococcum sp (green) and Chroococcus sp (blue-green)
found to be common in all the samples Efficiency tests were carried out both in liquid as
well as solid media containing algal suspensions by adding a biocide solution of known
concentration and determining the growth of the microorganism after the incubation
period The biocides used for the past studies were
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
20 Review of Literature
the Rekha Karma which enhances the outlines of the sketching done The third stage called
Varna Karma breathes life into the painting with its colours Here all colours are
appropriately filled in The colouring of the human figures is done according to the
characters and their common virtues The divine and noble characters (Saatvik) are painted
in green those inclined towards power and wealth (Raajasik) is painted in shades of red
lowly mean characters (Tamasik) in white and demons in black In the fourth stage or the
Vartana Karma shading is done Fifth stage called the Lekha Karma brings us to the final
outline of the painting which is usually in black The final and the finishing touches stage
are called Devika Karma (Warrier 2011)
29 Dyes used in mural painting
Indians have been considered as fore runners in the art of natural dyeing Natural
dyes find use in the colouring of textiles drugs cosmetics etc Owing to their non-toxic
effects they are also used for colouring various food products In India there are more
than 450 plants that can yield dyes In addition to their dye-yielding characteristics some
of these plants also possess medicinal value Though there is a large plant resource base
little has been exploited so far Due to lack of availability of precise technical knowledge
on the extracting and dyeing technique it has not commercially succeeded like the
synthetic dyes (Siva 2007)
The color materials on the mural paintings in ancient India were derived from the
natural materials like terracotta chalk red ochre and yellow ochre mixed with animal fat
The dyes for painting is prepared such as white from lime Black from carbon soot of
lamps Red and yellow from minerals Blue from indigo ferra Deep red from lac A fine
coating of resin is done after the painting in order to make a shining appearance Egg yolk
and vinegar was mixed with oil colors and painted on dry plaster (Krishnakumar 1999)
Although plants exhibit a wide range of colours not all of these pigments can be
used as dyes Some do not dissolve in water some cannot be adsorbed onto fibres whereas
others fade when washed or exposed to air or sunlight It remains a mystery why plants
reward us with vibrant dyes India has a rich biodiversity and it is not only one of the
worldrsquos twelve mega diversity countries but also one of the eight major centres of origin
and diversification of domesticated taxa It has approximately 490000 plant species of
which about 17500 are angiosperms more than 400 are domesticated crop species and
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
21 Review of Literature
almost an equal number their wild relatives Thus India harbours a wealth of useful
germplasm resources and there is no doubt that the plant kingdom is a treasure-house of
diverse natural products One such product from nature is the dye (Siva 2007)
Many natural dyestuff and stains were obtained mainly from plants and dominated
as sources of natural dyes producing different colours like red yellow blue black brown
and a combination of these Almost all parts of the plants like root bark leaf fruit wood
seed flower etc produce dyes It is interesting to note that over 2000 pigments are
synthesized by various parts of plants of which only about 150 have been commercially
exploited Nearly 450 taxa are known to yield dyes in India alone of which 50 are
considered to be the most important ten of these are from roots four from barks five from
leaves seven from flowers seven from fruits three from seeds eight from wood and three
from gums and resins Some important dye-yielding plant habitats their distribution and
colouring pigment (Siva 2007)
The dye is generally prepared by boiling the crushed powder with water but
sometimes it is left to steep in cold water The solution then obtained is used generally to
dye coarse cotton fabrics Alum is generally used as a mordant Flowers of Butea
monosperma (Lam) Taubert yield an orange-coloured dye which is not fast and is easily
washed away For the purpose of colouring the material is steeped in a hot or cold
decoction of the flowers A more permanent colour is produced either by first preparing the
cloth with alum and wood ash or by adding these substances to the dye-bath The dye
indigo is produced by steeping the plant in water and allowing it to ferment This is
followed by oxidation of the solution with air in a separate vessel Mallotus philippinensis
muell yields an orange colour used for dyeing silk and wool To prepare the annatto dye
from B orellena the fruits are collected when nearly ripe The seeds and pulp are removed
from the mature fruit and macerated with water Thereafter they are either ground up into
an lsquoannatto pastersquo or dried and marketed as annatto seeds Sometimes when the seeds and
pulp are macerated with water the product is stained through a sieve and the colouring
matter which settles out is collected and partially evaporated by heat and finally dried in
the sun (Sowbhagya 2002)
The predominant colors used in rock art and cave art are black (from charcoal soot
or manganese oxide) yellow ochre (limonite) red ochre (hematite or baked limonite) and
white (kaolin clay burnt shells powdered gypsum or powdered calcium carbonate) All of
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
22 Review of Literature
theses pigments may be used on leather or raw hide as well Early cave art in Seminole
Canyon was monochromatic in red and as culture grew more sophisticated the color
palette expanded Blue Orange Brown Green and Purple are the most common colours
used in Ajantha murals White Pink Gold are occasionally represented mineral earths
containing ferric oxide and copper carbonates were used as source of red yellow and green
colours There is also evidence to establish that root of Rubia cardifolia and leaves of
Indigofera tinctoria were used as source for red and blue colours (Nayer et al 1999)
Many colors of pigments were obtained from both organic and inorganic sources in
ancient times and used to paint various surfaces such as braintan leather clothing and
accoutrements rawhide the human body etc Blue color was obtained from powdered
azurite and lapis duck manure and certain clays Fine Blue-green clay was obtained from
deposits near Mankato Michigan Organic sources of blue include Turkeys Tail a
greenish blue polypore that grows on dead decaying wood (not tannish ones) Native
Americans get Indigo from either Guatemala or Ecuador which was traded well up onto
Kansas long before the Spanish ever set foot here American Indigo has purple tones to it
but IndianJapanese indigo has green tones Berries and crushed flowers were also used to
obtain blue color by rubbing the plant material directly on the leather
An organic source of red was Cochineal It was native west of the Mississippi and
is produced from the bodies of small insects that grow on the prickly pear cactus Ladys
Bedstraw gives a good vermillion red color Harvest the roots dry them out clean the mud
etc off of them and then grind the roots really fine then soak them to extract the red
coloring The key here is drying the root first Blood was also used as red pigment Pucoon
roots also yield a red pigment (Smith 2002) Red ochre the reverse original red colours are
due to variations in iron oxide (or) calcite content and to redox conditions in the firing
produced Brown coloured ceramics owe their colour to maghemite and must be
considered as a fabrication defect due to the position of the ceramic piece in a zone where a
reducing atmosphere prevailed in the course of firingRed pigments were produced from
iron oxides like hematite or limonite and from ochre Hematite was the most frequently
used mineral It occurs in the form of aggregates of small red crystals or in the form of
bigger black crystals which are difficult to crush white was obtained mostly from
kaolinite or illite (Clottes et al 1990)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
23 Review of Literature
210 Biodetoriation of mural paintings
Historic items often contain natural biodegradable materials and have histories of
exposure to moist conditions These two conditions make them amenable to microbial
attack Microbial colonization may damage the building or the cultural asset
(Salonen 2001) Biodeteriogens are organisms involved in deterioration of artifacts They
are very specific for each type of artifact in accordance with its chemical structure and
environment They also have different nutritional requirements and act directly or
indirectly on the substrate The adhesion of microorganisms to a substrate is the result of
cell hydrophobicity and of excreted polymeric substances contained by sheaths capsules
and slimes (Colao 2005)
The surviving wall paintings and decorations in subterranean environments around
Malta are rather scarce (Buhagiar 1986 1993 1998) These include those at St Paulrsquos
Catacombs (Zammit 2008) St Agatharsquos Crypt and Catacombs (Camilleri 2001)
San Catald Catacombs Tac-Cghaqi Abbatija tad-Dejr (Buhagiar 1993) all in Rabat the
cave-sanctuary in Mellieħa (Buhagiar 1987) and the Ħal Saflieni Hypogeum in Paola
(Pace 2000) Previous studies conducted on wall paintings and decorations in Maltese
Palaeo-Christian Catacombs have involved their manufacturing techniques (Muscat 2005)
However to date limited systematic studies have been conducted into the biodeterioration
in Maltese Palaeo- Christian Catacombs The only such studies ever conducted in Malta
concerned the biodeterioration of works of art in catacombs have been carried out at St
Agatharsquos Crypt and Catacombs in Rabat (Zammit et al 2008 Psaila 2006)
Microorganisms can be responsible for the destruction of monuments buildings
and cultural heritage assets including the decay of concrete cement stones mural
paintings etc These microorganisms are not only related with biodeterioration but water-
damaged indoor building materials are frequently colonized by complex bacterial
communities and may emit mixed bioaerosols into the indoor air (Jimenez 2000) It is
well known that mural paintings are colonized by micro-organisms and can be severely
damaged by such growths (Ciferri 1999) A large number of fungal (gt50) and bacterial
taxa (70) have been detected in indoor environments Over 50 bacterial species and 14
genera novel to science were reported in the past 10 years from indoor air and historic
items indicating bacterigravea in these enviroments are as yet only fragmentarily known
(Salonen 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
24 Review of Literature
Traditionally the study of microflora which causes this biodeterioration was based
on classical cultivation methods that were mainly useful to study the physiological
potential of microorganisms but do not provide information on all microbial communities
to be found in excavated artifacts Indeed many studies using culture-independent
techniques which cultivate microorganisms from different environments may often
represent only minor components of the microbial community as a whole It is generally
accepted that cultivation methods recover less than 1 of the total microorganisms present
in environmental samples (Ward et al 1990 Amann et al 1995) Hence microbial
investigations based only on cultivation strategies cannot be regarded as reliable in terms
of reflecting the microbial diversity present in objects of art (Osburn et al 2011)
Early workers suggested that the presence of living microorganisms on stone
increased its susceptibility to damage through their water-binding capacity It has recently
been reported that the mineralogy porosity surface roughness and capacity to collect
water and organic materials control its bioreceptivity and tendency to biodeterioration
(Diakumaku 1995) In addition environmental factors as temperature light pH and
relative humidity affect the number and type of colonising species (Tiano et al 1995) and
hence the progress of colonisation Biofilms on decayed stones consist on mixed microbial
populations embedded in a polymeric matrix Fungi algae filamentous and unicellular
bacteria are found in these complex communities A variety of bacteria have been isolated
from different stone samples confirming the dominance of Gram-positive organisms
especially spore-forming bacteria such as Bacillus and filamentous actinomycetes
(Ripka 2005)
In cultivation studies of deteriorated mural and rock paintings bacterial isolates
have frequently been attributed to the genus Bacillus (Weirich 1989 Tate and Rebrikova
1991 Gonzalez et al 1999 Heyrman et al 1999 Jimenez et al 2000) Other studies that
have included DNA-based techniques to characterize the bacterial community involved in
biodeterioration have shown that a substantial part of the bacterial population is made up of
so far unknown species (Altenburger et al 1996 Rolleke et al 1996 Gurtner et al 2000
Heyrman and Swings 2001) (Heymann et al 2003)
Many potential mycotoxin producers have been detected in air and items from
indoor environments with histories of exposure to moisture for example species of
Acremonium Alternaria Aspergillus Chateomium Fusarium Eurotium Paecilomyces
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
25 Review of Literature
Penicillium Scopulariopsis Stachybotrys Trichoderma Verticillium and Wallemia
(Peltola et al 2001 Pieckova et al 2001) Not all strains of one species produce
mycotoxins and different strains may produce different toxins Whereas toxin producing
strains are frequent in crops and outdoor vegetation toxin producing isolates from indoor
environments and non living assets have only been reported of the species Aspergillus
versicolor (Nielsen et al 1998) Stachybotrys chartarum Nikulin (1997) and
Trichoderma harzianum (Peltola et al 2001) Streptomyces griseus strains producing
valinomycin occur in environments where humans can get exposed
(Andersson et al 2002) The biological properties and toxicity mechanisms of cereulide
were identical to those by valinomycin (Mikkola et al 1999 Salonen et al 2001)
The genus Paenibacillus was first proposed by Ash et al (1993) and its description
was emended by Shida et al (1997) The genus Paenibacillus is under intensive taxonomic
investigation with ten species having been formally described in the last year Heyrman amp
Swings (2001) isolated a strain originally classified as Paenibacillus sp LMG 19508
from biodeteriorated mural paintings in the Servilia tomb at the Roman necropolis of
Carmona in Seville Spain (Smerda et al 2006) Building stone and wall paintings contain
a variety of hydroscopic salts including carbonates chlorides nitrates sulfates etc
dispersed within the porous material or locally concentrated These salts are solubilised
and migrate with the water in and out of the stone Due to changes in physical parameters
the so called salt efflorescences appear on the surfaces providing extremely saline
environments and building niches for settlement of halophilic microorganisms Halite and
other hygroscopic salts can retain considerable quantities of moisture when entrapped in
the building materials and thus favouring the bacterial growth (Ripka 2005)
It is demonstrated that water-damaged indoor building materials contained
substances of microbial origin extremely toxic to eukaryotic cells and large quantities of
several microbial species known to be potentially toxic or immunopotentiating These
include peptidoglycans Gram-negative endotoxin β-13-D glucans lipoglycans and
teichoic acids and mycotoxins (Jimenez 2000) In turn these microorganisms can mediate
the crystallization process These crystallizations can produce destructive effects Some
salts may crystallize or recrystallize to different hydrates which occupy a larger space and
exert additional pressure producing cracking powdering and flaking
(Jimenez and Laiz 2000)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
26 Review of Literature
211 Types of deterioration on mural paintings
The frescos represent a variety of ecological niches where primary colonization is
due to photoautotrophic and chemolithoautotrophic microorganisms followed by
secondary colonization due to heterotrophic bacteria that obtain nutrients from various
sources (metabolites of autotrophic bacteria airborne organic contamination animal faeces
and organic compounds in the paint layers themselves) Microbial-induced deterioration
processes cause structural as well as aesthetic damage to wall paintings such as the
discoloration of materials the formation of crusts on surfaces and the loss of material
(Sarro et al 2006 Osburn et al 2011) Halophilic bacteria and archaea were thought to
be found only in extreme environments like salt lakes or black smokers However it has
been shown that mural paintings and stones are a common habitat for extremely salt
tolerant and moderate halophilic (Ripka 2005) Microbial induced deterioration processes
can cause different kinds of alterations such as discolouration of materials the formation of
crusts on surfaces and the loss of material which leads to structural damage (Ripka 2005)
First of all microorganisms can cause severe problems due to the excretion of aggressive
metabolic products such as organic or inorganic acids Secondly material components can
be used as substrates for microbial metabolism Exoenzymes such as cellulases proteases
tannases beta-glucosidase produced by fungi and bacteria are responsible for hydrolysis of
cellulose and proteins Further examples are mechanical processes caused by swelling and
shrinking of slime or mycelia penetrating inside plaster of the painting resulting in loss of
cohesion and detachment of the paint layer (Rolleke 1996 Gurtner et al 2000)
Table-21 Microbial damage on mural paintings (Rolleke 1996)
S No Damage Microbial activity
1 Green brown red grey
surface layers (patinas)
Pigments produced by microorganisms (intra-or
extracellular) as chlorophyll and carotinoids
2 Dislodging of painting layers Use of organic binders as nutrient and energy
source
3 Acid attack of carbonates Acid produced by fungi or bacteria
4 Discolouration of pigments Redox-reactions induced by fungi and
bacteria
5 Loss of paint layer Growth of microorganisms deep into the plaster
6 Hydrolysis of synthetic
polymers Chemoorganotrophic activity of bacteria and fungi
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
27 Review of Literature
Discolorations are caused by excretion of pigments and microbiologically induced
reductionoxidation-processes (Krumbein et al 1990) Degradation of the bindings is
followed by reduction of stability Oxidation of ammonium and reduced sulphur
compounds results in acidification of the environment such as Sulphuric acid and the
variety of organic acids produced by the heterotrophs cause solubilization of calcareous
binding material and chelation of metal ions (Bock et al 1993) It is now well recognised
that wall paintings can be deteriorated by microorganisms (Ciferri 1999)The growth of
microorganisms essentially results in two types of damage aesthetic and structural
Aesthetic damage implies pigment discoloration stains and formation of a biofilm on the
painted surface Structural damage is observed as cracking and disintegration of the paint
layer formation of paint blisters and degradation of support polymers or of glues and
binders resulting in detachment of paint layer from the support The colonization of mural
paintings by bacteria and other microorganisms can have different causes Provided that
favorable environmental conditions occur nutrients for heterotrophic bacteria and fungi
can be available from metabolites of autotrophic bacteria from airborne contamination and
dripping water from animal faeces but also from organic compounds in the paint layer
itself
212 Methods of studying biodeterioration
It is now well recognized that wall paintings may be deteriorated by
microorganisms as established by several studies that linked the observed damage with the
microbial community present as reviewed by Ciferri (1999) Despite this knowledge a
reliable characterization of bacteria associated with such damage is often lacking To
obtain greater insight into the bacterial community involved in biodeterioration of mural
paintings three sites (from the necropolis at Carmona Spain and the Saint-Catherine
chapel of the castle at Herberstein Austria) were sampled In previous studies from these
sites 385 isolates were analysed by fatty acid methyl ester GC and representatives of
different fatty acid clusters were further studied by 16S rRNA gene sequencing
(Heyrman and Swings 2001) Several of these representative strains showed the highest
sequence similarity with members of the genus Arthrobacter (Heyrman et al 2005)
Jimenez and Samson (1981) analysed the microbial flora of a large fresco painted
in the late 1920s in the monastery ldquoSanta Maria de la Rabidardquo (Huelva Spain) exhibiting
two types of deterioration white efflorescence and green-to-black stains
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
28 Review of Literature
Tate and Rebrikova (1990) thought autotrophic nitrifying bacteria to be the first colonisers
of damaged frescoes and building materials in the cathedral of the nativity of the Virgin in
the Pafnutii-Borovskii monastery (Russia) The bulk of research on biodeterioration of
mural paintings has focused on explaining the observed phenomena by analysing the
microflora present Following this approach a precise characterisation of the
microorganisms using a polyphasic approach was never the first goal
Only a few studies included genomic fingerprinting (16S rDNA sequence analysis)
for the characterisation of bacteria associated with damage on mural paintings
[Rolleke (1996) Pinar et al (2001)] Previous studies based on culture-dependent
techniques showed that the flora present on frescos are fungi (predominant species of
Penicillium Aspergillus Cladosporium and Engyodontium) (Guglielminetti et al 1994)
bacteria (predominant species of Bacillus Arthrobacter Micrococcus Streptomyces and
Pseudomonas) (Heyrman et al 1999) cyanobacteria and eukaryotic algae (species of
Nostoc Lyngbya and Chlorophyceae) (Arino et al 1996 Calvo et al 1993) The killing
effect of an antimicrobial agent on a microorganism can be assessed in several ways
(1) Lethal activity may be expressed as the rate of killing by a fixed concentration
of drug under controlled conditions This rate is determined by measuring the number of
viable bacteria at various time intervals The resulting graphic depiction is known as the
time-kill curve Bacterial killing rates are in part dependent on the class of antibiotic and
the concentration of this agent With certain classes of antibiotics (eg aminoglycosides
and fluoroquino-lones) the rate of killing increases with increased drug concentrations up
to a point of maximum effect This is termed concentration-dependent bactericidal activity
In contrast the killing rates of szlig-lactam agents and vancomycin are relatively slow and
continue only as long as the concentrations are in excess of the MIC This rate of killing is
termed time-dependent bactericidal activity
(2) The minimal concentration of drug needed to kill most of the viable organisms
after incubation for a fixed length of time (generally 24 hours) under a given set of
conditions is the most common estimation of bactericidal activity and is known as either
the minimal bactericidal concentration (MBC) or the minimal lethal concentration (MLC)
It will be referred to in this document as the MBC Unfortunately the definition of the
MBC (999 killing of the final inoculum) is somewhat arbitrary and separates the
bacteria into two populations ndash a segrega-tion which might not have biological relevance
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
29 Review of Literature
The determination of the MBC moreover is so subject to methodologic variables that the
clinical relevance of MBCs is nearly impossible to assess particularly for certain pathogen
and drug combinations (eg Staphylococci and beta-lactam agents)
(3) The serum of a patient receiving an antibiotic may be tested against the
infecting microorganism This can be done using time-kill curve methodology (ie serum
bactericidal rate) or using dilution methodology (ie serum bactericidal titer) The
principles of these methods as well as the influence of biological and technical factors are
similar (Barry et al 1999)
213 Microbial flora associated with deteriorated mural paintings
A great deal of research has been done in this field mainly by using cultivation dependent
methods However by using culture-dependent methods only a very small proportion of
microorganisms can be obtained Far less than 1 of organisms in the environment can be
cultivated by standard cultivation techniques (Pace 1996) Recent studies have shown that
culture-dependent techniques yielded mainly sporeforming bacteria suggesting that plating
leads to an over estimation of the number of spore-forming bacteria A wide number of
investigations have shown that in addition to chemical and physical processes
microorganisms play a major role in degradation of objects of art such as paintings stone-
works wood paper masonry leather parchment glass and metal (Ripka 2005)
A) Bacteria
In general growth of diverse organisms on mural paintings is supported by
humidity slight alkaline pH values and the presence of organic and inorganic nutrient
sources (Weirich 1989) In mural paintings pigments are suspended in water or oil often
binders such as casein and milk are used and they are supplied on the damp lime plaster
(Ciferri 1999) The calcium carbonate formed on contact with air consolidates the
pigments Thus frescos contain mainly inorganic components While chemoautotrophic
nitrifiers and thiobacilli obtain their energy for growth by oxidizing ammonium and
reducing sulphur-compounds respectively heterotrophic bacteria and fungi depend on
organically bound carbon [Tate et al (1991) Lazar (1971) Petushkova et al (1986)
Jimenez et al (1981)] Thus primary colonization of photoautotrophic Cyanobacteria
chemolithoautotrophic nitrifying bacteria and sulphuric acid producing thiobacilli represent
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
30 Review of Literature
the first supply of organic matter The death and lysis of such bacteria promotes the
secondary settlement of heterotrophic bacteria and fungal populations (Calvo et al 1991)
Bacteria may derive from plants or pollen as many sequences obtained in this study
gave high score similarities with bacteria isolated from plants like Moraxella osloensis
Enterobacter cloace Enterobacter agglomerans and Pantoea endophytica Bacteria may
also derive from animal faeces like flies Bacillus Pseudomonas Aeromonas and Panteoa
(Ripka 2005) As Lazar and Dumitru (1973) reported studying mural paintings in a
Romanian monastery the genera Bacillus Arthrobacter and Pseudomonas have been
proved to produce salt efflorescences and were even considered to cause the blanching
phenomenon of frescoes (Jimenez et al 2000) Predominant bacterial genera are Bacillus
Streptomyces Arthrobacter Micrococcus and Pseudomonas [Weirich (1989)
Tate et al (1990) Arroyo et al (1997) Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
B) Fungi
It may be concluded that there is wide variety of fungal forms present on mural
paintings but Aspergillus and Alternaria were found dominating from all the experimental
sites next to them were Cladosporium Drechestera Fusarium Curvularia Chaetomium
Memnoniella Mycelia sterelai Pencillium Emericella Stachybotrytis Trichoderma
Phoma Monodictys Humicola and Epicoccum (Garg et al 1995)
The fungal genera most commonly found in lists of isolated taxa given in literature
are Alternaria Aspergillus Chaetomium Cladosporium Fusarium Penicillium and
Verticullum [Weirich (1989) Tate et al (1990) Guglielminetti et al (1994)
Garg et al (1995) Berner et al (1997) Ciferri (1999)] Some fungi having hard fruiting
bodies represented by sclerotia pycnidia perithecia cleistothecia and stroma could
organize themselves inside the painted layer Many fungal forms having such structures
were identified from our experimental sites viz Emericella nidulans A flavus
Chaetomium sp and Phoma sp etc These structures with little increase in humidity may
cause swelling in the paint film (Garg 1995)
Strains of species of Alternaria and Cladosporium both of them identified on the
mural paintings of the Palace of Schoumlnbrunn are the most common genera isolated from
stone and mural paintings in indoor environments with standard cultivation methods
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
31 Review of Literature
(Ventosa 2004) Saprophytic species of the genus Cladosporium are among the most
abundant fungi isolated in saltern samples Commonly isolated Cyanobacteria belong to
Nostoc and eukaryotic algae to Lyngbya and members of the Chlorophyceae such as
Chlorella Pseudococcomyxa and Pseudopleurococcus [Gorbushina et al (1987)
Calvo et al (1993) Arino et al (1996)]
They grow optimally on media with low water activity due to high salt or sugar
concentrations seem to propagate 70 vegetatively in the salterns and are thus
halotolerantosmotolerant species rather than simple flush-through occurrences
Cladiosporum herbarum was frequently isolated from hypersaline waters dead and dying
plant material air soil food fruit cereals paint and textiles (Ventosa 2004)
C) Algae
Most of the painted areas in temperature climate became covered with green algae
(Pleurococcus Protococcus and Trentopholia) while under tropical conditions blue green
algae of the genera Oscillatoria and Sytonema predominated (Garg 1995) The main
factors which contribute to the growth of algae on wall paintings are the presence of
moisture in the plaster as well as availability of visible light These conditions are quite
prevalent in the tropical climate but in temperature regions also algal growth on wall
paintings have been reported [Tonolo et al (1961) Pietrini et al (1991)]
D) Actinomycetes
Usually literature refers to specific aspects eg the occurrence of cyanobacteria
and algae in caves with natural openings to sunlight or those with artificial lighting fungi
and so forth Actinomycetes have been considered to be mainly confined to soils where
they find their natural habitat but despite intensive studies there are still many gaps in our
knowledge of the role played by actinomycetes in soil processes and biodegrations of
murals cave paintings (Groth et al 1999) In addition halophilic bacteria actinomycetes
and cyanobacteria are also capable of growing on salt-affected mural paintings
(Karbowska 2003)
Monte and Ferrari (1993) reviewed the mechanisms of biodeterioration in tombs
and underground churches The role of actinomycetes in the deterioration of frescoes in
hypogean environments was stressed by Agarossi et al (1985) Monte and Ferrari (1993)
Giacobini et al (1987) described the serious damage suffered by a whole series of famous
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
32 Review of Literature
frescoes in underground environments Actinomycetes were isolated from these mural
paintings located in crypts caves and tombs About 200 strains of actinomycetes were
isolated 60 of which were identified The most frequent species were Streptomyces albus
S cinereoruber S griseolus S vinaceus and some members of the Nocardia genus
Heterotrophic bacteria and actinomycetes were the most abundant microorganisms
on the frescoes of Etruscan tombs (Agarossi et al 1985) Bettini et al (1977) studied
some of the oldest Etruscan tombs (7th to 4th century BC) and found white-grey patinas
and spots from streptomycetes in the mural paintings They related the biodeterioration to
the microclimatic conditions (eg lower temperatures high RH) Monte and Ferrari (1993)
considered that colonization of the mural paintings was the result of selective competitive
and inhibitory dynamics among different microorganisms under different and changing
environmental conditions The pigments excreted by some actinomycetes were responsible
for the violet stains found on the walls of tombs in Tarquinia Similar stains were observed
in one of the Roman tombs the Circular Mausoleum the Necropolis of Carmona Spain
from which a Streptomyces sp producing violet pigments in culture media was isolated
214 Identification of biodeteriogens
The possibility of pigments and biodeteriogens identification in frescos and stone
monitoring is offered mostly by vibrational spectroscopy infrared thermography laser
induced fluorescence (LIF) laser induced breakdown spectroscopy (LIBS) XRF (X-Ray
Fluorescence) IR and UV emission Among them laser based methods allowing for in
situ or remote characterization of artwork surface were applied successfully for
prospecting diagnosis and maintenance (Colao et al 2005) The rep-PCR fingerprinting
of the isolates allowed determination of their genotypic diversity Studies that have
compared rep-PCR genomic fingerprint analysis with DNAndashDNA relatedness studies have
shown that the two techniques yield results that are in close agreement [Nick et al (1999)
Rademaker et al (2000)] These studies therefore suggest that rep-PCR fingerprinting can
be used as a genomic screening method to differentiate at the species level and to select
representatives for DNAndashDNA reassociation experiments (Heymann et al 2003)
The characterisation of bacteria was for example often limited to isolation from
group-specific media followed by microscopy [Sorlini et al (1987) Weirich (1989)
Tate et al (1990) and in more recent studies to morphological and physiological
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
33 Review of Literature
characteristics including miniaturised and automated systems such as API and BIOLOG
[Arroyo et al (1997) Jimmenez et al (2000) and Laiz et al (2000)] or to
chemotaxonomic characteristics [Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
Wagner et al (1994) demonstrated that conventional microbiological efforts can
fail to isolate all microorganisms present in natural samples DNA-based techniques used
to identify microorganisms have revealed only a smaller fraction of bacteria isolated from
artworks (Ward et al 1990 Rolleke et al 1996) Bacterial identification using molecular
techniques especially those including the sequencing of genes coding for ribosomal
16S rRNA is very important to study bacterial communities found on artefacts One such
method is Denaturing Gradient Gel Electrophoresis (DGGE) of PCR-amplified gene
fragments coding for rRNA (Muyzer et al 1993) that allows the separation of partial
16S rDNA amplified fragments of identical length but different sequence due to their
different melting behaviour in a gel system containing a gradient of denaturants
(Jimenez 2003)
Total genomic DNA was purified for 16S rRNA gene sequencing and rep-PCR
using a slight modification of the method of Pitcher et al (1989) as described by
Heyndrickx et al (1996) rep-PCR genomic fingerprinting was performed with the REP-
and (GTG)5 primers (Versalovic et al 1994) using the PCR conditions described
previously by Rademaker et al (1997) Electrophoresis and pattern analysis were further
performed as described by Heyrman et al (2003) 16S rRNA gene sequencing and
phylogenetic analysis were performed as described by Heyrman and Swings (2001)
Phylogenetic trees were constructed using the BioNumerics software (Applied Maths) by
applying the neighbour-joining and maximum-parsimony methods on a multiple alignment
similarity matrix The stability of relationships was assessed by a bootstrap analysis of
1000 datasets For determination of the G+C content and levels of DNAndashDNA
hybridization approximately 1 g biomass was harvested from agar plates DNA was
purified by using a combination of the protocols of Marmur (1961) and
Pitcher et al (1989) as described by Logan et al (2000) The G+C content of the DNA
was determined by HPLC (Mesbah et al 1989) using the further specifications given by
Logan et al (2000) DNAndashDNA hybridization experiments were performed using a
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
34 Review of Literature
modification of the microplate method of Ezaki et al (1989) as described by
Willems et al (2001)
215 Preservation and conservation
Nowadays the conservation and preservation of our cultural heritage is one of the
world main concerns particularly in Europe The increasing need for non-destructive
investigation tools has become a major issue as sampling is in most cases restricted in
view of the value or the uniqueness of the object Artworks as wall paintings in buildings
and monuments of historical interest are affected by environment physical (temperature
and humidity) and biological factors (biodeteriogens) and by human (pollutant releases)
impact and therefore modified over the time The term ldquoconservationrdquo may have many
different meanings in different fields Every intervention directed to the restoration and
safeguard of works of art is commonly considered as a conservation treatment For
example conservation can involve the cleaning procedures set up by chemists or the photo
documentation of the preservation of historical memory For the appropriate conservation
of works of art even the lighting systems in a museum or the control of the visitorrsquos
movements in a site should be monitored Chemical degradation which induces the flaking
of paintings and deterioration from rain wind dust and other environmental causes is
mainly responsible for the weakening of the porous structure and the surface layers of the
materials used in works of cultural heritage (Colao et al 2005)
216 Conservation history
Wall paintings are an integral part of monuments and sites and should be preserved
in situ Many of the problems affecting wall paintings are linked to the poor condition of
the building or structure its improper use lack of maintenance frequent repairs and
alterations Also frequent restorations unnecessary uncovering and use of inappropriate
methods and materials can result in irreparable damage Substandard and inadequate
practices and professional qualifications have led to unfortunate results It is for this reason
that an appropriate document covering the principles of proper conservation-restoration of
wall paintings is necessary
The Venice Charter (1964) has provided general principles for the conservation-
restoration of cultural heritage The Amsterdam Declaration (1975) introducing the
concept of integrated conservation and the Nara Document on Authenticity (1994) dealing
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
35 Review of Literature
with cultural diversity have expanded these principles Taking into account these and
additional relevant contributions such as the ICOM-CC Code of Ethics (1984) Document
of Pavia (1997) and ECCO Professional Guidelines (1997) the aim of this document is
to provide more specific principles for the protection preservation and the conservation
restoration of wall paintings This document therefore reflects basic and universally
applicable principles and practices and does not take into account particular problems of
regions or countries which can be supplemented at regional and national level by
providing further recommendations where necessary
217 Preservation techniques of the mural paintings
The removal of fat salts varnishes and pollutants from the surfaces of the works
of art are mostly done by chemical and mechanical methods At the end of the 19th
century the practices of restoration methods that do not inhibit further future interventions
was considered acceptable During the 1960s several chemicals such as polymeric resins
were synthesized and applied as a consolidation or protection agents The accepted idea
was that these substances could be removed at any time leaving a completely unaltered
substrate On the basis of origin archaeological objects can be classified as follows
(Carretti 2005)
1 Inorganic It includes siliceous and nonsiliceous materials Archaeological materials
produced from stones terracotta ceramics and glass can be included under siliceous
materials whereas objects made of metals can be included under nonsiliceous inorganic
materials Again metal objects can be classified as ferrous metals and non-ferrous metals
Objects made of iron are termed as ferrous metal objects whereas metal objects made from
other than iron is termed as non-ferrous metal objects
2 Organic It includes archival and anthropological materials Again archival materials
include paper bhojapatra tadapatra textiles wooden objects miniature paintings whereas
anthropological objects include bone and ivory leather feather and fur etc
In the past restoration of paintings and other old artwork often involved application
of acrylic resins to consolidate and protect them One of the most important tasks for
modern restorers is thus to remove these layers because it turns out that acrylic resins not
only by drastically changing the optics of the treated artwork but in many cases they
accelerate their degradation The scientists use an oil-in-water microemulsion with the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
36 Review of Literature
organic solvent para-xylene as the oil component The matrix makes the cleaning agent
viscous so that it cannot enter very far into the pores of a painting (Carretti 2005)
Nanoparticle treatment is the logical evolution of the Ferroni-Dini method
Dispersions of kinetically stable Ca (OH)2 nanoparticles in non-aqueous solvents solved
most of the drawbacks of the microsized powders Stable dispersions of calcium hydroxide
have been successfully applied (replacing polymers) as fixatives to re-adhere lifted paint
layers during many restoration workshops in Italy and in Europe as a consolidant The
FerronindashDini method (two steps the application of a saturated solution of ammonium
carbonate (NH4)2CO3 and the treatment with a barium hydroxide solution Ba(OH)2 also
called the barium method has long been the acknowledged method for the removal of
salts that threaten paintings reinforcing at the same time the porous structure However
commercially available carbonates and hydroxide powders have dimensions of several
micrometres much larger than the pores on the paint surface This means they donrsquot
penetrate the painting well and there is also a risk of damaging the artwork by a white
glaze forming on the surface (Berger 2006) Restoration should provide the reinforcement
of the porous structure and the consolidation of the surface layer of arte facts A few
simple principles can be considered to define the most appropriate restoration method
1) The treatment should be reversible so that one can revert to the original status of the
work of art at any desired time
2) All the applied chemicals must ensure the maximum durability and the chemical
inertness
3) The applied chemicals must invert the degradation processes without altering the
chemical composition of the artefacts and their physico-chemical and mechanical
properties (Baglioni 2006)
218 Commercial preservative used for preservation of mural paintings
Cleaning was done using soft brushes vacuum cleaner and Gumma paine (dough)
a natural latex sponge Areas near the window were very dirty with black soot and were
cleaned with micro fibrous cloths moistened with synperonic N (surfactant alkyl phenol
ethoxylate based on nonyl phenol) and neutralized with clean water In several places the
paint layers had separated from the substrate (exfoli-ation) In that cases loose paint flakes
were stuck back using Paraloid B72 (10 solution in ethanol) as sparingly as possible
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
37 Review of Literature
Paraloid was injected with syringe behind the exfoliated area twice pushed and held back
with Melinex (polyester film) until fixed on the third application (Bionda et al 2002)
In a period of significant growth of molds and intensive efforts to stop the mold
contamination some of the lines of certain paintings were obscured or faded Solutions of
ethanol formalin 91 and Thiabendazole (TBZ) were used but they were not very
effective Para-formaldehyde fumigation was adopted beginning in 1981 to establish an
emergency treatment sensitivity of microorganisms from studied samples was tested
against Desogen by adding 1-3 (v v) in serial dilutions The best concentration
3 (vv) was applied with a brush to prevent spreading of the spores In order to overcome
the problem of fungal attack suitable fungicides carbendizeme or kiroxy-I or 5 solute of
N formaldehyde can be used Shellac solution in spirit or 2 solution of polyvinaycletate
in toluene can be used as preservative and consolidantsTo control insect and fungal attack
fumigants like pyrethrum DDT or 5 solution of sodium penta chlorophenate in kerosene
oil 2 to 5 solution of PVA in toluene or 2 to 5 solution of paraloid B-72 in toluene or
acetone be used (Miura 2009) Microclimatic conditions constitute a critical factor in the
conservation of cave paintings The unstable microclimatic condition is one of the factors
that always affect the state of conservation of mural paintings In the environmental-
monument system knowledge of the functional environment and climatic conditions of the
surroundings are necessary for the identification of causes of decay (Singh 2011)
Furthermore the risk of formation of indoor bioaerosols in residential and public
buildings (offices schools museums etc) has attracted interest in the last years due to
socio-economic as well as sanitary reasons (Ripka 2005) Thus it is important in aspects of
health and maintenance of Cultural Heritage to analyse the complete microflora to further
develop biocides for harmful microorganisms and methods for restoration of damaged
objects of art The biocidal testing was carried out on one representative algal species of
the two classes of algae viz Chlorococcum sp (green) and Chroococcus sp (blue-green)
found to be common in all the samples Efficiency tests were carried out both in liquid as
well as solid media containing algal suspensions by adding a biocide solution of known
concentration and determining the growth of the microorganism after the incubation
period The biocides used for the past studies were
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
21 Review of Literature
almost an equal number their wild relatives Thus India harbours a wealth of useful
germplasm resources and there is no doubt that the plant kingdom is a treasure-house of
diverse natural products One such product from nature is the dye (Siva 2007)
Many natural dyestuff and stains were obtained mainly from plants and dominated
as sources of natural dyes producing different colours like red yellow blue black brown
and a combination of these Almost all parts of the plants like root bark leaf fruit wood
seed flower etc produce dyes It is interesting to note that over 2000 pigments are
synthesized by various parts of plants of which only about 150 have been commercially
exploited Nearly 450 taxa are known to yield dyes in India alone of which 50 are
considered to be the most important ten of these are from roots four from barks five from
leaves seven from flowers seven from fruits three from seeds eight from wood and three
from gums and resins Some important dye-yielding plant habitats their distribution and
colouring pigment (Siva 2007)
The dye is generally prepared by boiling the crushed powder with water but
sometimes it is left to steep in cold water The solution then obtained is used generally to
dye coarse cotton fabrics Alum is generally used as a mordant Flowers of Butea
monosperma (Lam) Taubert yield an orange-coloured dye which is not fast and is easily
washed away For the purpose of colouring the material is steeped in a hot or cold
decoction of the flowers A more permanent colour is produced either by first preparing the
cloth with alum and wood ash or by adding these substances to the dye-bath The dye
indigo is produced by steeping the plant in water and allowing it to ferment This is
followed by oxidation of the solution with air in a separate vessel Mallotus philippinensis
muell yields an orange colour used for dyeing silk and wool To prepare the annatto dye
from B orellena the fruits are collected when nearly ripe The seeds and pulp are removed
from the mature fruit and macerated with water Thereafter they are either ground up into
an lsquoannatto pastersquo or dried and marketed as annatto seeds Sometimes when the seeds and
pulp are macerated with water the product is stained through a sieve and the colouring
matter which settles out is collected and partially evaporated by heat and finally dried in
the sun (Sowbhagya 2002)
The predominant colors used in rock art and cave art are black (from charcoal soot
or manganese oxide) yellow ochre (limonite) red ochre (hematite or baked limonite) and
white (kaolin clay burnt shells powdered gypsum or powdered calcium carbonate) All of
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
22 Review of Literature
theses pigments may be used on leather or raw hide as well Early cave art in Seminole
Canyon was monochromatic in red and as culture grew more sophisticated the color
palette expanded Blue Orange Brown Green and Purple are the most common colours
used in Ajantha murals White Pink Gold are occasionally represented mineral earths
containing ferric oxide and copper carbonates were used as source of red yellow and green
colours There is also evidence to establish that root of Rubia cardifolia and leaves of
Indigofera tinctoria were used as source for red and blue colours (Nayer et al 1999)
Many colors of pigments were obtained from both organic and inorganic sources in
ancient times and used to paint various surfaces such as braintan leather clothing and
accoutrements rawhide the human body etc Blue color was obtained from powdered
azurite and lapis duck manure and certain clays Fine Blue-green clay was obtained from
deposits near Mankato Michigan Organic sources of blue include Turkeys Tail a
greenish blue polypore that grows on dead decaying wood (not tannish ones) Native
Americans get Indigo from either Guatemala or Ecuador which was traded well up onto
Kansas long before the Spanish ever set foot here American Indigo has purple tones to it
but IndianJapanese indigo has green tones Berries and crushed flowers were also used to
obtain blue color by rubbing the plant material directly on the leather
An organic source of red was Cochineal It was native west of the Mississippi and
is produced from the bodies of small insects that grow on the prickly pear cactus Ladys
Bedstraw gives a good vermillion red color Harvest the roots dry them out clean the mud
etc off of them and then grind the roots really fine then soak them to extract the red
coloring The key here is drying the root first Blood was also used as red pigment Pucoon
roots also yield a red pigment (Smith 2002) Red ochre the reverse original red colours are
due to variations in iron oxide (or) calcite content and to redox conditions in the firing
produced Brown coloured ceramics owe their colour to maghemite and must be
considered as a fabrication defect due to the position of the ceramic piece in a zone where a
reducing atmosphere prevailed in the course of firingRed pigments were produced from
iron oxides like hematite or limonite and from ochre Hematite was the most frequently
used mineral It occurs in the form of aggregates of small red crystals or in the form of
bigger black crystals which are difficult to crush white was obtained mostly from
kaolinite or illite (Clottes et al 1990)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
23 Review of Literature
210 Biodetoriation of mural paintings
Historic items often contain natural biodegradable materials and have histories of
exposure to moist conditions These two conditions make them amenable to microbial
attack Microbial colonization may damage the building or the cultural asset
(Salonen 2001) Biodeteriogens are organisms involved in deterioration of artifacts They
are very specific for each type of artifact in accordance with its chemical structure and
environment They also have different nutritional requirements and act directly or
indirectly on the substrate The adhesion of microorganisms to a substrate is the result of
cell hydrophobicity and of excreted polymeric substances contained by sheaths capsules
and slimes (Colao 2005)
The surviving wall paintings and decorations in subterranean environments around
Malta are rather scarce (Buhagiar 1986 1993 1998) These include those at St Paulrsquos
Catacombs (Zammit 2008) St Agatharsquos Crypt and Catacombs (Camilleri 2001)
San Catald Catacombs Tac-Cghaqi Abbatija tad-Dejr (Buhagiar 1993) all in Rabat the
cave-sanctuary in Mellieħa (Buhagiar 1987) and the Ħal Saflieni Hypogeum in Paola
(Pace 2000) Previous studies conducted on wall paintings and decorations in Maltese
Palaeo-Christian Catacombs have involved their manufacturing techniques (Muscat 2005)
However to date limited systematic studies have been conducted into the biodeterioration
in Maltese Palaeo- Christian Catacombs The only such studies ever conducted in Malta
concerned the biodeterioration of works of art in catacombs have been carried out at St
Agatharsquos Crypt and Catacombs in Rabat (Zammit et al 2008 Psaila 2006)
Microorganisms can be responsible for the destruction of monuments buildings
and cultural heritage assets including the decay of concrete cement stones mural
paintings etc These microorganisms are not only related with biodeterioration but water-
damaged indoor building materials are frequently colonized by complex bacterial
communities and may emit mixed bioaerosols into the indoor air (Jimenez 2000) It is
well known that mural paintings are colonized by micro-organisms and can be severely
damaged by such growths (Ciferri 1999) A large number of fungal (gt50) and bacterial
taxa (70) have been detected in indoor environments Over 50 bacterial species and 14
genera novel to science were reported in the past 10 years from indoor air and historic
items indicating bacterigravea in these enviroments are as yet only fragmentarily known
(Salonen 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
24 Review of Literature
Traditionally the study of microflora which causes this biodeterioration was based
on classical cultivation methods that were mainly useful to study the physiological
potential of microorganisms but do not provide information on all microbial communities
to be found in excavated artifacts Indeed many studies using culture-independent
techniques which cultivate microorganisms from different environments may often
represent only minor components of the microbial community as a whole It is generally
accepted that cultivation methods recover less than 1 of the total microorganisms present
in environmental samples (Ward et al 1990 Amann et al 1995) Hence microbial
investigations based only on cultivation strategies cannot be regarded as reliable in terms
of reflecting the microbial diversity present in objects of art (Osburn et al 2011)
Early workers suggested that the presence of living microorganisms on stone
increased its susceptibility to damage through their water-binding capacity It has recently
been reported that the mineralogy porosity surface roughness and capacity to collect
water and organic materials control its bioreceptivity and tendency to biodeterioration
(Diakumaku 1995) In addition environmental factors as temperature light pH and
relative humidity affect the number and type of colonising species (Tiano et al 1995) and
hence the progress of colonisation Biofilms on decayed stones consist on mixed microbial
populations embedded in a polymeric matrix Fungi algae filamentous and unicellular
bacteria are found in these complex communities A variety of bacteria have been isolated
from different stone samples confirming the dominance of Gram-positive organisms
especially spore-forming bacteria such as Bacillus and filamentous actinomycetes
(Ripka 2005)
In cultivation studies of deteriorated mural and rock paintings bacterial isolates
have frequently been attributed to the genus Bacillus (Weirich 1989 Tate and Rebrikova
1991 Gonzalez et al 1999 Heyrman et al 1999 Jimenez et al 2000) Other studies that
have included DNA-based techniques to characterize the bacterial community involved in
biodeterioration have shown that a substantial part of the bacterial population is made up of
so far unknown species (Altenburger et al 1996 Rolleke et al 1996 Gurtner et al 2000
Heyrman and Swings 2001) (Heymann et al 2003)
Many potential mycotoxin producers have been detected in air and items from
indoor environments with histories of exposure to moisture for example species of
Acremonium Alternaria Aspergillus Chateomium Fusarium Eurotium Paecilomyces
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
25 Review of Literature
Penicillium Scopulariopsis Stachybotrys Trichoderma Verticillium and Wallemia
(Peltola et al 2001 Pieckova et al 2001) Not all strains of one species produce
mycotoxins and different strains may produce different toxins Whereas toxin producing
strains are frequent in crops and outdoor vegetation toxin producing isolates from indoor
environments and non living assets have only been reported of the species Aspergillus
versicolor (Nielsen et al 1998) Stachybotrys chartarum Nikulin (1997) and
Trichoderma harzianum (Peltola et al 2001) Streptomyces griseus strains producing
valinomycin occur in environments where humans can get exposed
(Andersson et al 2002) The biological properties and toxicity mechanisms of cereulide
were identical to those by valinomycin (Mikkola et al 1999 Salonen et al 2001)
The genus Paenibacillus was first proposed by Ash et al (1993) and its description
was emended by Shida et al (1997) The genus Paenibacillus is under intensive taxonomic
investigation with ten species having been formally described in the last year Heyrman amp
Swings (2001) isolated a strain originally classified as Paenibacillus sp LMG 19508
from biodeteriorated mural paintings in the Servilia tomb at the Roman necropolis of
Carmona in Seville Spain (Smerda et al 2006) Building stone and wall paintings contain
a variety of hydroscopic salts including carbonates chlorides nitrates sulfates etc
dispersed within the porous material or locally concentrated These salts are solubilised
and migrate with the water in and out of the stone Due to changes in physical parameters
the so called salt efflorescences appear on the surfaces providing extremely saline
environments and building niches for settlement of halophilic microorganisms Halite and
other hygroscopic salts can retain considerable quantities of moisture when entrapped in
the building materials and thus favouring the bacterial growth (Ripka 2005)
It is demonstrated that water-damaged indoor building materials contained
substances of microbial origin extremely toxic to eukaryotic cells and large quantities of
several microbial species known to be potentially toxic or immunopotentiating These
include peptidoglycans Gram-negative endotoxin β-13-D glucans lipoglycans and
teichoic acids and mycotoxins (Jimenez 2000) In turn these microorganisms can mediate
the crystallization process These crystallizations can produce destructive effects Some
salts may crystallize or recrystallize to different hydrates which occupy a larger space and
exert additional pressure producing cracking powdering and flaking
(Jimenez and Laiz 2000)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
26 Review of Literature
211 Types of deterioration on mural paintings
The frescos represent a variety of ecological niches where primary colonization is
due to photoautotrophic and chemolithoautotrophic microorganisms followed by
secondary colonization due to heterotrophic bacteria that obtain nutrients from various
sources (metabolites of autotrophic bacteria airborne organic contamination animal faeces
and organic compounds in the paint layers themselves) Microbial-induced deterioration
processes cause structural as well as aesthetic damage to wall paintings such as the
discoloration of materials the formation of crusts on surfaces and the loss of material
(Sarro et al 2006 Osburn et al 2011) Halophilic bacteria and archaea were thought to
be found only in extreme environments like salt lakes or black smokers However it has
been shown that mural paintings and stones are a common habitat for extremely salt
tolerant and moderate halophilic (Ripka 2005) Microbial induced deterioration processes
can cause different kinds of alterations such as discolouration of materials the formation of
crusts on surfaces and the loss of material which leads to structural damage (Ripka 2005)
First of all microorganisms can cause severe problems due to the excretion of aggressive
metabolic products such as organic or inorganic acids Secondly material components can
be used as substrates for microbial metabolism Exoenzymes such as cellulases proteases
tannases beta-glucosidase produced by fungi and bacteria are responsible for hydrolysis of
cellulose and proteins Further examples are mechanical processes caused by swelling and
shrinking of slime or mycelia penetrating inside plaster of the painting resulting in loss of
cohesion and detachment of the paint layer (Rolleke 1996 Gurtner et al 2000)
Table-21 Microbial damage on mural paintings (Rolleke 1996)
S No Damage Microbial activity
1 Green brown red grey
surface layers (patinas)
Pigments produced by microorganisms (intra-or
extracellular) as chlorophyll and carotinoids
2 Dislodging of painting layers Use of organic binders as nutrient and energy
source
3 Acid attack of carbonates Acid produced by fungi or bacteria
4 Discolouration of pigments Redox-reactions induced by fungi and
bacteria
5 Loss of paint layer Growth of microorganisms deep into the plaster
6 Hydrolysis of synthetic
polymers Chemoorganotrophic activity of bacteria and fungi
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
27 Review of Literature
Discolorations are caused by excretion of pigments and microbiologically induced
reductionoxidation-processes (Krumbein et al 1990) Degradation of the bindings is
followed by reduction of stability Oxidation of ammonium and reduced sulphur
compounds results in acidification of the environment such as Sulphuric acid and the
variety of organic acids produced by the heterotrophs cause solubilization of calcareous
binding material and chelation of metal ions (Bock et al 1993) It is now well recognised
that wall paintings can be deteriorated by microorganisms (Ciferri 1999)The growth of
microorganisms essentially results in two types of damage aesthetic and structural
Aesthetic damage implies pigment discoloration stains and formation of a biofilm on the
painted surface Structural damage is observed as cracking and disintegration of the paint
layer formation of paint blisters and degradation of support polymers or of glues and
binders resulting in detachment of paint layer from the support The colonization of mural
paintings by bacteria and other microorganisms can have different causes Provided that
favorable environmental conditions occur nutrients for heterotrophic bacteria and fungi
can be available from metabolites of autotrophic bacteria from airborne contamination and
dripping water from animal faeces but also from organic compounds in the paint layer
itself
212 Methods of studying biodeterioration
It is now well recognized that wall paintings may be deteriorated by
microorganisms as established by several studies that linked the observed damage with the
microbial community present as reviewed by Ciferri (1999) Despite this knowledge a
reliable characterization of bacteria associated with such damage is often lacking To
obtain greater insight into the bacterial community involved in biodeterioration of mural
paintings three sites (from the necropolis at Carmona Spain and the Saint-Catherine
chapel of the castle at Herberstein Austria) were sampled In previous studies from these
sites 385 isolates were analysed by fatty acid methyl ester GC and representatives of
different fatty acid clusters were further studied by 16S rRNA gene sequencing
(Heyrman and Swings 2001) Several of these representative strains showed the highest
sequence similarity with members of the genus Arthrobacter (Heyrman et al 2005)
Jimenez and Samson (1981) analysed the microbial flora of a large fresco painted
in the late 1920s in the monastery ldquoSanta Maria de la Rabidardquo (Huelva Spain) exhibiting
two types of deterioration white efflorescence and green-to-black stains
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
28 Review of Literature
Tate and Rebrikova (1990) thought autotrophic nitrifying bacteria to be the first colonisers
of damaged frescoes and building materials in the cathedral of the nativity of the Virgin in
the Pafnutii-Borovskii monastery (Russia) The bulk of research on biodeterioration of
mural paintings has focused on explaining the observed phenomena by analysing the
microflora present Following this approach a precise characterisation of the
microorganisms using a polyphasic approach was never the first goal
Only a few studies included genomic fingerprinting (16S rDNA sequence analysis)
for the characterisation of bacteria associated with damage on mural paintings
[Rolleke (1996) Pinar et al (2001)] Previous studies based on culture-dependent
techniques showed that the flora present on frescos are fungi (predominant species of
Penicillium Aspergillus Cladosporium and Engyodontium) (Guglielminetti et al 1994)
bacteria (predominant species of Bacillus Arthrobacter Micrococcus Streptomyces and
Pseudomonas) (Heyrman et al 1999) cyanobacteria and eukaryotic algae (species of
Nostoc Lyngbya and Chlorophyceae) (Arino et al 1996 Calvo et al 1993) The killing
effect of an antimicrobial agent on a microorganism can be assessed in several ways
(1) Lethal activity may be expressed as the rate of killing by a fixed concentration
of drug under controlled conditions This rate is determined by measuring the number of
viable bacteria at various time intervals The resulting graphic depiction is known as the
time-kill curve Bacterial killing rates are in part dependent on the class of antibiotic and
the concentration of this agent With certain classes of antibiotics (eg aminoglycosides
and fluoroquino-lones) the rate of killing increases with increased drug concentrations up
to a point of maximum effect This is termed concentration-dependent bactericidal activity
In contrast the killing rates of szlig-lactam agents and vancomycin are relatively slow and
continue only as long as the concentrations are in excess of the MIC This rate of killing is
termed time-dependent bactericidal activity
(2) The minimal concentration of drug needed to kill most of the viable organisms
after incubation for a fixed length of time (generally 24 hours) under a given set of
conditions is the most common estimation of bactericidal activity and is known as either
the minimal bactericidal concentration (MBC) or the minimal lethal concentration (MLC)
It will be referred to in this document as the MBC Unfortunately the definition of the
MBC (999 killing of the final inoculum) is somewhat arbitrary and separates the
bacteria into two populations ndash a segrega-tion which might not have biological relevance
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
29 Review of Literature
The determination of the MBC moreover is so subject to methodologic variables that the
clinical relevance of MBCs is nearly impossible to assess particularly for certain pathogen
and drug combinations (eg Staphylococci and beta-lactam agents)
(3) The serum of a patient receiving an antibiotic may be tested against the
infecting microorganism This can be done using time-kill curve methodology (ie serum
bactericidal rate) or using dilution methodology (ie serum bactericidal titer) The
principles of these methods as well as the influence of biological and technical factors are
similar (Barry et al 1999)
213 Microbial flora associated with deteriorated mural paintings
A great deal of research has been done in this field mainly by using cultivation dependent
methods However by using culture-dependent methods only a very small proportion of
microorganisms can be obtained Far less than 1 of organisms in the environment can be
cultivated by standard cultivation techniques (Pace 1996) Recent studies have shown that
culture-dependent techniques yielded mainly sporeforming bacteria suggesting that plating
leads to an over estimation of the number of spore-forming bacteria A wide number of
investigations have shown that in addition to chemical and physical processes
microorganisms play a major role in degradation of objects of art such as paintings stone-
works wood paper masonry leather parchment glass and metal (Ripka 2005)
A) Bacteria
In general growth of diverse organisms on mural paintings is supported by
humidity slight alkaline pH values and the presence of organic and inorganic nutrient
sources (Weirich 1989) In mural paintings pigments are suspended in water or oil often
binders such as casein and milk are used and they are supplied on the damp lime plaster
(Ciferri 1999) The calcium carbonate formed on contact with air consolidates the
pigments Thus frescos contain mainly inorganic components While chemoautotrophic
nitrifiers and thiobacilli obtain their energy for growth by oxidizing ammonium and
reducing sulphur-compounds respectively heterotrophic bacteria and fungi depend on
organically bound carbon [Tate et al (1991) Lazar (1971) Petushkova et al (1986)
Jimenez et al (1981)] Thus primary colonization of photoautotrophic Cyanobacteria
chemolithoautotrophic nitrifying bacteria and sulphuric acid producing thiobacilli represent
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
30 Review of Literature
the first supply of organic matter The death and lysis of such bacteria promotes the
secondary settlement of heterotrophic bacteria and fungal populations (Calvo et al 1991)
Bacteria may derive from plants or pollen as many sequences obtained in this study
gave high score similarities with bacteria isolated from plants like Moraxella osloensis
Enterobacter cloace Enterobacter agglomerans and Pantoea endophytica Bacteria may
also derive from animal faeces like flies Bacillus Pseudomonas Aeromonas and Panteoa
(Ripka 2005) As Lazar and Dumitru (1973) reported studying mural paintings in a
Romanian monastery the genera Bacillus Arthrobacter and Pseudomonas have been
proved to produce salt efflorescences and were even considered to cause the blanching
phenomenon of frescoes (Jimenez et al 2000) Predominant bacterial genera are Bacillus
Streptomyces Arthrobacter Micrococcus and Pseudomonas [Weirich (1989)
Tate et al (1990) Arroyo et al (1997) Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
B) Fungi
It may be concluded that there is wide variety of fungal forms present on mural
paintings but Aspergillus and Alternaria were found dominating from all the experimental
sites next to them were Cladosporium Drechestera Fusarium Curvularia Chaetomium
Memnoniella Mycelia sterelai Pencillium Emericella Stachybotrytis Trichoderma
Phoma Monodictys Humicola and Epicoccum (Garg et al 1995)
The fungal genera most commonly found in lists of isolated taxa given in literature
are Alternaria Aspergillus Chaetomium Cladosporium Fusarium Penicillium and
Verticullum [Weirich (1989) Tate et al (1990) Guglielminetti et al (1994)
Garg et al (1995) Berner et al (1997) Ciferri (1999)] Some fungi having hard fruiting
bodies represented by sclerotia pycnidia perithecia cleistothecia and stroma could
organize themselves inside the painted layer Many fungal forms having such structures
were identified from our experimental sites viz Emericella nidulans A flavus
Chaetomium sp and Phoma sp etc These structures with little increase in humidity may
cause swelling in the paint film (Garg 1995)
Strains of species of Alternaria and Cladosporium both of them identified on the
mural paintings of the Palace of Schoumlnbrunn are the most common genera isolated from
stone and mural paintings in indoor environments with standard cultivation methods
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
31 Review of Literature
(Ventosa 2004) Saprophytic species of the genus Cladosporium are among the most
abundant fungi isolated in saltern samples Commonly isolated Cyanobacteria belong to
Nostoc and eukaryotic algae to Lyngbya and members of the Chlorophyceae such as
Chlorella Pseudococcomyxa and Pseudopleurococcus [Gorbushina et al (1987)
Calvo et al (1993) Arino et al (1996)]
They grow optimally on media with low water activity due to high salt or sugar
concentrations seem to propagate 70 vegetatively in the salterns and are thus
halotolerantosmotolerant species rather than simple flush-through occurrences
Cladiosporum herbarum was frequently isolated from hypersaline waters dead and dying
plant material air soil food fruit cereals paint and textiles (Ventosa 2004)
C) Algae
Most of the painted areas in temperature climate became covered with green algae
(Pleurococcus Protococcus and Trentopholia) while under tropical conditions blue green
algae of the genera Oscillatoria and Sytonema predominated (Garg 1995) The main
factors which contribute to the growth of algae on wall paintings are the presence of
moisture in the plaster as well as availability of visible light These conditions are quite
prevalent in the tropical climate but in temperature regions also algal growth on wall
paintings have been reported [Tonolo et al (1961) Pietrini et al (1991)]
D) Actinomycetes
Usually literature refers to specific aspects eg the occurrence of cyanobacteria
and algae in caves with natural openings to sunlight or those with artificial lighting fungi
and so forth Actinomycetes have been considered to be mainly confined to soils where
they find their natural habitat but despite intensive studies there are still many gaps in our
knowledge of the role played by actinomycetes in soil processes and biodegrations of
murals cave paintings (Groth et al 1999) In addition halophilic bacteria actinomycetes
and cyanobacteria are also capable of growing on salt-affected mural paintings
(Karbowska 2003)
Monte and Ferrari (1993) reviewed the mechanisms of biodeterioration in tombs
and underground churches The role of actinomycetes in the deterioration of frescoes in
hypogean environments was stressed by Agarossi et al (1985) Monte and Ferrari (1993)
Giacobini et al (1987) described the serious damage suffered by a whole series of famous
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
32 Review of Literature
frescoes in underground environments Actinomycetes were isolated from these mural
paintings located in crypts caves and tombs About 200 strains of actinomycetes were
isolated 60 of which were identified The most frequent species were Streptomyces albus
S cinereoruber S griseolus S vinaceus and some members of the Nocardia genus
Heterotrophic bacteria and actinomycetes were the most abundant microorganisms
on the frescoes of Etruscan tombs (Agarossi et al 1985) Bettini et al (1977) studied
some of the oldest Etruscan tombs (7th to 4th century BC) and found white-grey patinas
and spots from streptomycetes in the mural paintings They related the biodeterioration to
the microclimatic conditions (eg lower temperatures high RH) Monte and Ferrari (1993)
considered that colonization of the mural paintings was the result of selective competitive
and inhibitory dynamics among different microorganisms under different and changing
environmental conditions The pigments excreted by some actinomycetes were responsible
for the violet stains found on the walls of tombs in Tarquinia Similar stains were observed
in one of the Roman tombs the Circular Mausoleum the Necropolis of Carmona Spain
from which a Streptomyces sp producing violet pigments in culture media was isolated
214 Identification of biodeteriogens
The possibility of pigments and biodeteriogens identification in frescos and stone
monitoring is offered mostly by vibrational spectroscopy infrared thermography laser
induced fluorescence (LIF) laser induced breakdown spectroscopy (LIBS) XRF (X-Ray
Fluorescence) IR and UV emission Among them laser based methods allowing for in
situ or remote characterization of artwork surface were applied successfully for
prospecting diagnosis and maintenance (Colao et al 2005) The rep-PCR fingerprinting
of the isolates allowed determination of their genotypic diversity Studies that have
compared rep-PCR genomic fingerprint analysis with DNAndashDNA relatedness studies have
shown that the two techniques yield results that are in close agreement [Nick et al (1999)
Rademaker et al (2000)] These studies therefore suggest that rep-PCR fingerprinting can
be used as a genomic screening method to differentiate at the species level and to select
representatives for DNAndashDNA reassociation experiments (Heymann et al 2003)
The characterisation of bacteria was for example often limited to isolation from
group-specific media followed by microscopy [Sorlini et al (1987) Weirich (1989)
Tate et al (1990) and in more recent studies to morphological and physiological
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
33 Review of Literature
characteristics including miniaturised and automated systems such as API and BIOLOG
[Arroyo et al (1997) Jimmenez et al (2000) and Laiz et al (2000)] or to
chemotaxonomic characteristics [Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
Wagner et al (1994) demonstrated that conventional microbiological efforts can
fail to isolate all microorganisms present in natural samples DNA-based techniques used
to identify microorganisms have revealed only a smaller fraction of bacteria isolated from
artworks (Ward et al 1990 Rolleke et al 1996) Bacterial identification using molecular
techniques especially those including the sequencing of genes coding for ribosomal
16S rRNA is very important to study bacterial communities found on artefacts One such
method is Denaturing Gradient Gel Electrophoresis (DGGE) of PCR-amplified gene
fragments coding for rRNA (Muyzer et al 1993) that allows the separation of partial
16S rDNA amplified fragments of identical length but different sequence due to their
different melting behaviour in a gel system containing a gradient of denaturants
(Jimenez 2003)
Total genomic DNA was purified for 16S rRNA gene sequencing and rep-PCR
using a slight modification of the method of Pitcher et al (1989) as described by
Heyndrickx et al (1996) rep-PCR genomic fingerprinting was performed with the REP-
and (GTG)5 primers (Versalovic et al 1994) using the PCR conditions described
previously by Rademaker et al (1997) Electrophoresis and pattern analysis were further
performed as described by Heyrman et al (2003) 16S rRNA gene sequencing and
phylogenetic analysis were performed as described by Heyrman and Swings (2001)
Phylogenetic trees were constructed using the BioNumerics software (Applied Maths) by
applying the neighbour-joining and maximum-parsimony methods on a multiple alignment
similarity matrix The stability of relationships was assessed by a bootstrap analysis of
1000 datasets For determination of the G+C content and levels of DNAndashDNA
hybridization approximately 1 g biomass was harvested from agar plates DNA was
purified by using a combination of the protocols of Marmur (1961) and
Pitcher et al (1989) as described by Logan et al (2000) The G+C content of the DNA
was determined by HPLC (Mesbah et al 1989) using the further specifications given by
Logan et al (2000) DNAndashDNA hybridization experiments were performed using a
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
34 Review of Literature
modification of the microplate method of Ezaki et al (1989) as described by
Willems et al (2001)
215 Preservation and conservation
Nowadays the conservation and preservation of our cultural heritage is one of the
world main concerns particularly in Europe The increasing need for non-destructive
investigation tools has become a major issue as sampling is in most cases restricted in
view of the value or the uniqueness of the object Artworks as wall paintings in buildings
and monuments of historical interest are affected by environment physical (temperature
and humidity) and biological factors (biodeteriogens) and by human (pollutant releases)
impact and therefore modified over the time The term ldquoconservationrdquo may have many
different meanings in different fields Every intervention directed to the restoration and
safeguard of works of art is commonly considered as a conservation treatment For
example conservation can involve the cleaning procedures set up by chemists or the photo
documentation of the preservation of historical memory For the appropriate conservation
of works of art even the lighting systems in a museum or the control of the visitorrsquos
movements in a site should be monitored Chemical degradation which induces the flaking
of paintings and deterioration from rain wind dust and other environmental causes is
mainly responsible for the weakening of the porous structure and the surface layers of the
materials used in works of cultural heritage (Colao et al 2005)
216 Conservation history
Wall paintings are an integral part of monuments and sites and should be preserved
in situ Many of the problems affecting wall paintings are linked to the poor condition of
the building or structure its improper use lack of maintenance frequent repairs and
alterations Also frequent restorations unnecessary uncovering and use of inappropriate
methods and materials can result in irreparable damage Substandard and inadequate
practices and professional qualifications have led to unfortunate results It is for this reason
that an appropriate document covering the principles of proper conservation-restoration of
wall paintings is necessary
The Venice Charter (1964) has provided general principles for the conservation-
restoration of cultural heritage The Amsterdam Declaration (1975) introducing the
concept of integrated conservation and the Nara Document on Authenticity (1994) dealing
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
35 Review of Literature
with cultural diversity have expanded these principles Taking into account these and
additional relevant contributions such as the ICOM-CC Code of Ethics (1984) Document
of Pavia (1997) and ECCO Professional Guidelines (1997) the aim of this document is
to provide more specific principles for the protection preservation and the conservation
restoration of wall paintings This document therefore reflects basic and universally
applicable principles and practices and does not take into account particular problems of
regions or countries which can be supplemented at regional and national level by
providing further recommendations where necessary
217 Preservation techniques of the mural paintings
The removal of fat salts varnishes and pollutants from the surfaces of the works
of art are mostly done by chemical and mechanical methods At the end of the 19th
century the practices of restoration methods that do not inhibit further future interventions
was considered acceptable During the 1960s several chemicals such as polymeric resins
were synthesized and applied as a consolidation or protection agents The accepted idea
was that these substances could be removed at any time leaving a completely unaltered
substrate On the basis of origin archaeological objects can be classified as follows
(Carretti 2005)
1 Inorganic It includes siliceous and nonsiliceous materials Archaeological materials
produced from stones terracotta ceramics and glass can be included under siliceous
materials whereas objects made of metals can be included under nonsiliceous inorganic
materials Again metal objects can be classified as ferrous metals and non-ferrous metals
Objects made of iron are termed as ferrous metal objects whereas metal objects made from
other than iron is termed as non-ferrous metal objects
2 Organic It includes archival and anthropological materials Again archival materials
include paper bhojapatra tadapatra textiles wooden objects miniature paintings whereas
anthropological objects include bone and ivory leather feather and fur etc
In the past restoration of paintings and other old artwork often involved application
of acrylic resins to consolidate and protect them One of the most important tasks for
modern restorers is thus to remove these layers because it turns out that acrylic resins not
only by drastically changing the optics of the treated artwork but in many cases they
accelerate their degradation The scientists use an oil-in-water microemulsion with the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
36 Review of Literature
organic solvent para-xylene as the oil component The matrix makes the cleaning agent
viscous so that it cannot enter very far into the pores of a painting (Carretti 2005)
Nanoparticle treatment is the logical evolution of the Ferroni-Dini method
Dispersions of kinetically stable Ca (OH)2 nanoparticles in non-aqueous solvents solved
most of the drawbacks of the microsized powders Stable dispersions of calcium hydroxide
have been successfully applied (replacing polymers) as fixatives to re-adhere lifted paint
layers during many restoration workshops in Italy and in Europe as a consolidant The
FerronindashDini method (two steps the application of a saturated solution of ammonium
carbonate (NH4)2CO3 and the treatment with a barium hydroxide solution Ba(OH)2 also
called the barium method has long been the acknowledged method for the removal of
salts that threaten paintings reinforcing at the same time the porous structure However
commercially available carbonates and hydroxide powders have dimensions of several
micrometres much larger than the pores on the paint surface This means they donrsquot
penetrate the painting well and there is also a risk of damaging the artwork by a white
glaze forming on the surface (Berger 2006) Restoration should provide the reinforcement
of the porous structure and the consolidation of the surface layer of arte facts A few
simple principles can be considered to define the most appropriate restoration method
1) The treatment should be reversible so that one can revert to the original status of the
work of art at any desired time
2) All the applied chemicals must ensure the maximum durability and the chemical
inertness
3) The applied chemicals must invert the degradation processes without altering the
chemical composition of the artefacts and their physico-chemical and mechanical
properties (Baglioni 2006)
218 Commercial preservative used for preservation of mural paintings
Cleaning was done using soft brushes vacuum cleaner and Gumma paine (dough)
a natural latex sponge Areas near the window were very dirty with black soot and were
cleaned with micro fibrous cloths moistened with synperonic N (surfactant alkyl phenol
ethoxylate based on nonyl phenol) and neutralized with clean water In several places the
paint layers had separated from the substrate (exfoli-ation) In that cases loose paint flakes
were stuck back using Paraloid B72 (10 solution in ethanol) as sparingly as possible
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
37 Review of Literature
Paraloid was injected with syringe behind the exfoliated area twice pushed and held back
with Melinex (polyester film) until fixed on the third application (Bionda et al 2002)
In a period of significant growth of molds and intensive efforts to stop the mold
contamination some of the lines of certain paintings were obscured or faded Solutions of
ethanol formalin 91 and Thiabendazole (TBZ) were used but they were not very
effective Para-formaldehyde fumigation was adopted beginning in 1981 to establish an
emergency treatment sensitivity of microorganisms from studied samples was tested
against Desogen by adding 1-3 (v v) in serial dilutions The best concentration
3 (vv) was applied with a brush to prevent spreading of the spores In order to overcome
the problem of fungal attack suitable fungicides carbendizeme or kiroxy-I or 5 solute of
N formaldehyde can be used Shellac solution in spirit or 2 solution of polyvinaycletate
in toluene can be used as preservative and consolidantsTo control insect and fungal attack
fumigants like pyrethrum DDT or 5 solution of sodium penta chlorophenate in kerosene
oil 2 to 5 solution of PVA in toluene or 2 to 5 solution of paraloid B-72 in toluene or
acetone be used (Miura 2009) Microclimatic conditions constitute a critical factor in the
conservation of cave paintings The unstable microclimatic condition is one of the factors
that always affect the state of conservation of mural paintings In the environmental-
monument system knowledge of the functional environment and climatic conditions of the
surroundings are necessary for the identification of causes of decay (Singh 2011)
Furthermore the risk of formation of indoor bioaerosols in residential and public
buildings (offices schools museums etc) has attracted interest in the last years due to
socio-economic as well as sanitary reasons (Ripka 2005) Thus it is important in aspects of
health and maintenance of Cultural Heritage to analyse the complete microflora to further
develop biocides for harmful microorganisms and methods for restoration of damaged
objects of art The biocidal testing was carried out on one representative algal species of
the two classes of algae viz Chlorococcum sp (green) and Chroococcus sp (blue-green)
found to be common in all the samples Efficiency tests were carried out both in liquid as
well as solid media containing algal suspensions by adding a biocide solution of known
concentration and determining the growth of the microorganism after the incubation
period The biocides used for the past studies were
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
22 Review of Literature
theses pigments may be used on leather or raw hide as well Early cave art in Seminole
Canyon was monochromatic in red and as culture grew more sophisticated the color
palette expanded Blue Orange Brown Green and Purple are the most common colours
used in Ajantha murals White Pink Gold are occasionally represented mineral earths
containing ferric oxide and copper carbonates were used as source of red yellow and green
colours There is also evidence to establish that root of Rubia cardifolia and leaves of
Indigofera tinctoria were used as source for red and blue colours (Nayer et al 1999)
Many colors of pigments were obtained from both organic and inorganic sources in
ancient times and used to paint various surfaces such as braintan leather clothing and
accoutrements rawhide the human body etc Blue color was obtained from powdered
azurite and lapis duck manure and certain clays Fine Blue-green clay was obtained from
deposits near Mankato Michigan Organic sources of blue include Turkeys Tail a
greenish blue polypore that grows on dead decaying wood (not tannish ones) Native
Americans get Indigo from either Guatemala or Ecuador which was traded well up onto
Kansas long before the Spanish ever set foot here American Indigo has purple tones to it
but IndianJapanese indigo has green tones Berries and crushed flowers were also used to
obtain blue color by rubbing the plant material directly on the leather
An organic source of red was Cochineal It was native west of the Mississippi and
is produced from the bodies of small insects that grow on the prickly pear cactus Ladys
Bedstraw gives a good vermillion red color Harvest the roots dry them out clean the mud
etc off of them and then grind the roots really fine then soak them to extract the red
coloring The key here is drying the root first Blood was also used as red pigment Pucoon
roots also yield a red pigment (Smith 2002) Red ochre the reverse original red colours are
due to variations in iron oxide (or) calcite content and to redox conditions in the firing
produced Brown coloured ceramics owe their colour to maghemite and must be
considered as a fabrication defect due to the position of the ceramic piece in a zone where a
reducing atmosphere prevailed in the course of firingRed pigments were produced from
iron oxides like hematite or limonite and from ochre Hematite was the most frequently
used mineral It occurs in the form of aggregates of small red crystals or in the form of
bigger black crystals which are difficult to crush white was obtained mostly from
kaolinite or illite (Clottes et al 1990)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
23 Review of Literature
210 Biodetoriation of mural paintings
Historic items often contain natural biodegradable materials and have histories of
exposure to moist conditions These two conditions make them amenable to microbial
attack Microbial colonization may damage the building or the cultural asset
(Salonen 2001) Biodeteriogens are organisms involved in deterioration of artifacts They
are very specific for each type of artifact in accordance with its chemical structure and
environment They also have different nutritional requirements and act directly or
indirectly on the substrate The adhesion of microorganisms to a substrate is the result of
cell hydrophobicity and of excreted polymeric substances contained by sheaths capsules
and slimes (Colao 2005)
The surviving wall paintings and decorations in subterranean environments around
Malta are rather scarce (Buhagiar 1986 1993 1998) These include those at St Paulrsquos
Catacombs (Zammit 2008) St Agatharsquos Crypt and Catacombs (Camilleri 2001)
San Catald Catacombs Tac-Cghaqi Abbatija tad-Dejr (Buhagiar 1993) all in Rabat the
cave-sanctuary in Mellieħa (Buhagiar 1987) and the Ħal Saflieni Hypogeum in Paola
(Pace 2000) Previous studies conducted on wall paintings and decorations in Maltese
Palaeo-Christian Catacombs have involved their manufacturing techniques (Muscat 2005)
However to date limited systematic studies have been conducted into the biodeterioration
in Maltese Palaeo- Christian Catacombs The only such studies ever conducted in Malta
concerned the biodeterioration of works of art in catacombs have been carried out at St
Agatharsquos Crypt and Catacombs in Rabat (Zammit et al 2008 Psaila 2006)
Microorganisms can be responsible for the destruction of monuments buildings
and cultural heritage assets including the decay of concrete cement stones mural
paintings etc These microorganisms are not only related with biodeterioration but water-
damaged indoor building materials are frequently colonized by complex bacterial
communities and may emit mixed bioaerosols into the indoor air (Jimenez 2000) It is
well known that mural paintings are colonized by micro-organisms and can be severely
damaged by such growths (Ciferri 1999) A large number of fungal (gt50) and bacterial
taxa (70) have been detected in indoor environments Over 50 bacterial species and 14
genera novel to science were reported in the past 10 years from indoor air and historic
items indicating bacterigravea in these enviroments are as yet only fragmentarily known
(Salonen 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
24 Review of Literature
Traditionally the study of microflora which causes this biodeterioration was based
on classical cultivation methods that were mainly useful to study the physiological
potential of microorganisms but do not provide information on all microbial communities
to be found in excavated artifacts Indeed many studies using culture-independent
techniques which cultivate microorganisms from different environments may often
represent only minor components of the microbial community as a whole It is generally
accepted that cultivation methods recover less than 1 of the total microorganisms present
in environmental samples (Ward et al 1990 Amann et al 1995) Hence microbial
investigations based only on cultivation strategies cannot be regarded as reliable in terms
of reflecting the microbial diversity present in objects of art (Osburn et al 2011)
Early workers suggested that the presence of living microorganisms on stone
increased its susceptibility to damage through their water-binding capacity It has recently
been reported that the mineralogy porosity surface roughness and capacity to collect
water and organic materials control its bioreceptivity and tendency to biodeterioration
(Diakumaku 1995) In addition environmental factors as temperature light pH and
relative humidity affect the number and type of colonising species (Tiano et al 1995) and
hence the progress of colonisation Biofilms on decayed stones consist on mixed microbial
populations embedded in a polymeric matrix Fungi algae filamentous and unicellular
bacteria are found in these complex communities A variety of bacteria have been isolated
from different stone samples confirming the dominance of Gram-positive organisms
especially spore-forming bacteria such as Bacillus and filamentous actinomycetes
(Ripka 2005)
In cultivation studies of deteriorated mural and rock paintings bacterial isolates
have frequently been attributed to the genus Bacillus (Weirich 1989 Tate and Rebrikova
1991 Gonzalez et al 1999 Heyrman et al 1999 Jimenez et al 2000) Other studies that
have included DNA-based techniques to characterize the bacterial community involved in
biodeterioration have shown that a substantial part of the bacterial population is made up of
so far unknown species (Altenburger et al 1996 Rolleke et al 1996 Gurtner et al 2000
Heyrman and Swings 2001) (Heymann et al 2003)
Many potential mycotoxin producers have been detected in air and items from
indoor environments with histories of exposure to moisture for example species of
Acremonium Alternaria Aspergillus Chateomium Fusarium Eurotium Paecilomyces
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
25 Review of Literature
Penicillium Scopulariopsis Stachybotrys Trichoderma Verticillium and Wallemia
(Peltola et al 2001 Pieckova et al 2001) Not all strains of one species produce
mycotoxins and different strains may produce different toxins Whereas toxin producing
strains are frequent in crops and outdoor vegetation toxin producing isolates from indoor
environments and non living assets have only been reported of the species Aspergillus
versicolor (Nielsen et al 1998) Stachybotrys chartarum Nikulin (1997) and
Trichoderma harzianum (Peltola et al 2001) Streptomyces griseus strains producing
valinomycin occur in environments where humans can get exposed
(Andersson et al 2002) The biological properties and toxicity mechanisms of cereulide
were identical to those by valinomycin (Mikkola et al 1999 Salonen et al 2001)
The genus Paenibacillus was first proposed by Ash et al (1993) and its description
was emended by Shida et al (1997) The genus Paenibacillus is under intensive taxonomic
investigation with ten species having been formally described in the last year Heyrman amp
Swings (2001) isolated a strain originally classified as Paenibacillus sp LMG 19508
from biodeteriorated mural paintings in the Servilia tomb at the Roman necropolis of
Carmona in Seville Spain (Smerda et al 2006) Building stone and wall paintings contain
a variety of hydroscopic salts including carbonates chlorides nitrates sulfates etc
dispersed within the porous material or locally concentrated These salts are solubilised
and migrate with the water in and out of the stone Due to changes in physical parameters
the so called salt efflorescences appear on the surfaces providing extremely saline
environments and building niches for settlement of halophilic microorganisms Halite and
other hygroscopic salts can retain considerable quantities of moisture when entrapped in
the building materials and thus favouring the bacterial growth (Ripka 2005)
It is demonstrated that water-damaged indoor building materials contained
substances of microbial origin extremely toxic to eukaryotic cells and large quantities of
several microbial species known to be potentially toxic or immunopotentiating These
include peptidoglycans Gram-negative endotoxin β-13-D glucans lipoglycans and
teichoic acids and mycotoxins (Jimenez 2000) In turn these microorganisms can mediate
the crystallization process These crystallizations can produce destructive effects Some
salts may crystallize or recrystallize to different hydrates which occupy a larger space and
exert additional pressure producing cracking powdering and flaking
(Jimenez and Laiz 2000)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
26 Review of Literature
211 Types of deterioration on mural paintings
The frescos represent a variety of ecological niches where primary colonization is
due to photoautotrophic and chemolithoautotrophic microorganisms followed by
secondary colonization due to heterotrophic bacteria that obtain nutrients from various
sources (metabolites of autotrophic bacteria airborne organic contamination animal faeces
and organic compounds in the paint layers themselves) Microbial-induced deterioration
processes cause structural as well as aesthetic damage to wall paintings such as the
discoloration of materials the formation of crusts on surfaces and the loss of material
(Sarro et al 2006 Osburn et al 2011) Halophilic bacteria and archaea were thought to
be found only in extreme environments like salt lakes or black smokers However it has
been shown that mural paintings and stones are a common habitat for extremely salt
tolerant and moderate halophilic (Ripka 2005) Microbial induced deterioration processes
can cause different kinds of alterations such as discolouration of materials the formation of
crusts on surfaces and the loss of material which leads to structural damage (Ripka 2005)
First of all microorganisms can cause severe problems due to the excretion of aggressive
metabolic products such as organic or inorganic acids Secondly material components can
be used as substrates for microbial metabolism Exoenzymes such as cellulases proteases
tannases beta-glucosidase produced by fungi and bacteria are responsible for hydrolysis of
cellulose and proteins Further examples are mechanical processes caused by swelling and
shrinking of slime or mycelia penetrating inside plaster of the painting resulting in loss of
cohesion and detachment of the paint layer (Rolleke 1996 Gurtner et al 2000)
Table-21 Microbial damage on mural paintings (Rolleke 1996)
S No Damage Microbial activity
1 Green brown red grey
surface layers (patinas)
Pigments produced by microorganisms (intra-or
extracellular) as chlorophyll and carotinoids
2 Dislodging of painting layers Use of organic binders as nutrient and energy
source
3 Acid attack of carbonates Acid produced by fungi or bacteria
4 Discolouration of pigments Redox-reactions induced by fungi and
bacteria
5 Loss of paint layer Growth of microorganisms deep into the plaster
6 Hydrolysis of synthetic
polymers Chemoorganotrophic activity of bacteria and fungi
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
27 Review of Literature
Discolorations are caused by excretion of pigments and microbiologically induced
reductionoxidation-processes (Krumbein et al 1990) Degradation of the bindings is
followed by reduction of stability Oxidation of ammonium and reduced sulphur
compounds results in acidification of the environment such as Sulphuric acid and the
variety of organic acids produced by the heterotrophs cause solubilization of calcareous
binding material and chelation of metal ions (Bock et al 1993) It is now well recognised
that wall paintings can be deteriorated by microorganisms (Ciferri 1999)The growth of
microorganisms essentially results in two types of damage aesthetic and structural
Aesthetic damage implies pigment discoloration stains and formation of a biofilm on the
painted surface Structural damage is observed as cracking and disintegration of the paint
layer formation of paint blisters and degradation of support polymers or of glues and
binders resulting in detachment of paint layer from the support The colonization of mural
paintings by bacteria and other microorganisms can have different causes Provided that
favorable environmental conditions occur nutrients for heterotrophic bacteria and fungi
can be available from metabolites of autotrophic bacteria from airborne contamination and
dripping water from animal faeces but also from organic compounds in the paint layer
itself
212 Methods of studying biodeterioration
It is now well recognized that wall paintings may be deteriorated by
microorganisms as established by several studies that linked the observed damage with the
microbial community present as reviewed by Ciferri (1999) Despite this knowledge a
reliable characterization of bacteria associated with such damage is often lacking To
obtain greater insight into the bacterial community involved in biodeterioration of mural
paintings three sites (from the necropolis at Carmona Spain and the Saint-Catherine
chapel of the castle at Herberstein Austria) were sampled In previous studies from these
sites 385 isolates were analysed by fatty acid methyl ester GC and representatives of
different fatty acid clusters were further studied by 16S rRNA gene sequencing
(Heyrman and Swings 2001) Several of these representative strains showed the highest
sequence similarity with members of the genus Arthrobacter (Heyrman et al 2005)
Jimenez and Samson (1981) analysed the microbial flora of a large fresco painted
in the late 1920s in the monastery ldquoSanta Maria de la Rabidardquo (Huelva Spain) exhibiting
two types of deterioration white efflorescence and green-to-black stains
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
28 Review of Literature
Tate and Rebrikova (1990) thought autotrophic nitrifying bacteria to be the first colonisers
of damaged frescoes and building materials in the cathedral of the nativity of the Virgin in
the Pafnutii-Borovskii monastery (Russia) The bulk of research on biodeterioration of
mural paintings has focused on explaining the observed phenomena by analysing the
microflora present Following this approach a precise characterisation of the
microorganisms using a polyphasic approach was never the first goal
Only a few studies included genomic fingerprinting (16S rDNA sequence analysis)
for the characterisation of bacteria associated with damage on mural paintings
[Rolleke (1996) Pinar et al (2001)] Previous studies based on culture-dependent
techniques showed that the flora present on frescos are fungi (predominant species of
Penicillium Aspergillus Cladosporium and Engyodontium) (Guglielminetti et al 1994)
bacteria (predominant species of Bacillus Arthrobacter Micrococcus Streptomyces and
Pseudomonas) (Heyrman et al 1999) cyanobacteria and eukaryotic algae (species of
Nostoc Lyngbya and Chlorophyceae) (Arino et al 1996 Calvo et al 1993) The killing
effect of an antimicrobial agent on a microorganism can be assessed in several ways
(1) Lethal activity may be expressed as the rate of killing by a fixed concentration
of drug under controlled conditions This rate is determined by measuring the number of
viable bacteria at various time intervals The resulting graphic depiction is known as the
time-kill curve Bacterial killing rates are in part dependent on the class of antibiotic and
the concentration of this agent With certain classes of antibiotics (eg aminoglycosides
and fluoroquino-lones) the rate of killing increases with increased drug concentrations up
to a point of maximum effect This is termed concentration-dependent bactericidal activity
In contrast the killing rates of szlig-lactam agents and vancomycin are relatively slow and
continue only as long as the concentrations are in excess of the MIC This rate of killing is
termed time-dependent bactericidal activity
(2) The minimal concentration of drug needed to kill most of the viable organisms
after incubation for a fixed length of time (generally 24 hours) under a given set of
conditions is the most common estimation of bactericidal activity and is known as either
the minimal bactericidal concentration (MBC) or the minimal lethal concentration (MLC)
It will be referred to in this document as the MBC Unfortunately the definition of the
MBC (999 killing of the final inoculum) is somewhat arbitrary and separates the
bacteria into two populations ndash a segrega-tion which might not have biological relevance
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
29 Review of Literature
The determination of the MBC moreover is so subject to methodologic variables that the
clinical relevance of MBCs is nearly impossible to assess particularly for certain pathogen
and drug combinations (eg Staphylococci and beta-lactam agents)
(3) The serum of a patient receiving an antibiotic may be tested against the
infecting microorganism This can be done using time-kill curve methodology (ie serum
bactericidal rate) or using dilution methodology (ie serum bactericidal titer) The
principles of these methods as well as the influence of biological and technical factors are
similar (Barry et al 1999)
213 Microbial flora associated with deteriorated mural paintings
A great deal of research has been done in this field mainly by using cultivation dependent
methods However by using culture-dependent methods only a very small proportion of
microorganisms can be obtained Far less than 1 of organisms in the environment can be
cultivated by standard cultivation techniques (Pace 1996) Recent studies have shown that
culture-dependent techniques yielded mainly sporeforming bacteria suggesting that plating
leads to an over estimation of the number of spore-forming bacteria A wide number of
investigations have shown that in addition to chemical and physical processes
microorganisms play a major role in degradation of objects of art such as paintings stone-
works wood paper masonry leather parchment glass and metal (Ripka 2005)
A) Bacteria
In general growth of diverse organisms on mural paintings is supported by
humidity slight alkaline pH values and the presence of organic and inorganic nutrient
sources (Weirich 1989) In mural paintings pigments are suspended in water or oil often
binders such as casein and milk are used and they are supplied on the damp lime plaster
(Ciferri 1999) The calcium carbonate formed on contact with air consolidates the
pigments Thus frescos contain mainly inorganic components While chemoautotrophic
nitrifiers and thiobacilli obtain their energy for growth by oxidizing ammonium and
reducing sulphur-compounds respectively heterotrophic bacteria and fungi depend on
organically bound carbon [Tate et al (1991) Lazar (1971) Petushkova et al (1986)
Jimenez et al (1981)] Thus primary colonization of photoautotrophic Cyanobacteria
chemolithoautotrophic nitrifying bacteria and sulphuric acid producing thiobacilli represent
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
30 Review of Literature
the first supply of organic matter The death and lysis of such bacteria promotes the
secondary settlement of heterotrophic bacteria and fungal populations (Calvo et al 1991)
Bacteria may derive from plants or pollen as many sequences obtained in this study
gave high score similarities with bacteria isolated from plants like Moraxella osloensis
Enterobacter cloace Enterobacter agglomerans and Pantoea endophytica Bacteria may
also derive from animal faeces like flies Bacillus Pseudomonas Aeromonas and Panteoa
(Ripka 2005) As Lazar and Dumitru (1973) reported studying mural paintings in a
Romanian monastery the genera Bacillus Arthrobacter and Pseudomonas have been
proved to produce salt efflorescences and were even considered to cause the blanching
phenomenon of frescoes (Jimenez et al 2000) Predominant bacterial genera are Bacillus
Streptomyces Arthrobacter Micrococcus and Pseudomonas [Weirich (1989)
Tate et al (1990) Arroyo et al (1997) Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
B) Fungi
It may be concluded that there is wide variety of fungal forms present on mural
paintings but Aspergillus and Alternaria were found dominating from all the experimental
sites next to them were Cladosporium Drechestera Fusarium Curvularia Chaetomium
Memnoniella Mycelia sterelai Pencillium Emericella Stachybotrytis Trichoderma
Phoma Monodictys Humicola and Epicoccum (Garg et al 1995)
The fungal genera most commonly found in lists of isolated taxa given in literature
are Alternaria Aspergillus Chaetomium Cladosporium Fusarium Penicillium and
Verticullum [Weirich (1989) Tate et al (1990) Guglielminetti et al (1994)
Garg et al (1995) Berner et al (1997) Ciferri (1999)] Some fungi having hard fruiting
bodies represented by sclerotia pycnidia perithecia cleistothecia and stroma could
organize themselves inside the painted layer Many fungal forms having such structures
were identified from our experimental sites viz Emericella nidulans A flavus
Chaetomium sp and Phoma sp etc These structures with little increase in humidity may
cause swelling in the paint film (Garg 1995)
Strains of species of Alternaria and Cladosporium both of them identified on the
mural paintings of the Palace of Schoumlnbrunn are the most common genera isolated from
stone and mural paintings in indoor environments with standard cultivation methods
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
31 Review of Literature
(Ventosa 2004) Saprophytic species of the genus Cladosporium are among the most
abundant fungi isolated in saltern samples Commonly isolated Cyanobacteria belong to
Nostoc and eukaryotic algae to Lyngbya and members of the Chlorophyceae such as
Chlorella Pseudococcomyxa and Pseudopleurococcus [Gorbushina et al (1987)
Calvo et al (1993) Arino et al (1996)]
They grow optimally on media with low water activity due to high salt or sugar
concentrations seem to propagate 70 vegetatively in the salterns and are thus
halotolerantosmotolerant species rather than simple flush-through occurrences
Cladiosporum herbarum was frequently isolated from hypersaline waters dead and dying
plant material air soil food fruit cereals paint and textiles (Ventosa 2004)
C) Algae
Most of the painted areas in temperature climate became covered with green algae
(Pleurococcus Protococcus and Trentopholia) while under tropical conditions blue green
algae of the genera Oscillatoria and Sytonema predominated (Garg 1995) The main
factors which contribute to the growth of algae on wall paintings are the presence of
moisture in the plaster as well as availability of visible light These conditions are quite
prevalent in the tropical climate but in temperature regions also algal growth on wall
paintings have been reported [Tonolo et al (1961) Pietrini et al (1991)]
D) Actinomycetes
Usually literature refers to specific aspects eg the occurrence of cyanobacteria
and algae in caves with natural openings to sunlight or those with artificial lighting fungi
and so forth Actinomycetes have been considered to be mainly confined to soils where
they find their natural habitat but despite intensive studies there are still many gaps in our
knowledge of the role played by actinomycetes in soil processes and biodegrations of
murals cave paintings (Groth et al 1999) In addition halophilic bacteria actinomycetes
and cyanobacteria are also capable of growing on salt-affected mural paintings
(Karbowska 2003)
Monte and Ferrari (1993) reviewed the mechanisms of biodeterioration in tombs
and underground churches The role of actinomycetes in the deterioration of frescoes in
hypogean environments was stressed by Agarossi et al (1985) Monte and Ferrari (1993)
Giacobini et al (1987) described the serious damage suffered by a whole series of famous
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
32 Review of Literature
frescoes in underground environments Actinomycetes were isolated from these mural
paintings located in crypts caves and tombs About 200 strains of actinomycetes were
isolated 60 of which were identified The most frequent species were Streptomyces albus
S cinereoruber S griseolus S vinaceus and some members of the Nocardia genus
Heterotrophic bacteria and actinomycetes were the most abundant microorganisms
on the frescoes of Etruscan tombs (Agarossi et al 1985) Bettini et al (1977) studied
some of the oldest Etruscan tombs (7th to 4th century BC) and found white-grey patinas
and spots from streptomycetes in the mural paintings They related the biodeterioration to
the microclimatic conditions (eg lower temperatures high RH) Monte and Ferrari (1993)
considered that colonization of the mural paintings was the result of selective competitive
and inhibitory dynamics among different microorganisms under different and changing
environmental conditions The pigments excreted by some actinomycetes were responsible
for the violet stains found on the walls of tombs in Tarquinia Similar stains were observed
in one of the Roman tombs the Circular Mausoleum the Necropolis of Carmona Spain
from which a Streptomyces sp producing violet pigments in culture media was isolated
214 Identification of biodeteriogens
The possibility of pigments and biodeteriogens identification in frescos and stone
monitoring is offered mostly by vibrational spectroscopy infrared thermography laser
induced fluorescence (LIF) laser induced breakdown spectroscopy (LIBS) XRF (X-Ray
Fluorescence) IR and UV emission Among them laser based methods allowing for in
situ or remote characterization of artwork surface were applied successfully for
prospecting diagnosis and maintenance (Colao et al 2005) The rep-PCR fingerprinting
of the isolates allowed determination of their genotypic diversity Studies that have
compared rep-PCR genomic fingerprint analysis with DNAndashDNA relatedness studies have
shown that the two techniques yield results that are in close agreement [Nick et al (1999)
Rademaker et al (2000)] These studies therefore suggest that rep-PCR fingerprinting can
be used as a genomic screening method to differentiate at the species level and to select
representatives for DNAndashDNA reassociation experiments (Heymann et al 2003)
The characterisation of bacteria was for example often limited to isolation from
group-specific media followed by microscopy [Sorlini et al (1987) Weirich (1989)
Tate et al (1990) and in more recent studies to morphological and physiological
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
33 Review of Literature
characteristics including miniaturised and automated systems such as API and BIOLOG
[Arroyo et al (1997) Jimmenez et al (2000) and Laiz et al (2000)] or to
chemotaxonomic characteristics [Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
Wagner et al (1994) demonstrated that conventional microbiological efforts can
fail to isolate all microorganisms present in natural samples DNA-based techniques used
to identify microorganisms have revealed only a smaller fraction of bacteria isolated from
artworks (Ward et al 1990 Rolleke et al 1996) Bacterial identification using molecular
techniques especially those including the sequencing of genes coding for ribosomal
16S rRNA is very important to study bacterial communities found on artefacts One such
method is Denaturing Gradient Gel Electrophoresis (DGGE) of PCR-amplified gene
fragments coding for rRNA (Muyzer et al 1993) that allows the separation of partial
16S rDNA amplified fragments of identical length but different sequence due to their
different melting behaviour in a gel system containing a gradient of denaturants
(Jimenez 2003)
Total genomic DNA was purified for 16S rRNA gene sequencing and rep-PCR
using a slight modification of the method of Pitcher et al (1989) as described by
Heyndrickx et al (1996) rep-PCR genomic fingerprinting was performed with the REP-
and (GTG)5 primers (Versalovic et al 1994) using the PCR conditions described
previously by Rademaker et al (1997) Electrophoresis and pattern analysis were further
performed as described by Heyrman et al (2003) 16S rRNA gene sequencing and
phylogenetic analysis were performed as described by Heyrman and Swings (2001)
Phylogenetic trees were constructed using the BioNumerics software (Applied Maths) by
applying the neighbour-joining and maximum-parsimony methods on a multiple alignment
similarity matrix The stability of relationships was assessed by a bootstrap analysis of
1000 datasets For determination of the G+C content and levels of DNAndashDNA
hybridization approximately 1 g biomass was harvested from agar plates DNA was
purified by using a combination of the protocols of Marmur (1961) and
Pitcher et al (1989) as described by Logan et al (2000) The G+C content of the DNA
was determined by HPLC (Mesbah et al 1989) using the further specifications given by
Logan et al (2000) DNAndashDNA hybridization experiments were performed using a
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
34 Review of Literature
modification of the microplate method of Ezaki et al (1989) as described by
Willems et al (2001)
215 Preservation and conservation
Nowadays the conservation and preservation of our cultural heritage is one of the
world main concerns particularly in Europe The increasing need for non-destructive
investigation tools has become a major issue as sampling is in most cases restricted in
view of the value or the uniqueness of the object Artworks as wall paintings in buildings
and monuments of historical interest are affected by environment physical (temperature
and humidity) and biological factors (biodeteriogens) and by human (pollutant releases)
impact and therefore modified over the time The term ldquoconservationrdquo may have many
different meanings in different fields Every intervention directed to the restoration and
safeguard of works of art is commonly considered as a conservation treatment For
example conservation can involve the cleaning procedures set up by chemists or the photo
documentation of the preservation of historical memory For the appropriate conservation
of works of art even the lighting systems in a museum or the control of the visitorrsquos
movements in a site should be monitored Chemical degradation which induces the flaking
of paintings and deterioration from rain wind dust and other environmental causes is
mainly responsible for the weakening of the porous structure and the surface layers of the
materials used in works of cultural heritage (Colao et al 2005)
216 Conservation history
Wall paintings are an integral part of monuments and sites and should be preserved
in situ Many of the problems affecting wall paintings are linked to the poor condition of
the building or structure its improper use lack of maintenance frequent repairs and
alterations Also frequent restorations unnecessary uncovering and use of inappropriate
methods and materials can result in irreparable damage Substandard and inadequate
practices and professional qualifications have led to unfortunate results It is for this reason
that an appropriate document covering the principles of proper conservation-restoration of
wall paintings is necessary
The Venice Charter (1964) has provided general principles for the conservation-
restoration of cultural heritage The Amsterdam Declaration (1975) introducing the
concept of integrated conservation and the Nara Document on Authenticity (1994) dealing
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
35 Review of Literature
with cultural diversity have expanded these principles Taking into account these and
additional relevant contributions such as the ICOM-CC Code of Ethics (1984) Document
of Pavia (1997) and ECCO Professional Guidelines (1997) the aim of this document is
to provide more specific principles for the protection preservation and the conservation
restoration of wall paintings This document therefore reflects basic and universally
applicable principles and practices and does not take into account particular problems of
regions or countries which can be supplemented at regional and national level by
providing further recommendations where necessary
217 Preservation techniques of the mural paintings
The removal of fat salts varnishes and pollutants from the surfaces of the works
of art are mostly done by chemical and mechanical methods At the end of the 19th
century the practices of restoration methods that do not inhibit further future interventions
was considered acceptable During the 1960s several chemicals such as polymeric resins
were synthesized and applied as a consolidation or protection agents The accepted idea
was that these substances could be removed at any time leaving a completely unaltered
substrate On the basis of origin archaeological objects can be classified as follows
(Carretti 2005)
1 Inorganic It includes siliceous and nonsiliceous materials Archaeological materials
produced from stones terracotta ceramics and glass can be included under siliceous
materials whereas objects made of metals can be included under nonsiliceous inorganic
materials Again metal objects can be classified as ferrous metals and non-ferrous metals
Objects made of iron are termed as ferrous metal objects whereas metal objects made from
other than iron is termed as non-ferrous metal objects
2 Organic It includes archival and anthropological materials Again archival materials
include paper bhojapatra tadapatra textiles wooden objects miniature paintings whereas
anthropological objects include bone and ivory leather feather and fur etc
In the past restoration of paintings and other old artwork often involved application
of acrylic resins to consolidate and protect them One of the most important tasks for
modern restorers is thus to remove these layers because it turns out that acrylic resins not
only by drastically changing the optics of the treated artwork but in many cases they
accelerate their degradation The scientists use an oil-in-water microemulsion with the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
36 Review of Literature
organic solvent para-xylene as the oil component The matrix makes the cleaning agent
viscous so that it cannot enter very far into the pores of a painting (Carretti 2005)
Nanoparticle treatment is the logical evolution of the Ferroni-Dini method
Dispersions of kinetically stable Ca (OH)2 nanoparticles in non-aqueous solvents solved
most of the drawbacks of the microsized powders Stable dispersions of calcium hydroxide
have been successfully applied (replacing polymers) as fixatives to re-adhere lifted paint
layers during many restoration workshops in Italy and in Europe as a consolidant The
FerronindashDini method (two steps the application of a saturated solution of ammonium
carbonate (NH4)2CO3 and the treatment with a barium hydroxide solution Ba(OH)2 also
called the barium method has long been the acknowledged method for the removal of
salts that threaten paintings reinforcing at the same time the porous structure However
commercially available carbonates and hydroxide powders have dimensions of several
micrometres much larger than the pores on the paint surface This means they donrsquot
penetrate the painting well and there is also a risk of damaging the artwork by a white
glaze forming on the surface (Berger 2006) Restoration should provide the reinforcement
of the porous structure and the consolidation of the surface layer of arte facts A few
simple principles can be considered to define the most appropriate restoration method
1) The treatment should be reversible so that one can revert to the original status of the
work of art at any desired time
2) All the applied chemicals must ensure the maximum durability and the chemical
inertness
3) The applied chemicals must invert the degradation processes without altering the
chemical composition of the artefacts and their physico-chemical and mechanical
properties (Baglioni 2006)
218 Commercial preservative used for preservation of mural paintings
Cleaning was done using soft brushes vacuum cleaner and Gumma paine (dough)
a natural latex sponge Areas near the window were very dirty with black soot and were
cleaned with micro fibrous cloths moistened with synperonic N (surfactant alkyl phenol
ethoxylate based on nonyl phenol) and neutralized with clean water In several places the
paint layers had separated from the substrate (exfoli-ation) In that cases loose paint flakes
were stuck back using Paraloid B72 (10 solution in ethanol) as sparingly as possible
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
37 Review of Literature
Paraloid was injected with syringe behind the exfoliated area twice pushed and held back
with Melinex (polyester film) until fixed on the third application (Bionda et al 2002)
In a period of significant growth of molds and intensive efforts to stop the mold
contamination some of the lines of certain paintings were obscured or faded Solutions of
ethanol formalin 91 and Thiabendazole (TBZ) were used but they were not very
effective Para-formaldehyde fumigation was adopted beginning in 1981 to establish an
emergency treatment sensitivity of microorganisms from studied samples was tested
against Desogen by adding 1-3 (v v) in serial dilutions The best concentration
3 (vv) was applied with a brush to prevent spreading of the spores In order to overcome
the problem of fungal attack suitable fungicides carbendizeme or kiroxy-I or 5 solute of
N formaldehyde can be used Shellac solution in spirit or 2 solution of polyvinaycletate
in toluene can be used as preservative and consolidantsTo control insect and fungal attack
fumigants like pyrethrum DDT or 5 solution of sodium penta chlorophenate in kerosene
oil 2 to 5 solution of PVA in toluene or 2 to 5 solution of paraloid B-72 in toluene or
acetone be used (Miura 2009) Microclimatic conditions constitute a critical factor in the
conservation of cave paintings The unstable microclimatic condition is one of the factors
that always affect the state of conservation of mural paintings In the environmental-
monument system knowledge of the functional environment and climatic conditions of the
surroundings are necessary for the identification of causes of decay (Singh 2011)
Furthermore the risk of formation of indoor bioaerosols in residential and public
buildings (offices schools museums etc) has attracted interest in the last years due to
socio-economic as well as sanitary reasons (Ripka 2005) Thus it is important in aspects of
health and maintenance of Cultural Heritage to analyse the complete microflora to further
develop biocides for harmful microorganisms and methods for restoration of damaged
objects of art The biocidal testing was carried out on one representative algal species of
the two classes of algae viz Chlorococcum sp (green) and Chroococcus sp (blue-green)
found to be common in all the samples Efficiency tests were carried out both in liquid as
well as solid media containing algal suspensions by adding a biocide solution of known
concentration and determining the growth of the microorganism after the incubation
period The biocides used for the past studies were
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
23 Review of Literature
210 Biodetoriation of mural paintings
Historic items often contain natural biodegradable materials and have histories of
exposure to moist conditions These two conditions make them amenable to microbial
attack Microbial colonization may damage the building or the cultural asset
(Salonen 2001) Biodeteriogens are organisms involved in deterioration of artifacts They
are very specific for each type of artifact in accordance with its chemical structure and
environment They also have different nutritional requirements and act directly or
indirectly on the substrate The adhesion of microorganisms to a substrate is the result of
cell hydrophobicity and of excreted polymeric substances contained by sheaths capsules
and slimes (Colao 2005)
The surviving wall paintings and decorations in subterranean environments around
Malta are rather scarce (Buhagiar 1986 1993 1998) These include those at St Paulrsquos
Catacombs (Zammit 2008) St Agatharsquos Crypt and Catacombs (Camilleri 2001)
San Catald Catacombs Tac-Cghaqi Abbatija tad-Dejr (Buhagiar 1993) all in Rabat the
cave-sanctuary in Mellieħa (Buhagiar 1987) and the Ħal Saflieni Hypogeum in Paola
(Pace 2000) Previous studies conducted on wall paintings and decorations in Maltese
Palaeo-Christian Catacombs have involved their manufacturing techniques (Muscat 2005)
However to date limited systematic studies have been conducted into the biodeterioration
in Maltese Palaeo- Christian Catacombs The only such studies ever conducted in Malta
concerned the biodeterioration of works of art in catacombs have been carried out at St
Agatharsquos Crypt and Catacombs in Rabat (Zammit et al 2008 Psaila 2006)
Microorganisms can be responsible for the destruction of monuments buildings
and cultural heritage assets including the decay of concrete cement stones mural
paintings etc These microorganisms are not only related with biodeterioration but water-
damaged indoor building materials are frequently colonized by complex bacterial
communities and may emit mixed bioaerosols into the indoor air (Jimenez 2000) It is
well known that mural paintings are colonized by micro-organisms and can be severely
damaged by such growths (Ciferri 1999) A large number of fungal (gt50) and bacterial
taxa (70) have been detected in indoor environments Over 50 bacterial species and 14
genera novel to science were reported in the past 10 years from indoor air and historic
items indicating bacterigravea in these enviroments are as yet only fragmentarily known
(Salonen 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
24 Review of Literature
Traditionally the study of microflora which causes this biodeterioration was based
on classical cultivation methods that were mainly useful to study the physiological
potential of microorganisms but do not provide information on all microbial communities
to be found in excavated artifacts Indeed many studies using culture-independent
techniques which cultivate microorganisms from different environments may often
represent only minor components of the microbial community as a whole It is generally
accepted that cultivation methods recover less than 1 of the total microorganisms present
in environmental samples (Ward et al 1990 Amann et al 1995) Hence microbial
investigations based only on cultivation strategies cannot be regarded as reliable in terms
of reflecting the microbial diversity present in objects of art (Osburn et al 2011)
Early workers suggested that the presence of living microorganisms on stone
increased its susceptibility to damage through their water-binding capacity It has recently
been reported that the mineralogy porosity surface roughness and capacity to collect
water and organic materials control its bioreceptivity and tendency to biodeterioration
(Diakumaku 1995) In addition environmental factors as temperature light pH and
relative humidity affect the number and type of colonising species (Tiano et al 1995) and
hence the progress of colonisation Biofilms on decayed stones consist on mixed microbial
populations embedded in a polymeric matrix Fungi algae filamentous and unicellular
bacteria are found in these complex communities A variety of bacteria have been isolated
from different stone samples confirming the dominance of Gram-positive organisms
especially spore-forming bacteria such as Bacillus and filamentous actinomycetes
(Ripka 2005)
In cultivation studies of deteriorated mural and rock paintings bacterial isolates
have frequently been attributed to the genus Bacillus (Weirich 1989 Tate and Rebrikova
1991 Gonzalez et al 1999 Heyrman et al 1999 Jimenez et al 2000) Other studies that
have included DNA-based techniques to characterize the bacterial community involved in
biodeterioration have shown that a substantial part of the bacterial population is made up of
so far unknown species (Altenburger et al 1996 Rolleke et al 1996 Gurtner et al 2000
Heyrman and Swings 2001) (Heymann et al 2003)
Many potential mycotoxin producers have been detected in air and items from
indoor environments with histories of exposure to moisture for example species of
Acremonium Alternaria Aspergillus Chateomium Fusarium Eurotium Paecilomyces
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
25 Review of Literature
Penicillium Scopulariopsis Stachybotrys Trichoderma Verticillium and Wallemia
(Peltola et al 2001 Pieckova et al 2001) Not all strains of one species produce
mycotoxins and different strains may produce different toxins Whereas toxin producing
strains are frequent in crops and outdoor vegetation toxin producing isolates from indoor
environments and non living assets have only been reported of the species Aspergillus
versicolor (Nielsen et al 1998) Stachybotrys chartarum Nikulin (1997) and
Trichoderma harzianum (Peltola et al 2001) Streptomyces griseus strains producing
valinomycin occur in environments where humans can get exposed
(Andersson et al 2002) The biological properties and toxicity mechanisms of cereulide
were identical to those by valinomycin (Mikkola et al 1999 Salonen et al 2001)
The genus Paenibacillus was first proposed by Ash et al (1993) and its description
was emended by Shida et al (1997) The genus Paenibacillus is under intensive taxonomic
investigation with ten species having been formally described in the last year Heyrman amp
Swings (2001) isolated a strain originally classified as Paenibacillus sp LMG 19508
from biodeteriorated mural paintings in the Servilia tomb at the Roman necropolis of
Carmona in Seville Spain (Smerda et al 2006) Building stone and wall paintings contain
a variety of hydroscopic salts including carbonates chlorides nitrates sulfates etc
dispersed within the porous material or locally concentrated These salts are solubilised
and migrate with the water in and out of the stone Due to changes in physical parameters
the so called salt efflorescences appear on the surfaces providing extremely saline
environments and building niches for settlement of halophilic microorganisms Halite and
other hygroscopic salts can retain considerable quantities of moisture when entrapped in
the building materials and thus favouring the bacterial growth (Ripka 2005)
It is demonstrated that water-damaged indoor building materials contained
substances of microbial origin extremely toxic to eukaryotic cells and large quantities of
several microbial species known to be potentially toxic or immunopotentiating These
include peptidoglycans Gram-negative endotoxin β-13-D glucans lipoglycans and
teichoic acids and mycotoxins (Jimenez 2000) In turn these microorganisms can mediate
the crystallization process These crystallizations can produce destructive effects Some
salts may crystallize or recrystallize to different hydrates which occupy a larger space and
exert additional pressure producing cracking powdering and flaking
(Jimenez and Laiz 2000)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
26 Review of Literature
211 Types of deterioration on mural paintings
The frescos represent a variety of ecological niches where primary colonization is
due to photoautotrophic and chemolithoautotrophic microorganisms followed by
secondary colonization due to heterotrophic bacteria that obtain nutrients from various
sources (metabolites of autotrophic bacteria airborne organic contamination animal faeces
and organic compounds in the paint layers themselves) Microbial-induced deterioration
processes cause structural as well as aesthetic damage to wall paintings such as the
discoloration of materials the formation of crusts on surfaces and the loss of material
(Sarro et al 2006 Osburn et al 2011) Halophilic bacteria and archaea were thought to
be found only in extreme environments like salt lakes or black smokers However it has
been shown that mural paintings and stones are a common habitat for extremely salt
tolerant and moderate halophilic (Ripka 2005) Microbial induced deterioration processes
can cause different kinds of alterations such as discolouration of materials the formation of
crusts on surfaces and the loss of material which leads to structural damage (Ripka 2005)
First of all microorganisms can cause severe problems due to the excretion of aggressive
metabolic products such as organic or inorganic acids Secondly material components can
be used as substrates for microbial metabolism Exoenzymes such as cellulases proteases
tannases beta-glucosidase produced by fungi and bacteria are responsible for hydrolysis of
cellulose and proteins Further examples are mechanical processes caused by swelling and
shrinking of slime or mycelia penetrating inside plaster of the painting resulting in loss of
cohesion and detachment of the paint layer (Rolleke 1996 Gurtner et al 2000)
Table-21 Microbial damage on mural paintings (Rolleke 1996)
S No Damage Microbial activity
1 Green brown red grey
surface layers (patinas)
Pigments produced by microorganisms (intra-or
extracellular) as chlorophyll and carotinoids
2 Dislodging of painting layers Use of organic binders as nutrient and energy
source
3 Acid attack of carbonates Acid produced by fungi or bacteria
4 Discolouration of pigments Redox-reactions induced by fungi and
bacteria
5 Loss of paint layer Growth of microorganisms deep into the plaster
6 Hydrolysis of synthetic
polymers Chemoorganotrophic activity of bacteria and fungi
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
27 Review of Literature
Discolorations are caused by excretion of pigments and microbiologically induced
reductionoxidation-processes (Krumbein et al 1990) Degradation of the bindings is
followed by reduction of stability Oxidation of ammonium and reduced sulphur
compounds results in acidification of the environment such as Sulphuric acid and the
variety of organic acids produced by the heterotrophs cause solubilization of calcareous
binding material and chelation of metal ions (Bock et al 1993) It is now well recognised
that wall paintings can be deteriorated by microorganisms (Ciferri 1999)The growth of
microorganisms essentially results in two types of damage aesthetic and structural
Aesthetic damage implies pigment discoloration stains and formation of a biofilm on the
painted surface Structural damage is observed as cracking and disintegration of the paint
layer formation of paint blisters and degradation of support polymers or of glues and
binders resulting in detachment of paint layer from the support The colonization of mural
paintings by bacteria and other microorganisms can have different causes Provided that
favorable environmental conditions occur nutrients for heterotrophic bacteria and fungi
can be available from metabolites of autotrophic bacteria from airborne contamination and
dripping water from animal faeces but also from organic compounds in the paint layer
itself
212 Methods of studying biodeterioration
It is now well recognized that wall paintings may be deteriorated by
microorganisms as established by several studies that linked the observed damage with the
microbial community present as reviewed by Ciferri (1999) Despite this knowledge a
reliable characterization of bacteria associated with such damage is often lacking To
obtain greater insight into the bacterial community involved in biodeterioration of mural
paintings three sites (from the necropolis at Carmona Spain and the Saint-Catherine
chapel of the castle at Herberstein Austria) were sampled In previous studies from these
sites 385 isolates were analysed by fatty acid methyl ester GC and representatives of
different fatty acid clusters were further studied by 16S rRNA gene sequencing
(Heyrman and Swings 2001) Several of these representative strains showed the highest
sequence similarity with members of the genus Arthrobacter (Heyrman et al 2005)
Jimenez and Samson (1981) analysed the microbial flora of a large fresco painted
in the late 1920s in the monastery ldquoSanta Maria de la Rabidardquo (Huelva Spain) exhibiting
two types of deterioration white efflorescence and green-to-black stains
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
28 Review of Literature
Tate and Rebrikova (1990) thought autotrophic nitrifying bacteria to be the first colonisers
of damaged frescoes and building materials in the cathedral of the nativity of the Virgin in
the Pafnutii-Borovskii monastery (Russia) The bulk of research on biodeterioration of
mural paintings has focused on explaining the observed phenomena by analysing the
microflora present Following this approach a precise characterisation of the
microorganisms using a polyphasic approach was never the first goal
Only a few studies included genomic fingerprinting (16S rDNA sequence analysis)
for the characterisation of bacteria associated with damage on mural paintings
[Rolleke (1996) Pinar et al (2001)] Previous studies based on culture-dependent
techniques showed that the flora present on frescos are fungi (predominant species of
Penicillium Aspergillus Cladosporium and Engyodontium) (Guglielminetti et al 1994)
bacteria (predominant species of Bacillus Arthrobacter Micrococcus Streptomyces and
Pseudomonas) (Heyrman et al 1999) cyanobacteria and eukaryotic algae (species of
Nostoc Lyngbya and Chlorophyceae) (Arino et al 1996 Calvo et al 1993) The killing
effect of an antimicrobial agent on a microorganism can be assessed in several ways
(1) Lethal activity may be expressed as the rate of killing by a fixed concentration
of drug under controlled conditions This rate is determined by measuring the number of
viable bacteria at various time intervals The resulting graphic depiction is known as the
time-kill curve Bacterial killing rates are in part dependent on the class of antibiotic and
the concentration of this agent With certain classes of antibiotics (eg aminoglycosides
and fluoroquino-lones) the rate of killing increases with increased drug concentrations up
to a point of maximum effect This is termed concentration-dependent bactericidal activity
In contrast the killing rates of szlig-lactam agents and vancomycin are relatively slow and
continue only as long as the concentrations are in excess of the MIC This rate of killing is
termed time-dependent bactericidal activity
(2) The minimal concentration of drug needed to kill most of the viable organisms
after incubation for a fixed length of time (generally 24 hours) under a given set of
conditions is the most common estimation of bactericidal activity and is known as either
the minimal bactericidal concentration (MBC) or the minimal lethal concentration (MLC)
It will be referred to in this document as the MBC Unfortunately the definition of the
MBC (999 killing of the final inoculum) is somewhat arbitrary and separates the
bacteria into two populations ndash a segrega-tion which might not have biological relevance
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
29 Review of Literature
The determination of the MBC moreover is so subject to methodologic variables that the
clinical relevance of MBCs is nearly impossible to assess particularly for certain pathogen
and drug combinations (eg Staphylococci and beta-lactam agents)
(3) The serum of a patient receiving an antibiotic may be tested against the
infecting microorganism This can be done using time-kill curve methodology (ie serum
bactericidal rate) or using dilution methodology (ie serum bactericidal titer) The
principles of these methods as well as the influence of biological and technical factors are
similar (Barry et al 1999)
213 Microbial flora associated with deteriorated mural paintings
A great deal of research has been done in this field mainly by using cultivation dependent
methods However by using culture-dependent methods only a very small proportion of
microorganisms can be obtained Far less than 1 of organisms in the environment can be
cultivated by standard cultivation techniques (Pace 1996) Recent studies have shown that
culture-dependent techniques yielded mainly sporeforming bacteria suggesting that plating
leads to an over estimation of the number of spore-forming bacteria A wide number of
investigations have shown that in addition to chemical and physical processes
microorganisms play a major role in degradation of objects of art such as paintings stone-
works wood paper masonry leather parchment glass and metal (Ripka 2005)
A) Bacteria
In general growth of diverse organisms on mural paintings is supported by
humidity slight alkaline pH values and the presence of organic and inorganic nutrient
sources (Weirich 1989) In mural paintings pigments are suspended in water or oil often
binders such as casein and milk are used and they are supplied on the damp lime plaster
(Ciferri 1999) The calcium carbonate formed on contact with air consolidates the
pigments Thus frescos contain mainly inorganic components While chemoautotrophic
nitrifiers and thiobacilli obtain their energy for growth by oxidizing ammonium and
reducing sulphur-compounds respectively heterotrophic bacteria and fungi depend on
organically bound carbon [Tate et al (1991) Lazar (1971) Petushkova et al (1986)
Jimenez et al (1981)] Thus primary colonization of photoautotrophic Cyanobacteria
chemolithoautotrophic nitrifying bacteria and sulphuric acid producing thiobacilli represent
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
30 Review of Literature
the first supply of organic matter The death and lysis of such bacteria promotes the
secondary settlement of heterotrophic bacteria and fungal populations (Calvo et al 1991)
Bacteria may derive from plants or pollen as many sequences obtained in this study
gave high score similarities with bacteria isolated from plants like Moraxella osloensis
Enterobacter cloace Enterobacter agglomerans and Pantoea endophytica Bacteria may
also derive from animal faeces like flies Bacillus Pseudomonas Aeromonas and Panteoa
(Ripka 2005) As Lazar and Dumitru (1973) reported studying mural paintings in a
Romanian monastery the genera Bacillus Arthrobacter and Pseudomonas have been
proved to produce salt efflorescences and were even considered to cause the blanching
phenomenon of frescoes (Jimenez et al 2000) Predominant bacterial genera are Bacillus
Streptomyces Arthrobacter Micrococcus and Pseudomonas [Weirich (1989)
Tate et al (1990) Arroyo et al (1997) Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
B) Fungi
It may be concluded that there is wide variety of fungal forms present on mural
paintings but Aspergillus and Alternaria were found dominating from all the experimental
sites next to them were Cladosporium Drechestera Fusarium Curvularia Chaetomium
Memnoniella Mycelia sterelai Pencillium Emericella Stachybotrytis Trichoderma
Phoma Monodictys Humicola and Epicoccum (Garg et al 1995)
The fungal genera most commonly found in lists of isolated taxa given in literature
are Alternaria Aspergillus Chaetomium Cladosporium Fusarium Penicillium and
Verticullum [Weirich (1989) Tate et al (1990) Guglielminetti et al (1994)
Garg et al (1995) Berner et al (1997) Ciferri (1999)] Some fungi having hard fruiting
bodies represented by sclerotia pycnidia perithecia cleistothecia and stroma could
organize themselves inside the painted layer Many fungal forms having such structures
were identified from our experimental sites viz Emericella nidulans A flavus
Chaetomium sp and Phoma sp etc These structures with little increase in humidity may
cause swelling in the paint film (Garg 1995)
Strains of species of Alternaria and Cladosporium both of them identified on the
mural paintings of the Palace of Schoumlnbrunn are the most common genera isolated from
stone and mural paintings in indoor environments with standard cultivation methods
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
31 Review of Literature
(Ventosa 2004) Saprophytic species of the genus Cladosporium are among the most
abundant fungi isolated in saltern samples Commonly isolated Cyanobacteria belong to
Nostoc and eukaryotic algae to Lyngbya and members of the Chlorophyceae such as
Chlorella Pseudococcomyxa and Pseudopleurococcus [Gorbushina et al (1987)
Calvo et al (1993) Arino et al (1996)]
They grow optimally on media with low water activity due to high salt or sugar
concentrations seem to propagate 70 vegetatively in the salterns and are thus
halotolerantosmotolerant species rather than simple flush-through occurrences
Cladiosporum herbarum was frequently isolated from hypersaline waters dead and dying
plant material air soil food fruit cereals paint and textiles (Ventosa 2004)
C) Algae
Most of the painted areas in temperature climate became covered with green algae
(Pleurococcus Protococcus and Trentopholia) while under tropical conditions blue green
algae of the genera Oscillatoria and Sytonema predominated (Garg 1995) The main
factors which contribute to the growth of algae on wall paintings are the presence of
moisture in the plaster as well as availability of visible light These conditions are quite
prevalent in the tropical climate but in temperature regions also algal growth on wall
paintings have been reported [Tonolo et al (1961) Pietrini et al (1991)]
D) Actinomycetes
Usually literature refers to specific aspects eg the occurrence of cyanobacteria
and algae in caves with natural openings to sunlight or those with artificial lighting fungi
and so forth Actinomycetes have been considered to be mainly confined to soils where
they find their natural habitat but despite intensive studies there are still many gaps in our
knowledge of the role played by actinomycetes in soil processes and biodegrations of
murals cave paintings (Groth et al 1999) In addition halophilic bacteria actinomycetes
and cyanobacteria are also capable of growing on salt-affected mural paintings
(Karbowska 2003)
Monte and Ferrari (1993) reviewed the mechanisms of biodeterioration in tombs
and underground churches The role of actinomycetes in the deterioration of frescoes in
hypogean environments was stressed by Agarossi et al (1985) Monte and Ferrari (1993)
Giacobini et al (1987) described the serious damage suffered by a whole series of famous
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
32 Review of Literature
frescoes in underground environments Actinomycetes were isolated from these mural
paintings located in crypts caves and tombs About 200 strains of actinomycetes were
isolated 60 of which were identified The most frequent species were Streptomyces albus
S cinereoruber S griseolus S vinaceus and some members of the Nocardia genus
Heterotrophic bacteria and actinomycetes were the most abundant microorganisms
on the frescoes of Etruscan tombs (Agarossi et al 1985) Bettini et al (1977) studied
some of the oldest Etruscan tombs (7th to 4th century BC) and found white-grey patinas
and spots from streptomycetes in the mural paintings They related the biodeterioration to
the microclimatic conditions (eg lower temperatures high RH) Monte and Ferrari (1993)
considered that colonization of the mural paintings was the result of selective competitive
and inhibitory dynamics among different microorganisms under different and changing
environmental conditions The pigments excreted by some actinomycetes were responsible
for the violet stains found on the walls of tombs in Tarquinia Similar stains were observed
in one of the Roman tombs the Circular Mausoleum the Necropolis of Carmona Spain
from which a Streptomyces sp producing violet pigments in culture media was isolated
214 Identification of biodeteriogens
The possibility of pigments and biodeteriogens identification in frescos and stone
monitoring is offered mostly by vibrational spectroscopy infrared thermography laser
induced fluorescence (LIF) laser induced breakdown spectroscopy (LIBS) XRF (X-Ray
Fluorescence) IR and UV emission Among them laser based methods allowing for in
situ or remote characterization of artwork surface were applied successfully for
prospecting diagnosis and maintenance (Colao et al 2005) The rep-PCR fingerprinting
of the isolates allowed determination of their genotypic diversity Studies that have
compared rep-PCR genomic fingerprint analysis with DNAndashDNA relatedness studies have
shown that the two techniques yield results that are in close agreement [Nick et al (1999)
Rademaker et al (2000)] These studies therefore suggest that rep-PCR fingerprinting can
be used as a genomic screening method to differentiate at the species level and to select
representatives for DNAndashDNA reassociation experiments (Heymann et al 2003)
The characterisation of bacteria was for example often limited to isolation from
group-specific media followed by microscopy [Sorlini et al (1987) Weirich (1989)
Tate et al (1990) and in more recent studies to morphological and physiological
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
33 Review of Literature
characteristics including miniaturised and automated systems such as API and BIOLOG
[Arroyo et al (1997) Jimmenez et al (2000) and Laiz et al (2000)] or to
chemotaxonomic characteristics [Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
Wagner et al (1994) demonstrated that conventional microbiological efforts can
fail to isolate all microorganisms present in natural samples DNA-based techniques used
to identify microorganisms have revealed only a smaller fraction of bacteria isolated from
artworks (Ward et al 1990 Rolleke et al 1996) Bacterial identification using molecular
techniques especially those including the sequencing of genes coding for ribosomal
16S rRNA is very important to study bacterial communities found on artefacts One such
method is Denaturing Gradient Gel Electrophoresis (DGGE) of PCR-amplified gene
fragments coding for rRNA (Muyzer et al 1993) that allows the separation of partial
16S rDNA amplified fragments of identical length but different sequence due to their
different melting behaviour in a gel system containing a gradient of denaturants
(Jimenez 2003)
Total genomic DNA was purified for 16S rRNA gene sequencing and rep-PCR
using a slight modification of the method of Pitcher et al (1989) as described by
Heyndrickx et al (1996) rep-PCR genomic fingerprinting was performed with the REP-
and (GTG)5 primers (Versalovic et al 1994) using the PCR conditions described
previously by Rademaker et al (1997) Electrophoresis and pattern analysis were further
performed as described by Heyrman et al (2003) 16S rRNA gene sequencing and
phylogenetic analysis were performed as described by Heyrman and Swings (2001)
Phylogenetic trees were constructed using the BioNumerics software (Applied Maths) by
applying the neighbour-joining and maximum-parsimony methods on a multiple alignment
similarity matrix The stability of relationships was assessed by a bootstrap analysis of
1000 datasets For determination of the G+C content and levels of DNAndashDNA
hybridization approximately 1 g biomass was harvested from agar plates DNA was
purified by using a combination of the protocols of Marmur (1961) and
Pitcher et al (1989) as described by Logan et al (2000) The G+C content of the DNA
was determined by HPLC (Mesbah et al 1989) using the further specifications given by
Logan et al (2000) DNAndashDNA hybridization experiments were performed using a
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
34 Review of Literature
modification of the microplate method of Ezaki et al (1989) as described by
Willems et al (2001)
215 Preservation and conservation
Nowadays the conservation and preservation of our cultural heritage is one of the
world main concerns particularly in Europe The increasing need for non-destructive
investigation tools has become a major issue as sampling is in most cases restricted in
view of the value or the uniqueness of the object Artworks as wall paintings in buildings
and monuments of historical interest are affected by environment physical (temperature
and humidity) and biological factors (biodeteriogens) and by human (pollutant releases)
impact and therefore modified over the time The term ldquoconservationrdquo may have many
different meanings in different fields Every intervention directed to the restoration and
safeguard of works of art is commonly considered as a conservation treatment For
example conservation can involve the cleaning procedures set up by chemists or the photo
documentation of the preservation of historical memory For the appropriate conservation
of works of art even the lighting systems in a museum or the control of the visitorrsquos
movements in a site should be monitored Chemical degradation which induces the flaking
of paintings and deterioration from rain wind dust and other environmental causes is
mainly responsible for the weakening of the porous structure and the surface layers of the
materials used in works of cultural heritage (Colao et al 2005)
216 Conservation history
Wall paintings are an integral part of monuments and sites and should be preserved
in situ Many of the problems affecting wall paintings are linked to the poor condition of
the building or structure its improper use lack of maintenance frequent repairs and
alterations Also frequent restorations unnecessary uncovering and use of inappropriate
methods and materials can result in irreparable damage Substandard and inadequate
practices and professional qualifications have led to unfortunate results It is for this reason
that an appropriate document covering the principles of proper conservation-restoration of
wall paintings is necessary
The Venice Charter (1964) has provided general principles for the conservation-
restoration of cultural heritage The Amsterdam Declaration (1975) introducing the
concept of integrated conservation and the Nara Document on Authenticity (1994) dealing
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
35 Review of Literature
with cultural diversity have expanded these principles Taking into account these and
additional relevant contributions such as the ICOM-CC Code of Ethics (1984) Document
of Pavia (1997) and ECCO Professional Guidelines (1997) the aim of this document is
to provide more specific principles for the protection preservation and the conservation
restoration of wall paintings This document therefore reflects basic and universally
applicable principles and practices and does not take into account particular problems of
regions or countries which can be supplemented at regional and national level by
providing further recommendations where necessary
217 Preservation techniques of the mural paintings
The removal of fat salts varnishes and pollutants from the surfaces of the works
of art are mostly done by chemical and mechanical methods At the end of the 19th
century the practices of restoration methods that do not inhibit further future interventions
was considered acceptable During the 1960s several chemicals such as polymeric resins
were synthesized and applied as a consolidation or protection agents The accepted idea
was that these substances could be removed at any time leaving a completely unaltered
substrate On the basis of origin archaeological objects can be classified as follows
(Carretti 2005)
1 Inorganic It includes siliceous and nonsiliceous materials Archaeological materials
produced from stones terracotta ceramics and glass can be included under siliceous
materials whereas objects made of metals can be included under nonsiliceous inorganic
materials Again metal objects can be classified as ferrous metals and non-ferrous metals
Objects made of iron are termed as ferrous metal objects whereas metal objects made from
other than iron is termed as non-ferrous metal objects
2 Organic It includes archival and anthropological materials Again archival materials
include paper bhojapatra tadapatra textiles wooden objects miniature paintings whereas
anthropological objects include bone and ivory leather feather and fur etc
In the past restoration of paintings and other old artwork often involved application
of acrylic resins to consolidate and protect them One of the most important tasks for
modern restorers is thus to remove these layers because it turns out that acrylic resins not
only by drastically changing the optics of the treated artwork but in many cases they
accelerate their degradation The scientists use an oil-in-water microemulsion with the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
36 Review of Literature
organic solvent para-xylene as the oil component The matrix makes the cleaning agent
viscous so that it cannot enter very far into the pores of a painting (Carretti 2005)
Nanoparticle treatment is the logical evolution of the Ferroni-Dini method
Dispersions of kinetically stable Ca (OH)2 nanoparticles in non-aqueous solvents solved
most of the drawbacks of the microsized powders Stable dispersions of calcium hydroxide
have been successfully applied (replacing polymers) as fixatives to re-adhere lifted paint
layers during many restoration workshops in Italy and in Europe as a consolidant The
FerronindashDini method (two steps the application of a saturated solution of ammonium
carbonate (NH4)2CO3 and the treatment with a barium hydroxide solution Ba(OH)2 also
called the barium method has long been the acknowledged method for the removal of
salts that threaten paintings reinforcing at the same time the porous structure However
commercially available carbonates and hydroxide powders have dimensions of several
micrometres much larger than the pores on the paint surface This means they donrsquot
penetrate the painting well and there is also a risk of damaging the artwork by a white
glaze forming on the surface (Berger 2006) Restoration should provide the reinforcement
of the porous structure and the consolidation of the surface layer of arte facts A few
simple principles can be considered to define the most appropriate restoration method
1) The treatment should be reversible so that one can revert to the original status of the
work of art at any desired time
2) All the applied chemicals must ensure the maximum durability and the chemical
inertness
3) The applied chemicals must invert the degradation processes without altering the
chemical composition of the artefacts and their physico-chemical and mechanical
properties (Baglioni 2006)
218 Commercial preservative used for preservation of mural paintings
Cleaning was done using soft brushes vacuum cleaner and Gumma paine (dough)
a natural latex sponge Areas near the window were very dirty with black soot and were
cleaned with micro fibrous cloths moistened with synperonic N (surfactant alkyl phenol
ethoxylate based on nonyl phenol) and neutralized with clean water In several places the
paint layers had separated from the substrate (exfoli-ation) In that cases loose paint flakes
were stuck back using Paraloid B72 (10 solution in ethanol) as sparingly as possible
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
37 Review of Literature
Paraloid was injected with syringe behind the exfoliated area twice pushed and held back
with Melinex (polyester film) until fixed on the third application (Bionda et al 2002)
In a period of significant growth of molds and intensive efforts to stop the mold
contamination some of the lines of certain paintings were obscured or faded Solutions of
ethanol formalin 91 and Thiabendazole (TBZ) were used but they were not very
effective Para-formaldehyde fumigation was adopted beginning in 1981 to establish an
emergency treatment sensitivity of microorganisms from studied samples was tested
against Desogen by adding 1-3 (v v) in serial dilutions The best concentration
3 (vv) was applied with a brush to prevent spreading of the spores In order to overcome
the problem of fungal attack suitable fungicides carbendizeme or kiroxy-I or 5 solute of
N formaldehyde can be used Shellac solution in spirit or 2 solution of polyvinaycletate
in toluene can be used as preservative and consolidantsTo control insect and fungal attack
fumigants like pyrethrum DDT or 5 solution of sodium penta chlorophenate in kerosene
oil 2 to 5 solution of PVA in toluene or 2 to 5 solution of paraloid B-72 in toluene or
acetone be used (Miura 2009) Microclimatic conditions constitute a critical factor in the
conservation of cave paintings The unstable microclimatic condition is one of the factors
that always affect the state of conservation of mural paintings In the environmental-
monument system knowledge of the functional environment and climatic conditions of the
surroundings are necessary for the identification of causes of decay (Singh 2011)
Furthermore the risk of formation of indoor bioaerosols in residential and public
buildings (offices schools museums etc) has attracted interest in the last years due to
socio-economic as well as sanitary reasons (Ripka 2005) Thus it is important in aspects of
health and maintenance of Cultural Heritage to analyse the complete microflora to further
develop biocides for harmful microorganisms and methods for restoration of damaged
objects of art The biocidal testing was carried out on one representative algal species of
the two classes of algae viz Chlorococcum sp (green) and Chroococcus sp (blue-green)
found to be common in all the samples Efficiency tests were carried out both in liquid as
well as solid media containing algal suspensions by adding a biocide solution of known
concentration and determining the growth of the microorganism after the incubation
period The biocides used for the past studies were
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
24 Review of Literature
Traditionally the study of microflora which causes this biodeterioration was based
on classical cultivation methods that were mainly useful to study the physiological
potential of microorganisms but do not provide information on all microbial communities
to be found in excavated artifacts Indeed many studies using culture-independent
techniques which cultivate microorganisms from different environments may often
represent only minor components of the microbial community as a whole It is generally
accepted that cultivation methods recover less than 1 of the total microorganisms present
in environmental samples (Ward et al 1990 Amann et al 1995) Hence microbial
investigations based only on cultivation strategies cannot be regarded as reliable in terms
of reflecting the microbial diversity present in objects of art (Osburn et al 2011)
Early workers suggested that the presence of living microorganisms on stone
increased its susceptibility to damage through their water-binding capacity It has recently
been reported that the mineralogy porosity surface roughness and capacity to collect
water and organic materials control its bioreceptivity and tendency to biodeterioration
(Diakumaku 1995) In addition environmental factors as temperature light pH and
relative humidity affect the number and type of colonising species (Tiano et al 1995) and
hence the progress of colonisation Biofilms on decayed stones consist on mixed microbial
populations embedded in a polymeric matrix Fungi algae filamentous and unicellular
bacteria are found in these complex communities A variety of bacteria have been isolated
from different stone samples confirming the dominance of Gram-positive organisms
especially spore-forming bacteria such as Bacillus and filamentous actinomycetes
(Ripka 2005)
In cultivation studies of deteriorated mural and rock paintings bacterial isolates
have frequently been attributed to the genus Bacillus (Weirich 1989 Tate and Rebrikova
1991 Gonzalez et al 1999 Heyrman et al 1999 Jimenez et al 2000) Other studies that
have included DNA-based techniques to characterize the bacterial community involved in
biodeterioration have shown that a substantial part of the bacterial population is made up of
so far unknown species (Altenburger et al 1996 Rolleke et al 1996 Gurtner et al 2000
Heyrman and Swings 2001) (Heymann et al 2003)
Many potential mycotoxin producers have been detected in air and items from
indoor environments with histories of exposure to moisture for example species of
Acremonium Alternaria Aspergillus Chateomium Fusarium Eurotium Paecilomyces
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
25 Review of Literature
Penicillium Scopulariopsis Stachybotrys Trichoderma Verticillium and Wallemia
(Peltola et al 2001 Pieckova et al 2001) Not all strains of one species produce
mycotoxins and different strains may produce different toxins Whereas toxin producing
strains are frequent in crops and outdoor vegetation toxin producing isolates from indoor
environments and non living assets have only been reported of the species Aspergillus
versicolor (Nielsen et al 1998) Stachybotrys chartarum Nikulin (1997) and
Trichoderma harzianum (Peltola et al 2001) Streptomyces griseus strains producing
valinomycin occur in environments where humans can get exposed
(Andersson et al 2002) The biological properties and toxicity mechanisms of cereulide
were identical to those by valinomycin (Mikkola et al 1999 Salonen et al 2001)
The genus Paenibacillus was first proposed by Ash et al (1993) and its description
was emended by Shida et al (1997) The genus Paenibacillus is under intensive taxonomic
investigation with ten species having been formally described in the last year Heyrman amp
Swings (2001) isolated a strain originally classified as Paenibacillus sp LMG 19508
from biodeteriorated mural paintings in the Servilia tomb at the Roman necropolis of
Carmona in Seville Spain (Smerda et al 2006) Building stone and wall paintings contain
a variety of hydroscopic salts including carbonates chlorides nitrates sulfates etc
dispersed within the porous material or locally concentrated These salts are solubilised
and migrate with the water in and out of the stone Due to changes in physical parameters
the so called salt efflorescences appear on the surfaces providing extremely saline
environments and building niches for settlement of halophilic microorganisms Halite and
other hygroscopic salts can retain considerable quantities of moisture when entrapped in
the building materials and thus favouring the bacterial growth (Ripka 2005)
It is demonstrated that water-damaged indoor building materials contained
substances of microbial origin extremely toxic to eukaryotic cells and large quantities of
several microbial species known to be potentially toxic or immunopotentiating These
include peptidoglycans Gram-negative endotoxin β-13-D glucans lipoglycans and
teichoic acids and mycotoxins (Jimenez 2000) In turn these microorganisms can mediate
the crystallization process These crystallizations can produce destructive effects Some
salts may crystallize or recrystallize to different hydrates which occupy a larger space and
exert additional pressure producing cracking powdering and flaking
(Jimenez and Laiz 2000)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
26 Review of Literature
211 Types of deterioration on mural paintings
The frescos represent a variety of ecological niches where primary colonization is
due to photoautotrophic and chemolithoautotrophic microorganisms followed by
secondary colonization due to heterotrophic bacteria that obtain nutrients from various
sources (metabolites of autotrophic bacteria airborne organic contamination animal faeces
and organic compounds in the paint layers themselves) Microbial-induced deterioration
processes cause structural as well as aesthetic damage to wall paintings such as the
discoloration of materials the formation of crusts on surfaces and the loss of material
(Sarro et al 2006 Osburn et al 2011) Halophilic bacteria and archaea were thought to
be found only in extreme environments like salt lakes or black smokers However it has
been shown that mural paintings and stones are a common habitat for extremely salt
tolerant and moderate halophilic (Ripka 2005) Microbial induced deterioration processes
can cause different kinds of alterations such as discolouration of materials the formation of
crusts on surfaces and the loss of material which leads to structural damage (Ripka 2005)
First of all microorganisms can cause severe problems due to the excretion of aggressive
metabolic products such as organic or inorganic acids Secondly material components can
be used as substrates for microbial metabolism Exoenzymes such as cellulases proteases
tannases beta-glucosidase produced by fungi and bacteria are responsible for hydrolysis of
cellulose and proteins Further examples are mechanical processes caused by swelling and
shrinking of slime or mycelia penetrating inside plaster of the painting resulting in loss of
cohesion and detachment of the paint layer (Rolleke 1996 Gurtner et al 2000)
Table-21 Microbial damage on mural paintings (Rolleke 1996)
S No Damage Microbial activity
1 Green brown red grey
surface layers (patinas)
Pigments produced by microorganisms (intra-or
extracellular) as chlorophyll and carotinoids
2 Dislodging of painting layers Use of organic binders as nutrient and energy
source
3 Acid attack of carbonates Acid produced by fungi or bacteria
4 Discolouration of pigments Redox-reactions induced by fungi and
bacteria
5 Loss of paint layer Growth of microorganisms deep into the plaster
6 Hydrolysis of synthetic
polymers Chemoorganotrophic activity of bacteria and fungi
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
27 Review of Literature
Discolorations are caused by excretion of pigments and microbiologically induced
reductionoxidation-processes (Krumbein et al 1990) Degradation of the bindings is
followed by reduction of stability Oxidation of ammonium and reduced sulphur
compounds results in acidification of the environment such as Sulphuric acid and the
variety of organic acids produced by the heterotrophs cause solubilization of calcareous
binding material and chelation of metal ions (Bock et al 1993) It is now well recognised
that wall paintings can be deteriorated by microorganisms (Ciferri 1999)The growth of
microorganisms essentially results in two types of damage aesthetic and structural
Aesthetic damage implies pigment discoloration stains and formation of a biofilm on the
painted surface Structural damage is observed as cracking and disintegration of the paint
layer formation of paint blisters and degradation of support polymers or of glues and
binders resulting in detachment of paint layer from the support The colonization of mural
paintings by bacteria and other microorganisms can have different causes Provided that
favorable environmental conditions occur nutrients for heterotrophic bacteria and fungi
can be available from metabolites of autotrophic bacteria from airborne contamination and
dripping water from animal faeces but also from organic compounds in the paint layer
itself
212 Methods of studying biodeterioration
It is now well recognized that wall paintings may be deteriorated by
microorganisms as established by several studies that linked the observed damage with the
microbial community present as reviewed by Ciferri (1999) Despite this knowledge a
reliable characterization of bacteria associated with such damage is often lacking To
obtain greater insight into the bacterial community involved in biodeterioration of mural
paintings three sites (from the necropolis at Carmona Spain and the Saint-Catherine
chapel of the castle at Herberstein Austria) were sampled In previous studies from these
sites 385 isolates were analysed by fatty acid methyl ester GC and representatives of
different fatty acid clusters were further studied by 16S rRNA gene sequencing
(Heyrman and Swings 2001) Several of these representative strains showed the highest
sequence similarity with members of the genus Arthrobacter (Heyrman et al 2005)
Jimenez and Samson (1981) analysed the microbial flora of a large fresco painted
in the late 1920s in the monastery ldquoSanta Maria de la Rabidardquo (Huelva Spain) exhibiting
two types of deterioration white efflorescence and green-to-black stains
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
28 Review of Literature
Tate and Rebrikova (1990) thought autotrophic nitrifying bacteria to be the first colonisers
of damaged frescoes and building materials in the cathedral of the nativity of the Virgin in
the Pafnutii-Borovskii monastery (Russia) The bulk of research on biodeterioration of
mural paintings has focused on explaining the observed phenomena by analysing the
microflora present Following this approach a precise characterisation of the
microorganisms using a polyphasic approach was never the first goal
Only a few studies included genomic fingerprinting (16S rDNA sequence analysis)
for the characterisation of bacteria associated with damage on mural paintings
[Rolleke (1996) Pinar et al (2001)] Previous studies based on culture-dependent
techniques showed that the flora present on frescos are fungi (predominant species of
Penicillium Aspergillus Cladosporium and Engyodontium) (Guglielminetti et al 1994)
bacteria (predominant species of Bacillus Arthrobacter Micrococcus Streptomyces and
Pseudomonas) (Heyrman et al 1999) cyanobacteria and eukaryotic algae (species of
Nostoc Lyngbya and Chlorophyceae) (Arino et al 1996 Calvo et al 1993) The killing
effect of an antimicrobial agent on a microorganism can be assessed in several ways
(1) Lethal activity may be expressed as the rate of killing by a fixed concentration
of drug under controlled conditions This rate is determined by measuring the number of
viable bacteria at various time intervals The resulting graphic depiction is known as the
time-kill curve Bacterial killing rates are in part dependent on the class of antibiotic and
the concentration of this agent With certain classes of antibiotics (eg aminoglycosides
and fluoroquino-lones) the rate of killing increases with increased drug concentrations up
to a point of maximum effect This is termed concentration-dependent bactericidal activity
In contrast the killing rates of szlig-lactam agents and vancomycin are relatively slow and
continue only as long as the concentrations are in excess of the MIC This rate of killing is
termed time-dependent bactericidal activity
(2) The minimal concentration of drug needed to kill most of the viable organisms
after incubation for a fixed length of time (generally 24 hours) under a given set of
conditions is the most common estimation of bactericidal activity and is known as either
the minimal bactericidal concentration (MBC) or the minimal lethal concentration (MLC)
It will be referred to in this document as the MBC Unfortunately the definition of the
MBC (999 killing of the final inoculum) is somewhat arbitrary and separates the
bacteria into two populations ndash a segrega-tion which might not have biological relevance
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
29 Review of Literature
The determination of the MBC moreover is so subject to methodologic variables that the
clinical relevance of MBCs is nearly impossible to assess particularly for certain pathogen
and drug combinations (eg Staphylococci and beta-lactam agents)
(3) The serum of a patient receiving an antibiotic may be tested against the
infecting microorganism This can be done using time-kill curve methodology (ie serum
bactericidal rate) or using dilution methodology (ie serum bactericidal titer) The
principles of these methods as well as the influence of biological and technical factors are
similar (Barry et al 1999)
213 Microbial flora associated with deteriorated mural paintings
A great deal of research has been done in this field mainly by using cultivation dependent
methods However by using culture-dependent methods only a very small proportion of
microorganisms can be obtained Far less than 1 of organisms in the environment can be
cultivated by standard cultivation techniques (Pace 1996) Recent studies have shown that
culture-dependent techniques yielded mainly sporeforming bacteria suggesting that plating
leads to an over estimation of the number of spore-forming bacteria A wide number of
investigations have shown that in addition to chemical and physical processes
microorganisms play a major role in degradation of objects of art such as paintings stone-
works wood paper masonry leather parchment glass and metal (Ripka 2005)
A) Bacteria
In general growth of diverse organisms on mural paintings is supported by
humidity slight alkaline pH values and the presence of organic and inorganic nutrient
sources (Weirich 1989) In mural paintings pigments are suspended in water or oil often
binders such as casein and milk are used and they are supplied on the damp lime plaster
(Ciferri 1999) The calcium carbonate formed on contact with air consolidates the
pigments Thus frescos contain mainly inorganic components While chemoautotrophic
nitrifiers and thiobacilli obtain their energy for growth by oxidizing ammonium and
reducing sulphur-compounds respectively heterotrophic bacteria and fungi depend on
organically bound carbon [Tate et al (1991) Lazar (1971) Petushkova et al (1986)
Jimenez et al (1981)] Thus primary colonization of photoautotrophic Cyanobacteria
chemolithoautotrophic nitrifying bacteria and sulphuric acid producing thiobacilli represent
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
30 Review of Literature
the first supply of organic matter The death and lysis of such bacteria promotes the
secondary settlement of heterotrophic bacteria and fungal populations (Calvo et al 1991)
Bacteria may derive from plants or pollen as many sequences obtained in this study
gave high score similarities with bacteria isolated from plants like Moraxella osloensis
Enterobacter cloace Enterobacter agglomerans and Pantoea endophytica Bacteria may
also derive from animal faeces like flies Bacillus Pseudomonas Aeromonas and Panteoa
(Ripka 2005) As Lazar and Dumitru (1973) reported studying mural paintings in a
Romanian monastery the genera Bacillus Arthrobacter and Pseudomonas have been
proved to produce salt efflorescences and were even considered to cause the blanching
phenomenon of frescoes (Jimenez et al 2000) Predominant bacterial genera are Bacillus
Streptomyces Arthrobacter Micrococcus and Pseudomonas [Weirich (1989)
Tate et al (1990) Arroyo et al (1997) Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
B) Fungi
It may be concluded that there is wide variety of fungal forms present on mural
paintings but Aspergillus and Alternaria were found dominating from all the experimental
sites next to them were Cladosporium Drechestera Fusarium Curvularia Chaetomium
Memnoniella Mycelia sterelai Pencillium Emericella Stachybotrytis Trichoderma
Phoma Monodictys Humicola and Epicoccum (Garg et al 1995)
The fungal genera most commonly found in lists of isolated taxa given in literature
are Alternaria Aspergillus Chaetomium Cladosporium Fusarium Penicillium and
Verticullum [Weirich (1989) Tate et al (1990) Guglielminetti et al (1994)
Garg et al (1995) Berner et al (1997) Ciferri (1999)] Some fungi having hard fruiting
bodies represented by sclerotia pycnidia perithecia cleistothecia and stroma could
organize themselves inside the painted layer Many fungal forms having such structures
were identified from our experimental sites viz Emericella nidulans A flavus
Chaetomium sp and Phoma sp etc These structures with little increase in humidity may
cause swelling in the paint film (Garg 1995)
Strains of species of Alternaria and Cladosporium both of them identified on the
mural paintings of the Palace of Schoumlnbrunn are the most common genera isolated from
stone and mural paintings in indoor environments with standard cultivation methods
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
31 Review of Literature
(Ventosa 2004) Saprophytic species of the genus Cladosporium are among the most
abundant fungi isolated in saltern samples Commonly isolated Cyanobacteria belong to
Nostoc and eukaryotic algae to Lyngbya and members of the Chlorophyceae such as
Chlorella Pseudococcomyxa and Pseudopleurococcus [Gorbushina et al (1987)
Calvo et al (1993) Arino et al (1996)]
They grow optimally on media with low water activity due to high salt or sugar
concentrations seem to propagate 70 vegetatively in the salterns and are thus
halotolerantosmotolerant species rather than simple flush-through occurrences
Cladiosporum herbarum was frequently isolated from hypersaline waters dead and dying
plant material air soil food fruit cereals paint and textiles (Ventosa 2004)
C) Algae
Most of the painted areas in temperature climate became covered with green algae
(Pleurococcus Protococcus and Trentopholia) while under tropical conditions blue green
algae of the genera Oscillatoria and Sytonema predominated (Garg 1995) The main
factors which contribute to the growth of algae on wall paintings are the presence of
moisture in the plaster as well as availability of visible light These conditions are quite
prevalent in the tropical climate but in temperature regions also algal growth on wall
paintings have been reported [Tonolo et al (1961) Pietrini et al (1991)]
D) Actinomycetes
Usually literature refers to specific aspects eg the occurrence of cyanobacteria
and algae in caves with natural openings to sunlight or those with artificial lighting fungi
and so forth Actinomycetes have been considered to be mainly confined to soils where
they find their natural habitat but despite intensive studies there are still many gaps in our
knowledge of the role played by actinomycetes in soil processes and biodegrations of
murals cave paintings (Groth et al 1999) In addition halophilic bacteria actinomycetes
and cyanobacteria are also capable of growing on salt-affected mural paintings
(Karbowska 2003)
Monte and Ferrari (1993) reviewed the mechanisms of biodeterioration in tombs
and underground churches The role of actinomycetes in the deterioration of frescoes in
hypogean environments was stressed by Agarossi et al (1985) Monte and Ferrari (1993)
Giacobini et al (1987) described the serious damage suffered by a whole series of famous
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
32 Review of Literature
frescoes in underground environments Actinomycetes were isolated from these mural
paintings located in crypts caves and tombs About 200 strains of actinomycetes were
isolated 60 of which were identified The most frequent species were Streptomyces albus
S cinereoruber S griseolus S vinaceus and some members of the Nocardia genus
Heterotrophic bacteria and actinomycetes were the most abundant microorganisms
on the frescoes of Etruscan tombs (Agarossi et al 1985) Bettini et al (1977) studied
some of the oldest Etruscan tombs (7th to 4th century BC) and found white-grey patinas
and spots from streptomycetes in the mural paintings They related the biodeterioration to
the microclimatic conditions (eg lower temperatures high RH) Monte and Ferrari (1993)
considered that colonization of the mural paintings was the result of selective competitive
and inhibitory dynamics among different microorganisms under different and changing
environmental conditions The pigments excreted by some actinomycetes were responsible
for the violet stains found on the walls of tombs in Tarquinia Similar stains were observed
in one of the Roman tombs the Circular Mausoleum the Necropolis of Carmona Spain
from which a Streptomyces sp producing violet pigments in culture media was isolated
214 Identification of biodeteriogens
The possibility of pigments and biodeteriogens identification in frescos and stone
monitoring is offered mostly by vibrational spectroscopy infrared thermography laser
induced fluorescence (LIF) laser induced breakdown spectroscopy (LIBS) XRF (X-Ray
Fluorescence) IR and UV emission Among them laser based methods allowing for in
situ or remote characterization of artwork surface were applied successfully for
prospecting diagnosis and maintenance (Colao et al 2005) The rep-PCR fingerprinting
of the isolates allowed determination of their genotypic diversity Studies that have
compared rep-PCR genomic fingerprint analysis with DNAndashDNA relatedness studies have
shown that the two techniques yield results that are in close agreement [Nick et al (1999)
Rademaker et al (2000)] These studies therefore suggest that rep-PCR fingerprinting can
be used as a genomic screening method to differentiate at the species level and to select
representatives for DNAndashDNA reassociation experiments (Heymann et al 2003)
The characterisation of bacteria was for example often limited to isolation from
group-specific media followed by microscopy [Sorlini et al (1987) Weirich (1989)
Tate et al (1990) and in more recent studies to morphological and physiological
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
33 Review of Literature
characteristics including miniaturised and automated systems such as API and BIOLOG
[Arroyo et al (1997) Jimmenez et al (2000) and Laiz et al (2000)] or to
chemotaxonomic characteristics [Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
Wagner et al (1994) demonstrated that conventional microbiological efforts can
fail to isolate all microorganisms present in natural samples DNA-based techniques used
to identify microorganisms have revealed only a smaller fraction of bacteria isolated from
artworks (Ward et al 1990 Rolleke et al 1996) Bacterial identification using molecular
techniques especially those including the sequencing of genes coding for ribosomal
16S rRNA is very important to study bacterial communities found on artefacts One such
method is Denaturing Gradient Gel Electrophoresis (DGGE) of PCR-amplified gene
fragments coding for rRNA (Muyzer et al 1993) that allows the separation of partial
16S rDNA amplified fragments of identical length but different sequence due to their
different melting behaviour in a gel system containing a gradient of denaturants
(Jimenez 2003)
Total genomic DNA was purified for 16S rRNA gene sequencing and rep-PCR
using a slight modification of the method of Pitcher et al (1989) as described by
Heyndrickx et al (1996) rep-PCR genomic fingerprinting was performed with the REP-
and (GTG)5 primers (Versalovic et al 1994) using the PCR conditions described
previously by Rademaker et al (1997) Electrophoresis and pattern analysis were further
performed as described by Heyrman et al (2003) 16S rRNA gene sequencing and
phylogenetic analysis were performed as described by Heyrman and Swings (2001)
Phylogenetic trees were constructed using the BioNumerics software (Applied Maths) by
applying the neighbour-joining and maximum-parsimony methods on a multiple alignment
similarity matrix The stability of relationships was assessed by a bootstrap analysis of
1000 datasets For determination of the G+C content and levels of DNAndashDNA
hybridization approximately 1 g biomass was harvested from agar plates DNA was
purified by using a combination of the protocols of Marmur (1961) and
Pitcher et al (1989) as described by Logan et al (2000) The G+C content of the DNA
was determined by HPLC (Mesbah et al 1989) using the further specifications given by
Logan et al (2000) DNAndashDNA hybridization experiments were performed using a
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
34 Review of Literature
modification of the microplate method of Ezaki et al (1989) as described by
Willems et al (2001)
215 Preservation and conservation
Nowadays the conservation and preservation of our cultural heritage is one of the
world main concerns particularly in Europe The increasing need for non-destructive
investigation tools has become a major issue as sampling is in most cases restricted in
view of the value or the uniqueness of the object Artworks as wall paintings in buildings
and monuments of historical interest are affected by environment physical (temperature
and humidity) and biological factors (biodeteriogens) and by human (pollutant releases)
impact and therefore modified over the time The term ldquoconservationrdquo may have many
different meanings in different fields Every intervention directed to the restoration and
safeguard of works of art is commonly considered as a conservation treatment For
example conservation can involve the cleaning procedures set up by chemists or the photo
documentation of the preservation of historical memory For the appropriate conservation
of works of art even the lighting systems in a museum or the control of the visitorrsquos
movements in a site should be monitored Chemical degradation which induces the flaking
of paintings and deterioration from rain wind dust and other environmental causes is
mainly responsible for the weakening of the porous structure and the surface layers of the
materials used in works of cultural heritage (Colao et al 2005)
216 Conservation history
Wall paintings are an integral part of monuments and sites and should be preserved
in situ Many of the problems affecting wall paintings are linked to the poor condition of
the building or structure its improper use lack of maintenance frequent repairs and
alterations Also frequent restorations unnecessary uncovering and use of inappropriate
methods and materials can result in irreparable damage Substandard and inadequate
practices and professional qualifications have led to unfortunate results It is for this reason
that an appropriate document covering the principles of proper conservation-restoration of
wall paintings is necessary
The Venice Charter (1964) has provided general principles for the conservation-
restoration of cultural heritage The Amsterdam Declaration (1975) introducing the
concept of integrated conservation and the Nara Document on Authenticity (1994) dealing
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
35 Review of Literature
with cultural diversity have expanded these principles Taking into account these and
additional relevant contributions such as the ICOM-CC Code of Ethics (1984) Document
of Pavia (1997) and ECCO Professional Guidelines (1997) the aim of this document is
to provide more specific principles for the protection preservation and the conservation
restoration of wall paintings This document therefore reflects basic and universally
applicable principles and practices and does not take into account particular problems of
regions or countries which can be supplemented at regional and national level by
providing further recommendations where necessary
217 Preservation techniques of the mural paintings
The removal of fat salts varnishes and pollutants from the surfaces of the works
of art are mostly done by chemical and mechanical methods At the end of the 19th
century the practices of restoration methods that do not inhibit further future interventions
was considered acceptable During the 1960s several chemicals such as polymeric resins
were synthesized and applied as a consolidation or protection agents The accepted idea
was that these substances could be removed at any time leaving a completely unaltered
substrate On the basis of origin archaeological objects can be classified as follows
(Carretti 2005)
1 Inorganic It includes siliceous and nonsiliceous materials Archaeological materials
produced from stones terracotta ceramics and glass can be included under siliceous
materials whereas objects made of metals can be included under nonsiliceous inorganic
materials Again metal objects can be classified as ferrous metals and non-ferrous metals
Objects made of iron are termed as ferrous metal objects whereas metal objects made from
other than iron is termed as non-ferrous metal objects
2 Organic It includes archival and anthropological materials Again archival materials
include paper bhojapatra tadapatra textiles wooden objects miniature paintings whereas
anthropological objects include bone and ivory leather feather and fur etc
In the past restoration of paintings and other old artwork often involved application
of acrylic resins to consolidate and protect them One of the most important tasks for
modern restorers is thus to remove these layers because it turns out that acrylic resins not
only by drastically changing the optics of the treated artwork but in many cases they
accelerate their degradation The scientists use an oil-in-water microemulsion with the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
36 Review of Literature
organic solvent para-xylene as the oil component The matrix makes the cleaning agent
viscous so that it cannot enter very far into the pores of a painting (Carretti 2005)
Nanoparticle treatment is the logical evolution of the Ferroni-Dini method
Dispersions of kinetically stable Ca (OH)2 nanoparticles in non-aqueous solvents solved
most of the drawbacks of the microsized powders Stable dispersions of calcium hydroxide
have been successfully applied (replacing polymers) as fixatives to re-adhere lifted paint
layers during many restoration workshops in Italy and in Europe as a consolidant The
FerronindashDini method (two steps the application of a saturated solution of ammonium
carbonate (NH4)2CO3 and the treatment with a barium hydroxide solution Ba(OH)2 also
called the barium method has long been the acknowledged method for the removal of
salts that threaten paintings reinforcing at the same time the porous structure However
commercially available carbonates and hydroxide powders have dimensions of several
micrometres much larger than the pores on the paint surface This means they donrsquot
penetrate the painting well and there is also a risk of damaging the artwork by a white
glaze forming on the surface (Berger 2006) Restoration should provide the reinforcement
of the porous structure and the consolidation of the surface layer of arte facts A few
simple principles can be considered to define the most appropriate restoration method
1) The treatment should be reversible so that one can revert to the original status of the
work of art at any desired time
2) All the applied chemicals must ensure the maximum durability and the chemical
inertness
3) The applied chemicals must invert the degradation processes without altering the
chemical composition of the artefacts and their physico-chemical and mechanical
properties (Baglioni 2006)
218 Commercial preservative used for preservation of mural paintings
Cleaning was done using soft brushes vacuum cleaner and Gumma paine (dough)
a natural latex sponge Areas near the window were very dirty with black soot and were
cleaned with micro fibrous cloths moistened with synperonic N (surfactant alkyl phenol
ethoxylate based on nonyl phenol) and neutralized with clean water In several places the
paint layers had separated from the substrate (exfoli-ation) In that cases loose paint flakes
were stuck back using Paraloid B72 (10 solution in ethanol) as sparingly as possible
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
37 Review of Literature
Paraloid was injected with syringe behind the exfoliated area twice pushed and held back
with Melinex (polyester film) until fixed on the third application (Bionda et al 2002)
In a period of significant growth of molds and intensive efforts to stop the mold
contamination some of the lines of certain paintings were obscured or faded Solutions of
ethanol formalin 91 and Thiabendazole (TBZ) were used but they were not very
effective Para-formaldehyde fumigation was adopted beginning in 1981 to establish an
emergency treatment sensitivity of microorganisms from studied samples was tested
against Desogen by adding 1-3 (v v) in serial dilutions The best concentration
3 (vv) was applied with a brush to prevent spreading of the spores In order to overcome
the problem of fungal attack suitable fungicides carbendizeme or kiroxy-I or 5 solute of
N formaldehyde can be used Shellac solution in spirit or 2 solution of polyvinaycletate
in toluene can be used as preservative and consolidantsTo control insect and fungal attack
fumigants like pyrethrum DDT or 5 solution of sodium penta chlorophenate in kerosene
oil 2 to 5 solution of PVA in toluene or 2 to 5 solution of paraloid B-72 in toluene or
acetone be used (Miura 2009) Microclimatic conditions constitute a critical factor in the
conservation of cave paintings The unstable microclimatic condition is one of the factors
that always affect the state of conservation of mural paintings In the environmental-
monument system knowledge of the functional environment and climatic conditions of the
surroundings are necessary for the identification of causes of decay (Singh 2011)
Furthermore the risk of formation of indoor bioaerosols in residential and public
buildings (offices schools museums etc) has attracted interest in the last years due to
socio-economic as well as sanitary reasons (Ripka 2005) Thus it is important in aspects of
health and maintenance of Cultural Heritage to analyse the complete microflora to further
develop biocides for harmful microorganisms and methods for restoration of damaged
objects of art The biocidal testing was carried out on one representative algal species of
the two classes of algae viz Chlorococcum sp (green) and Chroococcus sp (blue-green)
found to be common in all the samples Efficiency tests were carried out both in liquid as
well as solid media containing algal suspensions by adding a biocide solution of known
concentration and determining the growth of the microorganism after the incubation
period The biocides used for the past studies were
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
25 Review of Literature
Penicillium Scopulariopsis Stachybotrys Trichoderma Verticillium and Wallemia
(Peltola et al 2001 Pieckova et al 2001) Not all strains of one species produce
mycotoxins and different strains may produce different toxins Whereas toxin producing
strains are frequent in crops and outdoor vegetation toxin producing isolates from indoor
environments and non living assets have only been reported of the species Aspergillus
versicolor (Nielsen et al 1998) Stachybotrys chartarum Nikulin (1997) and
Trichoderma harzianum (Peltola et al 2001) Streptomyces griseus strains producing
valinomycin occur in environments where humans can get exposed
(Andersson et al 2002) The biological properties and toxicity mechanisms of cereulide
were identical to those by valinomycin (Mikkola et al 1999 Salonen et al 2001)
The genus Paenibacillus was first proposed by Ash et al (1993) and its description
was emended by Shida et al (1997) The genus Paenibacillus is under intensive taxonomic
investigation with ten species having been formally described in the last year Heyrman amp
Swings (2001) isolated a strain originally classified as Paenibacillus sp LMG 19508
from biodeteriorated mural paintings in the Servilia tomb at the Roman necropolis of
Carmona in Seville Spain (Smerda et al 2006) Building stone and wall paintings contain
a variety of hydroscopic salts including carbonates chlorides nitrates sulfates etc
dispersed within the porous material or locally concentrated These salts are solubilised
and migrate with the water in and out of the stone Due to changes in physical parameters
the so called salt efflorescences appear on the surfaces providing extremely saline
environments and building niches for settlement of halophilic microorganisms Halite and
other hygroscopic salts can retain considerable quantities of moisture when entrapped in
the building materials and thus favouring the bacterial growth (Ripka 2005)
It is demonstrated that water-damaged indoor building materials contained
substances of microbial origin extremely toxic to eukaryotic cells and large quantities of
several microbial species known to be potentially toxic or immunopotentiating These
include peptidoglycans Gram-negative endotoxin β-13-D glucans lipoglycans and
teichoic acids and mycotoxins (Jimenez 2000) In turn these microorganisms can mediate
the crystallization process These crystallizations can produce destructive effects Some
salts may crystallize or recrystallize to different hydrates which occupy a larger space and
exert additional pressure producing cracking powdering and flaking
(Jimenez and Laiz 2000)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
26 Review of Literature
211 Types of deterioration on mural paintings
The frescos represent a variety of ecological niches where primary colonization is
due to photoautotrophic and chemolithoautotrophic microorganisms followed by
secondary colonization due to heterotrophic bacteria that obtain nutrients from various
sources (metabolites of autotrophic bacteria airborne organic contamination animal faeces
and organic compounds in the paint layers themselves) Microbial-induced deterioration
processes cause structural as well as aesthetic damage to wall paintings such as the
discoloration of materials the formation of crusts on surfaces and the loss of material
(Sarro et al 2006 Osburn et al 2011) Halophilic bacteria and archaea were thought to
be found only in extreme environments like salt lakes or black smokers However it has
been shown that mural paintings and stones are a common habitat for extremely salt
tolerant and moderate halophilic (Ripka 2005) Microbial induced deterioration processes
can cause different kinds of alterations such as discolouration of materials the formation of
crusts on surfaces and the loss of material which leads to structural damage (Ripka 2005)
First of all microorganisms can cause severe problems due to the excretion of aggressive
metabolic products such as organic or inorganic acids Secondly material components can
be used as substrates for microbial metabolism Exoenzymes such as cellulases proteases
tannases beta-glucosidase produced by fungi and bacteria are responsible for hydrolysis of
cellulose and proteins Further examples are mechanical processes caused by swelling and
shrinking of slime or mycelia penetrating inside plaster of the painting resulting in loss of
cohesion and detachment of the paint layer (Rolleke 1996 Gurtner et al 2000)
Table-21 Microbial damage on mural paintings (Rolleke 1996)
S No Damage Microbial activity
1 Green brown red grey
surface layers (patinas)
Pigments produced by microorganisms (intra-or
extracellular) as chlorophyll and carotinoids
2 Dislodging of painting layers Use of organic binders as nutrient and energy
source
3 Acid attack of carbonates Acid produced by fungi or bacteria
4 Discolouration of pigments Redox-reactions induced by fungi and
bacteria
5 Loss of paint layer Growth of microorganisms deep into the plaster
6 Hydrolysis of synthetic
polymers Chemoorganotrophic activity of bacteria and fungi
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
27 Review of Literature
Discolorations are caused by excretion of pigments and microbiologically induced
reductionoxidation-processes (Krumbein et al 1990) Degradation of the bindings is
followed by reduction of stability Oxidation of ammonium and reduced sulphur
compounds results in acidification of the environment such as Sulphuric acid and the
variety of organic acids produced by the heterotrophs cause solubilization of calcareous
binding material and chelation of metal ions (Bock et al 1993) It is now well recognised
that wall paintings can be deteriorated by microorganisms (Ciferri 1999)The growth of
microorganisms essentially results in two types of damage aesthetic and structural
Aesthetic damage implies pigment discoloration stains and formation of a biofilm on the
painted surface Structural damage is observed as cracking and disintegration of the paint
layer formation of paint blisters and degradation of support polymers or of glues and
binders resulting in detachment of paint layer from the support The colonization of mural
paintings by bacteria and other microorganisms can have different causes Provided that
favorable environmental conditions occur nutrients for heterotrophic bacteria and fungi
can be available from metabolites of autotrophic bacteria from airborne contamination and
dripping water from animal faeces but also from organic compounds in the paint layer
itself
212 Methods of studying biodeterioration
It is now well recognized that wall paintings may be deteriorated by
microorganisms as established by several studies that linked the observed damage with the
microbial community present as reviewed by Ciferri (1999) Despite this knowledge a
reliable characterization of bacteria associated with such damage is often lacking To
obtain greater insight into the bacterial community involved in biodeterioration of mural
paintings three sites (from the necropolis at Carmona Spain and the Saint-Catherine
chapel of the castle at Herberstein Austria) were sampled In previous studies from these
sites 385 isolates were analysed by fatty acid methyl ester GC and representatives of
different fatty acid clusters were further studied by 16S rRNA gene sequencing
(Heyrman and Swings 2001) Several of these representative strains showed the highest
sequence similarity with members of the genus Arthrobacter (Heyrman et al 2005)
Jimenez and Samson (1981) analysed the microbial flora of a large fresco painted
in the late 1920s in the monastery ldquoSanta Maria de la Rabidardquo (Huelva Spain) exhibiting
two types of deterioration white efflorescence and green-to-black stains
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
28 Review of Literature
Tate and Rebrikova (1990) thought autotrophic nitrifying bacteria to be the first colonisers
of damaged frescoes and building materials in the cathedral of the nativity of the Virgin in
the Pafnutii-Borovskii monastery (Russia) The bulk of research on biodeterioration of
mural paintings has focused on explaining the observed phenomena by analysing the
microflora present Following this approach a precise characterisation of the
microorganisms using a polyphasic approach was never the first goal
Only a few studies included genomic fingerprinting (16S rDNA sequence analysis)
for the characterisation of bacteria associated with damage on mural paintings
[Rolleke (1996) Pinar et al (2001)] Previous studies based on culture-dependent
techniques showed that the flora present on frescos are fungi (predominant species of
Penicillium Aspergillus Cladosporium and Engyodontium) (Guglielminetti et al 1994)
bacteria (predominant species of Bacillus Arthrobacter Micrococcus Streptomyces and
Pseudomonas) (Heyrman et al 1999) cyanobacteria and eukaryotic algae (species of
Nostoc Lyngbya and Chlorophyceae) (Arino et al 1996 Calvo et al 1993) The killing
effect of an antimicrobial agent on a microorganism can be assessed in several ways
(1) Lethal activity may be expressed as the rate of killing by a fixed concentration
of drug under controlled conditions This rate is determined by measuring the number of
viable bacteria at various time intervals The resulting graphic depiction is known as the
time-kill curve Bacterial killing rates are in part dependent on the class of antibiotic and
the concentration of this agent With certain classes of antibiotics (eg aminoglycosides
and fluoroquino-lones) the rate of killing increases with increased drug concentrations up
to a point of maximum effect This is termed concentration-dependent bactericidal activity
In contrast the killing rates of szlig-lactam agents and vancomycin are relatively slow and
continue only as long as the concentrations are in excess of the MIC This rate of killing is
termed time-dependent bactericidal activity
(2) The minimal concentration of drug needed to kill most of the viable organisms
after incubation for a fixed length of time (generally 24 hours) under a given set of
conditions is the most common estimation of bactericidal activity and is known as either
the minimal bactericidal concentration (MBC) or the minimal lethal concentration (MLC)
It will be referred to in this document as the MBC Unfortunately the definition of the
MBC (999 killing of the final inoculum) is somewhat arbitrary and separates the
bacteria into two populations ndash a segrega-tion which might not have biological relevance
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
29 Review of Literature
The determination of the MBC moreover is so subject to methodologic variables that the
clinical relevance of MBCs is nearly impossible to assess particularly for certain pathogen
and drug combinations (eg Staphylococci and beta-lactam agents)
(3) The serum of a patient receiving an antibiotic may be tested against the
infecting microorganism This can be done using time-kill curve methodology (ie serum
bactericidal rate) or using dilution methodology (ie serum bactericidal titer) The
principles of these methods as well as the influence of biological and technical factors are
similar (Barry et al 1999)
213 Microbial flora associated with deteriorated mural paintings
A great deal of research has been done in this field mainly by using cultivation dependent
methods However by using culture-dependent methods only a very small proportion of
microorganisms can be obtained Far less than 1 of organisms in the environment can be
cultivated by standard cultivation techniques (Pace 1996) Recent studies have shown that
culture-dependent techniques yielded mainly sporeforming bacteria suggesting that plating
leads to an over estimation of the number of spore-forming bacteria A wide number of
investigations have shown that in addition to chemical and physical processes
microorganisms play a major role in degradation of objects of art such as paintings stone-
works wood paper masonry leather parchment glass and metal (Ripka 2005)
A) Bacteria
In general growth of diverse organisms on mural paintings is supported by
humidity slight alkaline pH values and the presence of organic and inorganic nutrient
sources (Weirich 1989) In mural paintings pigments are suspended in water or oil often
binders such as casein and milk are used and they are supplied on the damp lime plaster
(Ciferri 1999) The calcium carbonate formed on contact with air consolidates the
pigments Thus frescos contain mainly inorganic components While chemoautotrophic
nitrifiers and thiobacilli obtain their energy for growth by oxidizing ammonium and
reducing sulphur-compounds respectively heterotrophic bacteria and fungi depend on
organically bound carbon [Tate et al (1991) Lazar (1971) Petushkova et al (1986)
Jimenez et al (1981)] Thus primary colonization of photoautotrophic Cyanobacteria
chemolithoautotrophic nitrifying bacteria and sulphuric acid producing thiobacilli represent
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
30 Review of Literature
the first supply of organic matter The death and lysis of such bacteria promotes the
secondary settlement of heterotrophic bacteria and fungal populations (Calvo et al 1991)
Bacteria may derive from plants or pollen as many sequences obtained in this study
gave high score similarities with bacteria isolated from plants like Moraxella osloensis
Enterobacter cloace Enterobacter agglomerans and Pantoea endophytica Bacteria may
also derive from animal faeces like flies Bacillus Pseudomonas Aeromonas and Panteoa
(Ripka 2005) As Lazar and Dumitru (1973) reported studying mural paintings in a
Romanian monastery the genera Bacillus Arthrobacter and Pseudomonas have been
proved to produce salt efflorescences and were even considered to cause the blanching
phenomenon of frescoes (Jimenez et al 2000) Predominant bacterial genera are Bacillus
Streptomyces Arthrobacter Micrococcus and Pseudomonas [Weirich (1989)
Tate et al (1990) Arroyo et al (1997) Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
B) Fungi
It may be concluded that there is wide variety of fungal forms present on mural
paintings but Aspergillus and Alternaria were found dominating from all the experimental
sites next to them were Cladosporium Drechestera Fusarium Curvularia Chaetomium
Memnoniella Mycelia sterelai Pencillium Emericella Stachybotrytis Trichoderma
Phoma Monodictys Humicola and Epicoccum (Garg et al 1995)
The fungal genera most commonly found in lists of isolated taxa given in literature
are Alternaria Aspergillus Chaetomium Cladosporium Fusarium Penicillium and
Verticullum [Weirich (1989) Tate et al (1990) Guglielminetti et al (1994)
Garg et al (1995) Berner et al (1997) Ciferri (1999)] Some fungi having hard fruiting
bodies represented by sclerotia pycnidia perithecia cleistothecia and stroma could
organize themselves inside the painted layer Many fungal forms having such structures
were identified from our experimental sites viz Emericella nidulans A flavus
Chaetomium sp and Phoma sp etc These structures with little increase in humidity may
cause swelling in the paint film (Garg 1995)
Strains of species of Alternaria and Cladosporium both of them identified on the
mural paintings of the Palace of Schoumlnbrunn are the most common genera isolated from
stone and mural paintings in indoor environments with standard cultivation methods
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
31 Review of Literature
(Ventosa 2004) Saprophytic species of the genus Cladosporium are among the most
abundant fungi isolated in saltern samples Commonly isolated Cyanobacteria belong to
Nostoc and eukaryotic algae to Lyngbya and members of the Chlorophyceae such as
Chlorella Pseudococcomyxa and Pseudopleurococcus [Gorbushina et al (1987)
Calvo et al (1993) Arino et al (1996)]
They grow optimally on media with low water activity due to high salt or sugar
concentrations seem to propagate 70 vegetatively in the salterns and are thus
halotolerantosmotolerant species rather than simple flush-through occurrences
Cladiosporum herbarum was frequently isolated from hypersaline waters dead and dying
plant material air soil food fruit cereals paint and textiles (Ventosa 2004)
C) Algae
Most of the painted areas in temperature climate became covered with green algae
(Pleurococcus Protococcus and Trentopholia) while under tropical conditions blue green
algae of the genera Oscillatoria and Sytonema predominated (Garg 1995) The main
factors which contribute to the growth of algae on wall paintings are the presence of
moisture in the plaster as well as availability of visible light These conditions are quite
prevalent in the tropical climate but in temperature regions also algal growth on wall
paintings have been reported [Tonolo et al (1961) Pietrini et al (1991)]
D) Actinomycetes
Usually literature refers to specific aspects eg the occurrence of cyanobacteria
and algae in caves with natural openings to sunlight or those with artificial lighting fungi
and so forth Actinomycetes have been considered to be mainly confined to soils where
they find their natural habitat but despite intensive studies there are still many gaps in our
knowledge of the role played by actinomycetes in soil processes and biodegrations of
murals cave paintings (Groth et al 1999) In addition halophilic bacteria actinomycetes
and cyanobacteria are also capable of growing on salt-affected mural paintings
(Karbowska 2003)
Monte and Ferrari (1993) reviewed the mechanisms of biodeterioration in tombs
and underground churches The role of actinomycetes in the deterioration of frescoes in
hypogean environments was stressed by Agarossi et al (1985) Monte and Ferrari (1993)
Giacobini et al (1987) described the serious damage suffered by a whole series of famous
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
32 Review of Literature
frescoes in underground environments Actinomycetes were isolated from these mural
paintings located in crypts caves and tombs About 200 strains of actinomycetes were
isolated 60 of which were identified The most frequent species were Streptomyces albus
S cinereoruber S griseolus S vinaceus and some members of the Nocardia genus
Heterotrophic bacteria and actinomycetes were the most abundant microorganisms
on the frescoes of Etruscan tombs (Agarossi et al 1985) Bettini et al (1977) studied
some of the oldest Etruscan tombs (7th to 4th century BC) and found white-grey patinas
and spots from streptomycetes in the mural paintings They related the biodeterioration to
the microclimatic conditions (eg lower temperatures high RH) Monte and Ferrari (1993)
considered that colonization of the mural paintings was the result of selective competitive
and inhibitory dynamics among different microorganisms under different and changing
environmental conditions The pigments excreted by some actinomycetes were responsible
for the violet stains found on the walls of tombs in Tarquinia Similar stains were observed
in one of the Roman tombs the Circular Mausoleum the Necropolis of Carmona Spain
from which a Streptomyces sp producing violet pigments in culture media was isolated
214 Identification of biodeteriogens
The possibility of pigments and biodeteriogens identification in frescos and stone
monitoring is offered mostly by vibrational spectroscopy infrared thermography laser
induced fluorescence (LIF) laser induced breakdown spectroscopy (LIBS) XRF (X-Ray
Fluorescence) IR and UV emission Among them laser based methods allowing for in
situ or remote characterization of artwork surface were applied successfully for
prospecting diagnosis and maintenance (Colao et al 2005) The rep-PCR fingerprinting
of the isolates allowed determination of their genotypic diversity Studies that have
compared rep-PCR genomic fingerprint analysis with DNAndashDNA relatedness studies have
shown that the two techniques yield results that are in close agreement [Nick et al (1999)
Rademaker et al (2000)] These studies therefore suggest that rep-PCR fingerprinting can
be used as a genomic screening method to differentiate at the species level and to select
representatives for DNAndashDNA reassociation experiments (Heymann et al 2003)
The characterisation of bacteria was for example often limited to isolation from
group-specific media followed by microscopy [Sorlini et al (1987) Weirich (1989)
Tate et al (1990) and in more recent studies to morphological and physiological
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
33 Review of Literature
characteristics including miniaturised and automated systems such as API and BIOLOG
[Arroyo et al (1997) Jimmenez et al (2000) and Laiz et al (2000)] or to
chemotaxonomic characteristics [Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
Wagner et al (1994) demonstrated that conventional microbiological efforts can
fail to isolate all microorganisms present in natural samples DNA-based techniques used
to identify microorganisms have revealed only a smaller fraction of bacteria isolated from
artworks (Ward et al 1990 Rolleke et al 1996) Bacterial identification using molecular
techniques especially those including the sequencing of genes coding for ribosomal
16S rRNA is very important to study bacterial communities found on artefacts One such
method is Denaturing Gradient Gel Electrophoresis (DGGE) of PCR-amplified gene
fragments coding for rRNA (Muyzer et al 1993) that allows the separation of partial
16S rDNA amplified fragments of identical length but different sequence due to their
different melting behaviour in a gel system containing a gradient of denaturants
(Jimenez 2003)
Total genomic DNA was purified for 16S rRNA gene sequencing and rep-PCR
using a slight modification of the method of Pitcher et al (1989) as described by
Heyndrickx et al (1996) rep-PCR genomic fingerprinting was performed with the REP-
and (GTG)5 primers (Versalovic et al 1994) using the PCR conditions described
previously by Rademaker et al (1997) Electrophoresis and pattern analysis were further
performed as described by Heyrman et al (2003) 16S rRNA gene sequencing and
phylogenetic analysis were performed as described by Heyrman and Swings (2001)
Phylogenetic trees were constructed using the BioNumerics software (Applied Maths) by
applying the neighbour-joining and maximum-parsimony methods on a multiple alignment
similarity matrix The stability of relationships was assessed by a bootstrap analysis of
1000 datasets For determination of the G+C content and levels of DNAndashDNA
hybridization approximately 1 g biomass was harvested from agar plates DNA was
purified by using a combination of the protocols of Marmur (1961) and
Pitcher et al (1989) as described by Logan et al (2000) The G+C content of the DNA
was determined by HPLC (Mesbah et al 1989) using the further specifications given by
Logan et al (2000) DNAndashDNA hybridization experiments were performed using a
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
34 Review of Literature
modification of the microplate method of Ezaki et al (1989) as described by
Willems et al (2001)
215 Preservation and conservation
Nowadays the conservation and preservation of our cultural heritage is one of the
world main concerns particularly in Europe The increasing need for non-destructive
investigation tools has become a major issue as sampling is in most cases restricted in
view of the value or the uniqueness of the object Artworks as wall paintings in buildings
and monuments of historical interest are affected by environment physical (temperature
and humidity) and biological factors (biodeteriogens) and by human (pollutant releases)
impact and therefore modified over the time The term ldquoconservationrdquo may have many
different meanings in different fields Every intervention directed to the restoration and
safeguard of works of art is commonly considered as a conservation treatment For
example conservation can involve the cleaning procedures set up by chemists or the photo
documentation of the preservation of historical memory For the appropriate conservation
of works of art even the lighting systems in a museum or the control of the visitorrsquos
movements in a site should be monitored Chemical degradation which induces the flaking
of paintings and deterioration from rain wind dust and other environmental causes is
mainly responsible for the weakening of the porous structure and the surface layers of the
materials used in works of cultural heritage (Colao et al 2005)
216 Conservation history
Wall paintings are an integral part of monuments and sites and should be preserved
in situ Many of the problems affecting wall paintings are linked to the poor condition of
the building or structure its improper use lack of maintenance frequent repairs and
alterations Also frequent restorations unnecessary uncovering and use of inappropriate
methods and materials can result in irreparable damage Substandard and inadequate
practices and professional qualifications have led to unfortunate results It is for this reason
that an appropriate document covering the principles of proper conservation-restoration of
wall paintings is necessary
The Venice Charter (1964) has provided general principles for the conservation-
restoration of cultural heritage The Amsterdam Declaration (1975) introducing the
concept of integrated conservation and the Nara Document on Authenticity (1994) dealing
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
35 Review of Literature
with cultural diversity have expanded these principles Taking into account these and
additional relevant contributions such as the ICOM-CC Code of Ethics (1984) Document
of Pavia (1997) and ECCO Professional Guidelines (1997) the aim of this document is
to provide more specific principles for the protection preservation and the conservation
restoration of wall paintings This document therefore reflects basic and universally
applicable principles and practices and does not take into account particular problems of
regions or countries which can be supplemented at regional and national level by
providing further recommendations where necessary
217 Preservation techniques of the mural paintings
The removal of fat salts varnishes and pollutants from the surfaces of the works
of art are mostly done by chemical and mechanical methods At the end of the 19th
century the practices of restoration methods that do not inhibit further future interventions
was considered acceptable During the 1960s several chemicals such as polymeric resins
were synthesized and applied as a consolidation or protection agents The accepted idea
was that these substances could be removed at any time leaving a completely unaltered
substrate On the basis of origin archaeological objects can be classified as follows
(Carretti 2005)
1 Inorganic It includes siliceous and nonsiliceous materials Archaeological materials
produced from stones terracotta ceramics and glass can be included under siliceous
materials whereas objects made of metals can be included under nonsiliceous inorganic
materials Again metal objects can be classified as ferrous metals and non-ferrous metals
Objects made of iron are termed as ferrous metal objects whereas metal objects made from
other than iron is termed as non-ferrous metal objects
2 Organic It includes archival and anthropological materials Again archival materials
include paper bhojapatra tadapatra textiles wooden objects miniature paintings whereas
anthropological objects include bone and ivory leather feather and fur etc
In the past restoration of paintings and other old artwork often involved application
of acrylic resins to consolidate and protect them One of the most important tasks for
modern restorers is thus to remove these layers because it turns out that acrylic resins not
only by drastically changing the optics of the treated artwork but in many cases they
accelerate their degradation The scientists use an oil-in-water microemulsion with the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
36 Review of Literature
organic solvent para-xylene as the oil component The matrix makes the cleaning agent
viscous so that it cannot enter very far into the pores of a painting (Carretti 2005)
Nanoparticle treatment is the logical evolution of the Ferroni-Dini method
Dispersions of kinetically stable Ca (OH)2 nanoparticles in non-aqueous solvents solved
most of the drawbacks of the microsized powders Stable dispersions of calcium hydroxide
have been successfully applied (replacing polymers) as fixatives to re-adhere lifted paint
layers during many restoration workshops in Italy and in Europe as a consolidant The
FerronindashDini method (two steps the application of a saturated solution of ammonium
carbonate (NH4)2CO3 and the treatment with a barium hydroxide solution Ba(OH)2 also
called the barium method has long been the acknowledged method for the removal of
salts that threaten paintings reinforcing at the same time the porous structure However
commercially available carbonates and hydroxide powders have dimensions of several
micrometres much larger than the pores on the paint surface This means they donrsquot
penetrate the painting well and there is also a risk of damaging the artwork by a white
glaze forming on the surface (Berger 2006) Restoration should provide the reinforcement
of the porous structure and the consolidation of the surface layer of arte facts A few
simple principles can be considered to define the most appropriate restoration method
1) The treatment should be reversible so that one can revert to the original status of the
work of art at any desired time
2) All the applied chemicals must ensure the maximum durability and the chemical
inertness
3) The applied chemicals must invert the degradation processes without altering the
chemical composition of the artefacts and their physico-chemical and mechanical
properties (Baglioni 2006)
218 Commercial preservative used for preservation of mural paintings
Cleaning was done using soft brushes vacuum cleaner and Gumma paine (dough)
a natural latex sponge Areas near the window were very dirty with black soot and were
cleaned with micro fibrous cloths moistened with synperonic N (surfactant alkyl phenol
ethoxylate based on nonyl phenol) and neutralized with clean water In several places the
paint layers had separated from the substrate (exfoli-ation) In that cases loose paint flakes
were stuck back using Paraloid B72 (10 solution in ethanol) as sparingly as possible
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
37 Review of Literature
Paraloid was injected with syringe behind the exfoliated area twice pushed and held back
with Melinex (polyester film) until fixed on the third application (Bionda et al 2002)
In a period of significant growth of molds and intensive efforts to stop the mold
contamination some of the lines of certain paintings were obscured or faded Solutions of
ethanol formalin 91 and Thiabendazole (TBZ) were used but they were not very
effective Para-formaldehyde fumigation was adopted beginning in 1981 to establish an
emergency treatment sensitivity of microorganisms from studied samples was tested
against Desogen by adding 1-3 (v v) in serial dilutions The best concentration
3 (vv) was applied with a brush to prevent spreading of the spores In order to overcome
the problem of fungal attack suitable fungicides carbendizeme or kiroxy-I or 5 solute of
N formaldehyde can be used Shellac solution in spirit or 2 solution of polyvinaycletate
in toluene can be used as preservative and consolidantsTo control insect and fungal attack
fumigants like pyrethrum DDT or 5 solution of sodium penta chlorophenate in kerosene
oil 2 to 5 solution of PVA in toluene or 2 to 5 solution of paraloid B-72 in toluene or
acetone be used (Miura 2009) Microclimatic conditions constitute a critical factor in the
conservation of cave paintings The unstable microclimatic condition is one of the factors
that always affect the state of conservation of mural paintings In the environmental-
monument system knowledge of the functional environment and climatic conditions of the
surroundings are necessary for the identification of causes of decay (Singh 2011)
Furthermore the risk of formation of indoor bioaerosols in residential and public
buildings (offices schools museums etc) has attracted interest in the last years due to
socio-economic as well as sanitary reasons (Ripka 2005) Thus it is important in aspects of
health and maintenance of Cultural Heritage to analyse the complete microflora to further
develop biocides for harmful microorganisms and methods for restoration of damaged
objects of art The biocidal testing was carried out on one representative algal species of
the two classes of algae viz Chlorococcum sp (green) and Chroococcus sp (blue-green)
found to be common in all the samples Efficiency tests were carried out both in liquid as
well as solid media containing algal suspensions by adding a biocide solution of known
concentration and determining the growth of the microorganism after the incubation
period The biocides used for the past studies were
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
26 Review of Literature
211 Types of deterioration on mural paintings
The frescos represent a variety of ecological niches where primary colonization is
due to photoautotrophic and chemolithoautotrophic microorganisms followed by
secondary colonization due to heterotrophic bacteria that obtain nutrients from various
sources (metabolites of autotrophic bacteria airborne organic contamination animal faeces
and organic compounds in the paint layers themselves) Microbial-induced deterioration
processes cause structural as well as aesthetic damage to wall paintings such as the
discoloration of materials the formation of crusts on surfaces and the loss of material
(Sarro et al 2006 Osburn et al 2011) Halophilic bacteria and archaea were thought to
be found only in extreme environments like salt lakes or black smokers However it has
been shown that mural paintings and stones are a common habitat for extremely salt
tolerant and moderate halophilic (Ripka 2005) Microbial induced deterioration processes
can cause different kinds of alterations such as discolouration of materials the formation of
crusts on surfaces and the loss of material which leads to structural damage (Ripka 2005)
First of all microorganisms can cause severe problems due to the excretion of aggressive
metabolic products such as organic or inorganic acids Secondly material components can
be used as substrates for microbial metabolism Exoenzymes such as cellulases proteases
tannases beta-glucosidase produced by fungi and bacteria are responsible for hydrolysis of
cellulose and proteins Further examples are mechanical processes caused by swelling and
shrinking of slime or mycelia penetrating inside plaster of the painting resulting in loss of
cohesion and detachment of the paint layer (Rolleke 1996 Gurtner et al 2000)
Table-21 Microbial damage on mural paintings (Rolleke 1996)
S No Damage Microbial activity
1 Green brown red grey
surface layers (patinas)
Pigments produced by microorganisms (intra-or
extracellular) as chlorophyll and carotinoids
2 Dislodging of painting layers Use of organic binders as nutrient and energy
source
3 Acid attack of carbonates Acid produced by fungi or bacteria
4 Discolouration of pigments Redox-reactions induced by fungi and
bacteria
5 Loss of paint layer Growth of microorganisms deep into the plaster
6 Hydrolysis of synthetic
polymers Chemoorganotrophic activity of bacteria and fungi
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
27 Review of Literature
Discolorations are caused by excretion of pigments and microbiologically induced
reductionoxidation-processes (Krumbein et al 1990) Degradation of the bindings is
followed by reduction of stability Oxidation of ammonium and reduced sulphur
compounds results in acidification of the environment such as Sulphuric acid and the
variety of organic acids produced by the heterotrophs cause solubilization of calcareous
binding material and chelation of metal ions (Bock et al 1993) It is now well recognised
that wall paintings can be deteriorated by microorganisms (Ciferri 1999)The growth of
microorganisms essentially results in two types of damage aesthetic and structural
Aesthetic damage implies pigment discoloration stains and formation of a biofilm on the
painted surface Structural damage is observed as cracking and disintegration of the paint
layer formation of paint blisters and degradation of support polymers or of glues and
binders resulting in detachment of paint layer from the support The colonization of mural
paintings by bacteria and other microorganisms can have different causes Provided that
favorable environmental conditions occur nutrients for heterotrophic bacteria and fungi
can be available from metabolites of autotrophic bacteria from airborne contamination and
dripping water from animal faeces but also from organic compounds in the paint layer
itself
212 Methods of studying biodeterioration
It is now well recognized that wall paintings may be deteriorated by
microorganisms as established by several studies that linked the observed damage with the
microbial community present as reviewed by Ciferri (1999) Despite this knowledge a
reliable characterization of bacteria associated with such damage is often lacking To
obtain greater insight into the bacterial community involved in biodeterioration of mural
paintings three sites (from the necropolis at Carmona Spain and the Saint-Catherine
chapel of the castle at Herberstein Austria) were sampled In previous studies from these
sites 385 isolates were analysed by fatty acid methyl ester GC and representatives of
different fatty acid clusters were further studied by 16S rRNA gene sequencing
(Heyrman and Swings 2001) Several of these representative strains showed the highest
sequence similarity with members of the genus Arthrobacter (Heyrman et al 2005)
Jimenez and Samson (1981) analysed the microbial flora of a large fresco painted
in the late 1920s in the monastery ldquoSanta Maria de la Rabidardquo (Huelva Spain) exhibiting
two types of deterioration white efflorescence and green-to-black stains
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
28 Review of Literature
Tate and Rebrikova (1990) thought autotrophic nitrifying bacteria to be the first colonisers
of damaged frescoes and building materials in the cathedral of the nativity of the Virgin in
the Pafnutii-Borovskii monastery (Russia) The bulk of research on biodeterioration of
mural paintings has focused on explaining the observed phenomena by analysing the
microflora present Following this approach a precise characterisation of the
microorganisms using a polyphasic approach was never the first goal
Only a few studies included genomic fingerprinting (16S rDNA sequence analysis)
for the characterisation of bacteria associated with damage on mural paintings
[Rolleke (1996) Pinar et al (2001)] Previous studies based on culture-dependent
techniques showed that the flora present on frescos are fungi (predominant species of
Penicillium Aspergillus Cladosporium and Engyodontium) (Guglielminetti et al 1994)
bacteria (predominant species of Bacillus Arthrobacter Micrococcus Streptomyces and
Pseudomonas) (Heyrman et al 1999) cyanobacteria and eukaryotic algae (species of
Nostoc Lyngbya and Chlorophyceae) (Arino et al 1996 Calvo et al 1993) The killing
effect of an antimicrobial agent on a microorganism can be assessed in several ways
(1) Lethal activity may be expressed as the rate of killing by a fixed concentration
of drug under controlled conditions This rate is determined by measuring the number of
viable bacteria at various time intervals The resulting graphic depiction is known as the
time-kill curve Bacterial killing rates are in part dependent on the class of antibiotic and
the concentration of this agent With certain classes of antibiotics (eg aminoglycosides
and fluoroquino-lones) the rate of killing increases with increased drug concentrations up
to a point of maximum effect This is termed concentration-dependent bactericidal activity
In contrast the killing rates of szlig-lactam agents and vancomycin are relatively slow and
continue only as long as the concentrations are in excess of the MIC This rate of killing is
termed time-dependent bactericidal activity
(2) The minimal concentration of drug needed to kill most of the viable organisms
after incubation for a fixed length of time (generally 24 hours) under a given set of
conditions is the most common estimation of bactericidal activity and is known as either
the minimal bactericidal concentration (MBC) or the minimal lethal concentration (MLC)
It will be referred to in this document as the MBC Unfortunately the definition of the
MBC (999 killing of the final inoculum) is somewhat arbitrary and separates the
bacteria into two populations ndash a segrega-tion which might not have biological relevance
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
29 Review of Literature
The determination of the MBC moreover is so subject to methodologic variables that the
clinical relevance of MBCs is nearly impossible to assess particularly for certain pathogen
and drug combinations (eg Staphylococci and beta-lactam agents)
(3) The serum of a patient receiving an antibiotic may be tested against the
infecting microorganism This can be done using time-kill curve methodology (ie serum
bactericidal rate) or using dilution methodology (ie serum bactericidal titer) The
principles of these methods as well as the influence of biological and technical factors are
similar (Barry et al 1999)
213 Microbial flora associated with deteriorated mural paintings
A great deal of research has been done in this field mainly by using cultivation dependent
methods However by using culture-dependent methods only a very small proportion of
microorganisms can be obtained Far less than 1 of organisms in the environment can be
cultivated by standard cultivation techniques (Pace 1996) Recent studies have shown that
culture-dependent techniques yielded mainly sporeforming bacteria suggesting that plating
leads to an over estimation of the number of spore-forming bacteria A wide number of
investigations have shown that in addition to chemical and physical processes
microorganisms play a major role in degradation of objects of art such as paintings stone-
works wood paper masonry leather parchment glass and metal (Ripka 2005)
A) Bacteria
In general growth of diverse organisms on mural paintings is supported by
humidity slight alkaline pH values and the presence of organic and inorganic nutrient
sources (Weirich 1989) In mural paintings pigments are suspended in water or oil often
binders such as casein and milk are used and they are supplied on the damp lime plaster
(Ciferri 1999) The calcium carbonate formed on contact with air consolidates the
pigments Thus frescos contain mainly inorganic components While chemoautotrophic
nitrifiers and thiobacilli obtain their energy for growth by oxidizing ammonium and
reducing sulphur-compounds respectively heterotrophic bacteria and fungi depend on
organically bound carbon [Tate et al (1991) Lazar (1971) Petushkova et al (1986)
Jimenez et al (1981)] Thus primary colonization of photoautotrophic Cyanobacteria
chemolithoautotrophic nitrifying bacteria and sulphuric acid producing thiobacilli represent
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
30 Review of Literature
the first supply of organic matter The death and lysis of such bacteria promotes the
secondary settlement of heterotrophic bacteria and fungal populations (Calvo et al 1991)
Bacteria may derive from plants or pollen as many sequences obtained in this study
gave high score similarities with bacteria isolated from plants like Moraxella osloensis
Enterobacter cloace Enterobacter agglomerans and Pantoea endophytica Bacteria may
also derive from animal faeces like flies Bacillus Pseudomonas Aeromonas and Panteoa
(Ripka 2005) As Lazar and Dumitru (1973) reported studying mural paintings in a
Romanian monastery the genera Bacillus Arthrobacter and Pseudomonas have been
proved to produce salt efflorescences and were even considered to cause the blanching
phenomenon of frescoes (Jimenez et al 2000) Predominant bacterial genera are Bacillus
Streptomyces Arthrobacter Micrococcus and Pseudomonas [Weirich (1989)
Tate et al (1990) Arroyo et al (1997) Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
B) Fungi
It may be concluded that there is wide variety of fungal forms present on mural
paintings but Aspergillus and Alternaria were found dominating from all the experimental
sites next to them were Cladosporium Drechestera Fusarium Curvularia Chaetomium
Memnoniella Mycelia sterelai Pencillium Emericella Stachybotrytis Trichoderma
Phoma Monodictys Humicola and Epicoccum (Garg et al 1995)
The fungal genera most commonly found in lists of isolated taxa given in literature
are Alternaria Aspergillus Chaetomium Cladosporium Fusarium Penicillium and
Verticullum [Weirich (1989) Tate et al (1990) Guglielminetti et al (1994)
Garg et al (1995) Berner et al (1997) Ciferri (1999)] Some fungi having hard fruiting
bodies represented by sclerotia pycnidia perithecia cleistothecia and stroma could
organize themselves inside the painted layer Many fungal forms having such structures
were identified from our experimental sites viz Emericella nidulans A flavus
Chaetomium sp and Phoma sp etc These structures with little increase in humidity may
cause swelling in the paint film (Garg 1995)
Strains of species of Alternaria and Cladosporium both of them identified on the
mural paintings of the Palace of Schoumlnbrunn are the most common genera isolated from
stone and mural paintings in indoor environments with standard cultivation methods
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
31 Review of Literature
(Ventosa 2004) Saprophytic species of the genus Cladosporium are among the most
abundant fungi isolated in saltern samples Commonly isolated Cyanobacteria belong to
Nostoc and eukaryotic algae to Lyngbya and members of the Chlorophyceae such as
Chlorella Pseudococcomyxa and Pseudopleurococcus [Gorbushina et al (1987)
Calvo et al (1993) Arino et al (1996)]
They grow optimally on media with low water activity due to high salt or sugar
concentrations seem to propagate 70 vegetatively in the salterns and are thus
halotolerantosmotolerant species rather than simple flush-through occurrences
Cladiosporum herbarum was frequently isolated from hypersaline waters dead and dying
plant material air soil food fruit cereals paint and textiles (Ventosa 2004)
C) Algae
Most of the painted areas in temperature climate became covered with green algae
(Pleurococcus Protococcus and Trentopholia) while under tropical conditions blue green
algae of the genera Oscillatoria and Sytonema predominated (Garg 1995) The main
factors which contribute to the growth of algae on wall paintings are the presence of
moisture in the plaster as well as availability of visible light These conditions are quite
prevalent in the tropical climate but in temperature regions also algal growth on wall
paintings have been reported [Tonolo et al (1961) Pietrini et al (1991)]
D) Actinomycetes
Usually literature refers to specific aspects eg the occurrence of cyanobacteria
and algae in caves with natural openings to sunlight or those with artificial lighting fungi
and so forth Actinomycetes have been considered to be mainly confined to soils where
they find their natural habitat but despite intensive studies there are still many gaps in our
knowledge of the role played by actinomycetes in soil processes and biodegrations of
murals cave paintings (Groth et al 1999) In addition halophilic bacteria actinomycetes
and cyanobacteria are also capable of growing on salt-affected mural paintings
(Karbowska 2003)
Monte and Ferrari (1993) reviewed the mechanisms of biodeterioration in tombs
and underground churches The role of actinomycetes in the deterioration of frescoes in
hypogean environments was stressed by Agarossi et al (1985) Monte and Ferrari (1993)
Giacobini et al (1987) described the serious damage suffered by a whole series of famous
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
32 Review of Literature
frescoes in underground environments Actinomycetes were isolated from these mural
paintings located in crypts caves and tombs About 200 strains of actinomycetes were
isolated 60 of which were identified The most frequent species were Streptomyces albus
S cinereoruber S griseolus S vinaceus and some members of the Nocardia genus
Heterotrophic bacteria and actinomycetes were the most abundant microorganisms
on the frescoes of Etruscan tombs (Agarossi et al 1985) Bettini et al (1977) studied
some of the oldest Etruscan tombs (7th to 4th century BC) and found white-grey patinas
and spots from streptomycetes in the mural paintings They related the biodeterioration to
the microclimatic conditions (eg lower temperatures high RH) Monte and Ferrari (1993)
considered that colonization of the mural paintings was the result of selective competitive
and inhibitory dynamics among different microorganisms under different and changing
environmental conditions The pigments excreted by some actinomycetes were responsible
for the violet stains found on the walls of tombs in Tarquinia Similar stains were observed
in one of the Roman tombs the Circular Mausoleum the Necropolis of Carmona Spain
from which a Streptomyces sp producing violet pigments in culture media was isolated
214 Identification of biodeteriogens
The possibility of pigments and biodeteriogens identification in frescos and stone
monitoring is offered mostly by vibrational spectroscopy infrared thermography laser
induced fluorescence (LIF) laser induced breakdown spectroscopy (LIBS) XRF (X-Ray
Fluorescence) IR and UV emission Among them laser based methods allowing for in
situ or remote characterization of artwork surface were applied successfully for
prospecting diagnosis and maintenance (Colao et al 2005) The rep-PCR fingerprinting
of the isolates allowed determination of their genotypic diversity Studies that have
compared rep-PCR genomic fingerprint analysis with DNAndashDNA relatedness studies have
shown that the two techniques yield results that are in close agreement [Nick et al (1999)
Rademaker et al (2000)] These studies therefore suggest that rep-PCR fingerprinting can
be used as a genomic screening method to differentiate at the species level and to select
representatives for DNAndashDNA reassociation experiments (Heymann et al 2003)
The characterisation of bacteria was for example often limited to isolation from
group-specific media followed by microscopy [Sorlini et al (1987) Weirich (1989)
Tate et al (1990) and in more recent studies to morphological and physiological
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
33 Review of Literature
characteristics including miniaturised and automated systems such as API and BIOLOG
[Arroyo et al (1997) Jimmenez et al (2000) and Laiz et al (2000)] or to
chemotaxonomic characteristics [Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
Wagner et al (1994) demonstrated that conventional microbiological efforts can
fail to isolate all microorganisms present in natural samples DNA-based techniques used
to identify microorganisms have revealed only a smaller fraction of bacteria isolated from
artworks (Ward et al 1990 Rolleke et al 1996) Bacterial identification using molecular
techniques especially those including the sequencing of genes coding for ribosomal
16S rRNA is very important to study bacterial communities found on artefacts One such
method is Denaturing Gradient Gel Electrophoresis (DGGE) of PCR-amplified gene
fragments coding for rRNA (Muyzer et al 1993) that allows the separation of partial
16S rDNA amplified fragments of identical length but different sequence due to their
different melting behaviour in a gel system containing a gradient of denaturants
(Jimenez 2003)
Total genomic DNA was purified for 16S rRNA gene sequencing and rep-PCR
using a slight modification of the method of Pitcher et al (1989) as described by
Heyndrickx et al (1996) rep-PCR genomic fingerprinting was performed with the REP-
and (GTG)5 primers (Versalovic et al 1994) using the PCR conditions described
previously by Rademaker et al (1997) Electrophoresis and pattern analysis were further
performed as described by Heyrman et al (2003) 16S rRNA gene sequencing and
phylogenetic analysis were performed as described by Heyrman and Swings (2001)
Phylogenetic trees were constructed using the BioNumerics software (Applied Maths) by
applying the neighbour-joining and maximum-parsimony methods on a multiple alignment
similarity matrix The stability of relationships was assessed by a bootstrap analysis of
1000 datasets For determination of the G+C content and levels of DNAndashDNA
hybridization approximately 1 g biomass was harvested from agar plates DNA was
purified by using a combination of the protocols of Marmur (1961) and
Pitcher et al (1989) as described by Logan et al (2000) The G+C content of the DNA
was determined by HPLC (Mesbah et al 1989) using the further specifications given by
Logan et al (2000) DNAndashDNA hybridization experiments were performed using a
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
34 Review of Literature
modification of the microplate method of Ezaki et al (1989) as described by
Willems et al (2001)
215 Preservation and conservation
Nowadays the conservation and preservation of our cultural heritage is one of the
world main concerns particularly in Europe The increasing need for non-destructive
investigation tools has become a major issue as sampling is in most cases restricted in
view of the value or the uniqueness of the object Artworks as wall paintings in buildings
and monuments of historical interest are affected by environment physical (temperature
and humidity) and biological factors (biodeteriogens) and by human (pollutant releases)
impact and therefore modified over the time The term ldquoconservationrdquo may have many
different meanings in different fields Every intervention directed to the restoration and
safeguard of works of art is commonly considered as a conservation treatment For
example conservation can involve the cleaning procedures set up by chemists or the photo
documentation of the preservation of historical memory For the appropriate conservation
of works of art even the lighting systems in a museum or the control of the visitorrsquos
movements in a site should be monitored Chemical degradation which induces the flaking
of paintings and deterioration from rain wind dust and other environmental causes is
mainly responsible for the weakening of the porous structure and the surface layers of the
materials used in works of cultural heritage (Colao et al 2005)
216 Conservation history
Wall paintings are an integral part of monuments and sites and should be preserved
in situ Many of the problems affecting wall paintings are linked to the poor condition of
the building or structure its improper use lack of maintenance frequent repairs and
alterations Also frequent restorations unnecessary uncovering and use of inappropriate
methods and materials can result in irreparable damage Substandard and inadequate
practices and professional qualifications have led to unfortunate results It is for this reason
that an appropriate document covering the principles of proper conservation-restoration of
wall paintings is necessary
The Venice Charter (1964) has provided general principles for the conservation-
restoration of cultural heritage The Amsterdam Declaration (1975) introducing the
concept of integrated conservation and the Nara Document on Authenticity (1994) dealing
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
35 Review of Literature
with cultural diversity have expanded these principles Taking into account these and
additional relevant contributions such as the ICOM-CC Code of Ethics (1984) Document
of Pavia (1997) and ECCO Professional Guidelines (1997) the aim of this document is
to provide more specific principles for the protection preservation and the conservation
restoration of wall paintings This document therefore reflects basic and universally
applicable principles and practices and does not take into account particular problems of
regions or countries which can be supplemented at regional and national level by
providing further recommendations where necessary
217 Preservation techniques of the mural paintings
The removal of fat salts varnishes and pollutants from the surfaces of the works
of art are mostly done by chemical and mechanical methods At the end of the 19th
century the practices of restoration methods that do not inhibit further future interventions
was considered acceptable During the 1960s several chemicals such as polymeric resins
were synthesized and applied as a consolidation or protection agents The accepted idea
was that these substances could be removed at any time leaving a completely unaltered
substrate On the basis of origin archaeological objects can be classified as follows
(Carretti 2005)
1 Inorganic It includes siliceous and nonsiliceous materials Archaeological materials
produced from stones terracotta ceramics and glass can be included under siliceous
materials whereas objects made of metals can be included under nonsiliceous inorganic
materials Again metal objects can be classified as ferrous metals and non-ferrous metals
Objects made of iron are termed as ferrous metal objects whereas metal objects made from
other than iron is termed as non-ferrous metal objects
2 Organic It includes archival and anthropological materials Again archival materials
include paper bhojapatra tadapatra textiles wooden objects miniature paintings whereas
anthropological objects include bone and ivory leather feather and fur etc
In the past restoration of paintings and other old artwork often involved application
of acrylic resins to consolidate and protect them One of the most important tasks for
modern restorers is thus to remove these layers because it turns out that acrylic resins not
only by drastically changing the optics of the treated artwork but in many cases they
accelerate their degradation The scientists use an oil-in-water microemulsion with the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
36 Review of Literature
organic solvent para-xylene as the oil component The matrix makes the cleaning agent
viscous so that it cannot enter very far into the pores of a painting (Carretti 2005)
Nanoparticle treatment is the logical evolution of the Ferroni-Dini method
Dispersions of kinetically stable Ca (OH)2 nanoparticles in non-aqueous solvents solved
most of the drawbacks of the microsized powders Stable dispersions of calcium hydroxide
have been successfully applied (replacing polymers) as fixatives to re-adhere lifted paint
layers during many restoration workshops in Italy and in Europe as a consolidant The
FerronindashDini method (two steps the application of a saturated solution of ammonium
carbonate (NH4)2CO3 and the treatment with a barium hydroxide solution Ba(OH)2 also
called the barium method has long been the acknowledged method for the removal of
salts that threaten paintings reinforcing at the same time the porous structure However
commercially available carbonates and hydroxide powders have dimensions of several
micrometres much larger than the pores on the paint surface This means they donrsquot
penetrate the painting well and there is also a risk of damaging the artwork by a white
glaze forming on the surface (Berger 2006) Restoration should provide the reinforcement
of the porous structure and the consolidation of the surface layer of arte facts A few
simple principles can be considered to define the most appropriate restoration method
1) The treatment should be reversible so that one can revert to the original status of the
work of art at any desired time
2) All the applied chemicals must ensure the maximum durability and the chemical
inertness
3) The applied chemicals must invert the degradation processes without altering the
chemical composition of the artefacts and their physico-chemical and mechanical
properties (Baglioni 2006)
218 Commercial preservative used for preservation of mural paintings
Cleaning was done using soft brushes vacuum cleaner and Gumma paine (dough)
a natural latex sponge Areas near the window were very dirty with black soot and were
cleaned with micro fibrous cloths moistened with synperonic N (surfactant alkyl phenol
ethoxylate based on nonyl phenol) and neutralized with clean water In several places the
paint layers had separated from the substrate (exfoli-ation) In that cases loose paint flakes
were stuck back using Paraloid B72 (10 solution in ethanol) as sparingly as possible
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
37 Review of Literature
Paraloid was injected with syringe behind the exfoliated area twice pushed and held back
with Melinex (polyester film) until fixed on the third application (Bionda et al 2002)
In a period of significant growth of molds and intensive efforts to stop the mold
contamination some of the lines of certain paintings were obscured or faded Solutions of
ethanol formalin 91 and Thiabendazole (TBZ) were used but they were not very
effective Para-formaldehyde fumigation was adopted beginning in 1981 to establish an
emergency treatment sensitivity of microorganisms from studied samples was tested
against Desogen by adding 1-3 (v v) in serial dilutions The best concentration
3 (vv) was applied with a brush to prevent spreading of the spores In order to overcome
the problem of fungal attack suitable fungicides carbendizeme or kiroxy-I or 5 solute of
N formaldehyde can be used Shellac solution in spirit or 2 solution of polyvinaycletate
in toluene can be used as preservative and consolidantsTo control insect and fungal attack
fumigants like pyrethrum DDT or 5 solution of sodium penta chlorophenate in kerosene
oil 2 to 5 solution of PVA in toluene or 2 to 5 solution of paraloid B-72 in toluene or
acetone be used (Miura 2009) Microclimatic conditions constitute a critical factor in the
conservation of cave paintings The unstable microclimatic condition is one of the factors
that always affect the state of conservation of mural paintings In the environmental-
monument system knowledge of the functional environment and climatic conditions of the
surroundings are necessary for the identification of causes of decay (Singh 2011)
Furthermore the risk of formation of indoor bioaerosols in residential and public
buildings (offices schools museums etc) has attracted interest in the last years due to
socio-economic as well as sanitary reasons (Ripka 2005) Thus it is important in aspects of
health and maintenance of Cultural Heritage to analyse the complete microflora to further
develop biocides for harmful microorganisms and methods for restoration of damaged
objects of art The biocidal testing was carried out on one representative algal species of
the two classes of algae viz Chlorococcum sp (green) and Chroococcus sp (blue-green)
found to be common in all the samples Efficiency tests were carried out both in liquid as
well as solid media containing algal suspensions by adding a biocide solution of known
concentration and determining the growth of the microorganism after the incubation
period The biocides used for the past studies were
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
27 Review of Literature
Discolorations are caused by excretion of pigments and microbiologically induced
reductionoxidation-processes (Krumbein et al 1990) Degradation of the bindings is
followed by reduction of stability Oxidation of ammonium and reduced sulphur
compounds results in acidification of the environment such as Sulphuric acid and the
variety of organic acids produced by the heterotrophs cause solubilization of calcareous
binding material and chelation of metal ions (Bock et al 1993) It is now well recognised
that wall paintings can be deteriorated by microorganisms (Ciferri 1999)The growth of
microorganisms essentially results in two types of damage aesthetic and structural
Aesthetic damage implies pigment discoloration stains and formation of a biofilm on the
painted surface Structural damage is observed as cracking and disintegration of the paint
layer formation of paint blisters and degradation of support polymers or of glues and
binders resulting in detachment of paint layer from the support The colonization of mural
paintings by bacteria and other microorganisms can have different causes Provided that
favorable environmental conditions occur nutrients for heterotrophic bacteria and fungi
can be available from metabolites of autotrophic bacteria from airborne contamination and
dripping water from animal faeces but also from organic compounds in the paint layer
itself
212 Methods of studying biodeterioration
It is now well recognized that wall paintings may be deteriorated by
microorganisms as established by several studies that linked the observed damage with the
microbial community present as reviewed by Ciferri (1999) Despite this knowledge a
reliable characterization of bacteria associated with such damage is often lacking To
obtain greater insight into the bacterial community involved in biodeterioration of mural
paintings three sites (from the necropolis at Carmona Spain and the Saint-Catherine
chapel of the castle at Herberstein Austria) were sampled In previous studies from these
sites 385 isolates were analysed by fatty acid methyl ester GC and representatives of
different fatty acid clusters were further studied by 16S rRNA gene sequencing
(Heyrman and Swings 2001) Several of these representative strains showed the highest
sequence similarity with members of the genus Arthrobacter (Heyrman et al 2005)
Jimenez and Samson (1981) analysed the microbial flora of a large fresco painted
in the late 1920s in the monastery ldquoSanta Maria de la Rabidardquo (Huelva Spain) exhibiting
two types of deterioration white efflorescence and green-to-black stains
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
28 Review of Literature
Tate and Rebrikova (1990) thought autotrophic nitrifying bacteria to be the first colonisers
of damaged frescoes and building materials in the cathedral of the nativity of the Virgin in
the Pafnutii-Borovskii monastery (Russia) The bulk of research on biodeterioration of
mural paintings has focused on explaining the observed phenomena by analysing the
microflora present Following this approach a precise characterisation of the
microorganisms using a polyphasic approach was never the first goal
Only a few studies included genomic fingerprinting (16S rDNA sequence analysis)
for the characterisation of bacteria associated with damage on mural paintings
[Rolleke (1996) Pinar et al (2001)] Previous studies based on culture-dependent
techniques showed that the flora present on frescos are fungi (predominant species of
Penicillium Aspergillus Cladosporium and Engyodontium) (Guglielminetti et al 1994)
bacteria (predominant species of Bacillus Arthrobacter Micrococcus Streptomyces and
Pseudomonas) (Heyrman et al 1999) cyanobacteria and eukaryotic algae (species of
Nostoc Lyngbya and Chlorophyceae) (Arino et al 1996 Calvo et al 1993) The killing
effect of an antimicrobial agent on a microorganism can be assessed in several ways
(1) Lethal activity may be expressed as the rate of killing by a fixed concentration
of drug under controlled conditions This rate is determined by measuring the number of
viable bacteria at various time intervals The resulting graphic depiction is known as the
time-kill curve Bacterial killing rates are in part dependent on the class of antibiotic and
the concentration of this agent With certain classes of antibiotics (eg aminoglycosides
and fluoroquino-lones) the rate of killing increases with increased drug concentrations up
to a point of maximum effect This is termed concentration-dependent bactericidal activity
In contrast the killing rates of szlig-lactam agents and vancomycin are relatively slow and
continue only as long as the concentrations are in excess of the MIC This rate of killing is
termed time-dependent bactericidal activity
(2) The minimal concentration of drug needed to kill most of the viable organisms
after incubation for a fixed length of time (generally 24 hours) under a given set of
conditions is the most common estimation of bactericidal activity and is known as either
the minimal bactericidal concentration (MBC) or the minimal lethal concentration (MLC)
It will be referred to in this document as the MBC Unfortunately the definition of the
MBC (999 killing of the final inoculum) is somewhat arbitrary and separates the
bacteria into two populations ndash a segrega-tion which might not have biological relevance
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
29 Review of Literature
The determination of the MBC moreover is so subject to methodologic variables that the
clinical relevance of MBCs is nearly impossible to assess particularly for certain pathogen
and drug combinations (eg Staphylococci and beta-lactam agents)
(3) The serum of a patient receiving an antibiotic may be tested against the
infecting microorganism This can be done using time-kill curve methodology (ie serum
bactericidal rate) or using dilution methodology (ie serum bactericidal titer) The
principles of these methods as well as the influence of biological and technical factors are
similar (Barry et al 1999)
213 Microbial flora associated with deteriorated mural paintings
A great deal of research has been done in this field mainly by using cultivation dependent
methods However by using culture-dependent methods only a very small proportion of
microorganisms can be obtained Far less than 1 of organisms in the environment can be
cultivated by standard cultivation techniques (Pace 1996) Recent studies have shown that
culture-dependent techniques yielded mainly sporeforming bacteria suggesting that plating
leads to an over estimation of the number of spore-forming bacteria A wide number of
investigations have shown that in addition to chemical and physical processes
microorganisms play a major role in degradation of objects of art such as paintings stone-
works wood paper masonry leather parchment glass and metal (Ripka 2005)
A) Bacteria
In general growth of diverse organisms on mural paintings is supported by
humidity slight alkaline pH values and the presence of organic and inorganic nutrient
sources (Weirich 1989) In mural paintings pigments are suspended in water or oil often
binders such as casein and milk are used and they are supplied on the damp lime plaster
(Ciferri 1999) The calcium carbonate formed on contact with air consolidates the
pigments Thus frescos contain mainly inorganic components While chemoautotrophic
nitrifiers and thiobacilli obtain their energy for growth by oxidizing ammonium and
reducing sulphur-compounds respectively heterotrophic bacteria and fungi depend on
organically bound carbon [Tate et al (1991) Lazar (1971) Petushkova et al (1986)
Jimenez et al (1981)] Thus primary colonization of photoautotrophic Cyanobacteria
chemolithoautotrophic nitrifying bacteria and sulphuric acid producing thiobacilli represent
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
30 Review of Literature
the first supply of organic matter The death and lysis of such bacteria promotes the
secondary settlement of heterotrophic bacteria and fungal populations (Calvo et al 1991)
Bacteria may derive from plants or pollen as many sequences obtained in this study
gave high score similarities with bacteria isolated from plants like Moraxella osloensis
Enterobacter cloace Enterobacter agglomerans and Pantoea endophytica Bacteria may
also derive from animal faeces like flies Bacillus Pseudomonas Aeromonas and Panteoa
(Ripka 2005) As Lazar and Dumitru (1973) reported studying mural paintings in a
Romanian monastery the genera Bacillus Arthrobacter and Pseudomonas have been
proved to produce salt efflorescences and were even considered to cause the blanching
phenomenon of frescoes (Jimenez et al 2000) Predominant bacterial genera are Bacillus
Streptomyces Arthrobacter Micrococcus and Pseudomonas [Weirich (1989)
Tate et al (1990) Arroyo et al (1997) Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
B) Fungi
It may be concluded that there is wide variety of fungal forms present on mural
paintings but Aspergillus and Alternaria were found dominating from all the experimental
sites next to them were Cladosporium Drechestera Fusarium Curvularia Chaetomium
Memnoniella Mycelia sterelai Pencillium Emericella Stachybotrytis Trichoderma
Phoma Monodictys Humicola and Epicoccum (Garg et al 1995)
The fungal genera most commonly found in lists of isolated taxa given in literature
are Alternaria Aspergillus Chaetomium Cladosporium Fusarium Penicillium and
Verticullum [Weirich (1989) Tate et al (1990) Guglielminetti et al (1994)
Garg et al (1995) Berner et al (1997) Ciferri (1999)] Some fungi having hard fruiting
bodies represented by sclerotia pycnidia perithecia cleistothecia and stroma could
organize themselves inside the painted layer Many fungal forms having such structures
were identified from our experimental sites viz Emericella nidulans A flavus
Chaetomium sp and Phoma sp etc These structures with little increase in humidity may
cause swelling in the paint film (Garg 1995)
Strains of species of Alternaria and Cladosporium both of them identified on the
mural paintings of the Palace of Schoumlnbrunn are the most common genera isolated from
stone and mural paintings in indoor environments with standard cultivation methods
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
31 Review of Literature
(Ventosa 2004) Saprophytic species of the genus Cladosporium are among the most
abundant fungi isolated in saltern samples Commonly isolated Cyanobacteria belong to
Nostoc and eukaryotic algae to Lyngbya and members of the Chlorophyceae such as
Chlorella Pseudococcomyxa and Pseudopleurococcus [Gorbushina et al (1987)
Calvo et al (1993) Arino et al (1996)]
They grow optimally on media with low water activity due to high salt or sugar
concentrations seem to propagate 70 vegetatively in the salterns and are thus
halotolerantosmotolerant species rather than simple flush-through occurrences
Cladiosporum herbarum was frequently isolated from hypersaline waters dead and dying
plant material air soil food fruit cereals paint and textiles (Ventosa 2004)
C) Algae
Most of the painted areas in temperature climate became covered with green algae
(Pleurococcus Protococcus and Trentopholia) while under tropical conditions blue green
algae of the genera Oscillatoria and Sytonema predominated (Garg 1995) The main
factors which contribute to the growth of algae on wall paintings are the presence of
moisture in the plaster as well as availability of visible light These conditions are quite
prevalent in the tropical climate but in temperature regions also algal growth on wall
paintings have been reported [Tonolo et al (1961) Pietrini et al (1991)]
D) Actinomycetes
Usually literature refers to specific aspects eg the occurrence of cyanobacteria
and algae in caves with natural openings to sunlight or those with artificial lighting fungi
and so forth Actinomycetes have been considered to be mainly confined to soils where
they find their natural habitat but despite intensive studies there are still many gaps in our
knowledge of the role played by actinomycetes in soil processes and biodegrations of
murals cave paintings (Groth et al 1999) In addition halophilic bacteria actinomycetes
and cyanobacteria are also capable of growing on salt-affected mural paintings
(Karbowska 2003)
Monte and Ferrari (1993) reviewed the mechanisms of biodeterioration in tombs
and underground churches The role of actinomycetes in the deterioration of frescoes in
hypogean environments was stressed by Agarossi et al (1985) Monte and Ferrari (1993)
Giacobini et al (1987) described the serious damage suffered by a whole series of famous
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
32 Review of Literature
frescoes in underground environments Actinomycetes were isolated from these mural
paintings located in crypts caves and tombs About 200 strains of actinomycetes were
isolated 60 of which were identified The most frequent species were Streptomyces albus
S cinereoruber S griseolus S vinaceus and some members of the Nocardia genus
Heterotrophic bacteria and actinomycetes were the most abundant microorganisms
on the frescoes of Etruscan tombs (Agarossi et al 1985) Bettini et al (1977) studied
some of the oldest Etruscan tombs (7th to 4th century BC) and found white-grey patinas
and spots from streptomycetes in the mural paintings They related the biodeterioration to
the microclimatic conditions (eg lower temperatures high RH) Monte and Ferrari (1993)
considered that colonization of the mural paintings was the result of selective competitive
and inhibitory dynamics among different microorganisms under different and changing
environmental conditions The pigments excreted by some actinomycetes were responsible
for the violet stains found on the walls of tombs in Tarquinia Similar stains were observed
in one of the Roman tombs the Circular Mausoleum the Necropolis of Carmona Spain
from which a Streptomyces sp producing violet pigments in culture media was isolated
214 Identification of biodeteriogens
The possibility of pigments and biodeteriogens identification in frescos and stone
monitoring is offered mostly by vibrational spectroscopy infrared thermography laser
induced fluorescence (LIF) laser induced breakdown spectroscopy (LIBS) XRF (X-Ray
Fluorescence) IR and UV emission Among them laser based methods allowing for in
situ or remote characterization of artwork surface were applied successfully for
prospecting diagnosis and maintenance (Colao et al 2005) The rep-PCR fingerprinting
of the isolates allowed determination of their genotypic diversity Studies that have
compared rep-PCR genomic fingerprint analysis with DNAndashDNA relatedness studies have
shown that the two techniques yield results that are in close agreement [Nick et al (1999)
Rademaker et al (2000)] These studies therefore suggest that rep-PCR fingerprinting can
be used as a genomic screening method to differentiate at the species level and to select
representatives for DNAndashDNA reassociation experiments (Heymann et al 2003)
The characterisation of bacteria was for example often limited to isolation from
group-specific media followed by microscopy [Sorlini et al (1987) Weirich (1989)
Tate et al (1990) and in more recent studies to morphological and physiological
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
33 Review of Literature
characteristics including miniaturised and automated systems such as API and BIOLOG
[Arroyo et al (1997) Jimmenez et al (2000) and Laiz et al (2000)] or to
chemotaxonomic characteristics [Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
Wagner et al (1994) demonstrated that conventional microbiological efforts can
fail to isolate all microorganisms present in natural samples DNA-based techniques used
to identify microorganisms have revealed only a smaller fraction of bacteria isolated from
artworks (Ward et al 1990 Rolleke et al 1996) Bacterial identification using molecular
techniques especially those including the sequencing of genes coding for ribosomal
16S rRNA is very important to study bacterial communities found on artefacts One such
method is Denaturing Gradient Gel Electrophoresis (DGGE) of PCR-amplified gene
fragments coding for rRNA (Muyzer et al 1993) that allows the separation of partial
16S rDNA amplified fragments of identical length but different sequence due to their
different melting behaviour in a gel system containing a gradient of denaturants
(Jimenez 2003)
Total genomic DNA was purified for 16S rRNA gene sequencing and rep-PCR
using a slight modification of the method of Pitcher et al (1989) as described by
Heyndrickx et al (1996) rep-PCR genomic fingerprinting was performed with the REP-
and (GTG)5 primers (Versalovic et al 1994) using the PCR conditions described
previously by Rademaker et al (1997) Electrophoresis and pattern analysis were further
performed as described by Heyrman et al (2003) 16S rRNA gene sequencing and
phylogenetic analysis were performed as described by Heyrman and Swings (2001)
Phylogenetic trees were constructed using the BioNumerics software (Applied Maths) by
applying the neighbour-joining and maximum-parsimony methods on a multiple alignment
similarity matrix The stability of relationships was assessed by a bootstrap analysis of
1000 datasets For determination of the G+C content and levels of DNAndashDNA
hybridization approximately 1 g biomass was harvested from agar plates DNA was
purified by using a combination of the protocols of Marmur (1961) and
Pitcher et al (1989) as described by Logan et al (2000) The G+C content of the DNA
was determined by HPLC (Mesbah et al 1989) using the further specifications given by
Logan et al (2000) DNAndashDNA hybridization experiments were performed using a
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
34 Review of Literature
modification of the microplate method of Ezaki et al (1989) as described by
Willems et al (2001)
215 Preservation and conservation
Nowadays the conservation and preservation of our cultural heritage is one of the
world main concerns particularly in Europe The increasing need for non-destructive
investigation tools has become a major issue as sampling is in most cases restricted in
view of the value or the uniqueness of the object Artworks as wall paintings in buildings
and monuments of historical interest are affected by environment physical (temperature
and humidity) and biological factors (biodeteriogens) and by human (pollutant releases)
impact and therefore modified over the time The term ldquoconservationrdquo may have many
different meanings in different fields Every intervention directed to the restoration and
safeguard of works of art is commonly considered as a conservation treatment For
example conservation can involve the cleaning procedures set up by chemists or the photo
documentation of the preservation of historical memory For the appropriate conservation
of works of art even the lighting systems in a museum or the control of the visitorrsquos
movements in a site should be monitored Chemical degradation which induces the flaking
of paintings and deterioration from rain wind dust and other environmental causes is
mainly responsible for the weakening of the porous structure and the surface layers of the
materials used in works of cultural heritage (Colao et al 2005)
216 Conservation history
Wall paintings are an integral part of monuments and sites and should be preserved
in situ Many of the problems affecting wall paintings are linked to the poor condition of
the building or structure its improper use lack of maintenance frequent repairs and
alterations Also frequent restorations unnecessary uncovering and use of inappropriate
methods and materials can result in irreparable damage Substandard and inadequate
practices and professional qualifications have led to unfortunate results It is for this reason
that an appropriate document covering the principles of proper conservation-restoration of
wall paintings is necessary
The Venice Charter (1964) has provided general principles for the conservation-
restoration of cultural heritage The Amsterdam Declaration (1975) introducing the
concept of integrated conservation and the Nara Document on Authenticity (1994) dealing
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
35 Review of Literature
with cultural diversity have expanded these principles Taking into account these and
additional relevant contributions such as the ICOM-CC Code of Ethics (1984) Document
of Pavia (1997) and ECCO Professional Guidelines (1997) the aim of this document is
to provide more specific principles for the protection preservation and the conservation
restoration of wall paintings This document therefore reflects basic and universally
applicable principles and practices and does not take into account particular problems of
regions or countries which can be supplemented at regional and national level by
providing further recommendations where necessary
217 Preservation techniques of the mural paintings
The removal of fat salts varnishes and pollutants from the surfaces of the works
of art are mostly done by chemical and mechanical methods At the end of the 19th
century the practices of restoration methods that do not inhibit further future interventions
was considered acceptable During the 1960s several chemicals such as polymeric resins
were synthesized and applied as a consolidation or protection agents The accepted idea
was that these substances could be removed at any time leaving a completely unaltered
substrate On the basis of origin archaeological objects can be classified as follows
(Carretti 2005)
1 Inorganic It includes siliceous and nonsiliceous materials Archaeological materials
produced from stones terracotta ceramics and glass can be included under siliceous
materials whereas objects made of metals can be included under nonsiliceous inorganic
materials Again metal objects can be classified as ferrous metals and non-ferrous metals
Objects made of iron are termed as ferrous metal objects whereas metal objects made from
other than iron is termed as non-ferrous metal objects
2 Organic It includes archival and anthropological materials Again archival materials
include paper bhojapatra tadapatra textiles wooden objects miniature paintings whereas
anthropological objects include bone and ivory leather feather and fur etc
In the past restoration of paintings and other old artwork often involved application
of acrylic resins to consolidate and protect them One of the most important tasks for
modern restorers is thus to remove these layers because it turns out that acrylic resins not
only by drastically changing the optics of the treated artwork but in many cases they
accelerate their degradation The scientists use an oil-in-water microemulsion with the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
36 Review of Literature
organic solvent para-xylene as the oil component The matrix makes the cleaning agent
viscous so that it cannot enter very far into the pores of a painting (Carretti 2005)
Nanoparticle treatment is the logical evolution of the Ferroni-Dini method
Dispersions of kinetically stable Ca (OH)2 nanoparticles in non-aqueous solvents solved
most of the drawbacks of the microsized powders Stable dispersions of calcium hydroxide
have been successfully applied (replacing polymers) as fixatives to re-adhere lifted paint
layers during many restoration workshops in Italy and in Europe as a consolidant The
FerronindashDini method (two steps the application of a saturated solution of ammonium
carbonate (NH4)2CO3 and the treatment with a barium hydroxide solution Ba(OH)2 also
called the barium method has long been the acknowledged method for the removal of
salts that threaten paintings reinforcing at the same time the porous structure However
commercially available carbonates and hydroxide powders have dimensions of several
micrometres much larger than the pores on the paint surface This means they donrsquot
penetrate the painting well and there is also a risk of damaging the artwork by a white
glaze forming on the surface (Berger 2006) Restoration should provide the reinforcement
of the porous structure and the consolidation of the surface layer of arte facts A few
simple principles can be considered to define the most appropriate restoration method
1) The treatment should be reversible so that one can revert to the original status of the
work of art at any desired time
2) All the applied chemicals must ensure the maximum durability and the chemical
inertness
3) The applied chemicals must invert the degradation processes without altering the
chemical composition of the artefacts and their physico-chemical and mechanical
properties (Baglioni 2006)
218 Commercial preservative used for preservation of mural paintings
Cleaning was done using soft brushes vacuum cleaner and Gumma paine (dough)
a natural latex sponge Areas near the window were very dirty with black soot and were
cleaned with micro fibrous cloths moistened with synperonic N (surfactant alkyl phenol
ethoxylate based on nonyl phenol) and neutralized with clean water In several places the
paint layers had separated from the substrate (exfoli-ation) In that cases loose paint flakes
were stuck back using Paraloid B72 (10 solution in ethanol) as sparingly as possible
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
37 Review of Literature
Paraloid was injected with syringe behind the exfoliated area twice pushed and held back
with Melinex (polyester film) until fixed on the third application (Bionda et al 2002)
In a period of significant growth of molds and intensive efforts to stop the mold
contamination some of the lines of certain paintings were obscured or faded Solutions of
ethanol formalin 91 and Thiabendazole (TBZ) were used but they were not very
effective Para-formaldehyde fumigation was adopted beginning in 1981 to establish an
emergency treatment sensitivity of microorganisms from studied samples was tested
against Desogen by adding 1-3 (v v) in serial dilutions The best concentration
3 (vv) was applied with a brush to prevent spreading of the spores In order to overcome
the problem of fungal attack suitable fungicides carbendizeme or kiroxy-I or 5 solute of
N formaldehyde can be used Shellac solution in spirit or 2 solution of polyvinaycletate
in toluene can be used as preservative and consolidantsTo control insect and fungal attack
fumigants like pyrethrum DDT or 5 solution of sodium penta chlorophenate in kerosene
oil 2 to 5 solution of PVA in toluene or 2 to 5 solution of paraloid B-72 in toluene or
acetone be used (Miura 2009) Microclimatic conditions constitute a critical factor in the
conservation of cave paintings The unstable microclimatic condition is one of the factors
that always affect the state of conservation of mural paintings In the environmental-
monument system knowledge of the functional environment and climatic conditions of the
surroundings are necessary for the identification of causes of decay (Singh 2011)
Furthermore the risk of formation of indoor bioaerosols in residential and public
buildings (offices schools museums etc) has attracted interest in the last years due to
socio-economic as well as sanitary reasons (Ripka 2005) Thus it is important in aspects of
health and maintenance of Cultural Heritage to analyse the complete microflora to further
develop biocides for harmful microorganisms and methods for restoration of damaged
objects of art The biocidal testing was carried out on one representative algal species of
the two classes of algae viz Chlorococcum sp (green) and Chroococcus sp (blue-green)
found to be common in all the samples Efficiency tests were carried out both in liquid as
well as solid media containing algal suspensions by adding a biocide solution of known
concentration and determining the growth of the microorganism after the incubation
period The biocides used for the past studies were
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
28 Review of Literature
Tate and Rebrikova (1990) thought autotrophic nitrifying bacteria to be the first colonisers
of damaged frescoes and building materials in the cathedral of the nativity of the Virgin in
the Pafnutii-Borovskii monastery (Russia) The bulk of research on biodeterioration of
mural paintings has focused on explaining the observed phenomena by analysing the
microflora present Following this approach a precise characterisation of the
microorganisms using a polyphasic approach was never the first goal
Only a few studies included genomic fingerprinting (16S rDNA sequence analysis)
for the characterisation of bacteria associated with damage on mural paintings
[Rolleke (1996) Pinar et al (2001)] Previous studies based on culture-dependent
techniques showed that the flora present on frescos are fungi (predominant species of
Penicillium Aspergillus Cladosporium and Engyodontium) (Guglielminetti et al 1994)
bacteria (predominant species of Bacillus Arthrobacter Micrococcus Streptomyces and
Pseudomonas) (Heyrman et al 1999) cyanobacteria and eukaryotic algae (species of
Nostoc Lyngbya and Chlorophyceae) (Arino et al 1996 Calvo et al 1993) The killing
effect of an antimicrobial agent on a microorganism can be assessed in several ways
(1) Lethal activity may be expressed as the rate of killing by a fixed concentration
of drug under controlled conditions This rate is determined by measuring the number of
viable bacteria at various time intervals The resulting graphic depiction is known as the
time-kill curve Bacterial killing rates are in part dependent on the class of antibiotic and
the concentration of this agent With certain classes of antibiotics (eg aminoglycosides
and fluoroquino-lones) the rate of killing increases with increased drug concentrations up
to a point of maximum effect This is termed concentration-dependent bactericidal activity
In contrast the killing rates of szlig-lactam agents and vancomycin are relatively slow and
continue only as long as the concentrations are in excess of the MIC This rate of killing is
termed time-dependent bactericidal activity
(2) The minimal concentration of drug needed to kill most of the viable organisms
after incubation for a fixed length of time (generally 24 hours) under a given set of
conditions is the most common estimation of bactericidal activity and is known as either
the minimal bactericidal concentration (MBC) or the minimal lethal concentration (MLC)
It will be referred to in this document as the MBC Unfortunately the definition of the
MBC (999 killing of the final inoculum) is somewhat arbitrary and separates the
bacteria into two populations ndash a segrega-tion which might not have biological relevance
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
29 Review of Literature
The determination of the MBC moreover is so subject to methodologic variables that the
clinical relevance of MBCs is nearly impossible to assess particularly for certain pathogen
and drug combinations (eg Staphylococci and beta-lactam agents)
(3) The serum of a patient receiving an antibiotic may be tested against the
infecting microorganism This can be done using time-kill curve methodology (ie serum
bactericidal rate) or using dilution methodology (ie serum bactericidal titer) The
principles of these methods as well as the influence of biological and technical factors are
similar (Barry et al 1999)
213 Microbial flora associated with deteriorated mural paintings
A great deal of research has been done in this field mainly by using cultivation dependent
methods However by using culture-dependent methods only a very small proportion of
microorganisms can be obtained Far less than 1 of organisms in the environment can be
cultivated by standard cultivation techniques (Pace 1996) Recent studies have shown that
culture-dependent techniques yielded mainly sporeforming bacteria suggesting that plating
leads to an over estimation of the number of spore-forming bacteria A wide number of
investigations have shown that in addition to chemical and physical processes
microorganisms play a major role in degradation of objects of art such as paintings stone-
works wood paper masonry leather parchment glass and metal (Ripka 2005)
A) Bacteria
In general growth of diverse organisms on mural paintings is supported by
humidity slight alkaline pH values and the presence of organic and inorganic nutrient
sources (Weirich 1989) In mural paintings pigments are suspended in water or oil often
binders such as casein and milk are used and they are supplied on the damp lime plaster
(Ciferri 1999) The calcium carbonate formed on contact with air consolidates the
pigments Thus frescos contain mainly inorganic components While chemoautotrophic
nitrifiers and thiobacilli obtain their energy for growth by oxidizing ammonium and
reducing sulphur-compounds respectively heterotrophic bacteria and fungi depend on
organically bound carbon [Tate et al (1991) Lazar (1971) Petushkova et al (1986)
Jimenez et al (1981)] Thus primary colonization of photoautotrophic Cyanobacteria
chemolithoautotrophic nitrifying bacteria and sulphuric acid producing thiobacilli represent
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
30 Review of Literature
the first supply of organic matter The death and lysis of such bacteria promotes the
secondary settlement of heterotrophic bacteria and fungal populations (Calvo et al 1991)
Bacteria may derive from plants or pollen as many sequences obtained in this study
gave high score similarities with bacteria isolated from plants like Moraxella osloensis
Enterobacter cloace Enterobacter agglomerans and Pantoea endophytica Bacteria may
also derive from animal faeces like flies Bacillus Pseudomonas Aeromonas and Panteoa
(Ripka 2005) As Lazar and Dumitru (1973) reported studying mural paintings in a
Romanian monastery the genera Bacillus Arthrobacter and Pseudomonas have been
proved to produce salt efflorescences and were even considered to cause the blanching
phenomenon of frescoes (Jimenez et al 2000) Predominant bacterial genera are Bacillus
Streptomyces Arthrobacter Micrococcus and Pseudomonas [Weirich (1989)
Tate et al (1990) Arroyo et al (1997) Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
B) Fungi
It may be concluded that there is wide variety of fungal forms present on mural
paintings but Aspergillus and Alternaria were found dominating from all the experimental
sites next to them were Cladosporium Drechestera Fusarium Curvularia Chaetomium
Memnoniella Mycelia sterelai Pencillium Emericella Stachybotrytis Trichoderma
Phoma Monodictys Humicola and Epicoccum (Garg et al 1995)
The fungal genera most commonly found in lists of isolated taxa given in literature
are Alternaria Aspergillus Chaetomium Cladosporium Fusarium Penicillium and
Verticullum [Weirich (1989) Tate et al (1990) Guglielminetti et al (1994)
Garg et al (1995) Berner et al (1997) Ciferri (1999)] Some fungi having hard fruiting
bodies represented by sclerotia pycnidia perithecia cleistothecia and stroma could
organize themselves inside the painted layer Many fungal forms having such structures
were identified from our experimental sites viz Emericella nidulans A flavus
Chaetomium sp and Phoma sp etc These structures with little increase in humidity may
cause swelling in the paint film (Garg 1995)
Strains of species of Alternaria and Cladosporium both of them identified on the
mural paintings of the Palace of Schoumlnbrunn are the most common genera isolated from
stone and mural paintings in indoor environments with standard cultivation methods
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
31 Review of Literature
(Ventosa 2004) Saprophytic species of the genus Cladosporium are among the most
abundant fungi isolated in saltern samples Commonly isolated Cyanobacteria belong to
Nostoc and eukaryotic algae to Lyngbya and members of the Chlorophyceae such as
Chlorella Pseudococcomyxa and Pseudopleurococcus [Gorbushina et al (1987)
Calvo et al (1993) Arino et al (1996)]
They grow optimally on media with low water activity due to high salt or sugar
concentrations seem to propagate 70 vegetatively in the salterns and are thus
halotolerantosmotolerant species rather than simple flush-through occurrences
Cladiosporum herbarum was frequently isolated from hypersaline waters dead and dying
plant material air soil food fruit cereals paint and textiles (Ventosa 2004)
C) Algae
Most of the painted areas in temperature climate became covered with green algae
(Pleurococcus Protococcus and Trentopholia) while under tropical conditions blue green
algae of the genera Oscillatoria and Sytonema predominated (Garg 1995) The main
factors which contribute to the growth of algae on wall paintings are the presence of
moisture in the plaster as well as availability of visible light These conditions are quite
prevalent in the tropical climate but in temperature regions also algal growth on wall
paintings have been reported [Tonolo et al (1961) Pietrini et al (1991)]
D) Actinomycetes
Usually literature refers to specific aspects eg the occurrence of cyanobacteria
and algae in caves with natural openings to sunlight or those with artificial lighting fungi
and so forth Actinomycetes have been considered to be mainly confined to soils where
they find their natural habitat but despite intensive studies there are still many gaps in our
knowledge of the role played by actinomycetes in soil processes and biodegrations of
murals cave paintings (Groth et al 1999) In addition halophilic bacteria actinomycetes
and cyanobacteria are also capable of growing on salt-affected mural paintings
(Karbowska 2003)
Monte and Ferrari (1993) reviewed the mechanisms of biodeterioration in tombs
and underground churches The role of actinomycetes in the deterioration of frescoes in
hypogean environments was stressed by Agarossi et al (1985) Monte and Ferrari (1993)
Giacobini et al (1987) described the serious damage suffered by a whole series of famous
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
32 Review of Literature
frescoes in underground environments Actinomycetes were isolated from these mural
paintings located in crypts caves and tombs About 200 strains of actinomycetes were
isolated 60 of which were identified The most frequent species were Streptomyces albus
S cinereoruber S griseolus S vinaceus and some members of the Nocardia genus
Heterotrophic bacteria and actinomycetes were the most abundant microorganisms
on the frescoes of Etruscan tombs (Agarossi et al 1985) Bettini et al (1977) studied
some of the oldest Etruscan tombs (7th to 4th century BC) and found white-grey patinas
and spots from streptomycetes in the mural paintings They related the biodeterioration to
the microclimatic conditions (eg lower temperatures high RH) Monte and Ferrari (1993)
considered that colonization of the mural paintings was the result of selective competitive
and inhibitory dynamics among different microorganisms under different and changing
environmental conditions The pigments excreted by some actinomycetes were responsible
for the violet stains found on the walls of tombs in Tarquinia Similar stains were observed
in one of the Roman tombs the Circular Mausoleum the Necropolis of Carmona Spain
from which a Streptomyces sp producing violet pigments in culture media was isolated
214 Identification of biodeteriogens
The possibility of pigments and biodeteriogens identification in frescos and stone
monitoring is offered mostly by vibrational spectroscopy infrared thermography laser
induced fluorescence (LIF) laser induced breakdown spectroscopy (LIBS) XRF (X-Ray
Fluorescence) IR and UV emission Among them laser based methods allowing for in
situ or remote characterization of artwork surface were applied successfully for
prospecting diagnosis and maintenance (Colao et al 2005) The rep-PCR fingerprinting
of the isolates allowed determination of their genotypic diversity Studies that have
compared rep-PCR genomic fingerprint analysis with DNAndashDNA relatedness studies have
shown that the two techniques yield results that are in close agreement [Nick et al (1999)
Rademaker et al (2000)] These studies therefore suggest that rep-PCR fingerprinting can
be used as a genomic screening method to differentiate at the species level and to select
representatives for DNAndashDNA reassociation experiments (Heymann et al 2003)
The characterisation of bacteria was for example often limited to isolation from
group-specific media followed by microscopy [Sorlini et al (1987) Weirich (1989)
Tate et al (1990) and in more recent studies to morphological and physiological
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
33 Review of Literature
characteristics including miniaturised and automated systems such as API and BIOLOG
[Arroyo et al (1997) Jimmenez et al (2000) and Laiz et al (2000)] or to
chemotaxonomic characteristics [Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
Wagner et al (1994) demonstrated that conventional microbiological efforts can
fail to isolate all microorganisms present in natural samples DNA-based techniques used
to identify microorganisms have revealed only a smaller fraction of bacteria isolated from
artworks (Ward et al 1990 Rolleke et al 1996) Bacterial identification using molecular
techniques especially those including the sequencing of genes coding for ribosomal
16S rRNA is very important to study bacterial communities found on artefacts One such
method is Denaturing Gradient Gel Electrophoresis (DGGE) of PCR-amplified gene
fragments coding for rRNA (Muyzer et al 1993) that allows the separation of partial
16S rDNA amplified fragments of identical length but different sequence due to their
different melting behaviour in a gel system containing a gradient of denaturants
(Jimenez 2003)
Total genomic DNA was purified for 16S rRNA gene sequencing and rep-PCR
using a slight modification of the method of Pitcher et al (1989) as described by
Heyndrickx et al (1996) rep-PCR genomic fingerprinting was performed with the REP-
and (GTG)5 primers (Versalovic et al 1994) using the PCR conditions described
previously by Rademaker et al (1997) Electrophoresis and pattern analysis were further
performed as described by Heyrman et al (2003) 16S rRNA gene sequencing and
phylogenetic analysis were performed as described by Heyrman and Swings (2001)
Phylogenetic trees were constructed using the BioNumerics software (Applied Maths) by
applying the neighbour-joining and maximum-parsimony methods on a multiple alignment
similarity matrix The stability of relationships was assessed by a bootstrap analysis of
1000 datasets For determination of the G+C content and levels of DNAndashDNA
hybridization approximately 1 g biomass was harvested from agar plates DNA was
purified by using a combination of the protocols of Marmur (1961) and
Pitcher et al (1989) as described by Logan et al (2000) The G+C content of the DNA
was determined by HPLC (Mesbah et al 1989) using the further specifications given by
Logan et al (2000) DNAndashDNA hybridization experiments were performed using a
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
34 Review of Literature
modification of the microplate method of Ezaki et al (1989) as described by
Willems et al (2001)
215 Preservation and conservation
Nowadays the conservation and preservation of our cultural heritage is one of the
world main concerns particularly in Europe The increasing need for non-destructive
investigation tools has become a major issue as sampling is in most cases restricted in
view of the value or the uniqueness of the object Artworks as wall paintings in buildings
and monuments of historical interest are affected by environment physical (temperature
and humidity) and biological factors (biodeteriogens) and by human (pollutant releases)
impact and therefore modified over the time The term ldquoconservationrdquo may have many
different meanings in different fields Every intervention directed to the restoration and
safeguard of works of art is commonly considered as a conservation treatment For
example conservation can involve the cleaning procedures set up by chemists or the photo
documentation of the preservation of historical memory For the appropriate conservation
of works of art even the lighting systems in a museum or the control of the visitorrsquos
movements in a site should be monitored Chemical degradation which induces the flaking
of paintings and deterioration from rain wind dust and other environmental causes is
mainly responsible for the weakening of the porous structure and the surface layers of the
materials used in works of cultural heritage (Colao et al 2005)
216 Conservation history
Wall paintings are an integral part of monuments and sites and should be preserved
in situ Many of the problems affecting wall paintings are linked to the poor condition of
the building or structure its improper use lack of maintenance frequent repairs and
alterations Also frequent restorations unnecessary uncovering and use of inappropriate
methods and materials can result in irreparable damage Substandard and inadequate
practices and professional qualifications have led to unfortunate results It is for this reason
that an appropriate document covering the principles of proper conservation-restoration of
wall paintings is necessary
The Venice Charter (1964) has provided general principles for the conservation-
restoration of cultural heritage The Amsterdam Declaration (1975) introducing the
concept of integrated conservation and the Nara Document on Authenticity (1994) dealing
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
35 Review of Literature
with cultural diversity have expanded these principles Taking into account these and
additional relevant contributions such as the ICOM-CC Code of Ethics (1984) Document
of Pavia (1997) and ECCO Professional Guidelines (1997) the aim of this document is
to provide more specific principles for the protection preservation and the conservation
restoration of wall paintings This document therefore reflects basic and universally
applicable principles and practices and does not take into account particular problems of
regions or countries which can be supplemented at regional and national level by
providing further recommendations where necessary
217 Preservation techniques of the mural paintings
The removal of fat salts varnishes and pollutants from the surfaces of the works
of art are mostly done by chemical and mechanical methods At the end of the 19th
century the practices of restoration methods that do not inhibit further future interventions
was considered acceptable During the 1960s several chemicals such as polymeric resins
were synthesized and applied as a consolidation or protection agents The accepted idea
was that these substances could be removed at any time leaving a completely unaltered
substrate On the basis of origin archaeological objects can be classified as follows
(Carretti 2005)
1 Inorganic It includes siliceous and nonsiliceous materials Archaeological materials
produced from stones terracotta ceramics and glass can be included under siliceous
materials whereas objects made of metals can be included under nonsiliceous inorganic
materials Again metal objects can be classified as ferrous metals and non-ferrous metals
Objects made of iron are termed as ferrous metal objects whereas metal objects made from
other than iron is termed as non-ferrous metal objects
2 Organic It includes archival and anthropological materials Again archival materials
include paper bhojapatra tadapatra textiles wooden objects miniature paintings whereas
anthropological objects include bone and ivory leather feather and fur etc
In the past restoration of paintings and other old artwork often involved application
of acrylic resins to consolidate and protect them One of the most important tasks for
modern restorers is thus to remove these layers because it turns out that acrylic resins not
only by drastically changing the optics of the treated artwork but in many cases they
accelerate their degradation The scientists use an oil-in-water microemulsion with the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
36 Review of Literature
organic solvent para-xylene as the oil component The matrix makes the cleaning agent
viscous so that it cannot enter very far into the pores of a painting (Carretti 2005)
Nanoparticle treatment is the logical evolution of the Ferroni-Dini method
Dispersions of kinetically stable Ca (OH)2 nanoparticles in non-aqueous solvents solved
most of the drawbacks of the microsized powders Stable dispersions of calcium hydroxide
have been successfully applied (replacing polymers) as fixatives to re-adhere lifted paint
layers during many restoration workshops in Italy and in Europe as a consolidant The
FerronindashDini method (two steps the application of a saturated solution of ammonium
carbonate (NH4)2CO3 and the treatment with a barium hydroxide solution Ba(OH)2 also
called the barium method has long been the acknowledged method for the removal of
salts that threaten paintings reinforcing at the same time the porous structure However
commercially available carbonates and hydroxide powders have dimensions of several
micrometres much larger than the pores on the paint surface This means they donrsquot
penetrate the painting well and there is also a risk of damaging the artwork by a white
glaze forming on the surface (Berger 2006) Restoration should provide the reinforcement
of the porous structure and the consolidation of the surface layer of arte facts A few
simple principles can be considered to define the most appropriate restoration method
1) The treatment should be reversible so that one can revert to the original status of the
work of art at any desired time
2) All the applied chemicals must ensure the maximum durability and the chemical
inertness
3) The applied chemicals must invert the degradation processes without altering the
chemical composition of the artefacts and their physico-chemical and mechanical
properties (Baglioni 2006)
218 Commercial preservative used for preservation of mural paintings
Cleaning was done using soft brushes vacuum cleaner and Gumma paine (dough)
a natural latex sponge Areas near the window were very dirty with black soot and were
cleaned with micro fibrous cloths moistened with synperonic N (surfactant alkyl phenol
ethoxylate based on nonyl phenol) and neutralized with clean water In several places the
paint layers had separated from the substrate (exfoli-ation) In that cases loose paint flakes
were stuck back using Paraloid B72 (10 solution in ethanol) as sparingly as possible
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
37 Review of Literature
Paraloid was injected with syringe behind the exfoliated area twice pushed and held back
with Melinex (polyester film) until fixed on the third application (Bionda et al 2002)
In a period of significant growth of molds and intensive efforts to stop the mold
contamination some of the lines of certain paintings were obscured or faded Solutions of
ethanol formalin 91 and Thiabendazole (TBZ) were used but they were not very
effective Para-formaldehyde fumigation was adopted beginning in 1981 to establish an
emergency treatment sensitivity of microorganisms from studied samples was tested
against Desogen by adding 1-3 (v v) in serial dilutions The best concentration
3 (vv) was applied with a brush to prevent spreading of the spores In order to overcome
the problem of fungal attack suitable fungicides carbendizeme or kiroxy-I or 5 solute of
N formaldehyde can be used Shellac solution in spirit or 2 solution of polyvinaycletate
in toluene can be used as preservative and consolidantsTo control insect and fungal attack
fumigants like pyrethrum DDT or 5 solution of sodium penta chlorophenate in kerosene
oil 2 to 5 solution of PVA in toluene or 2 to 5 solution of paraloid B-72 in toluene or
acetone be used (Miura 2009) Microclimatic conditions constitute a critical factor in the
conservation of cave paintings The unstable microclimatic condition is one of the factors
that always affect the state of conservation of mural paintings In the environmental-
monument system knowledge of the functional environment and climatic conditions of the
surroundings are necessary for the identification of causes of decay (Singh 2011)
Furthermore the risk of formation of indoor bioaerosols in residential and public
buildings (offices schools museums etc) has attracted interest in the last years due to
socio-economic as well as sanitary reasons (Ripka 2005) Thus it is important in aspects of
health and maintenance of Cultural Heritage to analyse the complete microflora to further
develop biocides for harmful microorganisms and methods for restoration of damaged
objects of art The biocidal testing was carried out on one representative algal species of
the two classes of algae viz Chlorococcum sp (green) and Chroococcus sp (blue-green)
found to be common in all the samples Efficiency tests were carried out both in liquid as
well as solid media containing algal suspensions by adding a biocide solution of known
concentration and determining the growth of the microorganism after the incubation
period The biocides used for the past studies were
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
29 Review of Literature
The determination of the MBC moreover is so subject to methodologic variables that the
clinical relevance of MBCs is nearly impossible to assess particularly for certain pathogen
and drug combinations (eg Staphylococci and beta-lactam agents)
(3) The serum of a patient receiving an antibiotic may be tested against the
infecting microorganism This can be done using time-kill curve methodology (ie serum
bactericidal rate) or using dilution methodology (ie serum bactericidal titer) The
principles of these methods as well as the influence of biological and technical factors are
similar (Barry et al 1999)
213 Microbial flora associated with deteriorated mural paintings
A great deal of research has been done in this field mainly by using cultivation dependent
methods However by using culture-dependent methods only a very small proportion of
microorganisms can be obtained Far less than 1 of organisms in the environment can be
cultivated by standard cultivation techniques (Pace 1996) Recent studies have shown that
culture-dependent techniques yielded mainly sporeforming bacteria suggesting that plating
leads to an over estimation of the number of spore-forming bacteria A wide number of
investigations have shown that in addition to chemical and physical processes
microorganisms play a major role in degradation of objects of art such as paintings stone-
works wood paper masonry leather parchment glass and metal (Ripka 2005)
A) Bacteria
In general growth of diverse organisms on mural paintings is supported by
humidity slight alkaline pH values and the presence of organic and inorganic nutrient
sources (Weirich 1989) In mural paintings pigments are suspended in water or oil often
binders such as casein and milk are used and they are supplied on the damp lime plaster
(Ciferri 1999) The calcium carbonate formed on contact with air consolidates the
pigments Thus frescos contain mainly inorganic components While chemoautotrophic
nitrifiers and thiobacilli obtain their energy for growth by oxidizing ammonium and
reducing sulphur-compounds respectively heterotrophic bacteria and fungi depend on
organically bound carbon [Tate et al (1991) Lazar (1971) Petushkova et al (1986)
Jimenez et al (1981)] Thus primary colonization of photoautotrophic Cyanobacteria
chemolithoautotrophic nitrifying bacteria and sulphuric acid producing thiobacilli represent
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
30 Review of Literature
the first supply of organic matter The death and lysis of such bacteria promotes the
secondary settlement of heterotrophic bacteria and fungal populations (Calvo et al 1991)
Bacteria may derive from plants or pollen as many sequences obtained in this study
gave high score similarities with bacteria isolated from plants like Moraxella osloensis
Enterobacter cloace Enterobacter agglomerans and Pantoea endophytica Bacteria may
also derive from animal faeces like flies Bacillus Pseudomonas Aeromonas and Panteoa
(Ripka 2005) As Lazar and Dumitru (1973) reported studying mural paintings in a
Romanian monastery the genera Bacillus Arthrobacter and Pseudomonas have been
proved to produce salt efflorescences and were even considered to cause the blanching
phenomenon of frescoes (Jimenez et al 2000) Predominant bacterial genera are Bacillus
Streptomyces Arthrobacter Micrococcus and Pseudomonas [Weirich (1989)
Tate et al (1990) Arroyo et al (1997) Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
B) Fungi
It may be concluded that there is wide variety of fungal forms present on mural
paintings but Aspergillus and Alternaria were found dominating from all the experimental
sites next to them were Cladosporium Drechestera Fusarium Curvularia Chaetomium
Memnoniella Mycelia sterelai Pencillium Emericella Stachybotrytis Trichoderma
Phoma Monodictys Humicola and Epicoccum (Garg et al 1995)
The fungal genera most commonly found in lists of isolated taxa given in literature
are Alternaria Aspergillus Chaetomium Cladosporium Fusarium Penicillium and
Verticullum [Weirich (1989) Tate et al (1990) Guglielminetti et al (1994)
Garg et al (1995) Berner et al (1997) Ciferri (1999)] Some fungi having hard fruiting
bodies represented by sclerotia pycnidia perithecia cleistothecia and stroma could
organize themselves inside the painted layer Many fungal forms having such structures
were identified from our experimental sites viz Emericella nidulans A flavus
Chaetomium sp and Phoma sp etc These structures with little increase in humidity may
cause swelling in the paint film (Garg 1995)
Strains of species of Alternaria and Cladosporium both of them identified on the
mural paintings of the Palace of Schoumlnbrunn are the most common genera isolated from
stone and mural paintings in indoor environments with standard cultivation methods
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
31 Review of Literature
(Ventosa 2004) Saprophytic species of the genus Cladosporium are among the most
abundant fungi isolated in saltern samples Commonly isolated Cyanobacteria belong to
Nostoc and eukaryotic algae to Lyngbya and members of the Chlorophyceae such as
Chlorella Pseudococcomyxa and Pseudopleurococcus [Gorbushina et al (1987)
Calvo et al (1993) Arino et al (1996)]
They grow optimally on media with low water activity due to high salt or sugar
concentrations seem to propagate 70 vegetatively in the salterns and are thus
halotolerantosmotolerant species rather than simple flush-through occurrences
Cladiosporum herbarum was frequently isolated from hypersaline waters dead and dying
plant material air soil food fruit cereals paint and textiles (Ventosa 2004)
C) Algae
Most of the painted areas in temperature climate became covered with green algae
(Pleurococcus Protococcus and Trentopholia) while under tropical conditions blue green
algae of the genera Oscillatoria and Sytonema predominated (Garg 1995) The main
factors which contribute to the growth of algae on wall paintings are the presence of
moisture in the plaster as well as availability of visible light These conditions are quite
prevalent in the tropical climate but in temperature regions also algal growth on wall
paintings have been reported [Tonolo et al (1961) Pietrini et al (1991)]
D) Actinomycetes
Usually literature refers to specific aspects eg the occurrence of cyanobacteria
and algae in caves with natural openings to sunlight or those with artificial lighting fungi
and so forth Actinomycetes have been considered to be mainly confined to soils where
they find their natural habitat but despite intensive studies there are still many gaps in our
knowledge of the role played by actinomycetes in soil processes and biodegrations of
murals cave paintings (Groth et al 1999) In addition halophilic bacteria actinomycetes
and cyanobacteria are also capable of growing on salt-affected mural paintings
(Karbowska 2003)
Monte and Ferrari (1993) reviewed the mechanisms of biodeterioration in tombs
and underground churches The role of actinomycetes in the deterioration of frescoes in
hypogean environments was stressed by Agarossi et al (1985) Monte and Ferrari (1993)
Giacobini et al (1987) described the serious damage suffered by a whole series of famous
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
32 Review of Literature
frescoes in underground environments Actinomycetes were isolated from these mural
paintings located in crypts caves and tombs About 200 strains of actinomycetes were
isolated 60 of which were identified The most frequent species were Streptomyces albus
S cinereoruber S griseolus S vinaceus and some members of the Nocardia genus
Heterotrophic bacteria and actinomycetes were the most abundant microorganisms
on the frescoes of Etruscan tombs (Agarossi et al 1985) Bettini et al (1977) studied
some of the oldest Etruscan tombs (7th to 4th century BC) and found white-grey patinas
and spots from streptomycetes in the mural paintings They related the biodeterioration to
the microclimatic conditions (eg lower temperatures high RH) Monte and Ferrari (1993)
considered that colonization of the mural paintings was the result of selective competitive
and inhibitory dynamics among different microorganisms under different and changing
environmental conditions The pigments excreted by some actinomycetes were responsible
for the violet stains found on the walls of tombs in Tarquinia Similar stains were observed
in one of the Roman tombs the Circular Mausoleum the Necropolis of Carmona Spain
from which a Streptomyces sp producing violet pigments in culture media was isolated
214 Identification of biodeteriogens
The possibility of pigments and biodeteriogens identification in frescos and stone
monitoring is offered mostly by vibrational spectroscopy infrared thermography laser
induced fluorescence (LIF) laser induced breakdown spectroscopy (LIBS) XRF (X-Ray
Fluorescence) IR and UV emission Among them laser based methods allowing for in
situ or remote characterization of artwork surface were applied successfully for
prospecting diagnosis and maintenance (Colao et al 2005) The rep-PCR fingerprinting
of the isolates allowed determination of their genotypic diversity Studies that have
compared rep-PCR genomic fingerprint analysis with DNAndashDNA relatedness studies have
shown that the two techniques yield results that are in close agreement [Nick et al (1999)
Rademaker et al (2000)] These studies therefore suggest that rep-PCR fingerprinting can
be used as a genomic screening method to differentiate at the species level and to select
representatives for DNAndashDNA reassociation experiments (Heymann et al 2003)
The characterisation of bacteria was for example often limited to isolation from
group-specific media followed by microscopy [Sorlini et al (1987) Weirich (1989)
Tate et al (1990) and in more recent studies to morphological and physiological
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
33 Review of Literature
characteristics including miniaturised and automated systems such as API and BIOLOG
[Arroyo et al (1997) Jimmenez et al (2000) and Laiz et al (2000)] or to
chemotaxonomic characteristics [Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
Wagner et al (1994) demonstrated that conventional microbiological efforts can
fail to isolate all microorganisms present in natural samples DNA-based techniques used
to identify microorganisms have revealed only a smaller fraction of bacteria isolated from
artworks (Ward et al 1990 Rolleke et al 1996) Bacterial identification using molecular
techniques especially those including the sequencing of genes coding for ribosomal
16S rRNA is very important to study bacterial communities found on artefacts One such
method is Denaturing Gradient Gel Electrophoresis (DGGE) of PCR-amplified gene
fragments coding for rRNA (Muyzer et al 1993) that allows the separation of partial
16S rDNA amplified fragments of identical length but different sequence due to their
different melting behaviour in a gel system containing a gradient of denaturants
(Jimenez 2003)
Total genomic DNA was purified for 16S rRNA gene sequencing and rep-PCR
using a slight modification of the method of Pitcher et al (1989) as described by
Heyndrickx et al (1996) rep-PCR genomic fingerprinting was performed with the REP-
and (GTG)5 primers (Versalovic et al 1994) using the PCR conditions described
previously by Rademaker et al (1997) Electrophoresis and pattern analysis were further
performed as described by Heyrman et al (2003) 16S rRNA gene sequencing and
phylogenetic analysis were performed as described by Heyrman and Swings (2001)
Phylogenetic trees were constructed using the BioNumerics software (Applied Maths) by
applying the neighbour-joining and maximum-parsimony methods on a multiple alignment
similarity matrix The stability of relationships was assessed by a bootstrap analysis of
1000 datasets For determination of the G+C content and levels of DNAndashDNA
hybridization approximately 1 g biomass was harvested from agar plates DNA was
purified by using a combination of the protocols of Marmur (1961) and
Pitcher et al (1989) as described by Logan et al (2000) The G+C content of the DNA
was determined by HPLC (Mesbah et al 1989) using the further specifications given by
Logan et al (2000) DNAndashDNA hybridization experiments were performed using a
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
34 Review of Literature
modification of the microplate method of Ezaki et al (1989) as described by
Willems et al (2001)
215 Preservation and conservation
Nowadays the conservation and preservation of our cultural heritage is one of the
world main concerns particularly in Europe The increasing need for non-destructive
investigation tools has become a major issue as sampling is in most cases restricted in
view of the value or the uniqueness of the object Artworks as wall paintings in buildings
and monuments of historical interest are affected by environment physical (temperature
and humidity) and biological factors (biodeteriogens) and by human (pollutant releases)
impact and therefore modified over the time The term ldquoconservationrdquo may have many
different meanings in different fields Every intervention directed to the restoration and
safeguard of works of art is commonly considered as a conservation treatment For
example conservation can involve the cleaning procedures set up by chemists or the photo
documentation of the preservation of historical memory For the appropriate conservation
of works of art even the lighting systems in a museum or the control of the visitorrsquos
movements in a site should be monitored Chemical degradation which induces the flaking
of paintings and deterioration from rain wind dust and other environmental causes is
mainly responsible for the weakening of the porous structure and the surface layers of the
materials used in works of cultural heritage (Colao et al 2005)
216 Conservation history
Wall paintings are an integral part of monuments and sites and should be preserved
in situ Many of the problems affecting wall paintings are linked to the poor condition of
the building or structure its improper use lack of maintenance frequent repairs and
alterations Also frequent restorations unnecessary uncovering and use of inappropriate
methods and materials can result in irreparable damage Substandard and inadequate
practices and professional qualifications have led to unfortunate results It is for this reason
that an appropriate document covering the principles of proper conservation-restoration of
wall paintings is necessary
The Venice Charter (1964) has provided general principles for the conservation-
restoration of cultural heritage The Amsterdam Declaration (1975) introducing the
concept of integrated conservation and the Nara Document on Authenticity (1994) dealing
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
35 Review of Literature
with cultural diversity have expanded these principles Taking into account these and
additional relevant contributions such as the ICOM-CC Code of Ethics (1984) Document
of Pavia (1997) and ECCO Professional Guidelines (1997) the aim of this document is
to provide more specific principles for the protection preservation and the conservation
restoration of wall paintings This document therefore reflects basic and universally
applicable principles and practices and does not take into account particular problems of
regions or countries which can be supplemented at regional and national level by
providing further recommendations where necessary
217 Preservation techniques of the mural paintings
The removal of fat salts varnishes and pollutants from the surfaces of the works
of art are mostly done by chemical and mechanical methods At the end of the 19th
century the practices of restoration methods that do not inhibit further future interventions
was considered acceptable During the 1960s several chemicals such as polymeric resins
were synthesized and applied as a consolidation or protection agents The accepted idea
was that these substances could be removed at any time leaving a completely unaltered
substrate On the basis of origin archaeological objects can be classified as follows
(Carretti 2005)
1 Inorganic It includes siliceous and nonsiliceous materials Archaeological materials
produced from stones terracotta ceramics and glass can be included under siliceous
materials whereas objects made of metals can be included under nonsiliceous inorganic
materials Again metal objects can be classified as ferrous metals and non-ferrous metals
Objects made of iron are termed as ferrous metal objects whereas metal objects made from
other than iron is termed as non-ferrous metal objects
2 Organic It includes archival and anthropological materials Again archival materials
include paper bhojapatra tadapatra textiles wooden objects miniature paintings whereas
anthropological objects include bone and ivory leather feather and fur etc
In the past restoration of paintings and other old artwork often involved application
of acrylic resins to consolidate and protect them One of the most important tasks for
modern restorers is thus to remove these layers because it turns out that acrylic resins not
only by drastically changing the optics of the treated artwork but in many cases they
accelerate their degradation The scientists use an oil-in-water microemulsion with the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
36 Review of Literature
organic solvent para-xylene as the oil component The matrix makes the cleaning agent
viscous so that it cannot enter very far into the pores of a painting (Carretti 2005)
Nanoparticle treatment is the logical evolution of the Ferroni-Dini method
Dispersions of kinetically stable Ca (OH)2 nanoparticles in non-aqueous solvents solved
most of the drawbacks of the microsized powders Stable dispersions of calcium hydroxide
have been successfully applied (replacing polymers) as fixatives to re-adhere lifted paint
layers during many restoration workshops in Italy and in Europe as a consolidant The
FerronindashDini method (two steps the application of a saturated solution of ammonium
carbonate (NH4)2CO3 and the treatment with a barium hydroxide solution Ba(OH)2 also
called the barium method has long been the acknowledged method for the removal of
salts that threaten paintings reinforcing at the same time the porous structure However
commercially available carbonates and hydroxide powders have dimensions of several
micrometres much larger than the pores on the paint surface This means they donrsquot
penetrate the painting well and there is also a risk of damaging the artwork by a white
glaze forming on the surface (Berger 2006) Restoration should provide the reinforcement
of the porous structure and the consolidation of the surface layer of arte facts A few
simple principles can be considered to define the most appropriate restoration method
1) The treatment should be reversible so that one can revert to the original status of the
work of art at any desired time
2) All the applied chemicals must ensure the maximum durability and the chemical
inertness
3) The applied chemicals must invert the degradation processes without altering the
chemical composition of the artefacts and their physico-chemical and mechanical
properties (Baglioni 2006)
218 Commercial preservative used for preservation of mural paintings
Cleaning was done using soft brushes vacuum cleaner and Gumma paine (dough)
a natural latex sponge Areas near the window were very dirty with black soot and were
cleaned with micro fibrous cloths moistened with synperonic N (surfactant alkyl phenol
ethoxylate based on nonyl phenol) and neutralized with clean water In several places the
paint layers had separated from the substrate (exfoli-ation) In that cases loose paint flakes
were stuck back using Paraloid B72 (10 solution in ethanol) as sparingly as possible
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
37 Review of Literature
Paraloid was injected with syringe behind the exfoliated area twice pushed and held back
with Melinex (polyester film) until fixed on the third application (Bionda et al 2002)
In a period of significant growth of molds and intensive efforts to stop the mold
contamination some of the lines of certain paintings were obscured or faded Solutions of
ethanol formalin 91 and Thiabendazole (TBZ) were used but they were not very
effective Para-formaldehyde fumigation was adopted beginning in 1981 to establish an
emergency treatment sensitivity of microorganisms from studied samples was tested
against Desogen by adding 1-3 (v v) in serial dilutions The best concentration
3 (vv) was applied with a brush to prevent spreading of the spores In order to overcome
the problem of fungal attack suitable fungicides carbendizeme or kiroxy-I or 5 solute of
N formaldehyde can be used Shellac solution in spirit or 2 solution of polyvinaycletate
in toluene can be used as preservative and consolidantsTo control insect and fungal attack
fumigants like pyrethrum DDT or 5 solution of sodium penta chlorophenate in kerosene
oil 2 to 5 solution of PVA in toluene or 2 to 5 solution of paraloid B-72 in toluene or
acetone be used (Miura 2009) Microclimatic conditions constitute a critical factor in the
conservation of cave paintings The unstable microclimatic condition is one of the factors
that always affect the state of conservation of mural paintings In the environmental-
monument system knowledge of the functional environment and climatic conditions of the
surroundings are necessary for the identification of causes of decay (Singh 2011)
Furthermore the risk of formation of indoor bioaerosols in residential and public
buildings (offices schools museums etc) has attracted interest in the last years due to
socio-economic as well as sanitary reasons (Ripka 2005) Thus it is important in aspects of
health and maintenance of Cultural Heritage to analyse the complete microflora to further
develop biocides for harmful microorganisms and methods for restoration of damaged
objects of art The biocidal testing was carried out on one representative algal species of
the two classes of algae viz Chlorococcum sp (green) and Chroococcus sp (blue-green)
found to be common in all the samples Efficiency tests were carried out both in liquid as
well as solid media containing algal suspensions by adding a biocide solution of known
concentration and determining the growth of the microorganism after the incubation
period The biocides used for the past studies were
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
30 Review of Literature
the first supply of organic matter The death and lysis of such bacteria promotes the
secondary settlement of heterotrophic bacteria and fungal populations (Calvo et al 1991)
Bacteria may derive from plants or pollen as many sequences obtained in this study
gave high score similarities with bacteria isolated from plants like Moraxella osloensis
Enterobacter cloace Enterobacter agglomerans and Pantoea endophytica Bacteria may
also derive from animal faeces like flies Bacillus Pseudomonas Aeromonas and Panteoa
(Ripka 2005) As Lazar and Dumitru (1973) reported studying mural paintings in a
Romanian monastery the genera Bacillus Arthrobacter and Pseudomonas have been
proved to produce salt efflorescences and were even considered to cause the blanching
phenomenon of frescoes (Jimenez et al 2000) Predominant bacterial genera are Bacillus
Streptomyces Arthrobacter Micrococcus and Pseudomonas [Weirich (1989)
Tate et al (1990) Arroyo et al (1997) Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
B) Fungi
It may be concluded that there is wide variety of fungal forms present on mural
paintings but Aspergillus and Alternaria were found dominating from all the experimental
sites next to them were Cladosporium Drechestera Fusarium Curvularia Chaetomium
Memnoniella Mycelia sterelai Pencillium Emericella Stachybotrytis Trichoderma
Phoma Monodictys Humicola and Epicoccum (Garg et al 1995)
The fungal genera most commonly found in lists of isolated taxa given in literature
are Alternaria Aspergillus Chaetomium Cladosporium Fusarium Penicillium and
Verticullum [Weirich (1989) Tate et al (1990) Guglielminetti et al (1994)
Garg et al (1995) Berner et al (1997) Ciferri (1999)] Some fungi having hard fruiting
bodies represented by sclerotia pycnidia perithecia cleistothecia and stroma could
organize themselves inside the painted layer Many fungal forms having such structures
were identified from our experimental sites viz Emericella nidulans A flavus
Chaetomium sp and Phoma sp etc These structures with little increase in humidity may
cause swelling in the paint film (Garg 1995)
Strains of species of Alternaria and Cladosporium both of them identified on the
mural paintings of the Palace of Schoumlnbrunn are the most common genera isolated from
stone and mural paintings in indoor environments with standard cultivation methods
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
31 Review of Literature
(Ventosa 2004) Saprophytic species of the genus Cladosporium are among the most
abundant fungi isolated in saltern samples Commonly isolated Cyanobacteria belong to
Nostoc and eukaryotic algae to Lyngbya and members of the Chlorophyceae such as
Chlorella Pseudococcomyxa and Pseudopleurococcus [Gorbushina et al (1987)
Calvo et al (1993) Arino et al (1996)]
They grow optimally on media with low water activity due to high salt or sugar
concentrations seem to propagate 70 vegetatively in the salterns and are thus
halotolerantosmotolerant species rather than simple flush-through occurrences
Cladiosporum herbarum was frequently isolated from hypersaline waters dead and dying
plant material air soil food fruit cereals paint and textiles (Ventosa 2004)
C) Algae
Most of the painted areas in temperature climate became covered with green algae
(Pleurococcus Protococcus and Trentopholia) while under tropical conditions blue green
algae of the genera Oscillatoria and Sytonema predominated (Garg 1995) The main
factors which contribute to the growth of algae on wall paintings are the presence of
moisture in the plaster as well as availability of visible light These conditions are quite
prevalent in the tropical climate but in temperature regions also algal growth on wall
paintings have been reported [Tonolo et al (1961) Pietrini et al (1991)]
D) Actinomycetes
Usually literature refers to specific aspects eg the occurrence of cyanobacteria
and algae in caves with natural openings to sunlight or those with artificial lighting fungi
and so forth Actinomycetes have been considered to be mainly confined to soils where
they find their natural habitat but despite intensive studies there are still many gaps in our
knowledge of the role played by actinomycetes in soil processes and biodegrations of
murals cave paintings (Groth et al 1999) In addition halophilic bacteria actinomycetes
and cyanobacteria are also capable of growing on salt-affected mural paintings
(Karbowska 2003)
Monte and Ferrari (1993) reviewed the mechanisms of biodeterioration in tombs
and underground churches The role of actinomycetes in the deterioration of frescoes in
hypogean environments was stressed by Agarossi et al (1985) Monte and Ferrari (1993)
Giacobini et al (1987) described the serious damage suffered by a whole series of famous
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
32 Review of Literature
frescoes in underground environments Actinomycetes were isolated from these mural
paintings located in crypts caves and tombs About 200 strains of actinomycetes were
isolated 60 of which were identified The most frequent species were Streptomyces albus
S cinereoruber S griseolus S vinaceus and some members of the Nocardia genus
Heterotrophic bacteria and actinomycetes were the most abundant microorganisms
on the frescoes of Etruscan tombs (Agarossi et al 1985) Bettini et al (1977) studied
some of the oldest Etruscan tombs (7th to 4th century BC) and found white-grey patinas
and spots from streptomycetes in the mural paintings They related the biodeterioration to
the microclimatic conditions (eg lower temperatures high RH) Monte and Ferrari (1993)
considered that colonization of the mural paintings was the result of selective competitive
and inhibitory dynamics among different microorganisms under different and changing
environmental conditions The pigments excreted by some actinomycetes were responsible
for the violet stains found on the walls of tombs in Tarquinia Similar stains were observed
in one of the Roman tombs the Circular Mausoleum the Necropolis of Carmona Spain
from which a Streptomyces sp producing violet pigments in culture media was isolated
214 Identification of biodeteriogens
The possibility of pigments and biodeteriogens identification in frescos and stone
monitoring is offered mostly by vibrational spectroscopy infrared thermography laser
induced fluorescence (LIF) laser induced breakdown spectroscopy (LIBS) XRF (X-Ray
Fluorescence) IR and UV emission Among them laser based methods allowing for in
situ or remote characterization of artwork surface were applied successfully for
prospecting diagnosis and maintenance (Colao et al 2005) The rep-PCR fingerprinting
of the isolates allowed determination of their genotypic diversity Studies that have
compared rep-PCR genomic fingerprint analysis with DNAndashDNA relatedness studies have
shown that the two techniques yield results that are in close agreement [Nick et al (1999)
Rademaker et al (2000)] These studies therefore suggest that rep-PCR fingerprinting can
be used as a genomic screening method to differentiate at the species level and to select
representatives for DNAndashDNA reassociation experiments (Heymann et al 2003)
The characterisation of bacteria was for example often limited to isolation from
group-specific media followed by microscopy [Sorlini et al (1987) Weirich (1989)
Tate et al (1990) and in more recent studies to morphological and physiological
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
33 Review of Literature
characteristics including miniaturised and automated systems such as API and BIOLOG
[Arroyo et al (1997) Jimmenez et al (2000) and Laiz et al (2000)] or to
chemotaxonomic characteristics [Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
Wagner et al (1994) demonstrated that conventional microbiological efforts can
fail to isolate all microorganisms present in natural samples DNA-based techniques used
to identify microorganisms have revealed only a smaller fraction of bacteria isolated from
artworks (Ward et al 1990 Rolleke et al 1996) Bacterial identification using molecular
techniques especially those including the sequencing of genes coding for ribosomal
16S rRNA is very important to study bacterial communities found on artefacts One such
method is Denaturing Gradient Gel Electrophoresis (DGGE) of PCR-amplified gene
fragments coding for rRNA (Muyzer et al 1993) that allows the separation of partial
16S rDNA amplified fragments of identical length but different sequence due to their
different melting behaviour in a gel system containing a gradient of denaturants
(Jimenez 2003)
Total genomic DNA was purified for 16S rRNA gene sequencing and rep-PCR
using a slight modification of the method of Pitcher et al (1989) as described by
Heyndrickx et al (1996) rep-PCR genomic fingerprinting was performed with the REP-
and (GTG)5 primers (Versalovic et al 1994) using the PCR conditions described
previously by Rademaker et al (1997) Electrophoresis and pattern analysis were further
performed as described by Heyrman et al (2003) 16S rRNA gene sequencing and
phylogenetic analysis were performed as described by Heyrman and Swings (2001)
Phylogenetic trees were constructed using the BioNumerics software (Applied Maths) by
applying the neighbour-joining and maximum-parsimony methods on a multiple alignment
similarity matrix The stability of relationships was assessed by a bootstrap analysis of
1000 datasets For determination of the G+C content and levels of DNAndashDNA
hybridization approximately 1 g biomass was harvested from agar plates DNA was
purified by using a combination of the protocols of Marmur (1961) and
Pitcher et al (1989) as described by Logan et al (2000) The G+C content of the DNA
was determined by HPLC (Mesbah et al 1989) using the further specifications given by
Logan et al (2000) DNAndashDNA hybridization experiments were performed using a
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
34 Review of Literature
modification of the microplate method of Ezaki et al (1989) as described by
Willems et al (2001)
215 Preservation and conservation
Nowadays the conservation and preservation of our cultural heritage is one of the
world main concerns particularly in Europe The increasing need for non-destructive
investigation tools has become a major issue as sampling is in most cases restricted in
view of the value or the uniqueness of the object Artworks as wall paintings in buildings
and monuments of historical interest are affected by environment physical (temperature
and humidity) and biological factors (biodeteriogens) and by human (pollutant releases)
impact and therefore modified over the time The term ldquoconservationrdquo may have many
different meanings in different fields Every intervention directed to the restoration and
safeguard of works of art is commonly considered as a conservation treatment For
example conservation can involve the cleaning procedures set up by chemists or the photo
documentation of the preservation of historical memory For the appropriate conservation
of works of art even the lighting systems in a museum or the control of the visitorrsquos
movements in a site should be monitored Chemical degradation which induces the flaking
of paintings and deterioration from rain wind dust and other environmental causes is
mainly responsible for the weakening of the porous structure and the surface layers of the
materials used in works of cultural heritage (Colao et al 2005)
216 Conservation history
Wall paintings are an integral part of monuments and sites and should be preserved
in situ Many of the problems affecting wall paintings are linked to the poor condition of
the building or structure its improper use lack of maintenance frequent repairs and
alterations Also frequent restorations unnecessary uncovering and use of inappropriate
methods and materials can result in irreparable damage Substandard and inadequate
practices and professional qualifications have led to unfortunate results It is for this reason
that an appropriate document covering the principles of proper conservation-restoration of
wall paintings is necessary
The Venice Charter (1964) has provided general principles for the conservation-
restoration of cultural heritage The Amsterdam Declaration (1975) introducing the
concept of integrated conservation and the Nara Document on Authenticity (1994) dealing
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
35 Review of Literature
with cultural diversity have expanded these principles Taking into account these and
additional relevant contributions such as the ICOM-CC Code of Ethics (1984) Document
of Pavia (1997) and ECCO Professional Guidelines (1997) the aim of this document is
to provide more specific principles for the protection preservation and the conservation
restoration of wall paintings This document therefore reflects basic and universally
applicable principles and practices and does not take into account particular problems of
regions or countries which can be supplemented at regional and national level by
providing further recommendations where necessary
217 Preservation techniques of the mural paintings
The removal of fat salts varnishes and pollutants from the surfaces of the works
of art are mostly done by chemical and mechanical methods At the end of the 19th
century the practices of restoration methods that do not inhibit further future interventions
was considered acceptable During the 1960s several chemicals such as polymeric resins
were synthesized and applied as a consolidation or protection agents The accepted idea
was that these substances could be removed at any time leaving a completely unaltered
substrate On the basis of origin archaeological objects can be classified as follows
(Carretti 2005)
1 Inorganic It includes siliceous and nonsiliceous materials Archaeological materials
produced from stones terracotta ceramics and glass can be included under siliceous
materials whereas objects made of metals can be included under nonsiliceous inorganic
materials Again metal objects can be classified as ferrous metals and non-ferrous metals
Objects made of iron are termed as ferrous metal objects whereas metal objects made from
other than iron is termed as non-ferrous metal objects
2 Organic It includes archival and anthropological materials Again archival materials
include paper bhojapatra tadapatra textiles wooden objects miniature paintings whereas
anthropological objects include bone and ivory leather feather and fur etc
In the past restoration of paintings and other old artwork often involved application
of acrylic resins to consolidate and protect them One of the most important tasks for
modern restorers is thus to remove these layers because it turns out that acrylic resins not
only by drastically changing the optics of the treated artwork but in many cases they
accelerate their degradation The scientists use an oil-in-water microemulsion with the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
36 Review of Literature
organic solvent para-xylene as the oil component The matrix makes the cleaning agent
viscous so that it cannot enter very far into the pores of a painting (Carretti 2005)
Nanoparticle treatment is the logical evolution of the Ferroni-Dini method
Dispersions of kinetically stable Ca (OH)2 nanoparticles in non-aqueous solvents solved
most of the drawbacks of the microsized powders Stable dispersions of calcium hydroxide
have been successfully applied (replacing polymers) as fixatives to re-adhere lifted paint
layers during many restoration workshops in Italy and in Europe as a consolidant The
FerronindashDini method (two steps the application of a saturated solution of ammonium
carbonate (NH4)2CO3 and the treatment with a barium hydroxide solution Ba(OH)2 also
called the barium method has long been the acknowledged method for the removal of
salts that threaten paintings reinforcing at the same time the porous structure However
commercially available carbonates and hydroxide powders have dimensions of several
micrometres much larger than the pores on the paint surface This means they donrsquot
penetrate the painting well and there is also a risk of damaging the artwork by a white
glaze forming on the surface (Berger 2006) Restoration should provide the reinforcement
of the porous structure and the consolidation of the surface layer of arte facts A few
simple principles can be considered to define the most appropriate restoration method
1) The treatment should be reversible so that one can revert to the original status of the
work of art at any desired time
2) All the applied chemicals must ensure the maximum durability and the chemical
inertness
3) The applied chemicals must invert the degradation processes without altering the
chemical composition of the artefacts and their physico-chemical and mechanical
properties (Baglioni 2006)
218 Commercial preservative used for preservation of mural paintings
Cleaning was done using soft brushes vacuum cleaner and Gumma paine (dough)
a natural latex sponge Areas near the window were very dirty with black soot and were
cleaned with micro fibrous cloths moistened with synperonic N (surfactant alkyl phenol
ethoxylate based on nonyl phenol) and neutralized with clean water In several places the
paint layers had separated from the substrate (exfoli-ation) In that cases loose paint flakes
were stuck back using Paraloid B72 (10 solution in ethanol) as sparingly as possible
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
37 Review of Literature
Paraloid was injected with syringe behind the exfoliated area twice pushed and held back
with Melinex (polyester film) until fixed on the third application (Bionda et al 2002)
In a period of significant growth of molds and intensive efforts to stop the mold
contamination some of the lines of certain paintings were obscured or faded Solutions of
ethanol formalin 91 and Thiabendazole (TBZ) were used but they were not very
effective Para-formaldehyde fumigation was adopted beginning in 1981 to establish an
emergency treatment sensitivity of microorganisms from studied samples was tested
against Desogen by adding 1-3 (v v) in serial dilutions The best concentration
3 (vv) was applied with a brush to prevent spreading of the spores In order to overcome
the problem of fungal attack suitable fungicides carbendizeme or kiroxy-I or 5 solute of
N formaldehyde can be used Shellac solution in spirit or 2 solution of polyvinaycletate
in toluene can be used as preservative and consolidantsTo control insect and fungal attack
fumigants like pyrethrum DDT or 5 solution of sodium penta chlorophenate in kerosene
oil 2 to 5 solution of PVA in toluene or 2 to 5 solution of paraloid B-72 in toluene or
acetone be used (Miura 2009) Microclimatic conditions constitute a critical factor in the
conservation of cave paintings The unstable microclimatic condition is one of the factors
that always affect the state of conservation of mural paintings In the environmental-
monument system knowledge of the functional environment and climatic conditions of the
surroundings are necessary for the identification of causes of decay (Singh 2011)
Furthermore the risk of formation of indoor bioaerosols in residential and public
buildings (offices schools museums etc) has attracted interest in the last years due to
socio-economic as well as sanitary reasons (Ripka 2005) Thus it is important in aspects of
health and maintenance of Cultural Heritage to analyse the complete microflora to further
develop biocides for harmful microorganisms and methods for restoration of damaged
objects of art The biocidal testing was carried out on one representative algal species of
the two classes of algae viz Chlorococcum sp (green) and Chroococcus sp (blue-green)
found to be common in all the samples Efficiency tests were carried out both in liquid as
well as solid media containing algal suspensions by adding a biocide solution of known
concentration and determining the growth of the microorganism after the incubation
period The biocides used for the past studies were
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
31 Review of Literature
(Ventosa 2004) Saprophytic species of the genus Cladosporium are among the most
abundant fungi isolated in saltern samples Commonly isolated Cyanobacteria belong to
Nostoc and eukaryotic algae to Lyngbya and members of the Chlorophyceae such as
Chlorella Pseudococcomyxa and Pseudopleurococcus [Gorbushina et al (1987)
Calvo et al (1993) Arino et al (1996)]
They grow optimally on media with low water activity due to high salt or sugar
concentrations seem to propagate 70 vegetatively in the salterns and are thus
halotolerantosmotolerant species rather than simple flush-through occurrences
Cladiosporum herbarum was frequently isolated from hypersaline waters dead and dying
plant material air soil food fruit cereals paint and textiles (Ventosa 2004)
C) Algae
Most of the painted areas in temperature climate became covered with green algae
(Pleurococcus Protococcus and Trentopholia) while under tropical conditions blue green
algae of the genera Oscillatoria and Sytonema predominated (Garg 1995) The main
factors which contribute to the growth of algae on wall paintings are the presence of
moisture in the plaster as well as availability of visible light These conditions are quite
prevalent in the tropical climate but in temperature regions also algal growth on wall
paintings have been reported [Tonolo et al (1961) Pietrini et al (1991)]
D) Actinomycetes
Usually literature refers to specific aspects eg the occurrence of cyanobacteria
and algae in caves with natural openings to sunlight or those with artificial lighting fungi
and so forth Actinomycetes have been considered to be mainly confined to soils where
they find their natural habitat but despite intensive studies there are still many gaps in our
knowledge of the role played by actinomycetes in soil processes and biodegrations of
murals cave paintings (Groth et al 1999) In addition halophilic bacteria actinomycetes
and cyanobacteria are also capable of growing on salt-affected mural paintings
(Karbowska 2003)
Monte and Ferrari (1993) reviewed the mechanisms of biodeterioration in tombs
and underground churches The role of actinomycetes in the deterioration of frescoes in
hypogean environments was stressed by Agarossi et al (1985) Monte and Ferrari (1993)
Giacobini et al (1987) described the serious damage suffered by a whole series of famous
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
32 Review of Literature
frescoes in underground environments Actinomycetes were isolated from these mural
paintings located in crypts caves and tombs About 200 strains of actinomycetes were
isolated 60 of which were identified The most frequent species were Streptomyces albus
S cinereoruber S griseolus S vinaceus and some members of the Nocardia genus
Heterotrophic bacteria and actinomycetes were the most abundant microorganisms
on the frescoes of Etruscan tombs (Agarossi et al 1985) Bettini et al (1977) studied
some of the oldest Etruscan tombs (7th to 4th century BC) and found white-grey patinas
and spots from streptomycetes in the mural paintings They related the biodeterioration to
the microclimatic conditions (eg lower temperatures high RH) Monte and Ferrari (1993)
considered that colonization of the mural paintings was the result of selective competitive
and inhibitory dynamics among different microorganisms under different and changing
environmental conditions The pigments excreted by some actinomycetes were responsible
for the violet stains found on the walls of tombs in Tarquinia Similar stains were observed
in one of the Roman tombs the Circular Mausoleum the Necropolis of Carmona Spain
from which a Streptomyces sp producing violet pigments in culture media was isolated
214 Identification of biodeteriogens
The possibility of pigments and biodeteriogens identification in frescos and stone
monitoring is offered mostly by vibrational spectroscopy infrared thermography laser
induced fluorescence (LIF) laser induced breakdown spectroscopy (LIBS) XRF (X-Ray
Fluorescence) IR and UV emission Among them laser based methods allowing for in
situ or remote characterization of artwork surface were applied successfully for
prospecting diagnosis and maintenance (Colao et al 2005) The rep-PCR fingerprinting
of the isolates allowed determination of their genotypic diversity Studies that have
compared rep-PCR genomic fingerprint analysis with DNAndashDNA relatedness studies have
shown that the two techniques yield results that are in close agreement [Nick et al (1999)
Rademaker et al (2000)] These studies therefore suggest that rep-PCR fingerprinting can
be used as a genomic screening method to differentiate at the species level and to select
representatives for DNAndashDNA reassociation experiments (Heymann et al 2003)
The characterisation of bacteria was for example often limited to isolation from
group-specific media followed by microscopy [Sorlini et al (1987) Weirich (1989)
Tate et al (1990) and in more recent studies to morphological and physiological
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
33 Review of Literature
characteristics including miniaturised and automated systems such as API and BIOLOG
[Arroyo et al (1997) Jimmenez et al (2000) and Laiz et al (2000)] or to
chemotaxonomic characteristics [Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
Wagner et al (1994) demonstrated that conventional microbiological efforts can
fail to isolate all microorganisms present in natural samples DNA-based techniques used
to identify microorganisms have revealed only a smaller fraction of bacteria isolated from
artworks (Ward et al 1990 Rolleke et al 1996) Bacterial identification using molecular
techniques especially those including the sequencing of genes coding for ribosomal
16S rRNA is very important to study bacterial communities found on artefacts One such
method is Denaturing Gradient Gel Electrophoresis (DGGE) of PCR-amplified gene
fragments coding for rRNA (Muyzer et al 1993) that allows the separation of partial
16S rDNA amplified fragments of identical length but different sequence due to their
different melting behaviour in a gel system containing a gradient of denaturants
(Jimenez 2003)
Total genomic DNA was purified for 16S rRNA gene sequencing and rep-PCR
using a slight modification of the method of Pitcher et al (1989) as described by
Heyndrickx et al (1996) rep-PCR genomic fingerprinting was performed with the REP-
and (GTG)5 primers (Versalovic et al 1994) using the PCR conditions described
previously by Rademaker et al (1997) Electrophoresis and pattern analysis were further
performed as described by Heyrman et al (2003) 16S rRNA gene sequencing and
phylogenetic analysis were performed as described by Heyrman and Swings (2001)
Phylogenetic trees were constructed using the BioNumerics software (Applied Maths) by
applying the neighbour-joining and maximum-parsimony methods on a multiple alignment
similarity matrix The stability of relationships was assessed by a bootstrap analysis of
1000 datasets For determination of the G+C content and levels of DNAndashDNA
hybridization approximately 1 g biomass was harvested from agar plates DNA was
purified by using a combination of the protocols of Marmur (1961) and
Pitcher et al (1989) as described by Logan et al (2000) The G+C content of the DNA
was determined by HPLC (Mesbah et al 1989) using the further specifications given by
Logan et al (2000) DNAndashDNA hybridization experiments were performed using a
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
34 Review of Literature
modification of the microplate method of Ezaki et al (1989) as described by
Willems et al (2001)
215 Preservation and conservation
Nowadays the conservation and preservation of our cultural heritage is one of the
world main concerns particularly in Europe The increasing need for non-destructive
investigation tools has become a major issue as sampling is in most cases restricted in
view of the value or the uniqueness of the object Artworks as wall paintings in buildings
and monuments of historical interest are affected by environment physical (temperature
and humidity) and biological factors (biodeteriogens) and by human (pollutant releases)
impact and therefore modified over the time The term ldquoconservationrdquo may have many
different meanings in different fields Every intervention directed to the restoration and
safeguard of works of art is commonly considered as a conservation treatment For
example conservation can involve the cleaning procedures set up by chemists or the photo
documentation of the preservation of historical memory For the appropriate conservation
of works of art even the lighting systems in a museum or the control of the visitorrsquos
movements in a site should be monitored Chemical degradation which induces the flaking
of paintings and deterioration from rain wind dust and other environmental causes is
mainly responsible for the weakening of the porous structure and the surface layers of the
materials used in works of cultural heritage (Colao et al 2005)
216 Conservation history
Wall paintings are an integral part of monuments and sites and should be preserved
in situ Many of the problems affecting wall paintings are linked to the poor condition of
the building or structure its improper use lack of maintenance frequent repairs and
alterations Also frequent restorations unnecessary uncovering and use of inappropriate
methods and materials can result in irreparable damage Substandard and inadequate
practices and professional qualifications have led to unfortunate results It is for this reason
that an appropriate document covering the principles of proper conservation-restoration of
wall paintings is necessary
The Venice Charter (1964) has provided general principles for the conservation-
restoration of cultural heritage The Amsterdam Declaration (1975) introducing the
concept of integrated conservation and the Nara Document on Authenticity (1994) dealing
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
35 Review of Literature
with cultural diversity have expanded these principles Taking into account these and
additional relevant contributions such as the ICOM-CC Code of Ethics (1984) Document
of Pavia (1997) and ECCO Professional Guidelines (1997) the aim of this document is
to provide more specific principles for the protection preservation and the conservation
restoration of wall paintings This document therefore reflects basic and universally
applicable principles and practices and does not take into account particular problems of
regions or countries which can be supplemented at regional and national level by
providing further recommendations where necessary
217 Preservation techniques of the mural paintings
The removal of fat salts varnishes and pollutants from the surfaces of the works
of art are mostly done by chemical and mechanical methods At the end of the 19th
century the practices of restoration methods that do not inhibit further future interventions
was considered acceptable During the 1960s several chemicals such as polymeric resins
were synthesized and applied as a consolidation or protection agents The accepted idea
was that these substances could be removed at any time leaving a completely unaltered
substrate On the basis of origin archaeological objects can be classified as follows
(Carretti 2005)
1 Inorganic It includes siliceous and nonsiliceous materials Archaeological materials
produced from stones terracotta ceramics and glass can be included under siliceous
materials whereas objects made of metals can be included under nonsiliceous inorganic
materials Again metal objects can be classified as ferrous metals and non-ferrous metals
Objects made of iron are termed as ferrous metal objects whereas metal objects made from
other than iron is termed as non-ferrous metal objects
2 Organic It includes archival and anthropological materials Again archival materials
include paper bhojapatra tadapatra textiles wooden objects miniature paintings whereas
anthropological objects include bone and ivory leather feather and fur etc
In the past restoration of paintings and other old artwork often involved application
of acrylic resins to consolidate and protect them One of the most important tasks for
modern restorers is thus to remove these layers because it turns out that acrylic resins not
only by drastically changing the optics of the treated artwork but in many cases they
accelerate their degradation The scientists use an oil-in-water microemulsion with the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
36 Review of Literature
organic solvent para-xylene as the oil component The matrix makes the cleaning agent
viscous so that it cannot enter very far into the pores of a painting (Carretti 2005)
Nanoparticle treatment is the logical evolution of the Ferroni-Dini method
Dispersions of kinetically stable Ca (OH)2 nanoparticles in non-aqueous solvents solved
most of the drawbacks of the microsized powders Stable dispersions of calcium hydroxide
have been successfully applied (replacing polymers) as fixatives to re-adhere lifted paint
layers during many restoration workshops in Italy and in Europe as a consolidant The
FerronindashDini method (two steps the application of a saturated solution of ammonium
carbonate (NH4)2CO3 and the treatment with a barium hydroxide solution Ba(OH)2 also
called the barium method has long been the acknowledged method for the removal of
salts that threaten paintings reinforcing at the same time the porous structure However
commercially available carbonates and hydroxide powders have dimensions of several
micrometres much larger than the pores on the paint surface This means they donrsquot
penetrate the painting well and there is also a risk of damaging the artwork by a white
glaze forming on the surface (Berger 2006) Restoration should provide the reinforcement
of the porous structure and the consolidation of the surface layer of arte facts A few
simple principles can be considered to define the most appropriate restoration method
1) The treatment should be reversible so that one can revert to the original status of the
work of art at any desired time
2) All the applied chemicals must ensure the maximum durability and the chemical
inertness
3) The applied chemicals must invert the degradation processes without altering the
chemical composition of the artefacts and their physico-chemical and mechanical
properties (Baglioni 2006)
218 Commercial preservative used for preservation of mural paintings
Cleaning was done using soft brushes vacuum cleaner and Gumma paine (dough)
a natural latex sponge Areas near the window were very dirty with black soot and were
cleaned with micro fibrous cloths moistened with synperonic N (surfactant alkyl phenol
ethoxylate based on nonyl phenol) and neutralized with clean water In several places the
paint layers had separated from the substrate (exfoli-ation) In that cases loose paint flakes
were stuck back using Paraloid B72 (10 solution in ethanol) as sparingly as possible
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
37 Review of Literature
Paraloid was injected with syringe behind the exfoliated area twice pushed and held back
with Melinex (polyester film) until fixed on the third application (Bionda et al 2002)
In a period of significant growth of molds and intensive efforts to stop the mold
contamination some of the lines of certain paintings were obscured or faded Solutions of
ethanol formalin 91 and Thiabendazole (TBZ) were used but they were not very
effective Para-formaldehyde fumigation was adopted beginning in 1981 to establish an
emergency treatment sensitivity of microorganisms from studied samples was tested
against Desogen by adding 1-3 (v v) in serial dilutions The best concentration
3 (vv) was applied with a brush to prevent spreading of the spores In order to overcome
the problem of fungal attack suitable fungicides carbendizeme or kiroxy-I or 5 solute of
N formaldehyde can be used Shellac solution in spirit or 2 solution of polyvinaycletate
in toluene can be used as preservative and consolidantsTo control insect and fungal attack
fumigants like pyrethrum DDT or 5 solution of sodium penta chlorophenate in kerosene
oil 2 to 5 solution of PVA in toluene or 2 to 5 solution of paraloid B-72 in toluene or
acetone be used (Miura 2009) Microclimatic conditions constitute a critical factor in the
conservation of cave paintings The unstable microclimatic condition is one of the factors
that always affect the state of conservation of mural paintings In the environmental-
monument system knowledge of the functional environment and climatic conditions of the
surroundings are necessary for the identification of causes of decay (Singh 2011)
Furthermore the risk of formation of indoor bioaerosols in residential and public
buildings (offices schools museums etc) has attracted interest in the last years due to
socio-economic as well as sanitary reasons (Ripka 2005) Thus it is important in aspects of
health and maintenance of Cultural Heritage to analyse the complete microflora to further
develop biocides for harmful microorganisms and methods for restoration of damaged
objects of art The biocidal testing was carried out on one representative algal species of
the two classes of algae viz Chlorococcum sp (green) and Chroococcus sp (blue-green)
found to be common in all the samples Efficiency tests were carried out both in liquid as
well as solid media containing algal suspensions by adding a biocide solution of known
concentration and determining the growth of the microorganism after the incubation
period The biocides used for the past studies were
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
32 Review of Literature
frescoes in underground environments Actinomycetes were isolated from these mural
paintings located in crypts caves and tombs About 200 strains of actinomycetes were
isolated 60 of which were identified The most frequent species were Streptomyces albus
S cinereoruber S griseolus S vinaceus and some members of the Nocardia genus
Heterotrophic bacteria and actinomycetes were the most abundant microorganisms
on the frescoes of Etruscan tombs (Agarossi et al 1985) Bettini et al (1977) studied
some of the oldest Etruscan tombs (7th to 4th century BC) and found white-grey patinas
and spots from streptomycetes in the mural paintings They related the biodeterioration to
the microclimatic conditions (eg lower temperatures high RH) Monte and Ferrari (1993)
considered that colonization of the mural paintings was the result of selective competitive
and inhibitory dynamics among different microorganisms under different and changing
environmental conditions The pigments excreted by some actinomycetes were responsible
for the violet stains found on the walls of tombs in Tarquinia Similar stains were observed
in one of the Roman tombs the Circular Mausoleum the Necropolis of Carmona Spain
from which a Streptomyces sp producing violet pigments in culture media was isolated
214 Identification of biodeteriogens
The possibility of pigments and biodeteriogens identification in frescos and stone
monitoring is offered mostly by vibrational spectroscopy infrared thermography laser
induced fluorescence (LIF) laser induced breakdown spectroscopy (LIBS) XRF (X-Ray
Fluorescence) IR and UV emission Among them laser based methods allowing for in
situ or remote characterization of artwork surface were applied successfully for
prospecting diagnosis and maintenance (Colao et al 2005) The rep-PCR fingerprinting
of the isolates allowed determination of their genotypic diversity Studies that have
compared rep-PCR genomic fingerprint analysis with DNAndashDNA relatedness studies have
shown that the two techniques yield results that are in close agreement [Nick et al (1999)
Rademaker et al (2000)] These studies therefore suggest that rep-PCR fingerprinting can
be used as a genomic screening method to differentiate at the species level and to select
representatives for DNAndashDNA reassociation experiments (Heymann et al 2003)
The characterisation of bacteria was for example often limited to isolation from
group-specific media followed by microscopy [Sorlini et al (1987) Weirich (1989)
Tate et al (1990) and in more recent studies to morphological and physiological
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
33 Review of Literature
characteristics including miniaturised and automated systems such as API and BIOLOG
[Arroyo et al (1997) Jimmenez et al (2000) and Laiz et al (2000)] or to
chemotaxonomic characteristics [Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
Wagner et al (1994) demonstrated that conventional microbiological efforts can
fail to isolate all microorganisms present in natural samples DNA-based techniques used
to identify microorganisms have revealed only a smaller fraction of bacteria isolated from
artworks (Ward et al 1990 Rolleke et al 1996) Bacterial identification using molecular
techniques especially those including the sequencing of genes coding for ribosomal
16S rRNA is very important to study bacterial communities found on artefacts One such
method is Denaturing Gradient Gel Electrophoresis (DGGE) of PCR-amplified gene
fragments coding for rRNA (Muyzer et al 1993) that allows the separation of partial
16S rDNA amplified fragments of identical length but different sequence due to their
different melting behaviour in a gel system containing a gradient of denaturants
(Jimenez 2003)
Total genomic DNA was purified for 16S rRNA gene sequencing and rep-PCR
using a slight modification of the method of Pitcher et al (1989) as described by
Heyndrickx et al (1996) rep-PCR genomic fingerprinting was performed with the REP-
and (GTG)5 primers (Versalovic et al 1994) using the PCR conditions described
previously by Rademaker et al (1997) Electrophoresis and pattern analysis were further
performed as described by Heyrman et al (2003) 16S rRNA gene sequencing and
phylogenetic analysis were performed as described by Heyrman and Swings (2001)
Phylogenetic trees were constructed using the BioNumerics software (Applied Maths) by
applying the neighbour-joining and maximum-parsimony methods on a multiple alignment
similarity matrix The stability of relationships was assessed by a bootstrap analysis of
1000 datasets For determination of the G+C content and levels of DNAndashDNA
hybridization approximately 1 g biomass was harvested from agar plates DNA was
purified by using a combination of the protocols of Marmur (1961) and
Pitcher et al (1989) as described by Logan et al (2000) The G+C content of the DNA
was determined by HPLC (Mesbah et al 1989) using the further specifications given by
Logan et al (2000) DNAndashDNA hybridization experiments were performed using a
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
34 Review of Literature
modification of the microplate method of Ezaki et al (1989) as described by
Willems et al (2001)
215 Preservation and conservation
Nowadays the conservation and preservation of our cultural heritage is one of the
world main concerns particularly in Europe The increasing need for non-destructive
investigation tools has become a major issue as sampling is in most cases restricted in
view of the value or the uniqueness of the object Artworks as wall paintings in buildings
and monuments of historical interest are affected by environment physical (temperature
and humidity) and biological factors (biodeteriogens) and by human (pollutant releases)
impact and therefore modified over the time The term ldquoconservationrdquo may have many
different meanings in different fields Every intervention directed to the restoration and
safeguard of works of art is commonly considered as a conservation treatment For
example conservation can involve the cleaning procedures set up by chemists or the photo
documentation of the preservation of historical memory For the appropriate conservation
of works of art even the lighting systems in a museum or the control of the visitorrsquos
movements in a site should be monitored Chemical degradation which induces the flaking
of paintings and deterioration from rain wind dust and other environmental causes is
mainly responsible for the weakening of the porous structure and the surface layers of the
materials used in works of cultural heritage (Colao et al 2005)
216 Conservation history
Wall paintings are an integral part of monuments and sites and should be preserved
in situ Many of the problems affecting wall paintings are linked to the poor condition of
the building or structure its improper use lack of maintenance frequent repairs and
alterations Also frequent restorations unnecessary uncovering and use of inappropriate
methods and materials can result in irreparable damage Substandard and inadequate
practices and professional qualifications have led to unfortunate results It is for this reason
that an appropriate document covering the principles of proper conservation-restoration of
wall paintings is necessary
The Venice Charter (1964) has provided general principles for the conservation-
restoration of cultural heritage The Amsterdam Declaration (1975) introducing the
concept of integrated conservation and the Nara Document on Authenticity (1994) dealing
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
35 Review of Literature
with cultural diversity have expanded these principles Taking into account these and
additional relevant contributions such as the ICOM-CC Code of Ethics (1984) Document
of Pavia (1997) and ECCO Professional Guidelines (1997) the aim of this document is
to provide more specific principles for the protection preservation and the conservation
restoration of wall paintings This document therefore reflects basic and universally
applicable principles and practices and does not take into account particular problems of
regions or countries which can be supplemented at regional and national level by
providing further recommendations where necessary
217 Preservation techniques of the mural paintings
The removal of fat salts varnishes and pollutants from the surfaces of the works
of art are mostly done by chemical and mechanical methods At the end of the 19th
century the practices of restoration methods that do not inhibit further future interventions
was considered acceptable During the 1960s several chemicals such as polymeric resins
were synthesized and applied as a consolidation or protection agents The accepted idea
was that these substances could be removed at any time leaving a completely unaltered
substrate On the basis of origin archaeological objects can be classified as follows
(Carretti 2005)
1 Inorganic It includes siliceous and nonsiliceous materials Archaeological materials
produced from stones terracotta ceramics and glass can be included under siliceous
materials whereas objects made of metals can be included under nonsiliceous inorganic
materials Again metal objects can be classified as ferrous metals and non-ferrous metals
Objects made of iron are termed as ferrous metal objects whereas metal objects made from
other than iron is termed as non-ferrous metal objects
2 Organic It includes archival and anthropological materials Again archival materials
include paper bhojapatra tadapatra textiles wooden objects miniature paintings whereas
anthropological objects include bone and ivory leather feather and fur etc
In the past restoration of paintings and other old artwork often involved application
of acrylic resins to consolidate and protect them One of the most important tasks for
modern restorers is thus to remove these layers because it turns out that acrylic resins not
only by drastically changing the optics of the treated artwork but in many cases they
accelerate their degradation The scientists use an oil-in-water microemulsion with the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
36 Review of Literature
organic solvent para-xylene as the oil component The matrix makes the cleaning agent
viscous so that it cannot enter very far into the pores of a painting (Carretti 2005)
Nanoparticle treatment is the logical evolution of the Ferroni-Dini method
Dispersions of kinetically stable Ca (OH)2 nanoparticles in non-aqueous solvents solved
most of the drawbacks of the microsized powders Stable dispersions of calcium hydroxide
have been successfully applied (replacing polymers) as fixatives to re-adhere lifted paint
layers during many restoration workshops in Italy and in Europe as a consolidant The
FerronindashDini method (two steps the application of a saturated solution of ammonium
carbonate (NH4)2CO3 and the treatment with a barium hydroxide solution Ba(OH)2 also
called the barium method has long been the acknowledged method for the removal of
salts that threaten paintings reinforcing at the same time the porous structure However
commercially available carbonates and hydroxide powders have dimensions of several
micrometres much larger than the pores on the paint surface This means they donrsquot
penetrate the painting well and there is also a risk of damaging the artwork by a white
glaze forming on the surface (Berger 2006) Restoration should provide the reinforcement
of the porous structure and the consolidation of the surface layer of arte facts A few
simple principles can be considered to define the most appropriate restoration method
1) The treatment should be reversible so that one can revert to the original status of the
work of art at any desired time
2) All the applied chemicals must ensure the maximum durability and the chemical
inertness
3) The applied chemicals must invert the degradation processes without altering the
chemical composition of the artefacts and their physico-chemical and mechanical
properties (Baglioni 2006)
218 Commercial preservative used for preservation of mural paintings
Cleaning was done using soft brushes vacuum cleaner and Gumma paine (dough)
a natural latex sponge Areas near the window were very dirty with black soot and were
cleaned with micro fibrous cloths moistened with synperonic N (surfactant alkyl phenol
ethoxylate based on nonyl phenol) and neutralized with clean water In several places the
paint layers had separated from the substrate (exfoli-ation) In that cases loose paint flakes
were stuck back using Paraloid B72 (10 solution in ethanol) as sparingly as possible
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
37 Review of Literature
Paraloid was injected with syringe behind the exfoliated area twice pushed and held back
with Melinex (polyester film) until fixed on the third application (Bionda et al 2002)
In a period of significant growth of molds and intensive efforts to stop the mold
contamination some of the lines of certain paintings were obscured or faded Solutions of
ethanol formalin 91 and Thiabendazole (TBZ) were used but they were not very
effective Para-formaldehyde fumigation was adopted beginning in 1981 to establish an
emergency treatment sensitivity of microorganisms from studied samples was tested
against Desogen by adding 1-3 (v v) in serial dilutions The best concentration
3 (vv) was applied with a brush to prevent spreading of the spores In order to overcome
the problem of fungal attack suitable fungicides carbendizeme or kiroxy-I or 5 solute of
N formaldehyde can be used Shellac solution in spirit or 2 solution of polyvinaycletate
in toluene can be used as preservative and consolidantsTo control insect and fungal attack
fumigants like pyrethrum DDT or 5 solution of sodium penta chlorophenate in kerosene
oil 2 to 5 solution of PVA in toluene or 2 to 5 solution of paraloid B-72 in toluene or
acetone be used (Miura 2009) Microclimatic conditions constitute a critical factor in the
conservation of cave paintings The unstable microclimatic condition is one of the factors
that always affect the state of conservation of mural paintings In the environmental-
monument system knowledge of the functional environment and climatic conditions of the
surroundings are necessary for the identification of causes of decay (Singh 2011)
Furthermore the risk of formation of indoor bioaerosols in residential and public
buildings (offices schools museums etc) has attracted interest in the last years due to
socio-economic as well as sanitary reasons (Ripka 2005) Thus it is important in aspects of
health and maintenance of Cultural Heritage to analyse the complete microflora to further
develop biocides for harmful microorganisms and methods for restoration of damaged
objects of art The biocidal testing was carried out on one representative algal species of
the two classes of algae viz Chlorococcum sp (green) and Chroococcus sp (blue-green)
found to be common in all the samples Efficiency tests were carried out both in liquid as
well as solid media containing algal suspensions by adding a biocide solution of known
concentration and determining the growth of the microorganism after the incubation
period The biocides used for the past studies were
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
33 Review of Literature
characteristics including miniaturised and automated systems such as API and BIOLOG
[Arroyo et al (1997) Jimmenez et al (2000) and Laiz et al (2000)] or to
chemotaxonomic characteristics [Gonzalez et al (1999) Groth et al (1999)
Jimenez et al (2000)]
Wagner et al (1994) demonstrated that conventional microbiological efforts can
fail to isolate all microorganisms present in natural samples DNA-based techniques used
to identify microorganisms have revealed only a smaller fraction of bacteria isolated from
artworks (Ward et al 1990 Rolleke et al 1996) Bacterial identification using molecular
techniques especially those including the sequencing of genes coding for ribosomal
16S rRNA is very important to study bacterial communities found on artefacts One such
method is Denaturing Gradient Gel Electrophoresis (DGGE) of PCR-amplified gene
fragments coding for rRNA (Muyzer et al 1993) that allows the separation of partial
16S rDNA amplified fragments of identical length but different sequence due to their
different melting behaviour in a gel system containing a gradient of denaturants
(Jimenez 2003)
Total genomic DNA was purified for 16S rRNA gene sequencing and rep-PCR
using a slight modification of the method of Pitcher et al (1989) as described by
Heyndrickx et al (1996) rep-PCR genomic fingerprinting was performed with the REP-
and (GTG)5 primers (Versalovic et al 1994) using the PCR conditions described
previously by Rademaker et al (1997) Electrophoresis and pattern analysis were further
performed as described by Heyrman et al (2003) 16S rRNA gene sequencing and
phylogenetic analysis were performed as described by Heyrman and Swings (2001)
Phylogenetic trees were constructed using the BioNumerics software (Applied Maths) by
applying the neighbour-joining and maximum-parsimony methods on a multiple alignment
similarity matrix The stability of relationships was assessed by a bootstrap analysis of
1000 datasets For determination of the G+C content and levels of DNAndashDNA
hybridization approximately 1 g biomass was harvested from agar plates DNA was
purified by using a combination of the protocols of Marmur (1961) and
Pitcher et al (1989) as described by Logan et al (2000) The G+C content of the DNA
was determined by HPLC (Mesbah et al 1989) using the further specifications given by
Logan et al (2000) DNAndashDNA hybridization experiments were performed using a
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
34 Review of Literature
modification of the microplate method of Ezaki et al (1989) as described by
Willems et al (2001)
215 Preservation and conservation
Nowadays the conservation and preservation of our cultural heritage is one of the
world main concerns particularly in Europe The increasing need for non-destructive
investigation tools has become a major issue as sampling is in most cases restricted in
view of the value or the uniqueness of the object Artworks as wall paintings in buildings
and monuments of historical interest are affected by environment physical (temperature
and humidity) and biological factors (biodeteriogens) and by human (pollutant releases)
impact and therefore modified over the time The term ldquoconservationrdquo may have many
different meanings in different fields Every intervention directed to the restoration and
safeguard of works of art is commonly considered as a conservation treatment For
example conservation can involve the cleaning procedures set up by chemists or the photo
documentation of the preservation of historical memory For the appropriate conservation
of works of art even the lighting systems in a museum or the control of the visitorrsquos
movements in a site should be monitored Chemical degradation which induces the flaking
of paintings and deterioration from rain wind dust and other environmental causes is
mainly responsible for the weakening of the porous structure and the surface layers of the
materials used in works of cultural heritage (Colao et al 2005)
216 Conservation history
Wall paintings are an integral part of monuments and sites and should be preserved
in situ Many of the problems affecting wall paintings are linked to the poor condition of
the building or structure its improper use lack of maintenance frequent repairs and
alterations Also frequent restorations unnecessary uncovering and use of inappropriate
methods and materials can result in irreparable damage Substandard and inadequate
practices and professional qualifications have led to unfortunate results It is for this reason
that an appropriate document covering the principles of proper conservation-restoration of
wall paintings is necessary
The Venice Charter (1964) has provided general principles for the conservation-
restoration of cultural heritage The Amsterdam Declaration (1975) introducing the
concept of integrated conservation and the Nara Document on Authenticity (1994) dealing
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
35 Review of Literature
with cultural diversity have expanded these principles Taking into account these and
additional relevant contributions such as the ICOM-CC Code of Ethics (1984) Document
of Pavia (1997) and ECCO Professional Guidelines (1997) the aim of this document is
to provide more specific principles for the protection preservation and the conservation
restoration of wall paintings This document therefore reflects basic and universally
applicable principles and practices and does not take into account particular problems of
regions or countries which can be supplemented at regional and national level by
providing further recommendations where necessary
217 Preservation techniques of the mural paintings
The removal of fat salts varnishes and pollutants from the surfaces of the works
of art are mostly done by chemical and mechanical methods At the end of the 19th
century the practices of restoration methods that do not inhibit further future interventions
was considered acceptable During the 1960s several chemicals such as polymeric resins
were synthesized and applied as a consolidation or protection agents The accepted idea
was that these substances could be removed at any time leaving a completely unaltered
substrate On the basis of origin archaeological objects can be classified as follows
(Carretti 2005)
1 Inorganic It includes siliceous and nonsiliceous materials Archaeological materials
produced from stones terracotta ceramics and glass can be included under siliceous
materials whereas objects made of metals can be included under nonsiliceous inorganic
materials Again metal objects can be classified as ferrous metals and non-ferrous metals
Objects made of iron are termed as ferrous metal objects whereas metal objects made from
other than iron is termed as non-ferrous metal objects
2 Organic It includes archival and anthropological materials Again archival materials
include paper bhojapatra tadapatra textiles wooden objects miniature paintings whereas
anthropological objects include bone and ivory leather feather and fur etc
In the past restoration of paintings and other old artwork often involved application
of acrylic resins to consolidate and protect them One of the most important tasks for
modern restorers is thus to remove these layers because it turns out that acrylic resins not
only by drastically changing the optics of the treated artwork but in many cases they
accelerate their degradation The scientists use an oil-in-water microemulsion with the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
36 Review of Literature
organic solvent para-xylene as the oil component The matrix makes the cleaning agent
viscous so that it cannot enter very far into the pores of a painting (Carretti 2005)
Nanoparticle treatment is the logical evolution of the Ferroni-Dini method
Dispersions of kinetically stable Ca (OH)2 nanoparticles in non-aqueous solvents solved
most of the drawbacks of the microsized powders Stable dispersions of calcium hydroxide
have been successfully applied (replacing polymers) as fixatives to re-adhere lifted paint
layers during many restoration workshops in Italy and in Europe as a consolidant The
FerronindashDini method (two steps the application of a saturated solution of ammonium
carbonate (NH4)2CO3 and the treatment with a barium hydroxide solution Ba(OH)2 also
called the barium method has long been the acknowledged method for the removal of
salts that threaten paintings reinforcing at the same time the porous structure However
commercially available carbonates and hydroxide powders have dimensions of several
micrometres much larger than the pores on the paint surface This means they donrsquot
penetrate the painting well and there is also a risk of damaging the artwork by a white
glaze forming on the surface (Berger 2006) Restoration should provide the reinforcement
of the porous structure and the consolidation of the surface layer of arte facts A few
simple principles can be considered to define the most appropriate restoration method
1) The treatment should be reversible so that one can revert to the original status of the
work of art at any desired time
2) All the applied chemicals must ensure the maximum durability and the chemical
inertness
3) The applied chemicals must invert the degradation processes without altering the
chemical composition of the artefacts and their physico-chemical and mechanical
properties (Baglioni 2006)
218 Commercial preservative used for preservation of mural paintings
Cleaning was done using soft brushes vacuum cleaner and Gumma paine (dough)
a natural latex sponge Areas near the window were very dirty with black soot and were
cleaned with micro fibrous cloths moistened with synperonic N (surfactant alkyl phenol
ethoxylate based on nonyl phenol) and neutralized with clean water In several places the
paint layers had separated from the substrate (exfoli-ation) In that cases loose paint flakes
were stuck back using Paraloid B72 (10 solution in ethanol) as sparingly as possible
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
37 Review of Literature
Paraloid was injected with syringe behind the exfoliated area twice pushed and held back
with Melinex (polyester film) until fixed on the third application (Bionda et al 2002)
In a period of significant growth of molds and intensive efforts to stop the mold
contamination some of the lines of certain paintings were obscured or faded Solutions of
ethanol formalin 91 and Thiabendazole (TBZ) were used but they were not very
effective Para-formaldehyde fumigation was adopted beginning in 1981 to establish an
emergency treatment sensitivity of microorganisms from studied samples was tested
against Desogen by adding 1-3 (v v) in serial dilutions The best concentration
3 (vv) was applied with a brush to prevent spreading of the spores In order to overcome
the problem of fungal attack suitable fungicides carbendizeme or kiroxy-I or 5 solute of
N formaldehyde can be used Shellac solution in spirit or 2 solution of polyvinaycletate
in toluene can be used as preservative and consolidantsTo control insect and fungal attack
fumigants like pyrethrum DDT or 5 solution of sodium penta chlorophenate in kerosene
oil 2 to 5 solution of PVA in toluene or 2 to 5 solution of paraloid B-72 in toluene or
acetone be used (Miura 2009) Microclimatic conditions constitute a critical factor in the
conservation of cave paintings The unstable microclimatic condition is one of the factors
that always affect the state of conservation of mural paintings In the environmental-
monument system knowledge of the functional environment and climatic conditions of the
surroundings are necessary for the identification of causes of decay (Singh 2011)
Furthermore the risk of formation of indoor bioaerosols in residential and public
buildings (offices schools museums etc) has attracted interest in the last years due to
socio-economic as well as sanitary reasons (Ripka 2005) Thus it is important in aspects of
health and maintenance of Cultural Heritage to analyse the complete microflora to further
develop biocides for harmful microorganisms and methods for restoration of damaged
objects of art The biocidal testing was carried out on one representative algal species of
the two classes of algae viz Chlorococcum sp (green) and Chroococcus sp (blue-green)
found to be common in all the samples Efficiency tests were carried out both in liquid as
well as solid media containing algal suspensions by adding a biocide solution of known
concentration and determining the growth of the microorganism after the incubation
period The biocides used for the past studies were
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
34 Review of Literature
modification of the microplate method of Ezaki et al (1989) as described by
Willems et al (2001)
215 Preservation and conservation
Nowadays the conservation and preservation of our cultural heritage is one of the
world main concerns particularly in Europe The increasing need for non-destructive
investigation tools has become a major issue as sampling is in most cases restricted in
view of the value or the uniqueness of the object Artworks as wall paintings in buildings
and monuments of historical interest are affected by environment physical (temperature
and humidity) and biological factors (biodeteriogens) and by human (pollutant releases)
impact and therefore modified over the time The term ldquoconservationrdquo may have many
different meanings in different fields Every intervention directed to the restoration and
safeguard of works of art is commonly considered as a conservation treatment For
example conservation can involve the cleaning procedures set up by chemists or the photo
documentation of the preservation of historical memory For the appropriate conservation
of works of art even the lighting systems in a museum or the control of the visitorrsquos
movements in a site should be monitored Chemical degradation which induces the flaking
of paintings and deterioration from rain wind dust and other environmental causes is
mainly responsible for the weakening of the porous structure and the surface layers of the
materials used in works of cultural heritage (Colao et al 2005)
216 Conservation history
Wall paintings are an integral part of monuments and sites and should be preserved
in situ Many of the problems affecting wall paintings are linked to the poor condition of
the building or structure its improper use lack of maintenance frequent repairs and
alterations Also frequent restorations unnecessary uncovering and use of inappropriate
methods and materials can result in irreparable damage Substandard and inadequate
practices and professional qualifications have led to unfortunate results It is for this reason
that an appropriate document covering the principles of proper conservation-restoration of
wall paintings is necessary
The Venice Charter (1964) has provided general principles for the conservation-
restoration of cultural heritage The Amsterdam Declaration (1975) introducing the
concept of integrated conservation and the Nara Document on Authenticity (1994) dealing
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
35 Review of Literature
with cultural diversity have expanded these principles Taking into account these and
additional relevant contributions such as the ICOM-CC Code of Ethics (1984) Document
of Pavia (1997) and ECCO Professional Guidelines (1997) the aim of this document is
to provide more specific principles for the protection preservation and the conservation
restoration of wall paintings This document therefore reflects basic and universally
applicable principles and practices and does not take into account particular problems of
regions or countries which can be supplemented at regional and national level by
providing further recommendations where necessary
217 Preservation techniques of the mural paintings
The removal of fat salts varnishes and pollutants from the surfaces of the works
of art are mostly done by chemical and mechanical methods At the end of the 19th
century the practices of restoration methods that do not inhibit further future interventions
was considered acceptable During the 1960s several chemicals such as polymeric resins
were synthesized and applied as a consolidation or protection agents The accepted idea
was that these substances could be removed at any time leaving a completely unaltered
substrate On the basis of origin archaeological objects can be classified as follows
(Carretti 2005)
1 Inorganic It includes siliceous and nonsiliceous materials Archaeological materials
produced from stones terracotta ceramics and glass can be included under siliceous
materials whereas objects made of metals can be included under nonsiliceous inorganic
materials Again metal objects can be classified as ferrous metals and non-ferrous metals
Objects made of iron are termed as ferrous metal objects whereas metal objects made from
other than iron is termed as non-ferrous metal objects
2 Organic It includes archival and anthropological materials Again archival materials
include paper bhojapatra tadapatra textiles wooden objects miniature paintings whereas
anthropological objects include bone and ivory leather feather and fur etc
In the past restoration of paintings and other old artwork often involved application
of acrylic resins to consolidate and protect them One of the most important tasks for
modern restorers is thus to remove these layers because it turns out that acrylic resins not
only by drastically changing the optics of the treated artwork but in many cases they
accelerate their degradation The scientists use an oil-in-water microemulsion with the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
36 Review of Literature
organic solvent para-xylene as the oil component The matrix makes the cleaning agent
viscous so that it cannot enter very far into the pores of a painting (Carretti 2005)
Nanoparticle treatment is the logical evolution of the Ferroni-Dini method
Dispersions of kinetically stable Ca (OH)2 nanoparticles in non-aqueous solvents solved
most of the drawbacks of the microsized powders Stable dispersions of calcium hydroxide
have been successfully applied (replacing polymers) as fixatives to re-adhere lifted paint
layers during many restoration workshops in Italy and in Europe as a consolidant The
FerronindashDini method (two steps the application of a saturated solution of ammonium
carbonate (NH4)2CO3 and the treatment with a barium hydroxide solution Ba(OH)2 also
called the barium method has long been the acknowledged method for the removal of
salts that threaten paintings reinforcing at the same time the porous structure However
commercially available carbonates and hydroxide powders have dimensions of several
micrometres much larger than the pores on the paint surface This means they donrsquot
penetrate the painting well and there is also a risk of damaging the artwork by a white
glaze forming on the surface (Berger 2006) Restoration should provide the reinforcement
of the porous structure and the consolidation of the surface layer of arte facts A few
simple principles can be considered to define the most appropriate restoration method
1) The treatment should be reversible so that one can revert to the original status of the
work of art at any desired time
2) All the applied chemicals must ensure the maximum durability and the chemical
inertness
3) The applied chemicals must invert the degradation processes without altering the
chemical composition of the artefacts and their physico-chemical and mechanical
properties (Baglioni 2006)
218 Commercial preservative used for preservation of mural paintings
Cleaning was done using soft brushes vacuum cleaner and Gumma paine (dough)
a natural latex sponge Areas near the window were very dirty with black soot and were
cleaned with micro fibrous cloths moistened with synperonic N (surfactant alkyl phenol
ethoxylate based on nonyl phenol) and neutralized with clean water In several places the
paint layers had separated from the substrate (exfoli-ation) In that cases loose paint flakes
were stuck back using Paraloid B72 (10 solution in ethanol) as sparingly as possible
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
37 Review of Literature
Paraloid was injected with syringe behind the exfoliated area twice pushed and held back
with Melinex (polyester film) until fixed on the third application (Bionda et al 2002)
In a period of significant growth of molds and intensive efforts to stop the mold
contamination some of the lines of certain paintings were obscured or faded Solutions of
ethanol formalin 91 and Thiabendazole (TBZ) were used but they were not very
effective Para-formaldehyde fumigation was adopted beginning in 1981 to establish an
emergency treatment sensitivity of microorganisms from studied samples was tested
against Desogen by adding 1-3 (v v) in serial dilutions The best concentration
3 (vv) was applied with a brush to prevent spreading of the spores In order to overcome
the problem of fungal attack suitable fungicides carbendizeme or kiroxy-I or 5 solute of
N formaldehyde can be used Shellac solution in spirit or 2 solution of polyvinaycletate
in toluene can be used as preservative and consolidantsTo control insect and fungal attack
fumigants like pyrethrum DDT or 5 solution of sodium penta chlorophenate in kerosene
oil 2 to 5 solution of PVA in toluene or 2 to 5 solution of paraloid B-72 in toluene or
acetone be used (Miura 2009) Microclimatic conditions constitute a critical factor in the
conservation of cave paintings The unstable microclimatic condition is one of the factors
that always affect the state of conservation of mural paintings In the environmental-
monument system knowledge of the functional environment and climatic conditions of the
surroundings are necessary for the identification of causes of decay (Singh 2011)
Furthermore the risk of formation of indoor bioaerosols in residential and public
buildings (offices schools museums etc) has attracted interest in the last years due to
socio-economic as well as sanitary reasons (Ripka 2005) Thus it is important in aspects of
health and maintenance of Cultural Heritage to analyse the complete microflora to further
develop biocides for harmful microorganisms and methods for restoration of damaged
objects of art The biocidal testing was carried out on one representative algal species of
the two classes of algae viz Chlorococcum sp (green) and Chroococcus sp (blue-green)
found to be common in all the samples Efficiency tests were carried out both in liquid as
well as solid media containing algal suspensions by adding a biocide solution of known
concentration and determining the growth of the microorganism after the incubation
period The biocides used for the past studies were
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
35 Review of Literature
with cultural diversity have expanded these principles Taking into account these and
additional relevant contributions such as the ICOM-CC Code of Ethics (1984) Document
of Pavia (1997) and ECCO Professional Guidelines (1997) the aim of this document is
to provide more specific principles for the protection preservation and the conservation
restoration of wall paintings This document therefore reflects basic and universally
applicable principles and practices and does not take into account particular problems of
regions or countries which can be supplemented at regional and national level by
providing further recommendations where necessary
217 Preservation techniques of the mural paintings
The removal of fat salts varnishes and pollutants from the surfaces of the works
of art are mostly done by chemical and mechanical methods At the end of the 19th
century the practices of restoration methods that do not inhibit further future interventions
was considered acceptable During the 1960s several chemicals such as polymeric resins
were synthesized and applied as a consolidation or protection agents The accepted idea
was that these substances could be removed at any time leaving a completely unaltered
substrate On the basis of origin archaeological objects can be classified as follows
(Carretti 2005)
1 Inorganic It includes siliceous and nonsiliceous materials Archaeological materials
produced from stones terracotta ceramics and glass can be included under siliceous
materials whereas objects made of metals can be included under nonsiliceous inorganic
materials Again metal objects can be classified as ferrous metals and non-ferrous metals
Objects made of iron are termed as ferrous metal objects whereas metal objects made from
other than iron is termed as non-ferrous metal objects
2 Organic It includes archival and anthropological materials Again archival materials
include paper bhojapatra tadapatra textiles wooden objects miniature paintings whereas
anthropological objects include bone and ivory leather feather and fur etc
In the past restoration of paintings and other old artwork often involved application
of acrylic resins to consolidate and protect them One of the most important tasks for
modern restorers is thus to remove these layers because it turns out that acrylic resins not
only by drastically changing the optics of the treated artwork but in many cases they
accelerate their degradation The scientists use an oil-in-water microemulsion with the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
36 Review of Literature
organic solvent para-xylene as the oil component The matrix makes the cleaning agent
viscous so that it cannot enter very far into the pores of a painting (Carretti 2005)
Nanoparticle treatment is the logical evolution of the Ferroni-Dini method
Dispersions of kinetically stable Ca (OH)2 nanoparticles in non-aqueous solvents solved
most of the drawbacks of the microsized powders Stable dispersions of calcium hydroxide
have been successfully applied (replacing polymers) as fixatives to re-adhere lifted paint
layers during many restoration workshops in Italy and in Europe as a consolidant The
FerronindashDini method (two steps the application of a saturated solution of ammonium
carbonate (NH4)2CO3 and the treatment with a barium hydroxide solution Ba(OH)2 also
called the barium method has long been the acknowledged method for the removal of
salts that threaten paintings reinforcing at the same time the porous structure However
commercially available carbonates and hydroxide powders have dimensions of several
micrometres much larger than the pores on the paint surface This means they donrsquot
penetrate the painting well and there is also a risk of damaging the artwork by a white
glaze forming on the surface (Berger 2006) Restoration should provide the reinforcement
of the porous structure and the consolidation of the surface layer of arte facts A few
simple principles can be considered to define the most appropriate restoration method
1) The treatment should be reversible so that one can revert to the original status of the
work of art at any desired time
2) All the applied chemicals must ensure the maximum durability and the chemical
inertness
3) The applied chemicals must invert the degradation processes without altering the
chemical composition of the artefacts and their physico-chemical and mechanical
properties (Baglioni 2006)
218 Commercial preservative used for preservation of mural paintings
Cleaning was done using soft brushes vacuum cleaner and Gumma paine (dough)
a natural latex sponge Areas near the window were very dirty with black soot and were
cleaned with micro fibrous cloths moistened with synperonic N (surfactant alkyl phenol
ethoxylate based on nonyl phenol) and neutralized with clean water In several places the
paint layers had separated from the substrate (exfoli-ation) In that cases loose paint flakes
were stuck back using Paraloid B72 (10 solution in ethanol) as sparingly as possible
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
37 Review of Literature
Paraloid was injected with syringe behind the exfoliated area twice pushed and held back
with Melinex (polyester film) until fixed on the third application (Bionda et al 2002)
In a period of significant growth of molds and intensive efforts to stop the mold
contamination some of the lines of certain paintings were obscured or faded Solutions of
ethanol formalin 91 and Thiabendazole (TBZ) were used but they were not very
effective Para-formaldehyde fumigation was adopted beginning in 1981 to establish an
emergency treatment sensitivity of microorganisms from studied samples was tested
against Desogen by adding 1-3 (v v) in serial dilutions The best concentration
3 (vv) was applied with a brush to prevent spreading of the spores In order to overcome
the problem of fungal attack suitable fungicides carbendizeme or kiroxy-I or 5 solute of
N formaldehyde can be used Shellac solution in spirit or 2 solution of polyvinaycletate
in toluene can be used as preservative and consolidantsTo control insect and fungal attack
fumigants like pyrethrum DDT or 5 solution of sodium penta chlorophenate in kerosene
oil 2 to 5 solution of PVA in toluene or 2 to 5 solution of paraloid B-72 in toluene or
acetone be used (Miura 2009) Microclimatic conditions constitute a critical factor in the
conservation of cave paintings The unstable microclimatic condition is one of the factors
that always affect the state of conservation of mural paintings In the environmental-
monument system knowledge of the functional environment and climatic conditions of the
surroundings are necessary for the identification of causes of decay (Singh 2011)
Furthermore the risk of formation of indoor bioaerosols in residential and public
buildings (offices schools museums etc) has attracted interest in the last years due to
socio-economic as well as sanitary reasons (Ripka 2005) Thus it is important in aspects of
health and maintenance of Cultural Heritage to analyse the complete microflora to further
develop biocides for harmful microorganisms and methods for restoration of damaged
objects of art The biocidal testing was carried out on one representative algal species of
the two classes of algae viz Chlorococcum sp (green) and Chroococcus sp (blue-green)
found to be common in all the samples Efficiency tests were carried out both in liquid as
well as solid media containing algal suspensions by adding a biocide solution of known
concentration and determining the growth of the microorganism after the incubation
period The biocides used for the past studies were
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
36 Review of Literature
organic solvent para-xylene as the oil component The matrix makes the cleaning agent
viscous so that it cannot enter very far into the pores of a painting (Carretti 2005)
Nanoparticle treatment is the logical evolution of the Ferroni-Dini method
Dispersions of kinetically stable Ca (OH)2 nanoparticles in non-aqueous solvents solved
most of the drawbacks of the microsized powders Stable dispersions of calcium hydroxide
have been successfully applied (replacing polymers) as fixatives to re-adhere lifted paint
layers during many restoration workshops in Italy and in Europe as a consolidant The
FerronindashDini method (two steps the application of a saturated solution of ammonium
carbonate (NH4)2CO3 and the treatment with a barium hydroxide solution Ba(OH)2 also
called the barium method has long been the acknowledged method for the removal of
salts that threaten paintings reinforcing at the same time the porous structure However
commercially available carbonates and hydroxide powders have dimensions of several
micrometres much larger than the pores on the paint surface This means they donrsquot
penetrate the painting well and there is also a risk of damaging the artwork by a white
glaze forming on the surface (Berger 2006) Restoration should provide the reinforcement
of the porous structure and the consolidation of the surface layer of arte facts A few
simple principles can be considered to define the most appropriate restoration method
1) The treatment should be reversible so that one can revert to the original status of the
work of art at any desired time
2) All the applied chemicals must ensure the maximum durability and the chemical
inertness
3) The applied chemicals must invert the degradation processes without altering the
chemical composition of the artefacts and their physico-chemical and mechanical
properties (Baglioni 2006)
218 Commercial preservative used for preservation of mural paintings
Cleaning was done using soft brushes vacuum cleaner and Gumma paine (dough)
a natural latex sponge Areas near the window were very dirty with black soot and were
cleaned with micro fibrous cloths moistened with synperonic N (surfactant alkyl phenol
ethoxylate based on nonyl phenol) and neutralized with clean water In several places the
paint layers had separated from the substrate (exfoli-ation) In that cases loose paint flakes
were stuck back using Paraloid B72 (10 solution in ethanol) as sparingly as possible
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
37 Review of Literature
Paraloid was injected with syringe behind the exfoliated area twice pushed and held back
with Melinex (polyester film) until fixed on the third application (Bionda et al 2002)
In a period of significant growth of molds and intensive efforts to stop the mold
contamination some of the lines of certain paintings were obscured or faded Solutions of
ethanol formalin 91 and Thiabendazole (TBZ) were used but they were not very
effective Para-formaldehyde fumigation was adopted beginning in 1981 to establish an
emergency treatment sensitivity of microorganisms from studied samples was tested
against Desogen by adding 1-3 (v v) in serial dilutions The best concentration
3 (vv) was applied with a brush to prevent spreading of the spores In order to overcome
the problem of fungal attack suitable fungicides carbendizeme or kiroxy-I or 5 solute of
N formaldehyde can be used Shellac solution in spirit or 2 solution of polyvinaycletate
in toluene can be used as preservative and consolidantsTo control insect and fungal attack
fumigants like pyrethrum DDT or 5 solution of sodium penta chlorophenate in kerosene
oil 2 to 5 solution of PVA in toluene or 2 to 5 solution of paraloid B-72 in toluene or
acetone be used (Miura 2009) Microclimatic conditions constitute a critical factor in the
conservation of cave paintings The unstable microclimatic condition is one of the factors
that always affect the state of conservation of mural paintings In the environmental-
monument system knowledge of the functional environment and climatic conditions of the
surroundings are necessary for the identification of causes of decay (Singh 2011)
Furthermore the risk of formation of indoor bioaerosols in residential and public
buildings (offices schools museums etc) has attracted interest in the last years due to
socio-economic as well as sanitary reasons (Ripka 2005) Thus it is important in aspects of
health and maintenance of Cultural Heritage to analyse the complete microflora to further
develop biocides for harmful microorganisms and methods for restoration of damaged
objects of art The biocidal testing was carried out on one representative algal species of
the two classes of algae viz Chlorococcum sp (green) and Chroococcus sp (blue-green)
found to be common in all the samples Efficiency tests were carried out both in liquid as
well as solid media containing algal suspensions by adding a biocide solution of known
concentration and determining the growth of the microorganism after the incubation
period The biocides used for the past studies were
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
37 Review of Literature
Paraloid was injected with syringe behind the exfoliated area twice pushed and held back
with Melinex (polyester film) until fixed on the third application (Bionda et al 2002)
In a period of significant growth of molds and intensive efforts to stop the mold
contamination some of the lines of certain paintings were obscured or faded Solutions of
ethanol formalin 91 and Thiabendazole (TBZ) were used but they were not very
effective Para-formaldehyde fumigation was adopted beginning in 1981 to establish an
emergency treatment sensitivity of microorganisms from studied samples was tested
against Desogen by adding 1-3 (v v) in serial dilutions The best concentration
3 (vv) was applied with a brush to prevent spreading of the spores In order to overcome
the problem of fungal attack suitable fungicides carbendizeme or kiroxy-I or 5 solute of
N formaldehyde can be used Shellac solution in spirit or 2 solution of polyvinaycletate
in toluene can be used as preservative and consolidantsTo control insect and fungal attack
fumigants like pyrethrum DDT or 5 solution of sodium penta chlorophenate in kerosene
oil 2 to 5 solution of PVA in toluene or 2 to 5 solution of paraloid B-72 in toluene or
acetone be used (Miura 2009) Microclimatic conditions constitute a critical factor in the
conservation of cave paintings The unstable microclimatic condition is one of the factors
that always affect the state of conservation of mural paintings In the environmental-
monument system knowledge of the functional environment and climatic conditions of the
surroundings are necessary for the identification of causes of decay (Singh 2011)
Furthermore the risk of formation of indoor bioaerosols in residential and public
buildings (offices schools museums etc) has attracted interest in the last years due to
socio-economic as well as sanitary reasons (Ripka 2005) Thus it is important in aspects of
health and maintenance of Cultural Heritage to analyse the complete microflora to further
develop biocides for harmful microorganisms and methods for restoration of damaged
objects of art The biocidal testing was carried out on one representative algal species of
the two classes of algae viz Chlorococcum sp (green) and Chroococcus sp (blue-green)
found to be common in all the samples Efficiency tests were carried out both in liquid as
well as solid media containing algal suspensions by adding a biocide solution of known
concentration and determining the growth of the microorganism after the incubation
period The biocides used for the past studies were
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
38 Review of Literature
1) Benzalkonium chlorides (MS Loba-chime Indo-Australian Co Bombay)
2) 2-Chloro-4 ethyl amino-6-isopropylamino-s-triazine commercially known as
Atrazine (MS Rallis India Ltd Bombay)
3) chloro-4 6-bis (ethylamino)-s-triazine commercially known as Simazine (MS
Bharat Pulverising Mills Ltd Bombay)
4) [3-(34-dichlorophenyl)-11-dimethyl urea] commercially known as Diuron (MS
Bharat Pulverising Mills Ltd Bombay)
Traditional conservators confront a challenging set of issues that must be resolved
prior to the restoration of any community mural In some cases the special nature of
community murals creates conflicts with conservatorsrsquo normal practices so it is useful to
begin by considering briefly the differences between community murals and other forms of
painting To do that it is necessary to better understand the nature of community murals
The biofilm was removed where possible with a low concentration of hydrogen peroxide
solution then the area was treated with about 70 isopropyl alcohol The conservation
techniques in Italy are barium hydroxide starts a reaction which converts the calcium
carbonate (lime) into calcium hydroxide (slaked lime) which means a new carbonation
process will take place and create adhesion to the wall The ammonium and water
evaporates The crystals of barium sulfate act as filler in the pores of the mural and can
also be washed away (Garreau 2007)
Another choice for protecting the mural is to use some of the various graffiti-
resistant finishes that are commercially available These range from protective wax
coatings that are removed with hot water to the 2-component solvent-based polyurethane
coatings Breath ability is important to the successful adhesion of acrylic products If a
mural encompasses an entire wall made of a masonry product it is advisable to apply thin
coats of MSA Varnish This will allow interior condensation and evaporating solvents and
out gassings to escape A mixture of shellac and alcohol in ratio of 5050 is also used
Readhesion of the paint layer was done by application of acrylic resin emulsion (primal
AC 335)the emulsion was applied by brush along the border with water and alcohol
(Agrawal and Pathak 2001)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
39 Review of Literature
219 Conservation agents
Indian Association for Study of Conservation of Cultural Property IASC was
founded in the year 1966 as a spin off of the UNESCOs Regional Seminar at New Delhi
The Association provided a National forum for the conservators practicing in isolation to
come together and share their experience among the peers and also to seek answers to
their problems and keep the professionals informed of the difficulties in carrying out their
work The forum took the responsibility of information dissemination about the new
developments in the area of conservation Formation of such a specialized professional
Association gave a big boost to the conservation research activity in the country
(Singh 1998)
The Archaeological Survey of India (ASI) under the Ministry of Culture is the
premier organization for the archaeological researches and protection of the cultural
heritage of India Maintenance of ancient monuments and archaeological sites and remains
of national importance is the prime concern of the ASI For the maintenance of ancient
monuments and archaeological sites and remains of national importance the entire country
is divided into 24 Circles The Archaeological Survey of Indiarsquos Science Branch is
responsible mainly for the chemical conservation treatment and preservation of some three
thousand five hundred ninety three protected monuments besides chemical preservation of
museum and excavated objects countrywide
Nanotechnology has recently found practical applications in the Conservation and
Restoration of the Worldrsquos Cultural Heritage (CAR-WHC) Baglionis group was among
the first to synthesize nanoparticles in non-aqueous solvents with the optimal properties for
application to cultural heritage conservation Nanoparticles of calcium and magnesium
hydroxide and carbonate have been used to restore and protect wall paints such as Maya
paintings in Mexico or 15th century Italian masterpieces (Berger 2006)
A few years back the INTACH Indian Council of Conservation Institutes (ICCI)
conducted a survey of wall paintings in various state of India and found that a large
number of wall paintings exist in temples palaces havelies churches forts and so on The
number of wall paintings in each state is very large but the researchers could locate and
examine only a few of them From some wall-paintings they collected samples of plasters
and paints and analyzed them They could get funding for conservation of some of them
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
40 Review of Literature
and they were conserved by their teams (Agrawal 2007) A state-wise break-up of their
survey work is as given below table
Table-22 Status of Indian mural paintings (Agrawal 2007)
SNo Name of the State No of murals sites
surveyed
Status of sites
conserved
1 Bihar 8 Nil
2 Himachal Pradesh 4 2
3 Jammu amp Kashmir 17 Nil
4 Tamil Nadu 3 2
5 Madhya Pradesh 36 8
6 Maharashtra 1 1
7 Kerala 61 3
8 Rajasthan 72 18
9 Haryana 1 1
10 Punjab 2 Nil
11 Karnataka 18 4
12 Sikkim 1 Nil
13 Uttar Pradesh 41 4
14 Uttarakhand 11 1
15 Orissa 79 5
220 Recent scenario of preservation
The scanning lidar fluorosensor experimental apparatus was designed by keeping in
mind that very often artworks and especially frescos on tombs are placed in small
chambers with a narrow entrance where only a limited space is available In order to
facilitate field operations the optical and mechanical supports have been assembled on a
small size optical bench contained in a box for easy transportation The compact LIF
system is designed to be coupled with another laser scanning device used for
characterization of surfaces the amplitude modulated LFR developed in the same
laboratory for 3D model reconstruction of object and environments (eg whole chambers)
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
41 Review of Literature
The mechanical mountings are then conceived to offer a rapid and stable hookup to the
LRF apparatus in the case of simultaneous operation (Giovagnoli 2008)
221 Data recording
In order to facilitate the input and retrieval of data from the text fields a guide for
the compilation of the data record card was drawn up For each entry the guide explains the
type of data considered essential the technical vocabulary to adopt and cites a series of
illustrative examples showing the type of syntax and punctuation required The program
used was File Maker Pro 71 produced by the Claris Corporation The data record card is
divided up into six sections
1 Reference data This contains basic information relating to the work in question
(geographical location description of objectsite measurements author period
etc) The section ends with a paragraph on the methods of inspecting the painting
(visual tactile examinable support) which is of fundamental importance for
assessing the integrity and completeness of the survey (Giovagnoli 2008)
2 Documentation This section contains the necessary documentary references
relating to the work of a graphic photographic or written (bibliographical or
archival) nature
3 Positiondisplay characteristics The information contained in this section is brief
and acquired through simple visual examination as it will be presented in greater
detail on the environmental data record card
4 Technical data and conservation condition This is the most technical and analytical
section of the sheet in that it presents all the visually deducible data on the
constituent materials execution techniques and conservation condition of the
painting The section is divided into three parts presenting data that refers to the
individual layers or elements ideally comprising the work support structure
preparatory layers and paint layers The collection of data for each individual
section is carried out in the same order First the constituent materials and
execution techniques are examined and then the alterations linked to factors of
deterioration of a physico-chemical and biological nature and lastly the restoration
treatments carried out in the past An ldquoOtherrdquo entry is always included to provide
for those less common aspects not specified in the other fields As far as the
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala
A Study on Microbial Deterioration of Ancient South Indian Mural Paintings and
Fabrication of Biobased Natural Protective Coating for its Conservation --------------------------------------------------------------------------------------------------------------------------------------------------------------------
42 Review of Literature
indicated factors of alteration are concerned an assessment of the extent of the
damage is recorded and a calculation expressed in percentage of its distribution in
relation to the overall surface (Giovagnoli 2008)
5 Indication of treatment programmes Based on the previously recorded
documentary technical and conservation elements this section proposes the
treatment programmes that need to be carried out indicating the type and degree of
urgency Five different time related categories were specified for this purpose
bull Emergency treatment
bull Short-term treatment
bull Medium-term treatment
bull Long-term treatment
bull Maintenance and inspection
222 Conclusion
From the above supporting articles the present study was designed in such a way to
develop a natural preservative gel for the conservation of the mural painting The present
study focuses on development of bio-based natural preservative coating for mural painting
and monuments The microbial flora of air from selected archeological sites was studied
The dye pigment from the plant sources and mineral sources used in traditional mural
painting were extracted and their antimicrobial property was studied The physico ndash
chemical characteristics of the extracted dyes were studied using SEM-EDAX FTIR and
GC-MS analysis Various combinations of these dyes and their antibacterial property were
studied Field trials for assessing the antimicrobial durability of developed natural
preservative were studied by coating it on mural paintings at Institute of Mural Paintings
Guruvayoor Kerala