Introduction

ntroduction

Chapter-

ntroduction

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INTRODUCTION

Chapter-1 “They are without leaves, without buds and without

flowers yet they form fruit”

1.1 Mushroom: A fungus

This intellectual definition delinrates macrofungi through the vison of S. T. Chang

(1993), an eminent mycologist, tha captures the essence of its versatility and

beauty. Technically speaking “macrofungi” that are mostly scattered throughout

Ascomycota, Basidiomycota and Zygomycota are defined as those fungi which

bear large, easily observed spore-bearing structures that are formed above or

below ground (Mueller et al., 2007). A recent global study regarding macrofungal

diversity estimated it to be within the range of 53,000 to 110,000 species (Mueller

et al., 2007).

Under the term ‘‘useful mushroom’’ (Lelley, 2005) all the mushrooms which

are used by man for some economical importance are considered. This would

contain all the edible mushrooms, toxic or cryptic mushrooms with medicinal

properties, mushrooms that can be used in forestry, industry, biotechnology,

bioremediation, restoration, reforestation, etc. Wild mushrooms are believed to be

one of the most important non-wood forest products. Almost 3000 species or

more have gastronomical uses and 100 or more have promising clinical activity

against cancer and other chronic diseases. Because of which UN-FAO promotes

sustainable use of macrofungi and use them for forests management and

conserve their biodiversity as well that would have a long term effect on income-

generation and food security (FAO, 1991).

1.1.1 An overview on fungi

Fungi is one of the most prominent and biodiverse organism to inhabit and

influence this planet. They are neither animal nor plant though some people

consider them plants for various reasons, but they differ from plants in that they

lack the green chlorophyll that plants use to manufacture their own food and

energy. For this reason they are placed in a different Kingdom of their own. The

true fungi belong to the kingdom Eukaryota that encompasses 4 phyla, 103

orders, 484 families and 4979 genera (Manoharachary et al., 2005).

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INTRODUCTION

Chapter-1 Fungi play critical role in ecosystem be it grassland and forest ecosystems

they are equally vital as they are an indispensible link in the food web as

decomposers and pathogens that have many different kinds of associations with

other organisms, both living and dead. In other words being heterotrophs it is

involved in decomposition, nutrient cycling, and nutrient transport and are

indispensable for achieving sustainable development (Palm and Chapela, 1998).

They serve the plant kingdom by mutualistic ties to which over 90% of plants

subscribe in form of mycorrhizal associations enabling them to scavenge essential

minerals from nutrient poor soils. They are also known for their positive and

negative economic impacts on human beings. On the positive axis they are

employed for brewing, baking, industrial fermentation, pharmaceutical and

biotechnical exploitation and direct cultivation as food. Industrial use of fungi has

now developed in leaps and bounds. Apart from edible mushroom cultivation of

several species other direct or indirect commercial engagements are being

pursued. Fungi have become integral to immunosupressive drugs, steroids,

hormones, organic acids, and fermented foods as soy, cheese, fabric finishing,

pollution treatment and several other such processes. On negative axis they

cause diseases in humans, animals and plants and degrade artifacts and utility

materials. Mycotoxins from micro- and macrofungi cause harm and even fatality to

animal and human lives each year. They have the most awesome methods and

strategies of dissemination as Entomopbtbora muscae, that infects houseflies and

reaches its brain to cause it to crawl high where it can sproulate and spread

further (Carlilie et al., 2001).

1.1.2 Biodiversity of fungi

Fungi is the 2nd most diverse of all groups and is considered as a prime

member of the other “mega-diverse” groups like insects, bacteria, arachnids and

nematodes (Gaston, 2000; Hawksworth and Kalin-Arroyo, 1995). Hawksworth

estimated the total number of fungal species by calculating that there is an

average of six known fungal species for every known plant species in Finland,

Switzerland, the UK and the USA. Based on an estimated 250,000 plant species

worldwide, Hawksworth calculated that there are approximately 1.5 million extant

fungal species, of which 95% are not described (Hawksworth and Rossman,

1997). However, the high species richness predicted by the ‘‘ratio estimate’’ has

been cast into doubt. But some studies based on meta-analysis of macrofungal

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INTRODUCTION

Chapter-1 diversity have shown that tree diversity is a promising surrogate for macrofungal

diversity at large spatial scales (Schmit et al., 2005). An interesting study

highlighted that the rate at which 74,000–120,000 species of total 1.5 million

fungal species were discovered it would theoretically take 1290 years without

considering the rate of extinction (Hawksworth, 2001).

The comparison of diversity of fungal species on global and Indian levels is

compared below (Table 1.1). The Ascomycotina and Deuteromycotina are the

least estimated at national level, which doesn’t necessarily indicate that they are

rare but the current scenario may be due to the paucity of data. According to

Manoharachary et al. (2005), 205 new genera have been described from India. Of

these, approximately 27,000 species are reported to colonize diversified habitats

implying that there has been a 10 fold increase in registering the species during

past 70 years.

Table 1.1. An estimate of Fungal diversity in India (Manoharachary et al., 2005)

PHYLA GLOBAL INDIA Percentage

Myxomycotina 450 380 84.44

Mastigomycotina 308 205 66.55

Zygomycotina 55 50 90.91

Ascomycotina 2000 745 37.25

Basidiomycotina 357 232 64.98

Deuteromycotina 4100 468 11.41

Total 7270 2080 28.61

1.1.3 The taxonomic shelters of macrofungi

The kingdom fungi include a wide variety of whopping diversity in terms of

micro- or macroscopic morphology, ecological niches occupied, metabolism and

reproduction. An estimate revealed that 80% of the species in species-rich groups

of fungi are distributed widely and only 20% are distributed in limited niches. More

than 90% of fungi are yet to be evaluated for antibiotics in light of the current

challenge of microbial resistance. The Eumycota or true fungi are broadly divide

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INTRODUCTION

Chapter-1 under the classes Chytridiomycetes, Zygomyces, Ascomycetes, Basidiomycetes,

and Mitosporic fungi.

Ascomycetes and Basidiomycetes, which contain most of the macrofungal

species, in addition to producing spores by a sexual process, form other types of

spores asexually and are known as ‘Higher fungi’. Different kinds of large fungi or

macrofungi have been recognized for thousands of years. In current English

edible ones are often called mushrooms and poisonous ones toadstools, which

are not taxomonical terms. During the eighteenth century, botanists made

considerable progress in the recognition and classification of the fungi, and early

microscopists observed and described hyphae and spores. The role of the edible

fruit bodies (or fruiting bodies) is the production of large numbers of spores by

means of which dispersal occurs. The spores are borne on the gills below the cap,

and a stalk raises the fruit body above the ground to facilitate spore dispersal by

air currents. Examination of the stalk, cap and gills with a microscope shows that

the fruit body is composed of long, cylindrical branching threads known as

hyphae. The hyphae are divided by cross-walls into compartments, which typically

contain several nuclei. Such compartments, together with their walls, are

equivalent to the cells of other organisms. The spores are borne on specialized

cells termed basidia in the Basidiomycetes or in sac like structures called ascus in

Ascomycetes (Carlilie et al., 2001).

The Ascomycota is the largest phylum of the Kingdom Fungi, with

approximately 32,000 species (Hawksworth et al., 1995). Three major groups or

classes of Ascomycota, including Euascomycetes (mostly filamentous,

sporocarpproducing as well as mitosporic or conidial forms), Saccharomycetes

(the true yeasts), and Archiascomycetes (a paraphyletic assemblage of basal

taxa) generally are recognized (Nishida and Sugiyama 1994; Taylor et al., 1994).

The Euascomycetes is the largest class of Ascomycota and includes the major

lineages of filamentous, sporocarpproducing taxa and their equally diverse

asexual relatives (anamorphs). It is arguably the most successful group of fungi,

including parasites, pathogens, and mutualists of plants, algae, and animals, as

well as saprobes able to decompose virtually all known organic substrata.

Pezizales is a basal lineage of the class (Berbee and Taylor 1993; Gargas et al.

1995; Platt 2000). It also may be the best-known and largest group of apothecial

fungi and includes numerous macroscopic forest species (e.g., Morchella species,

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INTRODUCTION

Chapter-1 Gyromitra species, Helvella species). The Pezizales is characterized by

operculate asci. The monophyly of the order is not strongly supported, however,

and numerous familial revisions have been proposed (O’Donnell et al., 1996).

Moreover, the group includes numerous, independent lineages of truffles

(O’Donnell et al. 1996) and, as an order, probably contains the majority of

ectomycorrhizal species of ascomycetes. Pyrenomycetes is a class name

formerly used to refer to a group of species with a particular shared morphology. It

now is used to designate a clade that includes the orders Diaporthales,

Halosphaeriales, Hypocreales, Lulworthiales, Microascales, Ophiostomatales,

Phyllachorales, Sordariales, and Xylariales (Hausner et al. 1992; Spatafora and

Blackwell 1993; Kohlmeyer et al. 2000). Although the taxa in the clade

encompass a wide range of macromorphologies and micromorphologies, the vast

majority have a flask-shaped ascomata or perithecia.

The Basidiomycota is the second largest phylum of Kingdom Fungi, with

approximately 23,000 species (Hawksworth et al. 1995), including many of the

common macroscopic forest fungi (e.g., mushrooms, shelf fungi). Classifications

of the Basidiomycota, with fungi possessing septate basidia assigned to the

Phragmobasidiomycetes (Heterobasidiomycetes) and fungi with nonseptate

basidia classified in the Homobasidiomycetes (Holobasidiomycetes) (Donk, 1966).

Basidiomycota generally is considered to include the classes Urediniomycetes

(rusts and relatives), Ustilagniomycetes (smuts), and Hymenomycetes

(mushrooms and relatives) (Wells, 1994). The Hymenomycetes consists of the

fleshy forest fungi (e.g., mushrooms, jelly fungi, shelf fungi) with which biologists,

naturalists, and nonmycologists are most familiar. The clade is united by a unique

mycelial structure, the dolipore septum, in which the cell walls near the pore of the

septum flare, and a membrane structure, the parenthesome, occurs on either side

of the pore (Moore, 1985). The parenthesome may be perforated or not,

depending on the clade, with the imperforated form being ancestral for the class.

homobasidiomycetous taxa with nonseptate basidia that lack a yeast phase in

their life cycles. This clade includes the mushrooms, shelf fungi, and stinkhorns,

all of which may produce mycorrhizae, decay litter and wood, or act as plant

pathogens and insect symbionts. Traditional classifications of the

homobasidiomycetous fungi were based largely on basidiocarp morphology with

particular emphasis on the sporeproducing region or hymenophore. For example,

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INTRODUCTION

Chapter-1 all of the mushrooms and their gilled relatives were grouped in the Agaricales, and

all of the poroid forms and their relatives were grouped in the Aphyllophorales.

The consensus arising from those studies is that overall, basidiocarp morphology

it is not a phylogenetically informative trait at higher taxonomic levels because of

repeated episodes of convergent and divergent evolution. The Hymenomycetes

includes an estimated eight major clades each of which encompasses multiple

basidiocarp and hymenophore morphologies like Polyporoid, Euagaric, Bolete,

Thelephoroid, Russuloid, Hymenochaetoid, Cantharelloid and Gomphoid-phalloid

(Hibbett and Thorn 2001). Morphologically the mushrooms can be broadly divided

in the following forms, as bracket shaped, stiped and poroid, gilled, smooth and

resupniate on woods, coralloid, hood like, dentoid or with cup shaped cap having

or lacking stipe etc. (Pacioni and Lincoff, 1981) some of the examples are given

below (Fig 1.1).

Figure 1.1. Various morphological forms of macrofungi.

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INTRODUCTION

Chapter-1 1.2 Bioprospecting

1.2.1 Bioprospecting: Defining it

Bioprospecting is defined as “the purposeful evaluation of wild biological material

in search of valuable new products” (Artuso, 2002). Biodiversity prospecting is the

exploration of wild plants and animals for commercially valuable genetic and

biochemical resources.

Ants of the tribe Attini and other termites known to rear and consume

mushrooms for over 50 million years are the natural frontiers of bioprospecting

(Muller, 1998). Ever since mankind has started living in community be it small or

large, the bioprospecting of nature for battling diseases has been a never ending

story. The trial and error efforts directed towards the betterment of the quality of

life was compiled orally or textually in due course of time, so that it can be

communicated vertically down the generations. Today contemporary natural

medicines in use have that are pure and well-defined chemotherapeutic chemical

entities. The evolution from herbal remedies to novel chemical entities in clinical

use today was a slow and gradual process that started with inquiring minds at the

beginning of the 19th century (Wetzel et al., 2010).

Friedrich Wilhelm Adam Serturner, a German pharmacist, reported the

isolation of a white crystalline powder from opium (Papaver somniferum), which

he named morphine in earlier 18th century. This was the 1st isolation of a pure

natural product that was commercialized two decades later by Heinrich Emanuel

Merck. The same molecule and several classes of analogues are being used as

analgesics even after 200 years. Later this led to isolation of several natural

products as strychnine, colchicine and codeine (Sneader, 2005).

The fact that 214,000 chemical entities are known to us indicates that

mankind has traversed a long way in drug discovery and bioprospecting in a

major way (DNP, 2010). The 20th century witnessed the discovery of the

antibacterial properties of penicillin, derived from the mould Penicillium notatum,

which was soon followed by various other antibacterials that gave physicians an

enormously powerful weapon in their battle against infectious diseases (Ji et al.,

2009).

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INTRODUCTION

Chapter-1 The products intended as outcome of bioprospecting programs range from

pharmaceuticals, agrochemicals, cosmetics, flavorings, fragrances to even

industrial enzymes. Post Convention of Biodiversity Intervention the

bioprospectors have become accountable to the countries from which biological

material had been collected. Thereafter the equitable benefit sharing and

technology transfer is required in exchange for access to biochemical resources

that include include genetic material as well as other chemical compounds that

can be derived from biodiversity.

Analysis of effective economic models estimating the value of biological

samples for pharmaceutical research revealed that demand curve for biological

samples is downward sloping because the market price for randomly collected

biological samples is likely to be little more than the cost of collecting them

(Simpson et al., 1996). The optimal bioprospecting strategy is expected to trigger

knowledge generating investments. Bioprospecting activities are intended to

support sustainable development in terms of widespread, long-term improvement

in economic opportunity and environmental well being, that bags incentives for

conservation. Moreover, apart from drug discovery resource sharing, the

validation of effective traditional practices can give rise to opportunities for

developing commercial-scale operations for production and extraction of

biochemical materials like raw materials, extracts, fractions, drug powders,

infusions or any of these in convenient pharmaceutical forms. The bulk supply of

raw materials and purified natural products can provide a source of revenue and a

means of developing technical and management capabilities. But, the laws of

supply and demand still hold; unless the commodity can be differentiated on the

basis of quality or other characteristics, prices and profits will be limited by the

ability of other suppliers to enter the market. These can offer for immediate

sustainable development and opportunities can grow with expanding market.

Apart from India several countries like Argentina, Australia, Bermuda,

Cameroon, Chile, China, Costa Rica, India, Indonesia, Jamaica, Malaysia,

Mexico, Nigeria, South Africa, and Suriname have actively taken part in

bioprospecting programs. Costa Rica and South Africa are two countries that are

using the experience and technical capabilities gained from initial bioprospecting

endeavors to develop more comprehensive value-added bioprospecting

programs. Since 1990 South Africa’s is actively progressing to develop the

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INTRODUCTION

Chapter-1 chemical and genetic value of its biodiversity. After completion of pilot projects

with several industrial participants the Chemtek division of South Africa’s

Commission on Scientific and Industrial Research launched its own pilot

bioprospecting effort. As a result of this effort an antiobesity agent named P57

was discovered from an indigenous South African plant. They were able to obtain

its intellectual property rights even though P57 is a mixture of phytochemicals.

This in turn led to the formation of a bioprospecting consortium involving

Commission on Scientific and Industrial Research, the South African Medical

Research Council, the Agricultural Research Council, the National Botanical

Institute, and several universities that road-mapped to evaluate the

pharmaceutical potential of all 23,000 species of vascular plants native to South

Africa. Meanwhile pushing forward the P57 project they have collaborated with

UK-based Phytopharm for technical assistance regarding manufacturing FDA

guidelines and Pfizer for funding to develop a manufacturing facility to produce

sufficient quantities of P57 for clinical trials. On the successful completion of the

project the parent body will receive a part of revenue (Horak, 1998).

Bioprospecting for genetic material that codes for medicinally or

agronomically valuable traits is targeted for the production of transgenic crop

varieties. The newly developed ‘‘golden’’ rice variety that many hope will help

reduce vitamin A deficiency in developing countries was developed using genes

from daffodils and two species of bacteria. The Diversa Corporation, a rapidly

growing biotechnology company that has entered into bioprospecting agreements

not only in Costa Rica and South Africa but also in Indonesia, Iceland, and

Bermuda, uses microbial DNA extracted from soil samples to genetically engineer

common microorganisms to produce novel chemical compounds. Biotechnological

techniques are also used as a means of producing commercial quantities of

complex natural products that were discovered through bioprospecting activities,

but have proven too difficult or costly to synthesize chemically. Examples include

the anti-cancer drug taxol, which was originally derived from the bark of the

Pacific Yew tree but is now produced using tissue culture techniques, and the

anti-coagulant hirudan, which is a chemical isolated from the saliva of the

common leech, Hirudo medicinalis, but is now produced in commercial quantities

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INTRODUCTION

Chapter-1 from transgenic strains of bacteria as well as from transgenic plants (Walsh,

2000).

Similarly the collaboration between Merck and Costa Rica’s National

Institute of Biodiversity has been fruitful in isolating novel compounds such as

arundifungin (Cabello et al., 2001) and durhamycin A (Jayasuriya et al., 2002).

1.2.2 Bioprospecting of traditional databases

The ethnobotanical-driven discovery of novel pharmacological agents highlights

the potential for using collected indigenous knowledge as a research tool.

Prostratin, an HIV therapeutic that activates the latently infected T-cell pool (Korin

et al., 2002), is a recent example of a potentially beneficial and lucrative

compound identified through ethnobotanical work in Samoa. Common to all drug

discovery programs high-throughput screening employed to identify potential

therapeutic leads by the application of a ‘brute-force’ method to examine

specimens for activity are lately found to be inefficient. This is because the

compounds that were active in vitro were inactive in vivo, as witnessed by a large,

random library screen for antiretrovirals that failed to identify any compounds that

possessed in vivo activity (Chapman et al., 2002). On the other hand there are

several mentions of medico-ethnobotanical records made by historians,

physicians, expatriates and indigenous people. Most of the herbal texts have been

preserved as historical artifacts, but lately, its potential in unraveling prized

ethnomedicinal practices have been realized. Gerard’s The Herball (Cox, 1998)

and plants in Herbarium Amboinense (Rumphius, 1741-1755) have firm-footed

these endeavors as several potent pharmaceutical constituents have been

unleashed on this line. Texts detailing natural pharmaceuticals have been found

that date back to the ancient Egyptians and Sumerians (c. 3100 BC). Records in

hieroglyphs (Egypt) and cuneiforms (ancient Mesopotamia) are frequently recipes,

usually listing the ailment and providing ingredients and preparation and

administration instructions (Estes, 1989; Manniche 1989). Hundreds of unstudied

Latin, Greek and Arabic herbal texts and recipe books from the Middle Ages

remain in manuscript depositories across Europe, northern Africa and the Middle

East.

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INTRODUCTION

Chapter-1 In several remote places that lack medical facilities, the community

traditional practices are prevalent. They use biological cures for disease that

aren’t laboratory produced or patented. Envisioning the immense potential

harnessed by these traditional practices a surge of interest in drug discovery

based on ethnomedicinal foundation has long taken off. Though this search is

often called bioprospecting, but it may also be termed biopiracy by those who

disapprove of the occasionally exploitive methods used by large companies

desirous of being the first ones to patent a newly discovered biological “cure”. The

current work is registered with State Department of Forest, biodiversity division

and is being officially permitted.

A growing demand for herbal medicines in North America and Europe as

well as rise in epidemics like malaria, tuberculosis and HIV/AIDS in Sub-Sahara

African have created an expanding market for indigenous herbal medicines

(Reihling, 2008). Traditional healers, plant gatherers, petty traders, research

institutions and private corporations have assembled around the issues of

standardization and commercialization of local knowledge about plants.

Bioprospecting is engaged by highthroughput screening or through traditional

healers. Both of these strategies have been combined to maximize the outputs

(Berlin and Berlin, 2005).

1.2.3 Resources of and traditional practices in ethnomycology

Ethnomedicinal use of plants is probably 60,000 years or more old, when their use

by Neanderthals is evidenced by the pollen deposits at one of the graves of

Shanidar caves located in the Zagros Mountains of Kurdistan in Iraq (Solecki,

1975). Some texts from Mesopotamia, circa 2600 BC are believed to be the oldest

medical oeuvre compiled on hundreds of clay tablets in cuneiform and

encompasses medicinal details on 1,000 plants and plant-derived substances,

such as the oils of Cedrus species (cedar), the resin of Commiphora myrrha

(myrrh) and the juice of the poppy seed Papaver somniferum (Newman et al,

2000). Around 800 complex prescriptions and more than 700 natural agents such

as Aloe vera (aloe), Boswellia carteri (frankincense) and the oil of Ricinus

communis (castor) are found in the ancient Egyptian Ebers Papyrus that date

back to 1550 BC (Zhong and Wan, 1999). Descriptions on more than 400 natural

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INTRODUCTION

Chapter-1 agents in delineated the work called Corpus Hippocraticum by the Greek

physician Hippocrates of Cos around circa 460–377 BC (Castiglioni, 1985).

Medicinal use of some of these herbs is still found to be prevalent among several

communities.

The advent of Ethnomycology was witnessed long before the very term

being coined by R. Gordon Wasson (1967), who also unleashed the depiction of

“Soma” as a mushroom summed up in 120 slokas. An excerpt from, “Rigveda”,

explicitly matches the morphology of a mushroom. It is a collection of ancient

Indian sacred hymns dated back to the late Bronze Age, which would be

between 1700–1100 BC. Soma is an ancient drug that was used for long life and

consumed as worship by the priests of Rig Veda. It was appreciated for its life

extending other therapeutic and psychological effects. It is believed to be

introduced by the Aryan people, when they inhabited valleys of Northern India.

Soma was said to be the symbol of power of sacrifice and was a common

sacrificial offering. It was a drink made before the sacrifice and was consumed by

the priests. The 9th book of Rigveda is loaded with attributes and importance of

soma (Mulhollan, 1980). There has been a lot of debate on whether soma is

mushroom or not. Though the arguments are focused majorly on Amanita not

being the ideal soma and this has been the source of disagreement. This was

proposed by Wasson in connection to other Eurasian practice linked to its

psychoactive species. There are compelling evidences like verses sighterd below

which match to the morphology of an agaric mushroom. Thus it may be possible

that the soma can be another mushroom rather than any species of Amanita as it

is said to be confined to mountains.

V 43 4c madhvo rasam sugabhastir giristham

Meaning - Plant from mountain

V 85 2d divi suryam adadhat somam adrau

Meaning - he has placed soma on mountain top

IX 62 4A asavya amsur madayapsu dakso gristhayah

Meaning - soma stalk seated on mountain top

IX 66 5 pari dhamani yani te tvam somasi visvatah pavamana rtubhih kave

Meaning – Your shining rays spread a filter on the back of heaven, O Soma, with thy forms.

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INTRODUCTION

Chapter-1 This may also relate to macrofungi which may have luster like Ganoderma

lucidum. The juice was taken directly or with milk or curd. IX 69 5 pra kristiheva susa eti roruvad asuryam varnam ni rinite asya tam jahati vavrim pitur eti niskrtam upaprutam krnute nirnijam tana Meaning – Aggressive as a killer of people he advances, bellowing with power.

He sloughs off the saurian color that is his. He abandons his envelope, goes to the rendezvous with the father. With what floats he makes continually his vesture-of-grand-occasion.

This disposition is attributed to the universal veil found in agarics and is closest to

the description of the mushroom.

Since its identifying characters were not mentioned the Soma of Rigveda

was changed to another form that was clearly defined in later religio-medical texts.

This religion based science is thought to develop since 6000 BC (Lee, 1949). The

principles of Ayurveda that stemmed from Atharvaveda were organized into

treatises around 800 BC, by Charaka and Sushruta (Sneader, 2005). Bower

manuscript, which is the excavated oldest preserved written material dated to the

4th century AD, has mentions of the works of Sushruta (Kutumbian, 1999)

indicating that it was a very prevalent school of practice. The teachings of sage

Sushruta was earlier put together in form of a treatise known as “Sushruta

Samhita”. It has 184 chapters that encompass issues regarding 1,120 illnesses,

700 medicinal plants, 64 and 57 preparations from mineral and animal sources

respectively (Dwivedi and Dwivedi, 2007). In this awesome compilation Sushrut

classifies mushrooms according to its theraputic effect, ecology and gastronomic

outcomes. They were in general addressed as “Udbhida” and were presented as

follows.

� Palala: These grew on stacks of straw were claimed to be sweet in taste

and digestion, produced a state of dryness and subdued the 3 deranged

humours of the body.

� Venn: These grew on the stems of bamboo and were found to be

astringent in taste and aggravated the bodily Vayu.

� Ikshu: These grew on the sugar-cane were claimed to be sweet pungent in

taste leaving behind an astringent after taste were cooling in potency.

� Udbhida: These were hypogeal or said to appear from beneath the surface

of the ground. They were heavy to digest and didn’t generate the Vayu.

Their tastes varied according to the nature of the soil.

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INTRODUCTION

Chapter-1 � Karisha: These grew on the compost heap of decomposing cow-dung and

were claimed to aggravate Vayu or were know to be heat generating in

other words.

At the end of his discussion Sushrut stated that the shepherds knew better

about these in greater deal and can be counsulted for more onformation. Thus in

other words he suggested that the enthnomycological database amongst the

forest wanderers were rich as they took the cattle for grazing and did

bioprospecting of macrofungi for edible or medicinal use. This was taken into

account and thus apart from traditional practitioners, such people were also

involved in the study.

Documented medicinal use of mushrooms laps back to18th century in case

of wound healing by Fomes fomentarius in (Roussel, 2002), also recorded along

with Piptoporus betulinus from an 5300 years old “iceman” (Stamets, 2002).

Traditional medico-chronicles of Slavic countries enshrine around 40

medicinal species for numerous human diseases. Rural Russian people of

Kamchatka believed Amanita muscaria (fly agaric) as "the god of hard drinking

and a chief of poisonous potions," and those in Kostroma region used its tinctures

against stomachache or gastric disease and other diseases. The farmers used it

as soporific by taking five or six drops to fall asleep. In Belorussia its mycelia were

grown on cow dung from pileus and were used against rheumatic aches by

rubbing it on the sore area. In Siberia its tincture was taken as a beverage to aid

in the healing of broken bones after fractures. One of the first medicinal

mushrooms taken at the Fomitopsis officinalis (larch polypore) was taken as the

direct orders of the Russian Tzar and was later used as styptic and purgative or to

treat bronchial asthma, night sweats of tubercular patients. American-Indian

believed that F. officinalis had miraculous powers. In Ancient Rome Pliny the

Elder suggested its use for treatment of stomach, dyspepsia, liver (including

jaundice), kidney, and urinary bladder (especially when urination is difficult, such

as while passing bladder stones) diseases; against tuberculosis, asthma,

epilepsy, and also as antidote after snake, spider, or scorpion bites. Siberian

farmers used it as a styptic to cauterize a bleeding wound, and against

indigestion, hemorrhoids, uterus, breast, esophagus, and stomach cancers.

Similarly Fomitopsis pinicola (red-belted polypore) was very common in the

Eastern countries for its antitumor and sedative properties. Moreover, the

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INTRODUCTION

Chapter-1 American Pharmacopoeia of the 19th century recommended F. pinicola for stable

spasmodic fevers, chronic diarrhea, dysentery, jaundice, and diuresis. This

species was known in eastern Canada as "Mech quah" and was used as an

emetic for stomach cleansing (Denisova, 1998).

Inonotus obliquus (Clinker Polypore), known as chaga, was used for

treatment of different gastrointestinal diseases (ulcers, gastritis) and sometimes

against lip, skin, stomach, and rectal cancers throughout Russia including Ural,

Siberia, Poland and Baltic countries. Since centuries malignant tumors are treated

with chaga or Phellinus nigricans. E. Froben, a physician, from Russia reported

recession of parotid gland cancer upon treatment with Piptoporus betulinus

decoction. Moreover, Russians also used puffballs

(Lycoperdon and Calvatiaspecies) with hot wine to treat constipation. Mushrooms

also were used to cure livestock (Denisova, 1998).

Various volumes as the materia medica compiled by Li Shi-Zhen of the

Ming Dynasty highlighting more than 20 mushrooms (Bensky and Gamble, 1993),

now totals around at least 270 species of mushroom for various therapeutic

properties (Ying et al., 1987). Live ethnomycological practices in India (Natrajan et

al 2006) spanning from “Phanasomba” under the Ayurvedic regime to other

ethnomycological practices from central India (Vaidya et al., 2000; Harsh et al.,

1999; Rai et al., 1993), calls for a strategic investigations evolving from

ethnomycological practices to pharmacological evaluations.

1.3 Commercial scenario of medicinal mushrooms

The value of medicinal mushrooms along with their derivative dietary supplements

on global scale had increased 5 folds from US $1.2 billion in 1991 (Chang, 1996)

to, a considerable US $6 billion in 1999 (Wasser, 2000). The total global

production of edible and medicinal mushrooms escalated from 1.2 million tons in

1981 to an estimated 7 million tons in 1999 and approximately 9.9 million tons in

2004 (Casey, 2008). Thus is almost two decades the global production of

mushrooms increased c.a. eight times.

In 2004, the estimated value of wild edible mushroom gathering was $2

billion (Boa, 2004). In Washington, Oregon and Idaho sales reached $41.1 million

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INTRODUCTION

Chapter-1 in 1992 (Schlosser and Blatner, 1995). Trade of species like Cantharellus

formosus, C. subalbidus, T. magnivelare and Morchella spp. is an alternative

activity that complements local earnings, in the US Northwest, where the wood

industry is restricted (Pilz et al., 1999).

USA alone produced around 400,000 tons of Agaricus species in 2006

fetching $915 million that was 8% more than the previous crop year. Import of

mushrooms witnessed a 30% increase from the year before at $236 million for the

first 10 months of 2007. Though the speciality or medicinal mushroom accounted

for $40 million of the total in 2006, the initial leap was 400% from 2 to 8 million

pounds in a single crop year. The medicinal ones are catching up at a fast pace

as the bulk sales of Agaricus blazei of Torrance Ltd. alone has shot up 300%

within 2003 and 2007 (Casey, 2008).

Recognition of polysaccharides from mushrooms as anticancer agents,

other constituents exhibiting antioxidants, anti-hypertensive, cholesterol-lowering,

liver protection, anti-fibrotic, anti-inflammatory, anti-diabetic, anti-viral and anti-

microbial like activities, has overtly primed its potential as dietary supplements

(Zjawiony, 2004). They are designed to supplement the human diet, not to be

used as a regular food, by increasing the intake of bioactive compounds for the

enhancement of health and fitness. While more than 600 mushroom species have

revealed immune stimulation effects, commercial focus is still on medicinal

mushrooms like Grifola frondosa, Lentinula edodes, Ganoderma lucidum,

Coriolus versicolor, Agaricus blazei, Cordyceps sinensis, Hericium erinaceus and

Schizophyllum commune (Casey, 2008). US diet-supplement sales moved from

US$3.3 billion in 1990 to US$ 14.0 billion in 2000 (Zeisel 1999). Commercial

interest on "mushroom nutriceuticals" compounds that is used in the prevention

and treatment of various human diseases is increasing dramatically (Chang and

Buswell, 1996). The focus is majorly on the following species with specific

therapeutic potentials (Francia et al., 1999).

Total cholesterol reduction: Auricularia auricula-judae, Cordyceps sinensis,

Ganoderma lucidum, Grifola frondosa, Pleurotus ostreatus, and Tremella

fuciformis

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INTRODUCTION

Chapter-1 Low-density lipoprotein reduction: Auricularia auricula-judae and Tremella

fuciformis

Triglyceride level reduction: Cordyceps sinensis, Grifola frondosa, and Lentinua

edodes

Platelet binding reduction: Auricularia auricula-judae, Calyptella sp., Ganoderma

lucidum, Kuehneromyces sp., Neolentinus adhaerens and Panus sp.

Blood pressure reduction: Ganoderma lucidum, Grifola frondosa and Tricholoma

mongolicum

Glycemia reduction: Agaricus bisporus, Agrocybe aegerita, Cordyceps sinensis,

Tremella aurantia, Grifola frondosa and Coprinus comatus

Grossly speaking these species accounted for a US$3.6 billion industry in

1994 (Chang, 1996) and in 1995 G. lucidum alone accounted for a sale of about

US$1,628.4 million. The market values of the mushroom products were estimated

to be US$350 million in China, US$600 million in Korea, US$300 million in Japan,

US$215 million in Taiwan, US$91.2 million in Malaysia, US$60 million in Hong

Kong, US$2.2 million in Singapore and US$10 million in other countries (Chang

and Buswell, 1999).

The output of China’s edible mushroom increased from 1000 million

kilogram in 1978 to 14.7 billion kilogram to 2006, which is 3 times in less than 30

years accounting for 70% of the worlds’ total (Ziqiang, 2009). There was a

phenomenal increase in Chinese edible mushroom export (1.121billion dollar) in

2006, which escalated to 1.45 billion in 2007 and then 1.424 billion in 2008 (Hui,

2009). But this plummeted under the influence of the economic meltdown that

decreased the demand of medicinal and edible mushrooms by 40 – 20% (Ziqiang,

2009).

1.4 Natural products in drug discovery

Ethnopharmacological studies are generally based on anthropological

appropriations of natural resources that are propagated across several

generations endowing it traditionality, which if delved deeper regarding its mode of

actions may result in discovery of novel medicines (Patwardhan, 2005).

NAPRALERT a database withhold above fourteen thousand ethnomedical

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INTRODUCTION

Chapter-1 species which is only about 5% of the total estimated biodiversity. On the other

hand only 42% of the reported species are bioprospected leaving a large room for

exploration (Cordell and Quinn-Beattie, 2005). In addition to this one-half of the

anti-cancer drugs developed since 1960 (Kim and Park, 2002), and over 100

other successful pharmaceuticals (Farnsworth, 1994) are from natural resources. A recent survey revealed that 61% of the 877 drugs introduced worldwide

can be traced to or were inspired by natural products (Rouhi, 2003a). Natural

product drug discovery plummeted post combinatorial chemistry (Cseke et al.,

2004), which has given moderate outputs. The number of new drugs entering the

market has dropped by half, a figure of which the large pharmaceutical

corporations are painfully aware. Of the roughly 3,50,000 species of plants

believed to exist, one-third of those have yet to be discovered but at the same

time, habitat loss is the greatest immediate threat to biodiversity (Rouhi, 2003b).

Global sales of prescription pharmaceutical products are estimated to

exceed $330 billion and 57% of the top 150 prescription drugs contain active

ingredients that are pure natural products, synthetic derivatives or chemical

analogs of natural products (Grifo et al., 1997). Contradictorily the innate value of

such natural resources as plant, animal, and microbial products directly used in

the manufacture of prescription pharmaceuticals is estimated to be less than $12

billion (Ortega, 1998). Biodiversity is also a source of novel compounds for the

discovery of new drug leads, and pharmaceutical companies annually spend more

than $45 billion on research (Mathieu, 1998). But screening of natural and

synthetic compounds accounts for less than 12% of the research expenditures

because most of these resources are spent on equipment and manpower costs

rather than acquisition of compounds (PhRMA, 1999).

Skin care products containing biologically derived antioxidant, analgesic,

antibacterial and anti-inflammatory agents are a growing segment of this market.

One study estimated US sales of naturally derived personal care products to

account for $2.5 billion of the $28 billion US market. But, the value of the

biological source material used in these products was estimated at less than $500

million (Artuso, 2002).

About 60% of the drugs that are now available-including household names

such as artemisinin, camptothecin, lovastatin, maytansine, paclitaxel, penicillin,

reserpine and silibinin-were either directly or indirectly derived from natural

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INTRODUCTION

Chapter-1 products (Newman, 2008). As estimated by the World Health Organization almost

80% of the people rely mainly on traditional medicines for their primary health

care (Farnsworth et al., 1985). The continuum of new chemical entities (NCEs)

comprised of 877 small molecules (1981-2002), of which 67% were formally

synthetic but 16.4% correspond to synthetic molecules containing

pharmacophores and 12% were actually modeled on a natural products leaving

behind only 39% as truly synthetic (Newman et al., 2000).

1.5 Ecological bioprospecting aspects of plant para sitic macrofungi make

way for ethnomedicinal rationales

The inhabited earth is flooded with all sorts of life forms that compete for

resources. Thus in order to occupy a particular ecological niche the organism is

ought to be loaded with arsenal of counteracting metabolites that facilitate its

establishment. Under the co-evolutionary phenomenon the plants that evolved

antimicrobials were able to defend themselves against pathogenic bacteria;

pathogens that evolved resistance mechanisms, such as multi drug resistance

pumps, were able to break plant defenses; in turn, plants that developed multi

drug resistance inhibitors had a significant evolutionary advantage (Li & Zhang,

2008). This was reestablished when highly potent antimicrobial drug of Berberis

spp. (Pepperidge bush) was found to be due to its antimicrobial agents. But there

was a drastic reduction in potency when administered in pure form, because the

crude form of extracts had multidrug-resistance (MDR) inhibitors such as 5’-

methoxyhydnocarpin (Stermitz et al, 2000). Thus unlike allopathic regime,

ethnomedicinal regimes do not administer highly purified botanicals. By

administering crude preparations the traditional practitioners have been able to

suppress resistance and even toxicity. Aligning our research on these lines the

stress was on characterizing the active fractions rather than purifying individual

molecules.

On another axis, according to the hypothesis of xenohormesis, the

common ancestor of plants and animals were able to synthesize a large number

of stress-induced secondary metabolites but animals and fungi that feed on plants

gradually lost the capacity to synthesize some of these low-weight molecular

compounds. But they retained the ability to sense these chemical cues, possibly

in order to detect when plants were stressed and gain an early warning of

changing environmental conditions (Howitz and Sinclair, 2008). Thus reception of

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INTRODUCTION

Chapter-1 several metabolites not produced became all the more important. A comparative

genomic analysis revealed that 70% of cancer-related human genes have

orthologues in Arabidopsis thaliana (Jones et al, 2008). This ensures the cross

reactivity of several plant metabolites that were originally produced to modulate

their own metabolism and eventually end up bearing therapeutic potentials.

Moreover certain multidrug resistance-like proteins that are used by Arabidopsis

to transport auxin have orthologues in humans that are crucial for the transport of

anti-cancer agents; auxin-distribution modulators such as flavonoids from

Arabidopsis can inhibit P-glycoprotein (MDR1) in various human cancer cells

(Taylor & Grotewold, 2005).

Thus by co-evolutionary principle the plant parasitic macrofungi are known

to successfully infest the host heart wood. In order to launch and succeed in such

an insurgence the macrofungi is expected to overcome several challenges put

forth by the host. Moreover, according to the xenohormesis theorem, several plant

receptors and targets that may be attended by the macrofungi may have

homology with human counterparts. This paves the way for the rationale and

professes the plausible therapeutic potential of several bioactivities of

macrofungal metabolites. There are several studies which are based on mycellial

extracts of these macrofungi, but certain secondary metabolites are only

biosynthesized only in the fruiting body stage. Hence mycellial extracts may not

contain these molecules which the macrofungi prodices to forcefully establish

itself as a pathogen. The xenohormesis hypothesis implies that these

pathogenesis related macrofungal metabolites that are used against the host

might have better chances to work in human or mammalian-based in vivo models.

This piece of work was thus based on these rationales and in order to strengthen

its foundation, ethnomycomedicinal practices were aimed at, which ensues

clinically validated practices.