Microbiology Task 2

7/28/2019 Microbiology Task 2

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TASK 1

MICROBIOLOGY PHARMACY

Growth MediaWWRRIITTTTEENN BBYY:

IKA YULIA RIZKI

1111012053

Lecturer : Prof. DR. Marlina, M.Farm, Apt

PHARMACY FACULTY

ANDALAS UNIVERSITY

PADANG

2012


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MEDIA CLASSIFICATION AND BACTERIAL

NUTRITIONAL REQUIREMENTS

DefenitionMedia is a material consisting of a mixture of nutrient (nutrients) that are useful for

culturing microbes. By using a variety of media to do the isolation, propagation, testing and

calculation of a number of physiological properties of microbes. So that microbes can grow well

in a medium, the medium must meet the requirements, among others: should contain all thenutrients are easily used by microbes, must have an osmotic pressure, surface tension and pH

in accordance with the needs of the microbes that will grow, not contain substances that can

inhibit microbial growth, must be in sterile condition before being used, so that the microbe

can be grown successfully grown

media serves to cultivate microbes, isolation, increase the number, examine the properties and

the calculation of the amount of microbial physiology, which should be sterilized in the manufacturing

process and apply the aseptic methods to avoid contamination of the media. Nutrient medium that is

common to test the water and dairy products. NA is also used for the majority of the growth of

microorganisms that are not selective, in terms of heterotrophic microorganisms. Media is a simple

media made from beef extract, peptone, and agar. NA is one of the media commonly used inbacteriological procedures such as regular testing of water, sewage, food products, to bring the stock

culture, to the growth of bacteria on the test samples, and to isolate the organism in pure culture with

caradisterilisasi by autoclaving at 121 C for 15 minutes (Fathir, 2009).

Using Selective, Differential and Selective-Differential Media in the isolation and

identification of individual bacteria

Bacteria must be isolated from their natural environments before they can be characterized. As

bacteria exist in mixed populations in the soil, water, food and within or on the human body, specialized

media are often used to isolate individual bacteria from these populations and to characterize the

isolated bacteria.

Selective media are used to select for the growth of some bacteria while inhibiting the growth

of others. Such media take advantage of the differences in the nutritional needs of individual bacteria

or exploit the ability of some organisms to grow in the presence of a noxious compound. For example,

Pseudomonas aeruginosa is able to grow in the presence of a variety of antibiotics (compounds that

inhibit bacterial growth or kill bacteria) while organisms like Staphylococcus aureus or Escherichia coli

are sensitive to these antibiotics.


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Differential media allow a variety of organism to grow but contain substances that allow the

student to distinguish between the different types of bacteria growing on the media.

Starch Agar: This is a differential medium used to determine whether a given bacterium is able

to use starch as a carbon source and an energy source. Starch is a polymer (polysaccharide) of

repeating glucose monomers and is too large to be transported into the cell. Organisms that use starch

produce an exoenzyme called alpha-amylase that breaks the bonds between the glucose monomers

such that the glucose monomers can be taken up into the cell and catabolized. Alpha-amylase is

secreted outside of the cell but is still active at this location. To determine if the organism produces this

exoenzyme, one adds Grams Iodine to the plate that turns the intact starch in the medium purple. If

the organism utilizes starch, the area around the colony will be clear because, the starch has been

broken down into glucose monomers (starch positive). If the organism does not utilize starch then the

media surrounding the organism will be dark purple (starch negative.

MacConkey Lactose Agar: This is a selective-differential media that selects for the growth of

enteric bacteria. Enteric bacteria are gram-negative rods that are facultatively anaerobic. Enterics are

most commonly found in the gastro-intestinal tract of humans and include E. coli, Serratia spp. and

Salmonella spp. Enterics grow on MacConkey media because the bile saltsthat are present in the

media inhibit the growth of non-enteric organisms while the crystal violet inhibits the growth of Gram

positive organisms that might otherwise grow on this media. MacConkey media also differentiates

between the noncoliforms and the coliforms that also grow on this medium. Enteric bacteria can be

coliforms or noncoliforms. Enteric bacteria that ferment lactose to form acid and gas are coliforms,

enteric bacteria that do not ferment lactose are noncoliforms. Coliforms will produce bright pink

colonies on MacConkey lactose agar because a pH indicator (methyl red) is present in the media. The

non-coliforms will grow on the media but the colonies will appear either light yellow or colorless.

Hektoen Enteric Agar: This is also a selective-differential media that contains bile salts to select

for enteric organisms but distinguishes between these enterics by virtue of their abilities to ferment

lactose, salicin or sucrose and to reduce sulfur to hydrogen sulfide gas. In addition to these

fermentable sugars, H-E Agar contains ferric ammonium citrate that reacts with the hydrogen sulfide to

form a black precipitate and the dyes acid fuchsin and bromothymol blue that are color indicators. This

media is often used to isolate Salmonella and Shigella spp from other enterics. The enterics that

ferment the sugars produce acids and form yellow to pink colonies on this medium. Shigella and

Salmonella spp.do not ferment these sugars and produce blue colonies. Salmonella spp. (but not

Shigella spp.) reduce sulfur to hydrogen sulfide forming colonies containing a black precipitate.

Selective-Differential Media have characteristics ofboth selective media and differential media.

These media only allow a subset of bacteria to grow and allow the student to distinguish between the

different types of bacteria that are able to grow on these media. For example, one can distinguish

between bacteria that ferment lactose and those that do not in MacConkey Agar by adding a carbon


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source (lactose) and a pH indicator (methyl red)bacteria that ferment lactose produce acids that

imparts a color change to the media surrounding the individual bacterial colony.

Type of MediaMedia is divided into:

1. Media General, the media can be used for the growth and proliferation of one or more groups of

microbes in general.

2. Media add-on, which is used to mean "an opportunity" to a species or group of microbes to grow

rapidly.

3. Selective media, ie media that can only be covered by one or more types of specific microbes but will

inhibit or shut off for other types.

4. Differentiation media, the media used for testing a compound or a particular object with the help of

microbes.

5. Media testers, the media used for testing a compound or a particular object with the help of

microbes.

6. Enumeration media, ie media that is used to calculate the number of microbes in a material.

(Suriawiria, 2005).

Based on the consistency or density, the medium is divided into three types, namely:

a. Liquid medium / broth / liquid medium

Example: water peptone, nutrient broth, lactosa

b. Semi-solid medium (semi-solid medium)

Example: sim agar, and brain in order to cary

c. Solid medium (solid medium)

Example: endo agar, PDA, Nutrient order

The outline of the manufacture of medium that is composed of several ingredients are as follows:

a. Mixing materials - materials, dissolved in distilled water and heated in a water heater so that a

homogeneous solution.

b. Filter with filter paper, cloth, or cotton. To order or gelatin media, filtering should be done in hot

conditions.

c. Determine and adjust the pH.d. Insert media into a certain place. Before sterilized, media inserted into the erlenmeyer or other clean

container, then close the cover of cotton or paper (parchment paper) that is not wet when sterilized.

e. Sterilization is generally performed with hot air in the autoclave at a temperature of 1210 C for 15-30

minutes

(Sutedjo, 1991).

PH is a factor that greatly affects the success in the manufacture of medium so that the pH is too

alkaline or too acidic medium is not suitable to serve as microbes because microbes can not live in these


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conditions. Medium silenced or kept for 2 x 24 hours to assure that the medium is sterile, because in

addition to pH as a determinant of the growth of microbes, tools and a sterile medium also determines

(Dwidjoseputro, 1994).

Preparation of MediaTo investigate the bacteria in the laboratory, we must be able to grow them in pure culture. To do

this, one must understand the types of physical environments that provide the optimum conditions for

growth. In the laboratory, the physical environment in question is the culture media.

Sterile culture media is the medium used to grow microorganisms. Culture media consisting of an

organic salt, a source of energy (carbon), vitamins and growth regulators (PGR). Moreover, it can also

add other components such as organic compounds and other complex compounds (Soeryowinoto,

1985). Wide diversity in terms of nutrients between bacteria type, offset by the availability of variousmedia for many kinds kultuivasinya. Kinds of media can be divided based on the shape and composition.

based on form, media divided over medical liquid, semi liquid and solid. Being according to its

composition, the media can be divided into complex medium and synthetic media. As in this

experiment, the type of media used is a type of media PDA (Potato dextrose order) that are classified as

solid media and complex media.

Culture media capable of supporting the optimization of growth milroorganisme should be able to

meet the requirements of nutrients for microorganisms. element in the form of organic salts, energy

sources (carbon), vitamins and growth regulators (PGR). Moreover, it can also add other componentssuch as organic compounds and other complex compounds (Soeryowinoto, 1985).

Types that include inorganic salts, especially potassium nitrate form of nitrogen (KNO3), sulfur

(inorganic sulfur), phosphorus and inorganic metal elements such as sodium, potassium, kalsiuum,

magnesium, manganese, iron, zinc, copper, and cobalt . The element carbon that is used by

microorganisms can be either emitted or light dinamankan fototrof, and the other is kind of kemototrof

using the oxidation of chemical compounds in the media to obtain energy (Hadioetomo, 1986).

Function of vitamins in the culture media to form a substance that activates the enzyme.

Microorganisms show different symptoms making patterns dala nutrients. Although all microorganismsrequire vitamins in metabolic processes, but some types of microorganisms Nampu synthesize their own

vitamin requirements of other compounds in the medium. These vitamins are often added in the culture

medium are: niacin, glycine, pyridoxine, hydrochloride, Thiamine, folic acid, etc. (Soeryowinoto, 1985)

On plant growth regulators are organic compounds rather than nutrients, which in small amounts

but can support, inhibit, and alter the plant physiology. Growth regulator is required as a component for

the growth and differentiation medium, without the addition of growth regulators in the medium, the


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growth of microorganisms is hampered even may not be able to grow at all (Gardener, 1993).

PDA medium (Potato Dextrose order) are the sorts of substances used in organic nutisi culture

medium. This material is commonly used in the composition of the culture lanortorium! 0:1:1 potato,

dextrose and order in 1 liter of distilled water .PDA (Potato Dextrose order) is a common medium used

in cultivation of bacteria. In addition to its manufacturing process is easy, also because it has a complex

composition for the growth of bacteria, namely nerupa (Hendaryono, 1994).

Culture media there is a solid, liquid and semi solid. Solid media is a media culture that solidified

with agar, there is a reversible (reversible) such as nutrient agar, and there are ireversible (not

reversible) such as blood serum terkoagulasi. In medicine, solid media are used most often irreversible.

Nutrient being so widely used in other media.

Other forms of media in the form of a liquid is a mixture of the components of certain chemicals

with distilled water, the media is physically an intermediate between liquid and solid media, such as for

software. Media is complex and there are synthetic. Synthetic media is media that all components are

chemicals that all components are chemical-specific tangible and less obvious in terms of its content or

can not be ascertained, often termed a complex medium. Complex nutrient medium such as that

prepared by dissolving each ingredient is needed or even easier by adding water to a commercial

product that has been shaped powder medium contains all the nutrients it needs. On practical, all

nutrients are commercially in powder form and also in the form of ready-made in a Petri dish, cup, jar or

bottle (Hasioetomo, 1986)

Experiment MethodologyTools

The tools used in these experiments is Erlenmeyer, volume pipettes, autoclave, measuring cups,

analytical balance, magnetic stirer, hot plate, and test tubes.

Materials

The materials used in these experiments is the media Nutrient Agar, Malt Extract Agar, Potato Destroxe

order, and distilled water.

Work Procedures

a.Preparation of Media Nutrient Agar (NA)

A. Created NA media (20 g / L) was mixed with 5 grams peptone, meat extract as much as 3 grams, and

order as much as 12 grams into the erlenmeyer.

2. Added 50 mL of distilled water. produced by NA as much as 1 gram.

3. Heated on a hot plate to boil while stirring with a magnetic stirer until homogeneous, then left for

some time.

4. Put into 3 test tubes of each of 4 mL

5. Capped reaction tubes using a cotton mouth


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6. Included in the autoclave to be sterilized along with the tools to be used at temperatures of 121oC

and a pressure of 15 psi.

b. Making Potato Destroxe Agar (PDA)

A. Created media PDA (39 g / L) was mixed with potato as much as 4 grams, as much as 20 grams of

glucose, and order as much as 15 grams into the erlenmeyer.

2. Added 50 mL of distilled water. Produced up to as much as 1.95 grams of PDA.


some time.

4. Put into 3 test tubes of each of 4 mL.




c. Media Making Malt Extract Agar (MEA)

A. Created MEA medium (48 g / L) was mixed with as much as 3 grams of peptone, meat extract as much

as 30 grams, and the order of 15 grams into the erlenmeyer.

2. Added 50 mL of distilled water. Until the MEA produced as much as 2.4 grams.


some time.

4. Put into 3 test tubes of each of 4 mL





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Reference

Barker, Kathy. 1998.At The Bench, A Laboratory Navigator. Cold Spring Harbor Laboratory Press, New

York.

Barrow, G.I. and R.K.A. Feltham. 1993. Manual for the Identification of Medical Bacteria. Cambridge

University Press, New York

Beishir, Lois. 1991. Microbiology in Practice : A Self Instructional Laboratory Course. Harper Collins

Publisher Inc., New York

www.microbiology.mtsinai.on.ca

Documents

Microbiology Task 2