Download - Culture media
THE USE OF APPROPRIATE CULTURE MEDIA FOR THE
IDENTIFICATION OF BACTERIA
Made by : Group# C1
Fasahat Ahmed Butt (36)
CULTURE MEDIA A culture medium is a compound , which
has constituents that are essential for life , multiplication and growth of micro-organisms.
1) Nutrients
2) Mineral salts
3) suitable pH
4)Accessory growth factors
CLASSIFICATION OF CULTURE MEDIA
ACCORDING TO PHYSICAL STATE
(A) LIQUID MEDIUM:1) Peptone water2) Nutrient Broth
(B) SOLID MEDIUM: 1) Nutrient agar
ACCORDING TO CONSTITUENTS
Simple media Enriched media Differential media Selective media Transport media
SIMPLE MEDIA
Consists of only basic substances such as, nitrogen , carbon , minerals.
EXAMPLES: Nutrient broth Nutrient agar Peptone water
ENRICHED MEDIA
Some enriched material like blood and serum is added to the medium , required for proper growth of some bacteria
EXAMPLES: Blood agar Chocolate agar
DIFFERENTIAL MEDIA
This type of media is used to differentiate between two groups of bacteria .
EXAMPLES: MacConkey’s medium
SELECTIVE MEDIA
An inhibitory substance is added to the media which prevents growth of all organisms except the one for which it is designed.
EXAMPLES: Loweistein jensen’s medium
TRANSPORT MEDIA A media used to transport specimen to
keep the organism alive EXAMPLES: AMIE’s medium
HOW TO IDENTIFY BACTERIA’S USING CULTURE MEDIA ????
NUTRIENT AGAR
MICRO-ORGANISMS CULTURED: Staph.aureus golden yellow
colonies Staph.citrus lemon yellow
colonies Pseudomonas green colonies
BLOOD AGAR
MICRO-ORGANISMS CULTURED: Complete (beta) hemolysis: Strep.pyogenes In complete (alpha) hemolysis: Streptococcus pnuemonia Non-hemolytic : staph.aureus and staph.citrus
CHOCOLATE AGAR
MICRO-ORGANISMS CULTURED: 1)H.influenza 2)Neisseria.meningitidis
MACCONKEY’S MEDIUM MICRO-ORGANISMS CULTURED: 1) lactose fermenters (pink colonies): E.coli. 2) non-lactose fermenters (colour less
colonies): shigella
LOWENSTEIN-JENSEN MEDIUM
MICRO-ORGANISMS CULTURED: Mycobacterium tuberculosis