Definition of culture media
The food material or the substance required for growing microorganism in-vitro(outside the body) is called culture media.
Uses of culture media
• To identify the cause of infection from the
clinical sample so that the proper treatment
can be given
• To study the characteristics of the
properties of microorganism.
• To prepare biological products like
vaccines toxoids ,antigen etc.
•For antibiotic assays
Characteristics of an ideal culture medium
• Satisfactory growth from small
inoculum
• Demonstrate all the character that we
required
• Easily reproducible
• Rapid growth
Basic requirement of culture media
• Energy source
• Carbon source
• Nitrogen source
• pH satisfactory PH
• Growth factors
• Adequate oxidation- reduction
potential.
• Salt such as sulphate, phosphate, chloride.
and carbonates of k, Na,Mg,Ca,fe.
•Constituents of culture media
1) Water - source of hydrogen and oxygen.
2) Electrolyte -NaCl or other electrolyte.
3)Peptone - complex mixture of partially
digested protein.
4) Meat extract - available commercially as" lab -lemco." It
contains proteins degradation products ,inorganic salts,
carbohydrates,and growth factors.
5) Yeast extract - It is prepared commerically from
Bakers'yeast.
6) Blood or serum - These are used for enrching culture media.
7) Agar - It is prepared from sea weed.
Classification of Culture Media
1) Based on physical state.
2)Based on oxygen requirement.
3) Based on Nutritional factors.
1) Based on physical state
1) Solid media
2) Liquid media
3) Semisolid media
2) Based on oxygen requirement
1) Aerobic media
2) Anaerobic Media
3) Based on Nutritional factors
1) Simple Media
2) Complex Media
3) Synthethic Media
4) Special Media
a) Enriched media
b) Enrichment media
c)Selective media
d)differential media
e)Indicator media
f) Transportmedia
g) sugar media
