bmic topic 3.3 microbiological media: chemical composition

part 2

what is defined media?

made from known components
exact composition is known
exactly duplicated

what is undefined media?

contains natural products
exact composition unknown
impossible to duplicate exactly
batch to batch variation in both media and culture

what are the natural products?

water soluble extracts
digest of proteins

what are examples of water soluble extracts?

beef yeast soil extracts

what do water soluble extracts provide?

vitamins, organic growth factors
organic carbon and nitrogen
coenzymes and nucleosides
minerals

what are examples of digests of proteins?

peptone
tryptone

what do digests of proteins provide?

amino acids
organic carbon, nitrogen and sulfur

what are some other natural products?

blood and serum

what do the other natural products provide?

complex growth factors for fastidious microbes