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Aurora
ferred to as agar+
According to function culture media are categorized into following categories,
Nutritive media
Selective media
Differential media
Specialized media/ enriched media
Enriched non selective media
Non selective media are designed to support the growth of most organisms without specific growth requirements that are needed to cultivate some organisms+ Some organisms
require a specific condition to grow which will be discussed in upcoming chapters+ Most of
the above mentioned bacteria can grow in these mediums+
The following are some of the more commonly used media:
Blood agar:
Many types of blood agar media are used in clinical laboratories+
The media contain two primary components
1+ A basal medium (e+g+, tryptic soy, brain heart infusion,
Brucella base)
2+ Blood (e+g+, sheep, horse, rabbit)+
Various other supplements can also be added to extend the
range of organisms that can grow on the media+ This medium can be used to grow bacteria with hemolytic properties+
eg: staphylococcus, corynebacterium diphtheria ,vibrio cholera
Preparation Ingredients:
Base of growth containing, a protein source (e+g+ Tryptones), Soybean protein digest, Sodium chloride (Nacl),
agar and 5* sheep blood+
Pancreatic digest of casein
Papaic digest of soy meal
NaCl
Agar
Distilled water
Fig 1.15: Blood agar (Foster. D;
Chen.J, 2015)
Procedure:
1. Sterilize the glassware by autoclaving at 121oC for 15 minutes+
2. Combine the ingredients and adjust the pH to 7+3+
3. Boil to dissolve the agar
4. sterilize the agar by autoclaving+
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