MLS

TYPES OF CULTURE MEDIA BASED ON OXYGEN REQUIREMENT.

Microorganisms have different requirements for growth depending on oxygen requirements.

1. Aerobic media
In this media, it is easy to cultivate microbes, on solid media, the growth occurs by keeping the culture in the incubator. It shows the growth; of non-fastidious microorganisms.

Examples of aerobic media are- liquid media, solid media

Peptone water- 1%peptone + 0.5% Nacl +100ml water.

Nutrient agar- nutrient broth +2% agar.

2. Anaerobic media
The media cultivates anaerobic bacteria at low oxygen, reducing oxidation-reduction potential. Anaerobic media contains extra nutrients like vitamin K, hemin, and oxygen that get reduced by a physical or chemical process. The addition of glucose (1%), thioglycollate(0.1%), ascorbic acid (0.1%), cysteine (0.05%), or iron fillings added to cause the medium to reduce. The medium is boiled in a water bath to force out dissolved oxygen and packed with sterile paraffin.

Examples of Anaerobic media:

RCM (Robertson cooked meat) isolation for Clostridium sp.

Thioglycolate broth– It has sodium glycolate that maintains low oxygen.