For isolation, cultivation and detection of haemolytic activity of Streptococci, Pneumococci and other fastidious microorganisms. BLOOD AGAR BASE No 2 is a base medium rich in nutritional properties, used for the preparation of blood agar plates. It is used for the isolation, cultivation and recovery of fastidious microorganisms to study hemolysis activity. Microorganisms producing haemolysin give visible haemolytic zones on this medium. This medium can be used to prepare a selective medium for Brucella spp or Campylobacter spp by adding an antibiotic supplement. It may also be used for the primary isolation of Haemophilus spp. Add horse blood to enrich the medium.
Medium contains Liver extract which helps to enhance the growth and haemolytic reactions of fastidious organisms like Streptococci and Pneumococci. Proteose peptone serves as the nitrogen source while liver digest and yeast extract provide essential carbon, vitamin, nitrogen, amino acid sources. Sodium chloride maintains the osmotic equilibrium. Whereas agar act as solidifying agent. Supplementation with blood (5-10%) provides additional growth factors and also serves as basis for determining haemolytic reactions. Haemolytic patterns may vary with the source of animal blood or type of base medium used.