COLUMBIA BLOOD AGAR (MEDIUM Q) (as per BP)

Description

Columbia Blood Agar Base used as a general-purpose nutritious medium was devised by Ellner et al from Columbia University, which was further enriched by the addition of sheep blood. It can also be used for the isolation of organisms by addition of various supplements. Columbia Agar is prepared as per the formulation in BP and is in accordance with the microbial limit testing harmonized methodology of USP/BP/EP/JP. This medium is recommended to check the presence of Clostridium in non-sterile products like food, dietary, nutritional supplements related products. The genus Clostridium belongs to the family Clostridiaceae in the class Clostridia. The product to be examined is initially enriched in Reinforced medium for clostridia. This medium contains 0.05% Agar and cysteine, which creates anaerobic conditions, thereby allowing anaerobic organisms to grow. The enriched sample is then subcultured on Columbia Agar. Columbia Agar is used as a base for media containing blood and for selective media formulations in which different combinations of antimicrobial agents are used as additives. Clostridia grows under anaerobic conditions as gram positive rods giving a catalase negative test. Further confirmation is carried out by identification tests.