Description
Ellner et al1, in an effort to rationalise the types of media required for different work developed Columbia Agar. A blend of casein hydrolysate to provide rapid and luxuriant growth, and various infusion media for more sharply defined haemolytic reaction, typical colonial morphology and improved pigment production was eventually established. Originally employed as a blood agar base, Columbia Agar without supplements, will support the growth of Brucella abortus, Clostridium perfringens, Yersinia species, Enterobacteriaceae and most clinical micro-organisms. Starch was included in the formula as it was found to increase the growth of Neisseria and enhance the haemolytic reactions of some streptococci2.
“Chocolate” Agar prepared from Columbia Agar Base produced more rapid and luxuriant growth of gonococci and Haemophilus influenzae than on comparable media1.
Thayer Martin Medium3 for the selective isolation of Neisseria meningitidis can be prepared by the addition of Colistin 7.5 ug/ml and Vancomycin 3U/ml to chocolate agar.
