COLUMBIA AGAR BASE (Eur. Pharma.) 500 grams/bottle

Columbia Agar Base is a highly nutritive general purpose medium for the cultivation of fastidious organisms, especially when used as a base for Blood Chocolate Agar. It can also be used as a selective isolation medium by adding antimicrobial agents. It is suitable for the isolation and cultivation of a wide variety of microorganisms with difficult growth characteristics. By adding blood, it can be used to determine hemolytic reactions. The majority of the common pathogenic bacteria, however, grow well without the addition of blood. Pancreatic digest of casein, meat peptic digest and Heart pancreatic digest provide nitrogen, vitamins, minerals and amino acids essential for growth. Yeast extract and maize starch are a source of vitamins, particularly of the B-group essential for bacterial growth. Sodium chloride supplies essential electrolytes for transport and osmotic balance. Bacteriological agar is the solidifying agent. The blood is another source providing growth factors for the microorganisms and is the basis for determining hemolytic reactions. Hemolytic patterns may vary according to the type of blood or base medium used. For example, defibrinated sheep blood gives best results for Group A streptococci. To make the medium more selective, the following supplements may be added if desired: CNA Staph/Streph Supplement (Cat. 6016) for staphylococci, streptococci and pneumococci isolation. Brucella Supplement (Cat. 6017) for Brucella isolation. The European Pharmacopoeia, USP, recommends the Agar Columbia in the Paragraph 2.6.13 Microbiological examination of non-Sterile products: test for specified microorganisms for the testing of Clostridia in products. ISO 10272 indicates that Columbia Agar Base with blood can be used to allow the development of well-isolated colonies, to use these colonies in confirmation tests. With the addition of 5-10% sterile defibrinated blood and, especially with Polyenrichment Supplement (Cat. 6011) and VCN Supplement (Cat. 6013), Columbia Agar Base becomes an excellent chocolate agar that can be used to isolate pathogenic Neisseria, gonococci and meningococci, as good as or better than Thayer-Martin Medium. Depending on the selection of inhibitors, alternative supplements to VCN may be VCNT (Cat. 6026) or VCAT (Cat. 6014).