G.C. Agar Base

Product information

A nutritious agar base described by Thayer and Martin for the isolation of Neisseria gonorrhoeae. The rich peptone mixture is enhanced by the use of corn starch to absorb toxic metabolites and a buffering system is used to maintain neutral pH. The medium is made selective by the use of various antibiotic cocktails. Thayer and Martin originally recommended the use of vancomycin, colistin and nystatin V.C.N. but the addition of trimethoprim (X068, X268 V.C.N.T.) is useful in preventing the swarming of proteus. More recently the emergence of vancomycin sensitive gonococci has made the New York City selective agents (lincomycin, colistin, amphotericin, trimethoprim X070, X270 LCAT) the combination of choice. Enrichment of the base is usually by the addition of lysed blood. Alternatively chocolated blood or haemoglobin powder and Thayer and Martin’s mixture of vitamins, amino acids and coenzymes can be used. The supplement X069, X269 can be added as this is without Amphotericin and this permits the growth of yeasts. The growth supplement X271 can be added to this medium to aid in the isolation of Neisseria spp.