Rapid growth and increased biomass yield of Mycobacterium farcinogenes and some related taxa in broth and agar media.

A broth medium containing yeast extract (4 g/l), glucose (15 g/l), magnesium sulphate (0.5 g/l), tri-sodium citrate (1.5 g/l), potassium sulphate (0.5 g/l), ammonium ferric citrate (trace) and buffered with potassium di-hydrogen phosphate (5 g/l) was formulated and found to support a luxuriant growth of Mycobacterium farcinogenes strains that was superior to the conventional media used before. Similar results were obtained with M. senegalense strains and with representatives of the genera Gordona, Mycobacterium, Nocardia, Rhodococcus and Tsukamurella. Out of 13 diverse agar-based media, M. farcinogenes was found to grow particularly well on Mueller Hinton's medium, followed, in order of decreasing growth rate, by modified Bennett's, DST, tryptic soya and glucose yeast extract agars.