Rifomycin. XIV. Production of rifomycin B.

The production of a fraction of the rifomycin complex (rifomycin B) by Streptomyces mediterranei has been described. Both qualitative and quantitative aspects of the fermentation are determined by suitable agitation-aeration parameters. In addition to conventional nutrient ingredients, the presence of some of the barbituric acid derivatives was found to be essential for rifomycin B production. An attempt was made to explain the mode of action of these compounds.