[Possibility of the early identification of polyene antibiotic producers].

A method for identification of polyenic antibiotics at early stages of their screening was developed using the known fact of high affinity of polygens and steroids. It was found that addition of cholesterol or ergosterol to the nutrient medium in a concentration of 100 gamma/ml eliminated the inhibitory effect of the polyenic antibiotics. Screening of the antibiotic-producing actinomycetes simultaneously on 2 media, i.

[Determination of the biological activity of heliomycin by a method of diffusion in agar].

A biological method for determination of geliomycin activity using agar diffusion is described. A nutrient medium containing Hottinger broth up to 35 mg per cent of amine nitrogen, 1.5 percent of agar-agar, tap water, pH 7.