[Macrotetrolide antibiotics from mycelia of Streptomyces chrysomallus]

White crystalline antibiotically active substances identified as macrotetrolides were isolated from the mycelium of four actinomycetous strains, i.e. S. chrysomallus var. I, S. chrysomallus var. III, S. chrysomallus var. carotenoides and S. chrysomallus var. macrotetrolidi. The component composition of the macrotetrolide antibiotics of all four strains was identical. It was characterized by predominance of nonactin, a lower homologue. The composition ratio was the following: 69-79 per cent of nonactin, 19-29 per cent of monactin, 1-3 per cent of dinactin and the traces of trinactin and tetranactin. The strains differed in the intensity of production of the macrotetrolides and the ability to synthesize other biologically active substances.