A new polyene with antimycotic activity produced by a streptomycete from the rhizosphere of an indoor plant.
From the rhizosphere of a potted Sanseviera trifasciata, a Streptomyces griseus strain with a broad antifungal activity was isolated; in the soil of this plant, a sole hyphomycete, Aspergillus niger, was found in pure culture at 37 degrees C. This streptomycete produced a polyene, belonging to the pentaene group. It was found to inhibit, in vitro, the growth of all the 123 strains tested; the strains belonging to the genera Aspergillus, Cryptococcus, Candida, Trichophyton, Epidermophyton, Microsporum, Penicillium and Mucor. An antimycotic activity of this substance was also found to be present after i.v. administration to white mice infected with Cr. neoformans. Toxicological tests will have to show if this polyene could be considered as a candidate antimycotic drug. The soil of potted indoor plants is discussed as a possible habitat for streptomycetes with defined antifungal activities.