YS-822A, a new polyene macrolide antibiotic. I. Production, isolation, characterization and biological properties

A new polyene macrolide antibiotic, YS-822A was isolated from the culture filtrate of a mutant strain H-8 of Streptoverticillium eurocidicum var. asterocidicus S-822. Whereas the original S-822 strain produced not only YS-822 substances but also teleocidin as by-product which is well-known as a strong carcinogenic promoter, the mutagenized H-8 strain produced the antibiotic with only a trace amount of teleocidin. Chemical and biological characterizations of the antibiotic revealed that YS-822A (molecular formula: C37H59NO14) is a new polyene macrolide with a wide antifungal spectrum and a low acute toxicity.