Gilvocarcins, new antitumor antibiotics. 1. Taxonomy, fermentation, isolation and biological activities.

Gilvocarcin V and gilvocarcin M, a group of antitumor antibiotics with a novel skeleton, were discovered in culture broths of Actinomycete DO-38. The producing organism, subsequently determined to be a new species and named Streptomyces gilvotanareus (NRRL 11382). Gilvocarcin V and M were isolated by ethyl acetate extraction and chromatography on silica gel. The antibiotics are active against Gram-positive bacteria and experimental tumors such as mouse sarcoma 180 and mouse leukemia P388.