Enterocin is a new antibiotic isolated from cultures of two strains of Streptomyces, which were given the names Streptomyces candidus var. enterostaticus WS-8096 and variant M-127 of Streptomyces viridochromogenes. Its elementary analysis and mass spectroscopic measurement suggest the molecular formula is C22H20010. The ultraviolet absorption gave two maximal peaks at 250 nm and 283 nm in methanol. Enterocin has static activities against gram-positive and gram-negative bacteria and no activity against fungi and yeast.