Antibacterial substance produced by Streptococcus faecium under anaerobic culture.

A facultative anaerobe isolated from Korean domestic soil produced an antibacterial substance under strict anaerobic conditions. Based on the morphological and biochemical tests, and cellular fatty acid profiles, the anaerobe was identified as Streptococcus faecium. An antimicrobial compound produced from the S. faecium was identified as 3,7,12-trihydroxy-24-cholanic acid methylester on the basis of its physico-chemical analysis. This substance had potent antibacterial activities against a test organism harboring multiple antibiotic resistance markers, and a variety of pathogenic bacteria. The isolated S. faecium produced lactic acid as well as the antibiotic compound under the anaerobic conditions.