The in-vitro activity of bicozamycin against anaerobic bacteria of clinical interest.

The in-vitro activity of bicozamycin (bicyclomycin, CGP 3543E; FR 1881), an oral antidiarrhoeal agent, was assessed against 389 clinical isolates and reference strains of anaerobic bacteria. The compound inhibited the majority of Gram-negative anaerobes at concentrations of 256 mg/l or less, but all of the test anaerobic cocci and 40 out of 43 strains of clostridia were resistant to this concentration, with MIC values usually in excess of 1024 mg/l. MBC values for bicozamycin against strains of Bacteroides fragilis were generally greatly in excess of MIC values.