Anaerobic plate method for assaying antimicrobial agents in serum

An anaerobic agar plate method was devised for the assay of antimicrobial agents in serum by using a strain of Clostridium bifermentans. The method gave reproducible and accurate in assays of chloramphenicol, clindamycin, and metronidazole alone or in the presence of beta-lactam or aminoglycoside antibiotics.