title: Effect of bile and desoxycholate on gram-negative anaerobic bacteria.
abstract: The bile tests for characterizing gram-negative anaerobic bacilli were reevaluated in prereduced anaerobically sterilized peptone-yeast-glucose broth, in thioglycollate broth, and on blood agar plates. Blood agar plates were unsatisfactory. The combination of 20% bile with 0.1% desoxycholate inhibited Fusobacterium, Bacteroides melaninogenicus, and B. oralis and sometimes Sphaerophorus necrophorus, but not B. fragilis or other Sphaerophorus species studied. Ten per cent bile with 0.05% desoxycholate was less satisfactory. There was no significant difference between fresh and commercial powdered bile. Desoxycholate (0.1% in thioglycollate broth) inhibited B. fragilis, Fusobacterium, B. melaninogenicus, B. oralis, and S. necrophorus, but not S. varius or S. mortiferus/S. ridiculosus. The bile and desoxycholate tests are simple to perform and helpful for characterization and classification of gram-negative anaerobic bacilli.
mesh_terms: D000818:Animals; D001431:Bacteriological Techniques; D001439:Bacteroides / Q000187:drug effects* / Q000254:growth & development; D001646:Bile; D001647:Bile Acids and Salts / Q000494:pharmacology*; D002245:Carbon Dioxide; D002417:Cattle; D005673:Fusobacterium / Q000187:drug effects* / Q000254:growth & development; D013045:Species Specificity
chemical_list: D001647:Bile Acids and Salts; D002245:Carbon Dioxide