Bile acid inhibition of Clostridium botulinum.

Bile acids and their glycine and taurine conjugates were tested in vitro for inhibition of Clostridium botulinum types A and B. Cholic acid inhibited most strains at 2 mg/ml, whereas chenodeoxycholic acid inhibited all strains at 0.4 mg/ml. Deoxycholic acid inhibited one strain at 0.08 mg/ml and other strains at 0.4 and 2 mg/ml. Lithocholic acid inhibited all strains at 0.016 mg/ml. Glycine conjugates also showed considerable inhibition of some strains, whereas taurine conjugates were inactive.