Effect of simulated gastric fluid and bile on survival of Vibrio vulnificus and Vibrio vulnificus phage

Bacteria and phages may be exposed to acid conditions in the stomach and to bile in the intestine. Survival of three strains of Vibrio vulnificus and three strains of its phages was examined at 37 degreesC after exposure to s imulated gastric fluid at pH 3 to 4 or to 0, 1, and 2% bile in broth or buf fer. Mean D-values (decimal reduction times) at pH 4 and 3 were 3.3 and 1.3 min for V. vulnificus and 97.8 and 0.7 min far its phages. No V. vulnificu s survivors were found at pH 2.0. There were few survival differences among strains of V. vulnificus or its phages. Numbers of V. vulnificus increased 1 log in tryptic soy broth containing 1 or 2% bile after 3 h. Numbers of V . vulnificus and its phages remained constant in phosphate-buffered saline regardless of bile concentrations up to 3 h. Those V. vulnificus bacteria a nd phages that survive stomach acidity may proliferate in the small intesti ne, since they are resistant to bile.