INHIBITORY ACTIVITY OF LACTIC ACID BACTERIA ISOLATED FROM THAI FERMENTED FOOD AGAINST PANDEMIC STRAINS OF VIBRIO PARAHAEMOLYTICUS

Abstract

ABSTRACT Since 1996, Vibrio parahaemolyticus serotype O3:K6 and its clones have been reported to cause human infections worldwide. In Thailand, infections caused by these pandemic strains are still high. In order to control these infections, an attempt has been made to use probiotic bacteria. In this study, 327 strains of lactic acid bacteria were isolated from 22 types of fermented Thai foods. They were screened for probiotic properties. One isolate designated as PSU‐LAB 71 strongly inhibited the pandemic strains of V. parahaemolyticus and also Vibrio cholerae. PSU‐LAB71 was isolated from naturally fermented pork and was identified as Lactobacillus plantarum. The mechanism of its ability to inhibit V. parahaemolyticus was most likely caused by acid production. PSU‐LAB71 showed high adhesion to an enterocyte‐like Caco‐2 cell line. This study highlighted the possibility of using PSU‐LAB71 as a probiotic strain to control infections by pandemic V. parahaemolyticus.PRACTICAL APPLICATIONSAsian countries use many fermented foods containing lactic acid bacteria. This study describes a method to isolate potential probiotic bacteria from fermented foods that have inhibitory properties against pathogenic Vibrio species, especially pandemic strains of Vibrio parahaemolyticus. This report may initiate other countries that face problems caused by this pathogen to isolate their local lactic acid bacteria that have the potential to act as probiotics to control infections.