Bacteriocin Harvested from the Synbiotic Culture of Selected Lactic Acid Bacteria with Various Vegetables, Cereals, Fruits, Medicinal and Tuber Plants: Inhibition of Vibrio parahaemolyticus

Abstract The present study was to investigate and identify the antimicrobial lactic acid bacteria against some gastrointestinal pathogens, to compare the activity between their synbiotic culture and bacteria culture alone, and to characterize the bacteriocins produced by the synbiotic culture of these isolates. Among 600 isolates of selected lactic acid bacteria, three isolates of Lactocaseibacillus paracasei subsp. paracasei, two of Latilactobacillus curvatus subsp. curvatus, and one of Lactiplantibacillus plantarum exhibited the antibacterial activities against four standard reference bacteria, and twelve clinical strains of food-poisoning bacteria especially Vibrio parahaemolyticus. The synbiotic culture of L. paracasei 9/5, L. curvatus 87/6 and L. plantarum 89/4 which are cultured with sweet corn, grand red bean, papaya, star fruit, nashi pear, and black ginger exhibited significant inhibitions to V. parahaemolyticus. Bacteriocin which was harvested from the synbiotic culture of L. curvatus 87/6 and nashi pear demonstrated the strongest activity to the tested bacteria. After partial purification, ultrafiltration, and ion exchange column chromatography, this bacteriocin was anionic with 40-80 kDa and pI at 4-5. Its antimicrobial activities significantly decreased at pH > 8.0, with trypsin and pepsin digestions as well as after heating at > 100°C. Analyzed with SDS-PAGE, the suspected bacteriocin band was detected in the increased intensity, lower intensity, and was not detected after harvested from the synbiotic culture, the bacterial culture alone, and only plant powder extract, respectively. It was concluded that the synbiotic culture of L. curvatus with some prebiotics could induce potent antimicrobial bacteriocin production. Keywords: Lactic acid bacteria, Prebiotics, Synbiotic, Bacteriocin, Vibrio parahaemolyticus