Evaluation of bacteriocin-producing lactic acid bacteria strains isolated from “nem chua Thu Duc”

Abstract

This study aimed to select some lactic acid bacteria (LAB) strains to produce bacteriocin isolated from two different local brand names of nem chua Thu Duc, a Vietnamese traditional fermented meat product. Eight different LAB strains were isolated from products. However, only Pediococcus pentosaceus isolated from 72-h fermented “Ba Chin” products and Weissella paramesenteroides isolated from 120-h fermented “Diem” products were selectively screened for their bacteriocin production. The antimicrobial activity was detected by the agar diffusion method against Escherichia coli ATCC 25922, Salmonella enterica serovar Typhimurium ATCC 13076, Staphylococcus aureus ATCC 6538, and Bacillus cereus ATCC 25924 used as target strains. Bacteriocin of Pediococcus pentosaceus strain showed a high antibacterial ability with a sterile ring diameter that produces an average of 12.20 - 16.07 mm. Bacteriocin of Weissella paramesenteroides strain only showed inhibitory activity on the growth of indicator microorganisms with an average inhibitory ring diameter of 9.75 - 15.27 mm. In conclusion, it seems like both bacteriocin-producing P. pentosaceus and W. paramesenteroides give potential applications as a starter culture, bio-preservation and bio-safety control in fermented meat as well as other kinds of fermented foods.