ASSESSMENT OF ANTIBACTERIAL ACTIVITIES OF PEDIOCIN PRODUCED BY PEDIOCOCCUS ACIDILACTICI LAB 5

作者：Mandal Vivekananda; Sen Sukanta K; Mandal Narayan C^*

来源：Journal of Food Safety, 2010, 30(3): 635-651.

DOI：10.1111/j.1745-4565.2010.00230.x

Pediocin NV 5, produced by Pediococcus acidilactici LAB 5, was found to be active against a number of food spoilage and food-related health hazards associated gram-positive bacteria. The partially purified bacteriocin was tested for its mode of action against two sensitive strains - Enterococcus faecalis MB1 and Leuconostoc mesenteroides Ly and was found to be bactericidal at a concentration of 800 AU/mL. Atomic absorption spectroscopy for K+ ions showed that pediocin NV 5 caused pore formation which was comparable to valinomycin on human pathogenic Listeria monocytogenes Microbial Type Culture Collection (MTCC) 657. The scanning electron micrographs showed a great variation in cell morphology like elevated protrusion and barrel shape formation from cocci in treated cells. Pediocin NV 5 treatment (800 AU/mL) did not cause any loss of cellular proteins and DNA from treated cells but treatment at higher activity units (20,000 AU/mL) caused lysis in Listeria monocytogenes MTCC 657 proving its lytic mode of action.
PRACTICAL APPLICATIONS
Postpackage food spoilage of fermented food products of fish, meat, vegetables and dairy products causes a major problem in food preservation. The most predominating spoilage bacteria in both fresh and processed fish, meat, vegetables and dairy products are the species of Bacillus, Campylobacter, Clostridium, Enterobacter, Listeria, Pseudomonas, Salmonella, Serratia, Staphylococcus, Yersinia, etc.; some of them are also reported to have pathogenicity in humans. Among them, Listeria monocytogenes is responsible for listeriosis, a disease with high mortality rate in humans. The use of bacteriocin as food biopreservative is an alternative method for food preservation and a good substitute for the conventionally used chemical preservatives. Results of this study show that high thermotolerant bacteriocins like pediocin NV 5, produced by Pediococcus acidilactici LAB 5, which has bactericidal activity at very low concentration against these organisms, can effectively be considered as a good candidate for food preservation.

• 出版日期2010-8