• Food Science and Industry
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• v.44 no.3
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• pp.50-55
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• 2011

• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.6
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• pp.600-605
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• 2012

In this study, we investigated the mechanism of inhibition of pathogenic bacteria by Pediococcus pentosaceus strain SH-10 isolated from hard Clam Meretrix meretrix sikhae. When P. pentosaceus SH-10 was co-cultured in MRS broth with pathogenic bacteria, including Bacillus cereus, Listeria monocytogenes, Salmonella choleraesuis and Staphyloccus aureus, no viable pathogenic cells were detected after 18 h of incubation. However, pediocin or a pediocin-like bacteriocin was not detected in cultures of P. pentosaceus SH-10 by the agar diffusion method. Organic acids were produced in MRS broth in proportion to the incubation time of P. pentosaceus SH-10. These results indicate that P. pentosaceus SH-10 inhibited the growth of pathogenic bacteria by lowering the pH of the growth medium through the production of organic acids, including sodium lactate, sodium acetate, and sodium citrate.

• Proceedings of the Microbiological Society of Korea Conference
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• 2005.05a
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• pp.215.4-215
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• 2005

• Journal of Microbiology and Biotechnology
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• v.28 no.4
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• pp.510-519
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• 2018

Synbiotics are a combination of probiotics and prebiotics, which lead to synergistic benefits in host welfare. Probiotics have been used as an alternative to antibiotics. Among the probiotics, Pediococcus acidilactici (PA) has shown excellent antimicrobial activity against Salmonella Gallinarum (SG) as a major poultry pathogen and has improved the production performances of animals. Inulin is widely used as a prebiotic for the improvement of animal health and growth. The main aim of this study was to investigate the antimicrobial activity of inulin nanoparticle (IN)-internalized PA encapsulated into alginate/chitosan/alginate (ACA) microcapsules (MCs) for future in vivo application. The prepared phthalyl INs (PINs) were characterized by DLS and FE-SEM. The contents of phthal groups in the PINs were estimated by $^1H-NMR$ measurement as 25.1 mol.-%. The sizes of the PINs measured by DLS were approximately 203 nm. Internalization into PA was confirmed by confocal microscopy and flow cytometry. The antimicrobial activity of PIN-internalized probiotics encapsulated into ACA MCs was measured by coculture antimicrobial assays on SG. PIN-internalized probiotics had a higher antimicrobial ability than that of ACA MCs loaded with PA/inulin or PA. Interestingly, when PINs were treated with PA and encapsulated into ACA MCs, as a natural antimicrobial peptide, pediocin was produced much more in the culture medium compared with other groups with inulin-loaded ACA MCs and PA encapsulated into ACA MCs.

• Food Science and Biotechnology
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• v.16 no.5
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• pp.675-690
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• 2007

Bacteriocins in Gram-positive bacteria have attracted much attention because many have a strong antimicrobial activity also against bacteria outside the genera of the producers. Lantibiotics and the pediocin-like bactericins have attracted most attention since they kill a broad spectrum of Gram-positive bacteria including important pathogens. But many other promising Gram-positive bacteriocins have been thoroughly characterized. Recent studies have shown that bacteriocins may playa role in the intestinal flora to protect us against the food-borne pathogens. Bacterial genome sequencing has demonstrated that there may be an arsenal of such compounds and we are only seeing the top of the iceberg. The present review gives a short outlook of the field of bacteriocins with focus on lactic acid bacteria and includes recent findings.

• Microbiology and Biotechnology Letters
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• v.46 no.3
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• pp.288-299
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• 2018

Food bio preservation is of major interest in the food industry. Many types of antimicrobial compounds can be produced by lactic acid bacteria (LAB), including bacteriocins. Bacteriocins increase the shelf-life of food by decreasing some food-borne diseases. In this study, a multi-coding sequence of bacteriocin genes was used for primer design to produce bacteriocin genes in Enterococcus faecium AH2 strain and Pediococcus pentosaceus AH1. Multi-coding sequences were aligned to detect conserved sequences in the bacteriocin gene. Eight genes encoding proteins involved in bacteriocin production were isolated and sequenced, including six from E. faecium AH2 (entA, entI, entF, entR, orfA2, orfA3) and two from P. pentoceseus AH1 (papA, pedB), and all gene sequences were deposited in the Gen Bank database under accession numbers LC064146-LC064151, LC101300, and LC101789, respectively. P. pentosaceus AH1 and E. faecium AH2 strains displayed bacteriocin activities of $2610AU\;mL^{-1}$ and $690AU\;mL^{-1}$ and inhibition zones of 26 mm and 19 mm, respectively. Overexpression of entA in E. faecium AH2 increased the bacteriocin and antimicrobial activities.