• 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.

• 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.