Article

Discovery of novel biopreservation agents with inhibitory effects on growth of food-borne pathogens and their application to seafood products

Institut National des Sciences et Technologies de la Mer (INSTM), Rue 2 Mars 1934, 2025 Salammbô, Tunis, Tunisia.
Research in Microbiology (Impact Factor: 2.71). 01/2012; 163(1):44-54. DOI: 10.1016/j.resmic.2011.08.005
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ABSTRACT

Selection of protective cultures is relevant in order to biopreserve and improve the functional safety of food products, mainly through inhibition of spoilage and/or pathogenic bacteria. Accordingly, the present study investigated potential applications of lactic acid bacteria (LAB) in the biopreservation of fish and shellfish products. For this purpose, a collection of 84 LAB strains isolated from sea bass (Dicentrarchus labrax) and sea bream (Sparus aurata) was identified and characterized for their inhibitory activities against the most relevant seafood-spoilage and pathogenic bacteria potentially present in commercial products. The bioactive strains belonged to the genus Enterococcus and exhibited inhibition against Carnobacterium sp, Bacillus sp, Listeria monocytogenes, Aeromonas salmonicida, Aeromonas hydrophila and Vibrio anguillarum. Treatment of cell-free extracts of the LAB strains with proteases revealed the proteinaceous nature of the inhibition. Interestingly, the cell-free extracts containing bacteriocins remained 100% active after treatment up to 100 °C for 30 min or 121 °C for 15 min. Molecular analysis led to identification of the bacteriocins investigated, including enterocins A, B, L50 and P. All of these proteins demonstrated remarkable anti-Listeria activity and were found to be heat-resistant small class IIa bacteriocins. The results presented in this work open the way for potential applications of these LAB strains to the biopreservation of minimally-processed seafood products.

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Available from: Monia El Bour, Feb 23, 2014
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    • "(Dicentrarchus labrax) and sea bream (Sparus aurata) showed higher heat resistance since they kept the activity after treatment at 100ºC for 30 min and at 121ºC for 15 min.[48]Bacteriocin DU10 was found to be active at pH 2, 4, 6, 8, 10 and 12. "
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    Full-text · Article · Feb 2015 · Food Microbiology
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    • "Bacteriocin-producing enterococci are widespread in nature. They have been isolated from numerous sources, such as dairy products (Foulqui e Moreno et al. 2006), fermented sausages (Cocolin et al. 2007), fish (Bourouni Chahad et al. 2012), vegetables (Bennik et al. 1998; Zendo et al. 2005) and mammalian gastrointestinal tract (Carina Audisio et al. 2000; Brand~ ao et al. 2010). "
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