| Summary: | Biopreservation is a food preservation technology using microorganisms and/or their inherent antimicrobial metabolites to inhibit undesirable microorganisms. The aim of the present study was to explore the diversity and antimicrobial activity of lactic acid bacteria (LAB) strains (<i>n</i> = 99) isolated from ready-to-eat (RTE) seafood (cold-smoked salmon (CSS), gravlax, and sushi) towards two strains of <i>Listeria monocytogenes</i> (CCUG 15527, F11), <i>Listeria innocua</i> (CCUG 15531) and <i>Escherichia coli</i> (CCUG 38079). The LAB strains were assigned to five different genera (<i>Carnobacterium</i> spp., <i>Lactobacillus</i> spp., <i>Leuconostoc</i> spp., <i>Weissella</i> spp., and <i>Enterococcus </i>sp.) by sequencing a 1150 bp stretch of the 16S rRNA gene. A significant association between the seafood source and the distribution of LAB genera was found (<i>p</i> < 0.001), of which <i>Leuconostoc</i> spp. were most prevalent in sushi and <i>Carnobacterium</i> sp. and <i>Lactobacillus</i> sp. were most frequently isolated from CSS and gravlax. Antimicrobial activity among the LAB was significantly affected by LAB genera (<i>F</i>= 117.91, <i>p</i> < 0.001, one-way ANOVA), product of origin (<i>F</i> = 3.47, <i>p</i> < 0.05), and target (<i>F</i> = 4.64, <i>p</i> = 0.003). LAB isolated from sushi demonstrated a significantly higher antimicrobial effect than LAB from CSS and gravlax (<i>p</i> < 0.05). In general, a significantly higher antimicrobial activity was found towards <i>Listeria</i> spp. than <i>E. coli </i>(<i>p</i> < 0.05). However, <i>Leuconostoc</i> spp. demonstrated similar antimicrobial effects towards <i>E. coli </i>and <i>Listeria</i> spp., except for <i>L. monocytogenes </i>F11 being more sensitive (<i>p</i> < 0.05). This study suggested that seafood-derived LAB strains could be selected for technological application in RTE seafood systems.
|
|---|
