In vitro tests of suitability of bacteriocin-producing lactic acid bacteria, as potential biopreservation cultures in vacuum-packaged cold-smoked salmon

Abstract

The objectives of this study were to ascertain the in vitro potential of nine bacteriocin-producing lactic acid bacteria (LAB) strains, isolated from vacuum-packaged cold-smoked salmon (CSS), for possible use as biopreservative cultures against Listeria monocytogenes. The antilisterial activity of cultures' supernatants was assessed at 0.5%, 3.0% and 5.0% w/v of salt, at 5°C, 10°C and 25°C both in aerobic and anaerobic atmospheres, simulating the conditions pertaining in vacuum-packaged CSS. The kinetics of growth, bacteriocin biosynthesis, the minimum inhibitory concentrations (MICs) of ten antibiotics, histamine and tyramine production of LAB strains, were determined jointly with the haemolytic activity for the enterococci. Only five strains were able to secrete active bacteriocins into the culture medium, at high salt concentrations and low temperatures, both in aerobic and anaerobic atmospheres. Enterococci showed neither haemolyt ic activity nor vancomycin resistance. The production of histamine was not observed for any of the bacteriocin-producing strains.

Selection of Lactobacillus Species from Intestinal Microbiota of Fish for Their Potential Use as Biopreservatives

“…In kinetic studies, both crude bacteriocins were continuously produced during logarithmic phase followed by optimal production during stationary growth phase, suggesting that these peptides may be secondary metabolites. Similar results were reported for some bacteriocins produced by some LAB isolates [5,64,65] and is contrary for other Lactobacillus species bacteriocins [1,16,25,55,60,66]. Bacteriocin H5 showed a decrease in activity towards the end of stationary growth may be due to proteolytic degration, protein aggregation, and feedback regulation as has been observed for Lactacin ST13BR, Lactacin B, Helveticin J and Enterocin1146 [53,55,67].…”

Lactic Acid Bacteria and Their Bacteriocins: A Promising Approach to Seafood Biopreservation

“…The association of L. casei T3 and L. plantarum PE2 was the most effective, probably due to a competition mechanism against the pathogen. In their study Tomé et al [144] have also selected a strain of Enterococcus faecium among five bacteriocinogenic LAB strains for its ability to induce a decrease of the population of L. innocua inoculated in CSS. However in these studies the inhibition activities were not confirmed on L. monocytogenes.…”

Antimicrobial susceptibility of Enterococcus spp. isolated from freshwater fish and personnel and equipment of fish markets in northern Greece

“…Enterococci are frequently isolated from various foods of animal origin (Chingwaru et al, 2003;Çitak et al, 2004;Jaffrès et al, 2009;Sergelidis et al, 2010). They have also been isolated from aquatic habitats, fish and seafood (rice et al, 1995;Wilson and Mcafee, 2002;Petersen and Dalsgaard, 2003;Quigg et al, 2009;Al bulushi et al, 2010;Valenzuela et al, 2010).The organisms are also part of the spoilage flora of processed fish products (Dalgaard et al, 2003;Mejlholm et al, 2008;Tomé et al, 2008;Jaffrès et al, 2009).…”

“…Enterococci exhibit interesting technological and probiotic properties and their beneficial role in food fermentations, ripening and biopreservation has been recognised (Giraffa, 2003;Hugas et al, 2003;Tomé et al, 2008). Despite their beneficial properties, they are considered to be faecal contamination indicators and responsible for food spoilage (Franz et al, 1999;Dalgaard et al, 2003;Jaffrès et al, 2009).…”