Potential beneficial properties of bacteriocin-producing lactic acid bacteria isolated from smoked salmon

Abstract

Aims: To evaluate the probiotic properties of strains isolated from smoked salmon and previously identified as bacteriocin producers. Methods and Results: Strains Lactobacillus curvatus ET06, ET30 and ET31, Lactobacillus fermentum ET35, Lactobacillus delbrueckii ET32, Pediococcus acidilactici ET34 and Enterococcus faecium ET05, ET12 and ET88 survived conditions simulating the gastrointestinal tract (GIT) and produced bacteriocins active against several strains of Listeria monocytogenes, but presented very low activity against other lactic acid bacteria (LAB). Cell‐free supernatants containing bacteriocins, added to 3‐h‐old cultures of L. monocytogenes 603, suppressed growth over 12 h. Auto‐aggregation was strain‐specific, and values ranged from 7·2% for ET35 to 12·1% for ET05. Various degrees of co‐aggregation with L. monocytogenes 603, Lactobacillus sakei ATCC 15521 and Enterococcus faecalis ATCC 19443 were observed. Adherence of the bacteriocinogenic strains to Caco‐2 cells was within the range reported for Lactobacillus rhamnosus GG, a well‐known probiotic. The highest levels of hydrophobicity were recorded for Lact. curvatus (61·9–64·6%), Lact. fermentum (78·9%), Lact. delbrueckii (43·7%) and Ped. acidilactici (51·3%), which are higher than the one recorded for Lact. rhamnosus GG (53·3%). These strains were highly sensitive to several antibiotics and affected by several drugs from different generic groups in a strain‐dependent manner. Conclusions: Smoked salmon is a rich source of probiotic LAB. All strains survived conditions simulating the GIT and produced bacteriocins active against various pathogens. Adherence to Caco‐2 cells was within the range reported for Lact. rhamnosus GG, a well‐known probiotic. In addition, the high hydrophobicity readings recorded define the strains as good probiotics. Significance and Impact of the Study: Smoked salmon contains a number of different probiotic LAB and could be marketed as having a potential beneficial effect.

Probiotic Potential of Autochthone Microbiota from São Jorge and <i>Parmigiano-Reggiano</i> Cheeses

“…This bacterium has been isolated from several cheeses, such as Gouda [40], Lebanese Darfiyeh [41] and Cheddar [25]. This bacterial species probiotic potential has been related to the production of a bacteriocin active against Listeria monocytogenes and E. faecalis [42]; the production of hydrogen peroxide active against E. coli [43]; the survival at conditions of the gastro-intestinal tract [44]; and to its potential immunomodulating effect [45] [46].…”

Probiotic Lactococcus lactis: A Review

“…Moreover, the isolates were resistant to fosfomycin and cefepime (β-lactam group), nalidixic acid, pipemidic acid, and norfloxacin (quinolones), amikacin, kanamycin, and neomycin (aminoglycosides), sulphadiazine (sulphonamides), colistin, and polymixin (polypeptide), teicoplanin (glycopeptides), and nystatin and amphotericin B of the antifungal group of antibiotics. Liasi et al, (2009) The interaction between antibiotics and probiotic bacteria in the gastrointestinal tract (GIT) depends upon their amount of active compounds (Todorov et al, 2011). Thus, if a particular antibiotic is inhibitory to probiotic L. lactis, the viability of probiotic bacteria would be affected in GIT, hence, determination of minimal inhibitory concentration (MIC) values plays an important role for proper evaluation of these interactions.…”

Molecular Characterization of Bacteriocinogenic, Antifungal and Probiotic Lactic Acid Bacteria Isolated from Chicken Gastrointestinal Tract

“…at 600 nm is 0.2) at 37˚C. Optical density readings were recorded at 600 nm every hour for 8 h and after 24 h, while cultures grown in MRS broth pH 6.5 served as the control [24]. The experiment was performed in triplicates.…”