CERELA   05438
CENTRO DE REFERENCIA PARA LACTOBACILOS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Safety and in vitro study of beneficial properties of lactic acid bacteria isolated from Portuguese fermented meat products
Autor/es:
TODOROV, S.D.; FRANCO, B. D. G. M.; LEBLANC, J.G.; WIID, I.J.
Lugar:
Egmond aan Zee
Reunión:
Simposio; 11th International Symposium on Lactic Acid Bacteria; 2014
Resumen:
Many lactic acid bacteria (LAB) produce bacteriocins with rather broad spectra of inhibition and could offer potential applications in food preservation. The bacteriocin production by starter cultures may have an advantage for these strains in competitive interactions with the pathogenic bacteria from the food matrix. The objective of this study was to determine the safety of beneficial strains Lactobacillus pantarum ST202Ch and ST216Ch, Enterococcus faecium ST211Ch, Lactobacillus sakei ST22Ch, ST153Ch and ST154Ch previously isolated from fermented meat products and characterized as bacteriocin producers. Auto-aggregation is strain-specific, and values 28.97%, 27.86% and 28.56% were recorded for Lactobacillus sakei ST22Ch, ST153Ch and ST154Ch, 16.95% and 14.58% for Lactobacillus pantarum ST202Ch and ST216Ch and 12.77% for Enterococcus faecium ST211Ch. Various degrees of co-aggregation between 28.85% and 44.76% with Listeria monocytogenes 211, Listeria monocytogenes 409 and from 23.60% to 34.96% with Enterococcus faecium ATCC 19553 were observed. According to the results of the diffusion method, studied strains demonstrated susceptibility to penicillin G, ampicillin, amoxicillin, amoxicillin/clavulonic acid, imipenem, linezolid and tetracycline. In addition susceptibility of these 6 strains to various non-antibiotic commercial medicaments was examined. Production of β-galactosidase by L. sakei ST22Ch, ST153Ch and ST154Ch, Lactobacillus plantarum ST202Ch and ST216Ch and Enterococcus faecium ST211Ch was confirmed by employing sterile filter paper disks impregnated with o-nitrophenyl-b-D-galactopyranose. A statistically significant (p<0.001) repression of Mycobacterium tuberculosus growth by bacteriocins produced by Lactobacillus pantarum ST202Ch (38.3% inhibition), Lactobacillus pantarum ST216Ch (48.6% inhibition), Enterococcus faecium ST211Ch (21.7% inhibition), Lactobacillus sakei ST153Ch (16.2% inhibition) and Lactobacillus sakei ST154Ch (16.1% inhibition) was observed. The tested six strains showed a low virulence gene profile as was determined by PCR.