Not Everything is a Question of Reputation: Safety of Bacteriocinogenic Lab Isolated from Smoked Salmon

Abstract

Total DNA extracted from bacteriocinogenic and potential probiotic lactic acid bacteria (LAB) (Lactobacillus curvatus ET06, ET30 and ET31, Lactobacillus fermentum ET35, Lactobacillus delbrueckii ET32, Pediococcus acidilactici ET34 and Enterococcus faecium ET05, ET12 and ET88), have been screened for presence of more than 50 genes related to production of biogenic amines (histidine decarboxylase, tyrosine decarboxylase and ornithine decarboxylase), virulence factors (sex pheromones, gelatinase, cytolisin, hyaluronidase, aggregation substance, enterococcal surface protein, endocarditis antigen, adhesion of collagen, integration factors) and antibiotic resistance (vancomycin, tetracycline, erythromycin, gentamicin, chloramphenicol, bacitracin). Tested strains presented low frequencies of presence for virulence genes. Only few genes were detected in some strains, indicating their safety for application in fermented food products. Besides all beneficial properties studied for various LAB, most considered as GRAS, a special attention need to be addressed on the possible presence of virulence factors, production of biogenic amines and antibiotic resistance. Results from appropriate biochemical tests and detected main genes associated to virulence factors and antibiotic resistance in LAB strains, could be considered as potential hazard of application of this organisms in food products. Moreover, additional in vitro and in vivo experiments must be designed in the system simulating GIT conditions in order to investigate deeper the possible expression of the present virulence genes.