Bacteriocin Producing Lactobacilli Strains as a Biological Strategy to Control Listerial Growth

GARCÍA MARÍA JOSÉ; RUIZ, FRANCISCO; ASURMENDI, PAULA; PASCUAL, LILIANA; BARBERIS, LUCILA

International Journal of Microbiology & Advanced Immunology

SciDoc Publishers

Año: 2015 vol. 3 p. 60 - 64

2329-9967

Listeria monocytogenes causes listeriosis in humans and animals, and is predominantly transmitted by ingestion of contaminatedfood. Its severity and high mortality rate make listeriosis a relevant foodborne disease. Currently, biological strategies usingprobiotic lactobacilli to prevent and control infectious diseases are being globally investigated. The biocontrol exerted bycertain Lactobacillus spp. is mainly due to the production of a variety of antimicrobial substances. The aims of this work were(1) to investigate the presence of Listeria spp. in raw cow milk and (2) to determine the inhibitory activity of bacteriocin-likeinhibitory substances (BLIS-es) produced by Lactobacillus fermentum L23 and Lactobacillus rhamnosus L60 on L. monocytogenesand other listerial species isolated from food and clinical samples. The presence of Listeria spp. in raw milk was evaluated in814 samples from 238 cows. The listerial prevalence in cattle was 0.84% and the isolates were identified as L. innocua (LI1)and L. welshimeri (LW1). A total of 29 listerial strains were used as indicator microorganisms to evaluate the antimicrobialactivity of BLIS-es L23 and L60. Bioactive metabolites produced by these lactobacilli strains were able to inhibit the listerialgrowth. This biological activity was mainly attributed to the BLIS-es L23 and L60 which, even at low concentration, wereactive on 100% of listerial strains. This study reveals a strong potential for the biotechnological use of these bacteriocinproducing lactobacilli as a biostrategy against Listeria spp.