Listeria monocytogenes biofilm inhibition and/or displacement by bacteriocinogenic Lactobacillus sakei CRL1862

VIGNOLO, GRACIELA; PÉREZ IBARRECHE, MARIANA; CASTELLANO, PATRICIA

Egmond aan Zee

Simposio; 11th International Symposium on Lactic Acid Bacteria. Health, Sustainability, Diversity, and Application; 2014

FEMS

Biofilms are complex microbial communities widespread in nature. Since biofilms are very difficult to eradicate, the ability of bacteria to form biofilms poses a major problem in industrial and medical settings, being a persistent source of contamination and/or infection. Recently, major advances have been made in the prevention and control of pathogens biofilm by lactic acid bacteria. Therefore, the objective of this study was to investigate the ability of Lactobacillus sakei CRL1862 and/or its bacteriocins to compete, exclude or displace L. monocytogenes FBUNT during biofilm formation on stainless steel (SS) and polytetrafluoretylene (PTFE) surfaces at 10 ºC. Assayed inhibitory strategies involved (i) displacement (L. sakei CRL1862 planktonic cells, its supernatant and partially purified bacteriocin on pathogen biofilm), (ii) exclusion (L. monocytogens FBUNT planktonic cells on L. sakei CRL1862 biofilm) and (iii) competition (biofilm formed by L. sakei CRL1862 + pathogen planktonic cells). L. monocytogenes biofilm displacement showed partially purified bacteriocin addition as the most effective antimicrobial treatment compared with supernatant and planktonic bacteriocinogenic cells, reducing pathogen biofilm in 3.5 log on SS and PTFE surfaces. Biofilm formation by L. monocytogenes in the exclusion assay was prevented by L. sakei CRL1862 biofilm showing 4.0 and 2.7-log reductions on PTFE and SS, respectively. However, the greatest inhibition of L. monocytogenes biofilm cells was observed during competition assay; pathogen cells in the biofilm were significantly reduced by 5.5 and 4.5 log on PTFE and SS, respectively. Moreover, a greater inhibition of L. monocytogenes biofilm on PTFE than on SS was found. These results shows the effectiveness of bacteriocinogenic L. sakei CRL1862 for the prevention and control of L. monocytogenes on abiotic surfaces