Capacidad antimicrobiana de bacterias ácido lácticas autóctonas aisladas de queso doble crema y quesillo colombiano

Lactic Acid Bacteria (LAB) native to have been reported as an efficient alternative for natural biopreservation, prevention of Foodborne Diseases (ETAS) and improvement production processes of traditional fermented foods. The objective was to evaluate the antimicrobial capacity of native BAL isolated from Double Cream Cheese and Quesillo against the in vitro growth of Salmonella enterica subsp. enterica serovar Typhimurium ATCC 13311 and Listeria monocytogenes ATCC 7644. We studied 32 isolates, previously identified by analysis of 16S rDNA gene sequences and characterized technologically. We tested antimicrobial capacity using an agar spot test. Subsequently, cellfree supernatants were neutralized and filtered to detect their antimicrobial activity using the gel diffusion method by drilling plate. We selected 8 isolates showing inhibitory capacity against the two pathogens microorganisms. Isolated identified as Lactococcus lactis subsp. lactis Q5 presented higher activity, equivalent to 64.000 AU/ml for L. monocytogenes and 4.000 AU/ml for S. typhimurium. It is suggested that BAL from traditional cheeses produce antimicrobial substances Colombian bactericidal potential and can be used in formulating a starter culture with bioprotective effect.