The inhibitory activity of lactic acid bacteria isolated from fresh cow cheese

Lactic acid bacteria are the constituent part of milk microbialflora that could influence the safety of dairy products due production of organic acids, hydrogen peroxide, carbon dioxide and bacteriocins. Taking this in consideration, the objective of this study was to investigate the composition of lactic acid bacteria population in fresh cow cheeses taken from local markets, as well as their antimicrobial capacity. Lactic acid bacteria counts were determined according to ISO 1524:1998 method, biochemical determination using API 50 CHL system, and inhibitory activity against L. monocytogenes NCTC 1052 7 by agar well diffusion assay. Lactic acid bacteria count in fresh cow cheeses (n=10) ranged from 5.87 to 8.38 log(10) CFU g(-1). Among 52 MRS isolates collected, 61.54 %2were assigned to the Lactococcus lactis subsp. Lactis species, 23.07 %2Lactobacillus helveticus, 11.54 %2Leuconostoc mesenteroides subsp. cremoris and 3.85 %2Leuconostoc mesenteroides subsp. mesenteroides. Antilisterial activity was found in 18 isolates.