Selection of bacteriocin producer strains of lactic acid bacteria from a dairy environment
Lasagno, M.; Beoleito, V.; Sesma, F.; Raya, R.; Font de Valdez, G.; Eraso, A.
New Microbiologica 25(1): 37-44
2002
ISSN/ISBN: 1121-7138 PMID: 11837389 Document Number: 540958
Two strains showing bacteriocin production were selected from a total of 206 lactic acid bacteria isolated from samples of milk, milk serum, whey and home-made cheeses in Southern Cordoba, Argentina. This property was detected by means of well diffusion assays. The strains were identified as Enterococcus hirae and Enterococcus durans. The protein nature of those substances was proved by showing their sensitivity to type IV and XXV proteases, papaine, trypsin, pepsin and K proteinase. The bacteriocins inhibited the growth of Listeria monocytogenes, Bacillus cereus, Clostridium perfringens and two strains of Staphylococcus aureus, an A-enterotoxin and a B-enterotoxin producers. All of these bacteria are common pathogens usually associated with food borne diseases (ETA). These lactic acid bacteria or their bacteriocins could be suitable candidates for food preservation and specially useful in the our regional dairy industry.