摘要：Lactic acid bacteria (LAB) are safe bacteria which are being used in food production as starter or protective cultures for many years. They produce various antimicrobial compounds including bacteriocins. Bacteriocins, especially the ones produced by LAB, are considered very important because of being natural compounds having the potential to be used in food processing as biopreservatives. In this study, antimicrobial activities of 63 LAB isolated from raw milk and cheese samples were determined. Results of antimicrobial activity assay showed that 6 of the isolates had inhibitory effect on L. monocytogenes, 7 of the isolates had inhibitory effect on S. aureus, and 25 of the isolates had inhibitory effect on both microorganisms in agar spot test, while 7 of the isolates had antimicrobial activity against L. monocytogenes in well diffusion assay. In this research, the 26 numbered isolate, which was determined as the strain producing antimicrobial substance with the highest antimicrobial activity (1600 AU/mL) compared to the others, was identified biochemically as Lactococcus lactis ssp. lactis 1 using API 50CHL (Biomerieux, France).
关键词：Lactic acid bacteria; raw milk; cheese; antimicrobial activity
