The effects of Lactobacilli from raw meat beef on E. coli O157: H7

Background and aims: Lactobacilli are widely distributed in the nature and are present almost everywhere. Because the bacteria are present in various food products, they are used for many years in foods. Studies show lactobacilli has antibacterial properties. The aim of this study was to isolate and identify the species of Lactobacillus from raw beef meat samples and evaluate their antibacterial properties. Methods: In this experimental study, 72 samples of raw beef meat were obtained from slaughterhouses of Sanandaj city. Isolates were evaluated using phenotypic methods (morphology, gram stain and catalase test). In order to identify more precisely, the fermentation of sugars test and molecular polymerase chain reaction (PCR) methods were used. Then, agar well diffusion and spot on plate methods were used to evaluate antibacterial properties of lactobacilli against E. coli O157: H7. Results: A total of 8 species Lactobacilli were isolated from raw beef meat and identified by chemical and molecular methods. The results showed that these 8 species of lactobacilli inhibited E. coli O157: H7 well. These results statistically was considered significant (P<0.05). Conclusion: The results of this study show that raw beef meat has different lactobacilli that can be used as a biological control in foods.