Screening of Bacteriocin-producing Lactic Acid Bacteria and the Characteristics of Bacteriocin

[Objective] To study bacteriocin characteristics of lactic acid bacteria isolated from koumiss. [Method] Nineteen strains of lactic acid bacteria were isolated from koumiss in Inner Mongolia region. Through the Oxford cup double agar diffusion method,after eliminating the interference of organic acids and hydrogen peroxidea. Screening one strain of bacteriocin producing lactic acid bacteria strain XMD6 by the protease sensitivity test. [Result]The lactic acid bacteria was identified as E. durans by morphological,physiological and biochemical method and 16 S rRNA gene sequence homology analysis. The bacteriocin of strain XMD6 heat-stable at 80 ℃,and p H in the range of 2- 7 have antibacterial activity. The inhibitory spectrum test showed that it can inhibit the gram positive and gram negative pathogenic bacteria and spoilage bacteria in food,has a wider antibacterial spectrum. [Conclusion] The study can provide theoretical basis for development and utilization of new type bacteriocin preservative.