Abstract:In this study, a systemic screening for lactic acid bacteria with antimicrobial activity, from fermented Tofu against common food-borne pathogens was conducted. Four out of sixty-four isolates with antimicrobial activity against all the indicators (Staphylococcus aureus, Listeria monocytogenes and Bacillus cereus) were obtained, and they were identified as Lactococcus lactis(named after DH2002 and DH2004), Enterococcus faecalis(named after DH2001) and Leuconostoc mesenteroides (named after DH2003) based on the results of 16S rDNA sequence and physiological and biochemical analysis. The bacteriocins produced by those four lactic acid bacteria had the typical bacteriocin traits, such as being of heat-stable and proteinase nature. Meanwhile, their inhibition spectrum contained many distantly related genera of Firmicutes, comprising most lactic acid bacteria as well as problematic species of Bacillus, Listeria, and Staphylococcus. However, no activity against Gram-negative bacteria was found. In addition, the model of actions of those bacteriocin producers was determined by using the partial purified bacteriocin against S. aureus. The results showed that DH2001 and DH2002 had bactericide activity, while DH2003 had bacteriostatic activity against S. aureus.