Identification and Characterization of a Bacteriocin-Like Substance, Produced by Leuconostoc mesenteroides, as a Bio-Preservative Against Listeria monocytogenes

By conducting a systemic screening from Chinese traditional Tofu, a bacteriocin producer with broad antimicrobial spectrum was found. The producer was identified by 16S rDNA sequencing, and it was identified as Leuconostoc mesenteroides. The producer possessed typical bacteriocin traits, such as be heat-stable and proteinase-labile. Its inhibition spectrum contained many distantly related genera of Firmicutes, comprising most lactic acid bacteria (LAB) as well as problematic species of Bacillus, Listeria and Staphylococcus. In addition, the bacteriocin producer showed significantly inhibition effects on controlling Listeria monocytogenes in milk. Taken together, the results indicate that this is a novel and potent bacteriocin from Leu.mesenteroides and that its very broad inhibition spectrum can be use in food preservation as well as in infection treatments caused by Gram-positive pathogens.