Complementary Antibacterial Effects of Bacteriocins and Organic Acids as Revealed by Comparative Analysis of spp. from Meat.

and are often predominant in the microbiota of vacuum-packaged (VP) meats after prolonged storage at chiller temperatures, and more so in recent studies. We investigated the antibacterial activities of and ( = 31) from VP meats by phenotypic characterization and genomic analysis. Five strains showed antibacterial activities against Gram-positive bacteria in a spot-lawn assay, with strains having an intergeneric and strains an intrageneric inhibition spectrum. This inhibitory activity is correlated with the production of predicted bacteriocins, including carnobacteriocin B2 and carnolysin for and divergicin A for The supernatants of both species cultured in meat juice medium under anaerobic conditions retarded the growth of most Gram-positive and Gram-negative bacteria in broth assay in a strain-dependent manner. and produced formate and acetate but not lactate under VP meat-relevant conditions. The relative inhibitory activity by strains was significantly correlated ( < 0.05) to the production of both acids. Genomic analysis revealed the presence of genes required for respiration in both species. In addition, two clusters of have an average nucleotide identity below the cutoff value for species delineation and thus should be considered to be two subspecies. In conclusion, both bacteriocins and organic acids are factors contributing significantly to the antibacterial activity of and under VP meat-relevant conditions. A few strains can be explored as protective cultures to extend the shelf life and improve the safety of VP meats. The results of this study demonstrated that both bacteriocins and organic acids are important factors contributing to the antibacterial activities of from vacuum-packaged (VP) meats. This study demonstrated that formate and acetate are the key organic acids produced by and demonstrated their association with the inhibitory activity of carnobacteria under VP meat-relevant storage conditions. The role of lactate, on the other hand, may not be as important as previously believed in the antimicrobial activities of spp. on chilled VP meats. These findings advance our understanding of the physiology of spp. to better explore their biopreservative properties for chilled VP meats.