Korean kimchi-derived lactic acid bacteria inhibit foodborne pathogenic biofilm growth on seafood and food processing surface materials

Lactic acid bacteria (LAB) with probiotic potential have become highly sought-after by global consumers due to their wide applicability. Here, two LAB strains (J.27 and M.21) were isolated from a traditional Korean fermented vegetable (kimchi) and identified via 16S rRNA gene sequence analyses. Afterward, the two LAB isolates were evaluated for their antibiofilm activity against three foodborne pathogens (Vibrio parahaemolyticus, Pseudomonas aeruginosa, and Escherichia coli) on a seafood model (squid) and food-contact surfaces (rubber and highdensity polyethylene [HDPE] plastic). This study also evaluated the effect of co-culture with LAB isolates on the relative expression of different virulence- and quorum sensing (QS)-associated genes from the three aforementioned pathogens. Our antimicrobial and genetic analyses revealed that the combined LAB isolates exhibited higher planktonic and biofilm cell inhibition on both biotic and abiotic surfaces after co-culture with the three mentioned foodborne pathogens assessed for 24 h. However, the antimicrobial activities of both LAB isolates were higher on abiotic surfaces (HDPE) than on biotic surfaces (squid). Therefore, the results of our in vitro experiments highlighted the potential applicability of both LAB isolates as green bioprotective agents against pathogenic microorganisms in the seafood industry.

Automated summary

This study isolated two LAB strains with probiotic potential from kimchi, and demonstrated their antibiofilm activity against foodborne pathogens on seafood models and food contact surfaces. The combined LAB isolates showed higher inhibition on both planktonic and biofilm cells after co-culture with the pathogens, highlighting their potential as green bioprotective agents in the seafood industry.