Evaluation of Metabolites Derived from Lactic Acid Bacteria Isolated from Kimchi

Abstract

Food fermentation facilitates long-term storage and increases the amount of active metabolites produced by lactic acid bacteria (LAB), with consequent beneficial effects for human health. Therefore, the identification of metabolites from fermented foods is important in elucidating the fermentation mechanism and improving the taste, flavor, and amount of active compounds. In this study, we cultured LAB isolated from kimchi and performed liquid chromatography-tandem mass spectrometry with principal-component analysis to analyze the metabolites produced. Kimchi is a popular Korean fermented food with numerous health benefits, and its constituent bacteria have been well-characterized. We have demonstrated that the application of an untargeted metabolomics approach can identify bacteria-specific metabolites. Using this approach, we were able to identify production of the LAB metabolite HICA and showed that HICA catabolism is positively associated with acidic environments, which is the primary physiological phenotype of fermentation. Therefore, elucidation of the specific metabolites produced by these LAB strains used in kimchi fermentation can help to provide further insight into the fermentation process and improve the nutritive value of the product.