Reduction in Biogenic Amine Content in Baechu (Napa Cabbage) Kimchi by Biogenic Amine-Degrading Lactic Acid Bacteria

This study was performed to mine biogenic amine (BA)-degrading lactic acid bacteria (LAB) from kimchi and to investigate the effects of the LAB strains on BA reduction in Baechu kimchi fermentation. Among 1448 LAB strains isolated from various kimchi varieties, five strains capable of considerably degrading histamine and/or tyramine were selected through in vitro tests and identified as Levilactobacillus brevis PK08, Lactiplantibacillus pentosus PK05, Leuconostoc mesenteroides YM20, L. plantarum KD15, and Latilactobacillus sakei YM21. The selected strains were used to ferment five groups of Baechu kimchi, respectively. The LB group inoculated with L. brevis PK08 showed the highest reduction in tyramine content, 66.65% and 81.89%, compared to the control group and the positive control group, respectively. Other BA content was also considerably reduced, by 3.76-89.26% (five BAs) and 7.87-23.27% (four BAs), compared to the two control groups, respectively. The other inoculated groups showed similar or less BA reduction than the LB group. Meanwhile, a multicopper oxidase gene was detected in L. brevis PK08 when pursuing the BA degradation mechanism. Consequently, L. brevis PK08 could be applied to kimchi fermentation as a starter or protective culture to improve the BA-related safety of kimchi where prolific tyramine-producing LAB strains are present.

Automated summary

This study successfully identified lactic acid bacteria capable of degrading biogenic amines from kimchi and demonstrated their effectiveness in reducing amine content during Baechu kimchi fermentation. Among the strains, Levilactobacillus brevis PK08 showed the highest reduction in tyramine content, potentially improving the safety of kimchi fermentation.