Characterization of Lacticaseibacillus rhamnosus, Levilactobacillus brevis and Lactiplantibacillus plantarum Metabolites and Evaluation of Their Antimicrobial Activity against Food Pathogens

Lactic acid bacteria (LAB) play an important role as natural food preservatives. However, the characterization of the variety of their metabolites is limited. The objective of this study was to determine the production of specific metabolites of Lacticaseibacillus rhamnosus, Levilactobacillus brevis and Lactiplantibacillus plantarum by an optimized liquid chromatography with an ultraviolet/diode detection (HPLC-UV/DAD) method and to investigate their potential antimicrobial activity against specific food pathogens. Based on the results of this study, the main metabolites detected in Levilactobacillus brevis were 103.4 mu g mL(-1) DL-p-Hydroxyphenyllactic acid (OH-PLA) and 2.59 mu g mL(-1) vanillic acid, while 216.2 mu g mL(-1) OH-PLA, 19.0 mu g mL(-1) salicylic acid, 3.7 mu g mL(-1) vanillic acid, 6.9 mu g mL(-1) ferulic acid, 4.2 mu g mL(-1) benzoic acid and 1.4 mu g mL(-1) 4-Hydrocinnamic acid were identified in the Lactiplantibacillus plantarum strain and 147.6 mu g mL(-1) OH-PLA and 4.9 mu g mL(-1) ferulic acid were identified in Lacticaseibacillus rhamnosus. This study provides alternative approaches for the molecules involved in the antimicrobial activity of food microorganism fermentation. These molecules may be used as antimicrobial ingredients in the food industry instead of conventional chemical preservatives.