Evaluation of Quorum Quenching Activity of Lactic Acid Bacteria Isolated from Fermented Foods via Chromobacterium violaceum Biosensor

Quorum sensing (QS) is a bacterial communication system regulating virulence, biofilm formation, and antimicrobial resistance via autoinducer signaling molecules. Disrupting QS, known as quorum quenching (QQ), represents a promising strategy for controlling bacterial pathogenicity without promoting antibiotic resistance. This study aimed to screen lactic acid bacteria (LAB) isolated from diverse fermented foods for QS inhibition (QSI) activity using Chromobacterium violaceum ATCC 12472 as a biosensor. Among 208 LAB isolates, only 11 strains inhibited violacein production, indicative of significant QSI activity. Further assessment with cell-free culture supernatants revealed that isolate WPL10 demonstrated the highest violacein inhibition at 18.4%. In contrast, 28 isolates exhibited weak activity, and the remaining 169 showed no inhibitory effect. The most active isolate, identified as Lactiplantibacillus plantarum WPL10 via Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometer (MALDI-TOF MS), showed promising QQ potential likely mediated by metabolic products or enzymatic mechanisms. This research highlights fermented foods as valuable sources of natural QQ agents and identifies L. plantarum WPL10 as a potential biocontrol agent for improving food safety by reducing bacterial virulence and biofilm formation.