Inhibitory effects of the herbal quorum sensing quencher isoorientin on spoilage characteristics of Serratia liquefaciens S01: In vitro and in a smoked chicken leg model.

The study aimed to screen herbal-derived quorum sensing (QS) quenchers and investigate their inhibitory effects on the Serratia liquefaciens S01, a specific spoilage bacterium in smoked chicken legs. Targeting the QS proteins LuxI and LuxR of S. liquefaciens S01, ten compounds were screened as potential QS quenchers by molecular docking. Among these compounds, isoorientin exhibited a relatively low minimum inhibitory concentration (MIC, 250 μg/mL), potent quorum quenching activity, and the strongest binding affinity. In vitro experiments, sub-MIC concentrations of isoorientin significantly inhibited extracellular polysaccharide production, and biofilm formation of S. liquefaciens S01 (P < 0.05). During the storage of smoked chicken legs at 4 °C, the 125 μg/mL isoorientin treatment exhibited significantly lower total viable counts (5.45 log CFU/g) and thiobarbituric acid reactive substances values (1.15 mg/kg) than the other treatments (P < 0.05), and effectively delayed the decline in sensory quality of the smoked chicken legs. This study provides important theoretical insights for delaying meat product spoilage and developing natural QS quenchers.