Quorum quenching mediated virulence factor impairment by Pandanus tectorius leaf extract against Chromobacterium violaceum

This study investigated the anti-quorum sensing ability of Pandanus tectorius (PT) leaf extract in suppressing virulence factors including biofilm formation in Chromobacterium violaceum under in vitro conditions. The extract significantly inhibited the biosynthesis of violacein, acyl homoserine lactone, chitinase, exopolysaccharides, haemolysin, and outer membrane vesicles at sub-MIC concentrations of 1.5, 1, and 0.5 mg/ml. Biofilm formation was reduced by 81.46% at a concentration of 1.5 mg/ml. PT leaf extract also downregulated the quorum sensing-associated genes, including cviI, cviR, and vioA of C. violaceum. GC-MS analysis identified 15 major bioactive compounds, which were docked with the cviR master regulator protein. Among those, stigmasterol demonstrated efficient binding at the active site of cviR, with a binding energy of −8.5 kcal/mol. Toxicity assays confirmed the non-toxic nature of the PT extract, highlighting its potential as a safe anti-quorum sensing agent.