Inhibition of quorum sensing-dependent biofilm and virulence genes expression in environmental pathogen Serratia marcescens by petroselinic acid.

The aim of this study was to evaluate the anti-biofilm and anti-virulence properties of petroselinic acid (PSA) against the environmental pathogen Serratia marcescens. PSA significantly inhibited the quorum sensing (QS)-dependent virulence factors such as prodigiosin, protease productions, and biofilm formation in S. marcescens. The antibiofilm potential of PSA was also confirmed through light, confocal laser scanning, and scanning electron microscopic analyses. Furthermore, PSA effectively inhibited the biofilm-related phenomena such as exopolysaccharide production, hydrophobicity production, swimming, and swarming motility without affecting the bacterial growth. In FT-IR analysis, the PSA treated S. marcescens cells displayed a reduction in cellular components compared to the untreated controls. The real-time analysis revealed the downregulation of QS-controlled virulence genes such as bsmB, fimA, fimC, and flhD in S. marcescens on treatment with PSA. The obtained results strongly suggested that PSA could be further explored as an antipathogenic drug to treat QS-mediated infections caused by S. marcescens.