Antibiofilm and anti-quorum sensing activity of < i > Psidium guajava < /i > L. leaf extract: < i > In vitro < /i > and < i > in silico < /i > approach

In this study, we evaluated the antibacterial, anti-quorum sensing, and anti-biofilm activities ofPsidium guajava L. methanolic leaf extracts (PGME). Minimum Inhibitory Concentrations (MICs) of PGME were determined as 500 μg/ml forC.violaceum and 1000 μg/ml forP.aeruginosa PAO1. Significantly, even at sub-MIC concentrations, PGME exhibited noteworthy anti-quorum sensing properties, as evidenced by concentration-dependent inhibition of pigment production inC.violaceum 12742. Furthermore, PGME effectively suppressed quorum-sensing controlled virulence factors inP.aeruginosa PAO1, including biofilm formation, pyoverdin, pyocyanin, and rhamnolipid production, with concentration-dependent inhibitory effects. Phytochemical analysis utilizing GC-MS revealed the presence of compounds such as alpha-copaene, caryophyllene, and nerolidol.In-silico docking studies indicated a plausible mechanism for the observed anti-quorum sensing activity, involving favorable binding and interactions with QS-receptors, including RhlR, CviR ’, LasI, and LasR proteins. These interactions were found to potentially disrupt QS pathways through suppression of AHL production and receptor protein blockade. Collectively, our findings propose PGME as a promising candidate for the treatment of bacterial infections. Its attributes that mitigate biofilm development and impede quorum-sensing mechanisms highlight its potential therapeutic value.
Source: PLoS One - Category: Biomedical Science Authors: Source Type: research