Abstract:Objective To explore the anti-biofilm effect of vitexin combined with antibiotics on Pseudomonas aeruginosa. Methods Minimal inhibitory concentrations (MICs) of antibiotics to P. aeruginosa were determined by broth microdilution method. And 96-well cell culture plate combined with crystal violet was used to study antibiofilm effect of vitexin alone or combined with antibiotics. Results Vitexin could significantly inhibit P. aeruginosa biofilm formation from 100.00% to (80.00 ± 4.62) % at the concentration ≥ 31.25 μg/ml in a dose-dependent manner (P < 0.05). The MICs of CAZ, CIP, GEN and OFLX were 0.5, 0.5, 2.0 and 8.0 μg/ml, respectively. And vitexin showed synergistic inhibition of PAO1 biofilm formation when combined with sub-MIC of CAZ, CIP, GEN and OFLX, which could reduce the total amount of biofilm from 100.00% to (39.38 ± 5.32) %, (40.31 ± 2.95) %, (23.31 ± 3.95) % and (50.23 ± 3.14) %, respectively (P < 0.05). Conclusions Vitexin significantly inhibitsbiofilm formation of P. aeruginosa, and shows synergistic effect when combined with antibiotics.