Antibiofilm and Antivirulence Efficacies of Flavonoids and Curcumin Against .

is well adapted to hospital environments, and the persistence of its chronic infections is mainly due to its ability to form biofilms resistant to conventional antibiotics and host immune systems. Hence, the inhibitions of biofilm formation and virulence characteristics provide other means of addressing infections. In this study, the antibiofilm activities of twelve flavonoids were initially investigated. Three most active flavonoids, namely, fisetin, phloretin, and curcumin, dose-dependently inhibited biofilm formation by a reference strain and by several clinical isolates, including four multidrug-resistant isolates. Furthermore, the antibiofilm activity of curcumin (the most active flavonoid) was greater than that of the well-known biofilm inhibitor gallium nitrate. Curcumin inhibited pellicle formation and the surface motility of . Interestingly, curcumin also showed antibiofilm activity against and mixed cultures of and . molecular docking of the biofilm response regulator BfmR showed that the binding efficacy of flavonoids with BfmR was correlated with antibiofilm efficacy. In addition, curcumin treatment diminished virulence in an model without cytotoxicity. The study shows curcumin and other flavonoids have potential for controlling biofilm formation by and the virulence of .