Quercetin and rutin as a dual approach to antibacterial and anti-biofilm activity via iron chelation mechanism

Antibiotic resistance has emerged as a critical global health challenge, limiting effective treatment options and hindering the development of potent alternatives. Iron chelation has surfaced as a promising therapeutic strategy against bacterial pathogens by reducing their pathogenicity and virulence through iron deprivation. This study investigates the effects of quercetin and rutin on bacterial proliferation, biofilm formation, and their synergistic interactions with antibiotics. The chelation activity of these flavonoids was quantified using the Ferrozine method, while antibacterial efficacy was evaluated through agar well diffusion assays. Additionally, antibiofilm activity and density functional theory calculations were conducted to provide further insights into their mechanisms of action. Our findings reveal that quercetin exhibits significantly greater antibacterial activity against both Gram-positive and Gram-negative bacteria compared to rutin. Both flavonoids demonstrated substantial iron-chelating properties and effectively inhibited bacterial growth and biofilm formation. Notably, quercetin and rutin also displayed positive synergistic effects when combined with antibiotic agents. In conclusion, quercetin and rutin represent promising candidates for the development of novel antibacterial therapies, offering potential solutions to combat the growing issue of antibiotic resistance.