Mechanisms of Action of Flavonoids: Antioxidant, Antibacterial and Antifungal Properties

Abstract

Flavonoids, a diverse group of natural polyphenolic compounds found in various sources like fruits and vegetables, have garnered attention for their diverse biological activities, including antioxidant, antibacterial, and antifungal properties. This comprehensive review delves into the mechanisms through which flavonoids combat oxidative stress and hinder the growth of bacteria and fungi. In terms of antioxidative action, flavonoids showcase their efficacy by neutralizing reactive oxygen species through hydrogen atom and electron donation, augmenting endogenous antioxidant enzyme activity, and chelating transition metal ions. Their antibacterial effects target both Gram-positive and Gram-negative bacteria, disrupting cell membranes, inhibiting key enzymatic processes, and suppressing efflux pumps, collectively impeding bacterial growth, and causing cell death. Additionally, flavonoids exhibit antifungal properties by interfering with fungal cell membrane integrity, disrupting ergosterol biosynthesis, and modulating critical signal transduction pathways, ultimately hindering fungal growth and pathogenicity. This nuanced understanding of flavonoid mechanisms not only holds promise for therapeutic development but also inspires future advancements in pharmacological research.