Phenolic free-radical scavenging

Phenolic free-radical scavenging is a biochemical mechanism by which phenolic compounds, such as flavonoids and polyphenols, neutralize reactive oxygen species (ROS) and other free radicals [PMID: 24019280]. This process primarily involves the donation of a hydrogen atom or an electron to a radical species, resulting in the formation of a resonance-stabilized phenoxyl radical that is significantly less reactive [PMID: 16029933]. By intercepting these highly reactive molecules, phenolic compounds prevent oxidative damage to critical cellular components, including DNA, proteins, and lipids [PMID: 23675073]. Although this mechanism is a cornerstone of antioxidant therapy and is utilized by numerous natural products like quercetin and resveratrol, it represents a chemical process rather than a specific molecular target such as a receptor or enzyme [PMID: 21130297]. This pathway is crucial for mitigating oxidative stress, which is a major contributor to the pathogenesis of chronic conditions like cardiovascular disease, cancer, and neurodegeneration [PMID: 23675073]. However, the therapeutic application of these compounds is often complicated by poor systemic bioavailability and the potential for pro-oxidant effects at high concentrations [PMID: 18496811].

Other names

Polyphenolic antioxidant activityRadical scavenging activityHydrogen atom transfer (HAT)Single electron transfer (SET)Phenolic antioxidant mechanism

Phenolic compounds act as antioxidants by donating a hydrogen atom or an electron to neutralize reactive oxygen species (ROS) and free radicals, forming a resonance-stabilized phenoxyl radical that is less reactive.