Antioxidant and pro-oxidant actions of the plant phenolics quercetin, gossypol and myricetin. Effects on lipid peroxidation, hydroxyl radical generation and bleomycin-dependent damage to DNA.
Abstract
The plant-derived phenolic compounds gossypol, quercetin and myricetin are powerful inhibitors of iron-induced lipid peroxidation in rat liver microsomes, under all five experimental conditions tested and at low micromolar concentrations (IC50 less than or equal to 1.5 microM). However, they greatly accelerate the generation of hydroxyl radicals (.OH) from H2O2 in the presence of Fe3+-EDTA at pH 7.4, as measured by the deoxyribose assay. At 100 microM, the three phenolic compounds enhanced .OH formation up to eight-fold. The hydroxyl radical generation was inhibited by catalase and superoxide dismutase, suggesting a mechanism in which the phenols oxidize to produce superoxide radical, which then assists .OH generation from H2O2 in the presence of Fe3+-EDTA. At concentrations up to 75 microM, quercetin and myricetin also accelerate bleomycin-dependent DNA damage in the presence of Fe3+, possibly by reducing the Fe3+-bleomycin-DNA complex to the Fe2+ form. Hence these naturally-occurring substances can have pro-oxidant effects under some reaction conditions and cannot be classified simplistically as "antioxidants".
Read the paper
Related studies
- Quercetin Influences Quorum Sensing in Food Borne Bacteria: In-Vitro and In-Silico Evidence
- Phenolic-protein interactions: insight from in-silico analyses – a review
- In Silico Discovery of Candidate Drugs against Covid-19
- Neuropharmacological Effects of Quercetin: A Literature-Based Review
- In vitro and in silico anti-dengue activity of compounds obtained from Psidium guajava through bioprospecting
- Effect of Quercetin Rich Onion Extracts on Bacterial Quorum Sensing
Go deeper in Evidence Hub
Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.