抄録
We evaluated the efficacy of flavonoid quercetin as an antioxidant in hepatic lysosomal fractions of mice using the hydrophilic radical generator 2, 2'-azobis(2-amidinopropane) dihydrochloride (AAPH) and the lipophilic radical generator 2, 2'-azobis(2, 4-dimethylvaleronitrile) (AMVN). Quercetin inhibited lipid peroxidation in lysosomal fractions, measured as thiobarbituric acid reactive substances (TBARS), and inhibited the release of lysosomal enzymes more obviously against AAPH than against AMVN. Whereas inhibitory effects of quercetin on lipid peroxidation were weaker than those of the synthetic lipophilic antioxidant 2, 6-di-tert-butyl-p-cresol (BHT), lysosomal fractions preloaded with quercetin effectively quenched 1, 1-diphenly-2-picrylhydrazyl radicals, similar to BHT. Rutin, a glycoside of quercetin, was less potent than quercetin in these experiments. These findings suggest that quercetin could have potent antioxidative activity in the spaces between an aqueous phase and a lipid phase in biological systems owing to the localization within membranes as well as evident antioxidative activity.
