acid-phosphatase and 2-2--azobis(2-4-dimethylvaleronitrile)

We assessed the antioxidative effects of quercetin-feeding on ddY strain male mice by measuring luminol-amplified chemiluminescence that was enhanced by a hydrophilic free radical initiator 2, 2'-azobis(2-amidinopropane) dihydrochloride. Quercetin suppressed chemiluminescent intensity in a dose-dependent manner in vitro with a half-inhibition concentration (IC(50)) of 3x10(-8) M, which was lower than the value of synthetic antioxidant 2, 6-di-tert-butyl-p-cresol (IC(50): 7x10(-7) M). Lysosomal (12000xg pellet) and supernatant fractions obtained from the livers of mice fed a diet containing 0.2% quercetin for 7 days showed more inhibition of chemiluminescent intensity than those from non-treated mice. Quercetin feeding also resulted in the inhibition of lipid peroxidation as determined by a thiobarbituric acid reactive substance test which detected suppression of the release of lysosomal enzymes induced by lipophilic free radical initiator 2, 2'-azobis(2,4-dimethylvaleronitrile). These results probably reflect radical quenching activity of quercetin, indicating that the measurement of chemiluminescence is a useful tool for the assessment of total antioxidant activity in biological systems.

Topics: Acetylglucosaminidase; Acid Phosphatase; Administration, Oral; Amidines; Animals; Azo Compounds; Butylated Hydroxytoluene; Dose-Response Relationship, Drug; Lipid Peroxidation; Liver; Luminescent Measurements; Luminol; Lysosomes; Male; Mice; Mice, Inbred Strains; Nitriles; Oxidants; Phenols; Quercetin; Subcellular Fractions; Thiobarbituric Acid Reactive Substances