柚皮黄酮抑制硝化和氧化作用的研究

The Inhibition Effects of Shaddock Pericarp Flavonoids on Nitration and Oxidation

以抑制过氧亚硝酸根硝化酪氨酸生成3-硝基酪氨酸评价了柚皮黄酮的抗硝化作用;以Fenton反应产生羟基自由基体系和邻苯三酚自氧化产生超氧阴离子自由基体系,用紫外可见分光光度法测定了柚皮黄酮对羟基自由基和超氧阴离子自由基的清除效果。结果表明,柚皮苷的抗硝化作用较强,而芦丁和橙皮苷没有明显的抗硝化作用;3种柚皮黄酮清除羟基自由基的效果在μg.mL-1水平就已经比较显著(超过50%),且显示出浓度依赖性,作用大小依次为:柚皮苷>橙皮苷>芦丁;3种柚皮黄酮在μg.mL-1水平清除超氧阴离子自由基的作用大小依次为:芦丁>柚皮苷>橙皮苷。

In this paper, we evaluated the nitration-resistance of the shaddoek pericarp flavonoids by restrai- ning peroxynitrite from nitrifying tyrosine to generate 3-nitrotyrosine （3-NT）. With Fenton reaction producing hydroxyl free radicals and pyrogallol auto-oxidation system producing superoxide anion free radical,the ability of shaddock periearp flavonoids in removing hydroxyl free radieals and superoxide anion free radicals was detected by UV-Vis spectrophotometric method. The results showed that the nitration-resistance effect of naringin was strong,but those of rutin and hesperidin were weak. The three flavonoids had significant effects on remo- ving hydroxyl free radicals at the levels of μg·mL^-1 with over 50% of hydroxyl free radical clearance, which followed the order of naringin〉 hesperidin 〉rutin. The three shaddock pericarp flavonoids all displayed the dependence of removing hydroxyl free radical on concentration. The effects on removing superoxide anion free radical followed the order of rutin 〉 naringin 〉 hesperidin at the levels of μg·mL^-1 .