Robak J, Gryglewski R J
Department of Pharmacology, Copernicus Academy of Medicine, Cracow, Poland.
Biochem Pharmacol. 1988 Mar 1;37(5):837-41. doi: 10.1016/0006-2952(88)90169-4.
Seven flavonoids and three non-flavonoid antioxidants, i.e. butylated hydroxyanisole, chlorpromazine and BW 755 C, were studied as potential scavengers of oxygen free radicals. Superoxide anions were generated enzymatically in a xanthine-xanthine oxidase system and non-enzymatically in a phenazine methosulphate-NADH system, and assayed by reduction of nitro blue tetrazolium. The generation of malonaldehyde (MDA) by the ascorbate-stimulated air-oxidised boiled rat liver microsomes was considered as an index of the non-enzymatic formation of hydroxyl radicals. Flavonoids but not non-flavonoid antioxidants lowered the concentration of detectable superoxide anions in both enzymic and non-enzymic systems which generated these SOD-sensitive radicals. The most effective inhibitors of superoxide anions were quercetin, myricetin and rutin. Four out of seven investigated flavonoids seemed also to suppress the activity of xanthine oxidase as measured by a decrease in uric acid biosynthesis. All ten investigated compounds inhibited the MDA formation by rat liver microsomes. Non-flavonoid antioxidants were more potent MDA inhibitors than flavonoids. It is concluded that antioxidant properties of flavonoids are effected mainly via scavenging of superoxide anions whereas non-flavonoid antioxidants act on further links of free radical chain reactions, most likely by scavenging of hydroxyl radicals.
研究了七种黄酮类化合物和三种非黄酮类抗氧化剂，即丁基化羟基茴香醚、氯丙嗪和BW 755 C，作为氧自由基的潜在清除剂。超氧阴离子在黄嘌呤-黄嘌呤氧化酶系统中通过酶促产生，在吩嗪硫酸甲酯-NADH系统中通过非酶促产生，并通过硝基蓝四唑的还原进行测定。抗坏血酸刺激的空气氧化煮沸大鼠肝微粒体产生丙二醛（MDA）被视为羟基自由基非酶形成的指标。黄酮类化合物而非非黄酮类抗氧化剂降低了在产生这些对超氧化物歧化酶（SOD）敏感自由基的酶促和非酶促系统中可检测到的超氧阴离子浓度。超氧阴离子最有效的抑制剂是槲皮素、杨梅素和芦丁。在所研究的七种黄酮类化合物中，有四种似乎也通过尿酸生物合成的减少来抑制黄嘌呤氧化酶的活性。所有十种研究化合物均抑制大鼠肝微粒体的MDA形成。非黄酮类抗氧化剂比黄酮类化合物更有效地抑制MDA。结论是，黄酮类化合物的抗氧化特性主要通过清除超氧阴离子来实现，而非黄酮类抗氧化剂作用于自由基链反应的进一步环节，最有可能是通过清除羟基自由基。
