绿豆皮中黄酮类化合物的抗氧化活性及其结构分析

本文旨在分析绿豆皮中黄酮类化合物的抗氧化活性及其结构。采用20%、40%、60%、80%乙醇对绿豆皮黄酮粗提物进行梯度洗脱纯化，以总抗氧化能力（total antioxidative capability，T-AOC）、1，1-二苯基-2-三硝基苯肼（1, 1-diphenyl-2-picrylhydrazyl，DPPH）自由基清除能力、2，2′-联氨-双-3-乙基苯并噻唑啉-6-磺酸（2, 2′-azinobis-3-ethylbenzothia zoline-6-sulphonic acid，ABTS）自由基清除能力、羟自由基清除能力等为指标，筛选出具有最高抗氧化活性的组分，并对其进行结构鉴定。结果表明，60%洗脱液中绿豆皮黄酮的抗氧化能力最强，其DPPH自由基清除能力为48.03%；ABTS+自由基清除能力为57.53%；羟自由基清除能力为12.02%；T-AOC的抗氧化活性为207.64 U/mL，显著高于其他洗脱液（P<0.05）。绿豆皮中具有最强抗氧化活性的黄酮类化合物分别包括牡荆素(vitexin)、异牡荆素(isovitexin)及圣草酚-6-C-β-D-吡喃葡萄糖苷(eriodictyol-6-C-β-D-glucopyranoside)。

Antioxidant Activity and Structural Identification of Flavonoids from Mung Bean Hull

This paper aimed to analyze the antioxidant activity and structure of flavonoid compounds extracted from mung bean hull. The product of mung bean hull flavonoid extraction was purified by gradient elution with different concentrations of alcohol, such as 20%, 40%, 60% and 80%. The abilities of various eluents in T-AOC, scavenging of 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical, 2, 2′-azinobis-3- ethylbenzothia zoline-6-sulphonic acid (ABTS) free radical and hydroxyl radicals, and the compounds with high antioxidant activity were analyzed for structure. The results showed that 60% eluent of mung bean hull flavonoid possess strong antioxidant activity, DPPH scavenging capacity was 48.03%, ABTS+ radical scavenging capacity was 57.53%, hydroxyl radicals scavenging capacity was 12.02%, T-AOC was 207.64 U/mL, which was significantly higher than other eluents (P<0.05). The flavonoid compounds mainly consisted of three components, such as vitexin, isovitexin, and saccharol-6-C-β-D-glucopyranoside.