秋葵黄酮的纯化和体外抗氧化活性研究

Purification and Antioxidant Activity in vitro of Flavonoids from Okra

研究通过静态吸附试验比较NKA-9、AB-8、HPD-400、D101等4种大孔树脂对秋葵中黄酮类物质的吸附与解吸性能,并以VC为对照,对其还原力及羟自由基(·OH)、超氧阴离子自由基(O_2^-·)、DPPH自由基(DPPH·)、ABTS^+自由基(ABTS^+·)清除能力进行探讨。结果表明,最适合分离纯化秋葵黄酮的树脂类型为AB-8型,通过动态吸附-洗脱试验得出AB-8树脂分离纯化秋葵黄酮的最佳工艺为上样浓度0.60 mg/m L,上样流速0.70 m L/min,洗脱剂为70%乙醇,洗脱流速0.40 m L/min,纯化后秋葵黄酮纯度由39.2%提高到67.3%。抗氧化结果显示秋葵黄酮对秋葵黄酮总还原力高于VC,对·OH、O_2^-·、DPPH·、ABTS^+·的IC_(50)值分别为0.56、0.42、0.62、0.52 mg/m L,其最大清除率分别为90.4%、80.4%、77.6%、88.4%,具有良好的体外抗氧化活性。

It compares the adsorption and desorption properties of flavonoids of four kinds of macroporous resin：NKA-9,okra AB-8,HPD-400 and D101. The evaluation of antioxidant activity was carried out by reducingpower,hydroxyl,superoxide anion ,DPPH and ABTS＋radical scavenging assays in comparison toVC. Throughthe static adsorption experients to further screen out the best resin type of separation and purification ofFlavonoids from okra is AB-8.Through the dynamic adsorption-elution experients we can conclude that the besttechnique of the AB-8 resin for separation and purification of okra flavonoids is the optimum concentration ofthe sample： 0.60 mg/mL,sample flow rate of： 0.70 mL/min,eluting agent was 70 % ethanol,elution flow rate：0.40 mL/min,the purity of okra flavonoids was increased from 39.2 % to 67.3 %. It turned out that the totalreducing power of okra is higher thanVC,and the IC50 of the flavonoids extracted from okra on hydroxyl,superoxide anion, DPPH and ABTS＋radical scavenging assays were 0.56, 0.42, 0.62,0.52 mg/mL,and themaximum scavenging rates were 90.4%, 80.4%, 77.6 % and 88.4%,respectively. These results support strongantioxidant activity in vitro for okra flavonoids.