不同体积分数洗脱剂对海边月见草茎提取物抗氧化活性的影响

海边月见草茎提取物经X-5大孔树脂吸附,用体积分数为10%、30%、50%、70%的乙醇溶液进行洗脱,得到4种洗脱级分.采用二苯代苦肼自由基(DPPH·)体系、羟自由基体系、超氧阴离子自由基体系及抗卵黄脂蛋白脂质过氧化体系对4个级分的抗氧化活性进行了测定.结果表明,海边月见草茎提取物4种洗脱级分具有不同程度的清除自由基能力,其中30%乙醇级分的抗氧化活性最强.该级分对DPPH自由基的清除率为82.60%,对H2O2/Fe2 产生羟自由基的清除率为65.43%,对邻苯三酚自氧化产生超氧阴离子自由基的抑制率为26.16%,对卵黄脂蛋白PUFA过氧化的抑制率为80.97%.综合评价其抗氧化活性比芦丁好或相当,但比槲皮素略差.同时显示抗氧化活性与其黄酮体积分数有一定的相关性.

Effects of Elution Concentration on the Antioxidant Activity of Stem Extract of Oenothera drummondii Hook.

The crude extract from Oenothera drummondii Hook.stem was adsorbed on macroporous resin X-5,and four fractions were obtained by eluting with 10%,30%,50%,70% ethanol.The antioxidant activity was then characterized by the assays of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical,hydroxyl radical,superoxide anion radical and polyunsaturated fatty acid(PUFA) from lipoprotein.The results showed that four fractions had different scavenging effects on free radical,while the 30% ethanol fraction did the best.The scavenging or inhibition rate of 30% ethanol fraction to DPPH radical,hydroxyl radical generated by Fenton reaction,superoxide anion radical generated by pyrogallol auto-oxidation system and peroxidation of polyunsaturated fatty acid from lipoprotein were 82.60%,65.43%,26.16%,80.97%,respectively.It showed higher or the same antioxidant activity than Rutin,but lower than Quercetin.In addition,the results also showed that there was a close correlation between antioxidant activity and the concentration of total flavonoids of fractions.