银杏中种皮提取物抗氧化活性的研究

分别采用卵黄脂蛋白多不饱和脂肪酸过氧化体系、超氧阴离子自由基体系、羟自由基体系、二苯代 苦味酰(DPPH)自由基体系以及总抗氧化能力等检测指标,对银杏中种皮采用不同提取方法(微波提取、超声提取、 乙醇和水浸提)获得的黄酮类物质的抗氧化能力进行了对比研究。结果表明,不同提取方法获得的提取液均具有较 强的抗氧化活性,而不同提取工艺可影响银杏中种皮提取液的抗氧化作用及其机理,其中乙醇浸提液对卵黄脂蛋 白过氧化体系的抑制率为50．69％,微波水提液对超氧阴离子和羟自由基的清除能力分别达213．96和411．26 U／L,乙醇超声提取液对DPPH 自由基的清除率及总抗氧化能力分别为89．8％和44．09 U／mL。

Studies on antioxidant activities of extracts from mesosperms of Ginkgo biloba

The antioxidant activities of extracts from mesosperms of Ginkgo biloba,which was obtained by different extracting technologies such as microwave extraction,ultrasonic extraction,ethanol extraction and water extraction,were compared and analyzed through the model system of peroxidation of polyunsaturated fatty acid from yolk lipoprotein,the scavenging effects on superoxide anion free radical,hydroxyl radical,DPPH free radical as well as the total antioxidant capacity.The results showed that these extracts had higher antioxidant activities,and different extracting technologies may have some influence on the antioxidant activities and mechanism of extracts from mesosperms of Ginkgo biloba.The extract by ethanol extraction could inhibit yolk lipid peroxide with the rate of 50.69%.The extract by microwave extraction with water could scavenge O^-·₂ and ·OH,and the scavenging capacities were 213.96 and 411.26 U/L respectively.The extract by ultrasonic extraction with water could scavenge DPPH with the rate of 89.8% and its total antioxidant capacity was 44.09 U/mL.