葡萄皮渣中花旗松素提取工艺优化及其抗氧化能力测定

采用乙醇加热法提取葡萄花旗松素，利用响应面分析法优化葡萄花旗松素的提取工艺并测定其最优组的抗氧化性能。结果表明:葡萄花旗松素的最佳提取工艺为静置处理时间为30 min、乙醇含量58%、提取温度56℃、液料比23:1 mL/g、提取时间2.0 h，最佳提取量为3.936 mg/g。以V_C为参照测定提取液对ABTS自由基、DPPH自由基和铁离子还原力，其中葡萄花旗松素提取液对自由基清除能力及铁离子还原力均高于V_C溶液，对DPPH自由基的清除效果最好，浓度为50 μg/mL的提取液对DPPH自由基的清除率可达到90%。此外，研究还表明花旗松素提取液对ABTS自由基、DPPH自由基的IC₅₀值分别为28.15、22.65 μg/mL。本结果对于葡萄皮渣的开发利用具有一定的意义。

Optimization of Extraction Process of Taxifolin from Grape Pomace and Determination of Its Antioxidant Capacity

The ethanol heating method was used to extract grape pomace,and response surface methodology was used to optimize the extraction process.Then the antioxidant activity was determined in the optimal group.The results showed that the optimum extraction conditions were as follows:standing time 30 min,ethanol content 58%, extraction temperature 56 ℃,liquid-solid ratio 23:1 mL/g, extraction time 2.0 h,and the optimum extraction amount was 3.936 mg/g.Taking Vc as reference,the scavenging ability of grape taxifolin extract to ABTS free radical,DPPH free radical and iron ion reducing power was higher than that of Vc solution,and the scavenging effect on DPPH free radical was the best.The scavenging rate of 50 μg/mL extract on DPPH free radical could reach 90%.In addition,the IC₅₀ values of the extracts of taxifolin to ABTS and DPPH free radical were 28.15 and 22.65 μg/mL, respectively.The results are significant for the development and utilization of grape pomace.