响应面法优化树莓鞣花酸提取工艺及其体外抗氧化活性

Optimization of Extraction Technology and Antioxidative Activity of Ellagic Acid in Raspberry by Response Surface Methodology

本研究旨在通过微波辅助提取法确定树莓鞣花酸的最佳提取工艺,并对其抗氧化活性进行研究。以红树莓为实验原料,使用乙醇提取溶剂,采用微波辅助溶剂法提取红树莓中鞣花酸,通过单因素试验与响应面试验优化红树莓中鞣花酸提取工艺,利用高效液相色谱(HPLC)法对鞣花酸进行分析测定,并对其抗氧化性进行研究。结果表明:响应面试验优化出最佳提取条件为:提取时间1.8 min、提取温度60℃、乙醇浓度50%、液料比19∶1、微波功率411 W,此条件下测得鞣花酸提取量为(82.75±1.05) mg/100 g,高于传统盐酸水解法在最佳提取条件下所测树莓鞣花酸提取量。实际结果与理论预测高度吻合,因此本实验得到的最优条件准确可靠有参考应用价值。微波辅助溶剂法所得鞣花酸对羟自由基清除能力、清除DPPH自由基能力都显著高于传统盐酸水解法所得鞣花酸对羟自由基清除能力,清除DPPH自由基能力,说明微波辅助溶剂提取法,不但提取时间短暂,提取溶剂用量少,而且更好的保护了树莓鞣花酸的抗氧化活性,可为树莓鞣花酸工业生产提供一定参考。

The aim of this study was to determine the optimal extraction process of raspberry ellagic acid by microwave-assisted extraction and study its antioxidant activity.Red raspberry was used as experimental material,ethanol extraction solvent was used,and ellagic acid was extracted from red raspberry by microwave-assisted solvent method.The extraction process of ellagic acid in red raspberry was optimized by single factor test and response surface test.The ellagic acid was analyzed by chromatography(HPLC) and its oxidation resistance was investigated.The results showed that the optimal extraction conditions were as follows:extraction time 1.8 min,extraction temperature 60 ℃,ethanol concentration 50%,liquid-to-liquid ratio 19∶ 1,microwave power 411 W,the extraction amount of ellagic acid was(82.75 ± 1.05) mg/100 g under these conditions,which was higher than that measured by the traditional hydrochloric acid hydrolysis method under the optimal extraction conditions.The actual results were highly consistent with the theoretical predictions.Therefore,the optimal conditions obtained in this experiment were accurate and reliable and have reference application value.The ability of ellagic acid to scavenge hydroxyl radicals and scavenge DPPH free radicals by microwave assisted solvent method was significantly higher than that of hydroxy acid scavenging ability of ellagic acid obtained by traditional hydrochloric acid hydrolysis method,and the ability to scavenge DPPH free radicals,indicating microwave assisted solvent extraction.The method not only took a short extraction time,but also used less extraction solvent,and better protected the antioxidant activity of raspberry ellagic acid,which could provide a reference for the industrial production of raspberry ellagic acid.