山药皮中黄酮、多酚提取工艺优化及其抗氧化活性

Optimization of Extraction Technology and Antioxidant Activity of Flavonoids and Polyphenols from Yam Skin

为研究山药皮黄酮、多酚的高效提取工艺及其粗提物的抗氧化能力,以山药皮为原料,采用正交法优化超声辅助乙醇提取山药皮中的黄酮、多酚工艺,并对粗提物进行抗氧化活性测定。结果表明:山药皮中黄酮、多酚提取工艺的最佳提取条件为超声时间30 min、乙醇浓度60%、液固比60∶1(mL/g),在此条件下,黄酮得率为0.929%,多酚得率为0.519%。在一定浓度范围内,粗提物的抗氧化能力随着质量浓度的增加而增强,粗提物具有良好的羟自由基清除作用(IC50值为0.083 mg/mL),具有一定的DPPH自由基清除作用(IC50值为0.158 mg/mL),当粗提物质量浓度为1.0 mg/mL时,其羟自由基清除率、DPPH自由基清除率、还原力和抗氧化能力分别为81.84%、79.95%、0.70和0.68。

To investigate the efficient extraction process and antioxidant activity of flavonoids and polyphenols from yam skin,this study used orthogonal design method to optimize the ultrasound-assisted ethanol extraction process for flavonoids and polyphenols from yam skin,and determined the antioxidant activity of the crude extract.The results showed that the optimal extraction conditions for flavonoids and polyphenols from yam skin were as follows:ultrasound time of 30 min,ethanol concentration of 60%,and liquid-to-solid ratio of 60∶1(mL/g).Under these conditions,the yield of flavonoids was 0.929%and the yield of polyphenols was 0.519%.Within a certain concentration range,the antioxidant activity of the crude extract increased with an increase in mass concentration.The crude extract exhibited good hydroxyl radical scavenging activity(IC50 of 0.083 mg/mL)and certain DPPH radical scavenging activity(IC50 of 0.158 mg/mL).When the mass concentration of the crude extract was 1.0 mg/mL,the hydroxyl radical scavenging rate,DPPH radical scavenging rate,reducing power,and antioxidant activity were 81.84%,79.95%,0.70,and 0.68,respectively.