响应面法优化蒲桃叶总黄酮的提取工艺及其抗氧化活性

Optimization of Total Flavonoid Extraction from Syzygium jambos Leaves by Response Surface Methodology and Its Antioxidant Activity

为研究蒲桃叶总黄酮的提取工艺及其抗氧化活性,以蒲桃叶为原料,采用微波辅助法提取其总黄酮。以单因素试验为基础,选择乙醇体积分数、液料比、微波功率、微波时间为自变量,总黄酮提取率为因变量,对蒲桃叶中总黄酮的提取工艺进行响应面优化。结果表明蒲桃叶总黄酮最优提取工艺为乙醇体积分数59%、液料比53∶1(mL/g)、微波功率400 W、微波时间3.9 min,在此条件下蒲桃叶总黄酮的提取率为5.13%。体外抗氧化试验结果表明,蒲桃叶总黄酮提取液对羟基自由基、DPPH自由基的半数抑制浓度(IC_(50))分别为120、9.19μg/mL,蒲桃叶总黄酮对DPPH自由基有较强的清除能力,对羟基自由基有一定的清除能力。

In order to study the extraction process of total flavonoids from Syzygium jambos leaves and their antioxidant activity,microwave-assisted extraction was used to extract total flavonoids from these leaves.Based on single-factor methodology,the response surface methodology was designed to optimize the extraction process of total flavonoids from Syzygium jambos leaves,with ethanol volume fraction,liquid-material ratio,microwave power,and microwave time as independent variables and total flavonoid extraction rate as the dependent variable.Results showed that the optimum extraction conditions were as follows:ethanol volume fraction 59%,liquid-material ratio 53∶1(mL/g),microwave power 400 W,and microwave time 3.9 min.The extraction rate of total flavonoids from Syzygium jambos leaves was 5.13%under these conditions.In vitro antioxidant activity was also investigated,which showed that the IC_(50) values of total flavonoids from Syzygium jambos leaves were 120μg/mL and 9.19μg/mL for hydroxyl radicals and 1,1-diphenyl-2-picrylhydrazyl(DPPH)free radicals,respectively.Total flavonoids from Syzygium jambos leaves had strong scavenging ability for DPPH free radicals and some scavenging ability for hydroxyl radicals.