槲寄生总黄酮微波提取工艺及其抗氧化活性研究

目的：优化提取槲寄生总黄酮的最佳工艺条件及测定其体外抗氧化活性。方法：以产品中总黄酮的质量分数为指标，正交试验L9(34)对槲寄生的微波辅助萃取工艺参数进行优化，并测定其体外抗氧化活性。结果：槲寄生总黄酮的最佳提取工艺为乙醇溶液体积分数70%、微波萃取功率500W、固液比1:40(g/mL)、萃取温度70℃，提取率达1.88%。其体外清除DPPH 自由基及·OH 的IC50 值分别为0.036mg/mL 和0.572mg/mL。结论：槲寄生总黄酮抗氧化活性明显，且最佳工艺操作简单快捷，适用于工业化大批量提取槲寄生总黄酮。

Microwave-aided Extraction and Free Radical Scavenging Activity of Total Flavonoids from Mistletoe

In this paper, we develop an optimized procedure for the microwave-aided extraction of total flavonoids from mistletoe and test their in vitro scavenging activity against DPPH and hydroxyl (generated in Fenton system) free radicals. The optimization of the procedure for total flavonoids extraction was carried out using single factor and orthogonal array methods, in which the effects of extraction conditions on total flavonoids yield from mistletoe were evaluated. The results showed that the optimum conditions for total flavonoids extraction were as follows: ethanol concentration 70%, microwave power 500 W, solidto- liquid ratio 1:40 (g/mL) and extraction temperature 70 ℃. Under these conditions, the extraction yield of total flavonoids from mistletoe was up to 1.88%. The IC50 values of the extracted total flavonoids for DPPH and hydroxyl free radicals were 0.036 mg/mL and 0.572 mg/mL, respectively. Based on these results, it can be concluded that mistletoe total flavonoids is a promising free radical scavenger and that the developed extraction procedure is simple and convenient and consequently, is most suitable for large-quantity industrial production of mistletoe total flavonoids.