萝卜叶黄酮的超声波辅助提取工艺及抗氧化活性研究

Optimization of Ultrasonic-assisted Extraction Technology and Antioxidant Activities of Flavonoids in Radish Leaves

用超声波辅助乙醇提取萝卜叶中的黄酮。通过单因素试验与四元三次正交试验,对黄酮的超声波辅助醇提工艺进行优化,以体外清除(·OH)和(O_2^(-·))的能力为指标,研究萝卜叶黄酮的抗氧化活性。最优条件:乙醇浓度为60%,料液比为1:15(m∶V),超声波处理15 min,在50℃下浸提30 min,该条件下黄酮提取率为1.41%,是传统浸提法的200%;萝卜叶黄酮对·OH和O_2^(-·)均有明显的清除作用,在试验剂量下,清除效果随着黄酮浓度的增加而增强,对·OH和O_2^(-·)的半数抑制率(IC50)分别为0.643 8、1.523 1 mg/m L。结果表明:超声波辅助提取是一种高效的提取萝卜叶黄酮方法,其抗氧化活性较高。

Total flavonoids were extracted from radish leaves using ethanol as extraction solvent with the aid of ultrasonic treatment. Five single-factor experiments with four factors triple orthogonal design was adopted to research the ultrasonic-assisted ethanol extraction process of flavonoids in the water bath. The scavenging abilities against hydroxyl radicals （·OH） and （O2-） in vitro of flavonoids were determined. The results indicated that the optimum extraction parameters were as follows： the volum fraction of ethanol was 60%, solid-liquid ratio was 15 （m：V）, ultrasonic treatment 15min, immerse 30 min under the temperature of 50 ~C. Under these conditions, the extraction rate of total flavonoids is up to 1.41%, was the traditional extraction method of 200%. Flavonoids of radish leaves can effectively scavenge ·OH and O2^-, and the role of these effect increased with the increase of flavonoids concentration, IC50 were 0.643 8, 1.523 1 mg/mL. These results demonstrated that UAE was a highly effective way to extract flavonoids from radish leaves and the antioxidant activity of flavonoids was high.