酸角叶中总黄酮的提取及清除羟自由基的作用研究

目的]优选酸角叶中总黄酮的提取条件,并对其清除羟自由基的作用进行研究.方法]采用乙醇回流法提取酸角叶中的总黄酮,通过单因素确定总黄酮提取的较佳试验条件,并对总黄酮的清除羟基自由基（·OH）的作用进行对比试验.结果]确定酸角叶中总黄酮的最佳提取条件为：乙醇浓度为70％,料液比为1∶30（W/V,g/ml,下同）,回流温度为85℃,提取时间为2.5 h;在此条件下,酸角叶中总黄酮的提取率为1.83％.羟基自由基（·OH）的清除作用对比试验表明,抗氧化活性大小依次为：提取液中总黄酮＞芦丁＞BHT.结论]该方法优选了酸角叶中总黄酮的最佳测定条件,并发现其对羟自由基有较强的清除作用.

Study on Extraction of Flavonoids from Tamarind Leaves and Scavenging Effect on Hydroxyl Radicals

Objective ] The aim was to study extraction of flavonoids and scavenging effect on hydroxyl radicals Method] Flavonoids were ex- tracted from tamarind leaves by using ethanol reflux method from tamarind leaves, and the preferred extraction conditions were determined by sin- gle factor experiment. Result] The study showed that the best extraction conditions was ethanol concentration of 70%, solid-liquid ratio of 1：30 （mg/ml）, reflux temperature of 85 ~C and extraction time of 2.5 h. The extraction ratio of flavonoids was 1.83% by using spectrophotometry. Antioxidant effects of flavonoids, rutin and BHT were measured to remove hydroxyl radicals by comparative experiments. Antioxidant activity was ordered as flavonoids 〉 rutin 〉 BHT. Conclusion] Antioxidant experiments showed that flavonoids from tamarind leave had a strong scavengirtg effect on hydroxyl radicals.