桃叶中黄酮的提取及测定研究

Study on Extraction of Flavonoids in Peach Leaves

探讨了桃树叶中黄酮的提取方法,研究了溶剂浸提温度、时间、固液比、乙醇浓度,超声波或微波辅助等对桃叶中黄酮提取效果的影响。研究结果表明:溶剂浸提中,影响因素依次为:料液比>乙醇浓度>浸提温度>水浴时间;超声波辅助提取中则为乙醇浓度>料液比>浸提温度>超声时间;微波提取中则又为微波时间>微波功率>料液比>乙醇浓度。用70%乙醇作为浸提溶剂,料液比1∶25,温度控制在30℃,1次浸提40 min,桃叶黄酮提取率1.81%;采用超声波辅助提取,料液比为1∶30,浸提温度控制在50℃,提取30 min,用70%乙醇提取桃叶黄酮,提取率最高达3.98%;使用微波辅助提取时,料液比1∶30,微波功率控制在200 W,用60%乙醇提取30 s,则黄酮提取率3.92%。由此可见,纯粹用溶剂提取,提取率较低,不到2%,采用超声波或微波辅助提取,可达近4.0%。

The extraction of flavonoids in peach leaves was studied. The factors, such as extraction temperature, time, solid-liquid ratio, ethanol concentration, extraction under ultrasonic or microwave, were studied were. The results indicated that the ranking of influence was： solid-liquid ratio〉ethanol concentration〉extraction temperature〉time. Under ultrasonic the ranking was： ethanol concentration〉solid-liquid ratio〉extraction temperature〉time. Under microwave the ranking was： time〉microwave power〉 solid-liquid ratio〉 ethanol concentration. With 70% ethanol as extraction solvent, solid-liquid ratio 1 ： 25, temperature 30 ~C, extraction time 40 rain, the extraction rate was 1.81%. Under ultrasonic the rate was 3.98%, when the extraction condition was solid-liquid ratio 1 ： 30, the temperature 50℃, extraction time 30 rain, 70% ethanol. Under microwave the rate was 3.92%, when the extraction condition was solid-liquid ratio 1 ： 30, microwave power 200 W, 60% ethanol, time 30 s. So extracted only by solvent the extraction rate was less than 2%. Under ultrasound or microwave the rate was nearly 4.0%.