超声辅助浸提–紫外分光光度法测定酸枣中黄酮

Determination of flavonoids in jujuba by ultrasonic assisted extraction–ultraviolet spectrophotometry

建立超声辅助浸提法提取酸枣中黄酮的方法。以雅安碧峰峡野生酸枣为研究对象,通过单因素实验考察提取条件对黄酮提取率的影响,采用自由基清除(DPPH)法研究果皮粗黄酮提取物的抗氧化活性。在料液比为1∶30(g/mL),乙醇体积数为80%,浸泡时间为4 h,超声温度为80℃,超声时间为30 min时提取黄酮效果最好,果皮中黄酮含量为7.76%。果皮粗黄酮提取物对DPPH具有较好的抗氧化活性,其半数抑制浓度(IC50)为0.5171 mg/mL。测定结果的相对标准偏差为0.54%(n=6),加标回收率在93.5%~100.6%之间。该方法具有较好的精密度与准确度,适用于酸枣中黄酮的提取。

The method for extracting flavonoids from sour jujube by ultrasonic assisted extraction was established.Taking Bifengxia wild sour jujube as the research object,the effect of extraction conditions on the extraction rate of flavonoids was investigated by a single factor.And the antioxidant activity of the crude extracts of the skin was studied by using DPPH method.Test result show when the solid-liquid ratio was 1∶30(g/mL),the concentration of ethanol was 80%,the immersion time was 4 hours,the ultrasonic temperature was 80℃and the extraction time was 4 hours,the content of flavonoids in the skin of wild sour jujube was the highest,which was 7.76%.The crude extracts of the skin have good antioxidation activity on DPPH,and its inhibition concentration(IC50)was 0.5171 mg/mL.The relative standard deviation of determination results was 0.54%(n=6).The standard recoveries rate were 93.5%-100.6%.The method has high accuracy and precision,which is suitable for extracting flavonoids from sour jujube.