超声波提取分光光度法测定红枣中的总黄酮

目的]研究红枣中的总黄酮测定方法。方法]样品经甲醇作溶剂的超声波辅助法提取后,用NaNO2-A l（NO3）3-NaOH显色络合,在分光光度计波长为500 nm处测定其吸光度。结果]红枣中黄酮类化合物在0.004 8-0.047 0 mg/m l范围内有良好的线性关系,其回归方程为Y=25.625X＋0.023 7（R=0.999 0）。3种不同产地红枣中的黄酮类化合物含量在65.1-158.6 mg/100 g。结果表明,红枣中总黄酮含量与产地及红枣部位有关,以清涧黄河边的新鲜红枣中总黄酮含量最高,枣皮部总黄酮含量高于枣肉和枣核。结论]建立了超声波辅助法提取、分光光度法准确测定红枣中总黄酮含量的新方法。

Determination of the Content of Total Flavonoids in Red Jujube with Ultrasonic Extraction and Spectrophotometry

Objective] A new method for the ultrasonic extraction and spectrophotometric determination of the flavonoids in red jujube was researched.Method] The absorbance of the flavonoid,which was extracted with the ultrasonic method under the methanol as solvent from red jujube,and then,colorfully compounded by NaNO2-Al(NO3)3-NaOH,was measured with spectrophotometer in at λmax of 500 nm.Result] The flavonoid compounds from red jujube were with a good linear relationship in the range of 0.004 8-0.047 0 mg/ml and its regression equation was Y=25.625X+0.023 7(R=0.999 0).The content of flavonoids from the red jujube of three different areas was in the range of 65.1 mg/100 g ~ 158.6 mg/100 g.The results showed that the content of flavonoids in red jujube was related to the origin and parts of jujube.The highest content of flavonoids was in the red jujube from the Qingjian region near the Yellow River and the content of flavonoids in jujube skin was higher that of its pulp and stone.Conclusion] The method of the flavonoids extracted with ultrasonic technique from red jujube and the content of flavonoids accurately measured with spectrophotometer was set up.