荧光分析法测定野生葎草叶中总黄酮的含量

目的]建立荧光分光光度法测定襻草中总黄酮含量的方法。方法]用75％乙醇印℃超声提取荐草叶的有效成分，以芦丁为标样，选择410和534nm为激发波长和发射波长，研究溶剂、pH值及静置时间对荧光强度的影响。结果]最佳测定条件为：10％Al（NO3）3溶液的加入量以4ml为宜，加入pH值为4．1的醋酸-醋酸钠缓冲液2．5ml，60％乙醇作溶剂，溶液静置时间以25min为宜，用该法检出的野生律草叶中的总黄酮含量达52．98mg／g，检出限达9．43×10^-7mol／L。荧光强度与芦丁浓度在1．55×10^-6～1．31×10^-5mol／L内具有良好的线性关系，其回归方程为y=2．816x＋0．291，相关系数r为0．9966。平均回收率为100．5％，RSD为0．54％。结论]用荧光分光光度法测定律草叶中总黄酮含量的精密度和准确度较高，且操作简便，成本低。

Determination of Total Flavone Content in Wild Japanese hop Leaf by Fluorescence Spectrophotometry

Objective ] The research aimed to establish the method of determining the total flavone content in Japanese hop leaf by fluorescence spectrophotometry. Method] The effective components were extracted by ultrasonic with 75% ethanol at 60 ℃ from J. hop leaf, with rutin as standard sample, 410 and 534 nm were selected as excitation and emission wavelengths to study the effects of solvent, pH value and standing time on fluorescence intensity. Result ] The best determining conditions were as follows ： The suitable addition amount was 4 ml for 10% AI（ NO3 ） 3, the addition of acetic acid-sodium acetate buffer with pH value of 4.1 was 2.5 ml,60% ethanol was selected as solvent and the suitable standing time of solution was 25 min. The total flavone content detected by this method in wild J. hop leaf was up to 52.98 mg/g and its detection limit was 9.43 × 10^-7 mol/L. The fluorescence intensity had a good linear relationship with rutin concn, in the range of 1.55 × 10^-6 -1.31× 10^-5 mol/L with the regression equation of y = 2. 816 x ＋ 0.291, correlation coefficient of 0. 996 6, average recovery of 100.5% and RSD of 0.54%. Conclusion] The method of determining the total flavone content in J. hop leaf by fluorescence spectrophotometry had relatively high precision and v accuracy and was easy to operate and low in cost.