微波辅助萃取-分光光度法测定加拿大一枝黄花中总黄酮

采用微波辅助萃取，以分光光度法测定加拿大一枝黄花中黄酮类化合物的含量。并通过单因素实验和正交试验优化溶剂浓度、液固比、微波功率和微波辐射时间等微波提取条件，确定了微波辅助萃取法提取加拿大一枝黄花中黄酮类化合物的最佳条件为：乙醇浓度50％，液固比40：1，微波功率700w，微波辐射时间20min。在上述最优条件下进行了精密度和回收率实验，相对标准偏差为1．68％（n=51，回收率在97．6％～101．0％之间。利用最佳提取工艺对加拿大一枝黄花根、茎、叶和花中总黄酮含量进行比较，结果表明叶中黄酮类化合物的含量最高；与传统的索式提取法和超声波提取法相比，微波辅助萃取法具有提取效率高、操作简便、经济可靠等优点。

Determination of Total Flavones from the Solidago canadensis by Microwave-Assisted Extraction and Absorption Spectroscopy

Determination of total flavones from Solidago canadensis by microwave-assisted extraction and absorption spectroscopy was reported. The effects of solvent concentration, ratio of liquid to solid, microwave power and radiation time were evaluated by single factor and orthogonal experiments. The extraction conditions of flavones from Solidago canadensis by microwave-assisted method were optimized as 40：1 of the weight ratio of 50 % （V/V） ethanol to twigs and microwave power of 700 W for 20 min. Under the optimized conditions the relative standard deviation is 1.68 % （n=5） and the recovery is 97.6%-101.0%. Compared with soxhlet extrac- tion and ultresound-assisted extraction, microwave-assisted extraction was simple and accurate with good reproducibility. It is suitable for the determination of flavone in many kinds of traditional Chinese medicines.Compared with roots, stems, leaves and flowers, leaves contain more flavonoids.