目的:优选超声辅助提取宁夏枸杞叶总黄酮的提取工艺并测定其不同采收期总黄酮含量。方法:分别研究乙醇浓度,乙醇用量,超声时间,超声温度4个单因素对提取效果的影响,并设计正交试验,所得结果采用方差分析。利用优选出的最佳超声提取工艺测定比较不同采收期枸杞叶中的总黄酮含量。结果:确定了最佳单因素水平,通过正交试验优选出超声辅助提取枸杞叶总黄酮的最佳工艺条件为乙醇体积分数65%、乙醇用量1:60、超声提取时间35 min、超声温度70℃。结论:通过比较不同采收时期枸杞叶总黄酮的含量,结果为5月中旬含量最高。 OBJECTIVE: To optimize the extraction technology of total flavonoids from Lycium barbarum L. by ultrasonic assisted extraction and determine the content of total flavonoids in different harvest time. Methods: The effects of ethanol concentration, ethanol dosage, ultrasonic time and ultrasonic temperature on the extraction efficiency were studied respectively. Orthogonal experiments were designed and the results were analyzed by variance analysis. The best ultrasonic extraction process was used to determine the content of total flavonoids in leaves of Lycium barbarum at different harvest time. Results: The optimal single-factor level was determined. The optimum conditions of ultrasound-assisted extraction of total flavonoids from Lycium barbarum leaves by orthogonal test were as follows: ethanol volume fraction 65%, ethanol 1:60, ultrasonic extraction time 35 min, ultrasonic temperature 70 ℃. Conclusion: By comparing the content of total flavonoids in Lycium barbarum leaves in different harvest time, the content of Lycium barbarum leaves is the highest in mid-May.