从挥发性成分的动态变化规律探索银翘散“香气大出即取服”的科学内涵

Scientific connotation of decocting method “taking when fragrance volatilized fiercely” for Yinqiao Powder based on dynamic changes of volatile components during decocting process

目的 建立银翘散蒸馏液中3种主要挥发性成分薄荷酮、薄荷脑、胡薄荷酮的定量测定方法,探索银翘散煎煮过程挥发性成分的蒸发规律,为阐明银翘散“香气大出即取服”的科学内涵提供科学依据。方法 收集不同煎煮时间段的银翘散蒸馏液,采用GC-MS法定性分析其中挥发性化学成分并测定薄荷酮、薄荷脑、胡薄荷酮的量,考察不同煎煮时间对银翘散中薄荷酮、薄荷脑、胡薄荷酮蒸发速度的影响。结果 银翘散挥发油GC-MS总离子流色谱图共确定色谱峰26个,其中相对质量分数大于1.5%的色谱峰14个,主要来源于连翘、薄荷、荆芥3味药;随着煎煮时间的延长,相对质量分数较大的3种成分薄荷酮、薄荷脑、胡薄荷酮的蒸发速度均先增大后逐渐减小,平均蒸发速度均在5~10 min达到最大值,分别为13.77、147.74、31.26μg/min;煮沸0~5、5~10、10~15、15~20、20~25、25~30、30~40、40~50、50~60、60~80、80~100、100~120 min时间段,银翘散中薄荷酮、薄荷脑、胡薄荷酮3种成分总的平均蒸发速度分别为160.23、192.77、120.71、70.85、54.01、42.41、30.36、17.87、14.98、10.01、7.79、7.58μg/min。结论 煎煮时间对银翘散挥发性成分蒸发速度影响较大;煮沸约5 min时,香气大出,煮沸5~10 min时间段,银翘散中3种挥发性成分的平均蒸发速度也最大,散失也最快;煮沸15 min后,香气变淡,银翘散中3种挥发性成分蒸发速度明显减小,提示银翘散“香气大出即取服”传统煎煮方法具有一定的科学依据。

Objective To establish a method for the determination of three main volatile components （menthone, menthol, and pulegone） in Yinqiao Powder （YQP） distillate and provide the evidence for elucidating the scientific connotation of its traditional decocting method ＂taking when the fragrance volatilized fiercely＂. Methods YQP distillates with different decocting time were prepared to study the dynamic changes of chemical components during decocting process. GC-MS was used to analyze the volatile components qualitatively and determine the contents ofmenthone, menthol, and pulegone in YQP distillate. Results GC-MS total ion chromatograms of YQP volatile oil included 26 peaks, of which the relative contents of 14 peaks were greater than 1.5%, mainly from Forsythiae Fructus, Menthae Haplocalycis Herba, and Schizonepetae Herba. With the extension of the boiling time, the evaporation rates of menthone, menthol, and pulegone all increased to maximum and then decreased gradually. When boiling for 5--10 min, the maximum average evaporation rates ofmenthone, menthol, and pulegone were 13.77, 147.74, and 31.26 ig/min, respectively. When boiling for 0--5, 5--10, 10--15, 15--20, 20--25, 25--30, 30~0, 40--50, 50~0, 60--80, 80--100, and 100--120 min, the average evaporation rates of total three volatile components were 160.23, 192.77, 120.71, 70.85, 54.01, 42.41, 30.36, 17.87, 14.98, 10.01, 7.79, and 7.58 ig/min, respectively. Conclusion The evaporation rates of menthone, menthol, and pulegone in YQP are heavily influenced by decocting time. The fragrance is volatilized fiercely at about 5 min after boiling, while the average evaporation rates ofmenthone, menthol, and pulegone are high, so after boiling for 5--10 min, menthone, menthol, and pulegone were evaporated a lot. The fragrance gets weak after 15 min of boiling, the average evaporation rates ofmenthone, menthol, and pulegone are decreasing heavily. It is suggested that the traditional decocting method has some scientific foundation.