大黄甘草汤中甘草酸对蒽醌类化合物提取率的影响

Effect of Glycyrrhetinic Acid on Extraction Rate of Anthraquinoids in Dahuanggancao Decoction

目的研究大黄甘草汤中甘草酸对大黄中游离与结合蒽醌类化合物提取率的影响,揭示甘草在中药方剂配伍中能缓和大黄泻下作用的原因。方法按传统水煎法制备大黄甘草汤,分光光度法测定提取液中游离与结合蒽醌类化合物的含量。结果大黄与甘草在水煎过程中,甘草中的甘草酸可增加大黄中游离蒽醌的提取率,降低大黄中结合蒽醌的提取率。结论大黄与甘草在煎煮过程中,甘草中的甘草酸与产生泻下作用的结合蒽醌生成沉淀,降低了结合蒽醌的含量,甘草可缓和大黄的泻下作用。

Objective To study the effect of glycyrrhizic acid on the extraction rate of anthraquinonoids from Dahuanggancao decoction and to elucidate the reasons for Radix Glycyrrhiza to moderate the purgative effects of Rhubarb during compatible use of Chinese traditional medicine. Methods The Dahuangganeao decoction was prepared following the traditional ways and the contents of the free anthraquinones and conjugated anthraquinones of the crude extraction were measured by Speetrophotometer. Results During the decocting of Dahuangganeao decoction, glycyrrhizie acid from Radix Glycyrrhiza could increase the extraction rate of free anthraquinones and glycyrrhizie acid could also precipitate conjugated anthraquinones. Conclusion During boiling Glycyrrhiza and Rhubarb with water, glycyrrhizic acid from Radix Glycyrrhiza can precipitate conjugated anthraquinones, which is the main component with purgative activity of Dahuangancao decoction. Thus, the decrease of conjugated anthraquinones content may be the reason for Radix Glycyrrhiza to moderate the purgative effects of Rhubarb.