Background: To develop the optimal extractive technique of the Radix glycyrrhizae and Angelica dahurica (Fisch.) Benth.et Hook in the Fengshiding dropping pill. Methods: Single factor experiments were carried out on the effect of water-ethanol extraction by the multiple guidelines grading of the dried extract quantity, the contents of liquiritin and imperatorin. Furthermore, orthogonal experimental design was used for the optimization of cross-functional process. The dried extract quantity and the contents of liquiritin and imperatorin were used as targets. The interaction among solid-liquid ratio, ethanol concentration, extraction time and extraction times was investigated by the analysis of variance. Data processing was carried out with the multiple guidelines grading method for optimizing the extraction condition. Results: The optimal extracting condition was founded to be successively 3 decoctions with 12 times of 75% alcohol for 1 h. Conclusion: The optimal process is stable and feasible.
Key words: Radix glycyrrhizae, Angelica dahurica (Fisch.) Benth.et Hook, Liquiritin, Imperatorin, Orthogonal test.