Microwave-Assisted Extraction Of Useful-Component From Liquorice And Comprehensive Utilization Of Glycyrrhiza

The purpose of this study was to develop an efficient process for isolation and purification of the useful-component from liquorice. Microwave-assisted extraction (MAE) method was studied for the extraction of glycyrrhizic acid (GA) and licoflavones from the roots of Glycyrrhiza species. And through the refining process, GA and licoflavones can be got separately.On base of studying of the other people, the methods of analyzing GA by HPLC and licoflavones by spectrophotomer were founded.Several factors, such as extraction solvent, time, liquid/solid ratios materials size and microwave power, which were effected MAE operation were investigated by single factor experiments and orthogonal experiments And the optimal conditions were obtained from the experiments. The optimum conditions of MAE is10min extracting in70%ethanol water solvent at60℃under the microwave heating, microwave power350W, and the liquid/solid ratios of25:1(mL/g). Under this condition, we can both extract glycyrrhizic acid (GA) and licoflavones efficiently. The extracting percentage of GA was3.81%, and the licoflavones was4.40%. Comparing with other traditional methods, such as hot reflux extraction and soxhlet extraction, MAE method is fast, efficient and energy saving, which is recommendable to the application to useful-component extraction form the Chinese traditional medicine.To separate GA and licoflavones only used some easy steps, for example, solvent extraction, pH value adjustment. Based on the results of orthogonal design, the best refining procedure is as follows:95%ethanol water solvent, pH=3-4, temperature40℃, time4h. At last, the colorless monoammonium glycyrrhizinate crystal with purity of96%and licoflavones with the content of40%were got.