[Multi-index determination and optimization of liquirtin separated from polyamide resin]

To optimize the separation process of liquirtin from glycyrrhiz by static, dynamic adsorption and desorption experiments on polyamide resin, with liquirtin, isoliquiritin and glycyrrhizic acid as the study index. The optimum process conditions were that the pH of solution was regulated to be 7.0, the concentration of liquirtin was 1.296 g x L(-1), the volume of loading buffer was 3 BV. After absorption, efforts shall be made to elute resin with water, 10%, 20%, 30% ethanol (3 BV for each), collect 20% ethanol eluted fraction, and recover solvents. The results showed lower contents of such impurities as isoliquiritin and isoliquiritin in extracts sepaprated under this process conditions, as well as an increase in purity of liquirtin from 4.86% to 88.5%. The method was simple and feasible, it could obtain a higher purity in extracts from liquirtin and provide basis for industrialized separation and preparation of liquirtin.