RESUMEN
Objective To establish a suitable extraction and purification process line for industrial production of liquiritin. Methods With the extraction rate of liquiritin as index, orthogonal test was used to determine the optimum conditions; with the retention rate of liquiritin and impurity removal rate as the indexes, orthogonal test was used to optimize the best ultrafiltration process parameters. Results The optimum extraction conditions were: 24 times 0.75%ammonia water, extracted three times, each time under 60 min. The liquiritin average extraction rate was 72.3%. The best ultrafiltration process parameters were: 10 nm inorganic ceramic membrane, pressure of 0.12 MPa, temperature of 25 ℃. The liquiritin average retention rate was 98.9%, and the average removal rate of impurity was 23.3%. Conclusion This process has low production cost and good safety, and is suitable for industrial application.