Abstract: The optimal extraction condition of arctiin was studied by ultrasonic method. The newly fresh seed of the Arctium lappa was used to investigate the effects of the ultrasonic power, ultrasonic time, ultrasonic temperature, solid-liquid ratio and other factors on the extraction rate of arctiin. Orthogonal experiment was performed to optimize the extraction conditions. The results showed that the crush size was 100 mesh, extraction solvent was 95% ethanol, pre-soaking time was 2 h, material liquid ratio was 1∶150 (g∶mL), ultrasonic time was 45 min, ultrasonic power was 114 W, ultrasonic temperature was 70 ℃ as the optimum extraction conditions. The three parallel tests were carried out under the optimum extraction conditions, the average extraction rate obtained for arctiin was 12.69% . Compared with other ultrasonic extraction process, arctiin yield was increased at least 1.89%.

Key words: the seeds of the Arctium lappa, arctiin, content determination