Antioxidant activity of ultrasonic extraction isolates from three gorges reservoir area Juglans regia of Wu walnut

The total saponins were examined in the dissepiment of Wu walnut. On the basis of single factor experiments with the method of ultrasonic-assisted extraction,optimal parameters of extraction process was researched by using response surface method. A mathematical model including material/liquid ratio,ultrasonic treatment time and extraction temperature was created. By typicality analysis,the optimum process conditions were as follows:the ultrasonic treatment time was 96 s,the ultrasonic power was 300 W and the material/liquid ratio was 1∶33(g/m L). Under such conditions,an optimal total saponins yield of 5.98% was obtained. Saponins displayed strong antioxidant effect and scavenging capacity against DPPH,ABTS radical,and more strengthen with the increase in the concentration of total crude saponins extract.