Optimization of ultrasonic asssisted extraction of phytosterol from Paeonia suffruticosa Pericarp

The ultrasonic method was used to extract the phytosterol from Paeonia suffruticosa pericarp. The ultrasonic power,the ratio of liquid to solid and the ultrasonic extraction time were assessed. A three-factor three-level orthogonal test was applied to optimize the ultrasonic extraction conditions. The results showed that the yield of phytosterol 0.495%±0.001% extracted with the optimal extraction conditions:ultrasonic power 300 W,liquid to solid ratio 30 mL/g and ultrasonic time 60 min was significant higher than the yield of phytosterol 0.439%±0.004% with the ethanol extraction conditions(p<0.05).