Optimization of ultrasonic- assisted extraction of cucurbitacin B from watermelon( Citrullus colocynthis) vine

Cucurbitacin B was extracted from watermelon( Citrullus colocynthis) vines by the ultrasonic- assisted extraction.The ultrasonic- assisted extraction was optimized by the combination of the single- factor experiment and response surface methodology.The results showed that the ultrasonic temperature was the key factor affecting the cucurbitacin B extraction rate,while the ethanol concentration and ultrasonic time showed less influence on the extraction rate.The extraction rate of the cucurbitactin B reached to 84.7% when the ethanol concentration was 75%with the ultrasonic temperature of 80 ℃ for 30 min.