With ultrasonic technology,tannin was extracted from persimmon leaf marinated in 70% acetone solutions.The effects of ultrasonic power,extraction temperatures and times on yield of tannin were studied.A quadratic regression models was applied to analyze results of experiment.It showed that amount of tannin extracted was 203.15 mg/g as the extraction temperature was 52 ℃,the ultrasonic power was 80 W and the extraction time was 42 min,which yield is more than one of ...