Study on Technology of Extracting Total Flavones from Persimmon Leaves by Ultrasonic Wave

The purpose was to study the technology of extracting total flavones from Persimmon leaves by ultrasonic wave.Total flavones were extracted from Persimmon leaves by ultrasonic wave.The optimum technology was ascertained through single factor and orthogonal experiments.The extraction rate of total flavones from Persimmon leaves was increased along with the increment of ethanol concentration.The extraction rate was reduced after the ethanol concentration exceeded 60%.The extraction rate of total flavones was rapidly increased along with the increment of the ratio of material to liquid.The increasing amplitude was obviously slowed when the ratio of material to liquid reached 1∶20.The extraction rate of total flavones was increased along with the increment of ultrasonic extracting time,but the trend was not obvious.The order of factors that affected the extraction rate of total flavones from Persimmon leaves was the ratio of material to liquid extraction time ethanol concentration.The optimum extraction technology was as follows: ethanol concentration of 60%,ultrasonic extracting time of 45 min,ratio of material to liquid of 1∶25,under which the extraction rate yield of total flavones was 3.54%.Compared with conventional refluxing method,the yield of total flavones from Persimmon leaves by ultrasonic wave was enhanced by 77%.And this method shortened the extraction time and reduced the dosage of extraction solvent.Ultrasonic wave extraction method had obvious advantages of high extraction efficiency and low cost.