Studies On Extraction,Purification And Identification Of Polyphenols From Persimmons' Leaves

In this paper, the technological conditions of extraction and purification of polyphenols from persimmon was studied.Then polyphenols were proved by color reaction and HPLC.Firstly,using spectrophotometry plotted the standard curve of polyphenols. the regression equation was y=82.495x+0.0108,r2=0.9991.Determining the content of polyphenols in persimmon during different times,results indicated persimmon in May had the highest content,and using the persimmon in May was more reasonable for extraction.Then,the paper studied the extraction technology of persimmon'polyphenols with ultrasonic wave extraction for the first time. From the orthogonal results of ultrasonic wave extraction,the optimal conditions of extraction polyphenol compounds are as follows:extracting with 40% ethanol solution,ratio of raw materials and solution was 1:40,temperature at 50℃extracting 20min.The yield of total polyphenol is 5.69% under the optimal conditions.At last,the purification of polyphenols was studied after extracting polyphenols from persimmon. Conclusion:The optimum conditions is:AB-8 type macroporous resin,concentration of polyphenols of sample is 2.67mg/ml and current velocity of 2ml/min, pH value of sample is 5. eluted to non-sugar by distilled water after adsorption saturation, and then 70% ethanol elution that the optimum elution speed was 1.5ml/min, and the quantity of elution solvent was 250mL,in the end,33.64% the purification of polyphenol was obtained.Finally, the product contain polyphenols by color reaction and HPLC.