The Study On Extraction,Purification And Anti-oxidative Character Of Total Polyphenols From Polygonum Capitatum

Polygonum capitatum as the main material,the determination method of total polyphenols in Polygonum capitatium,the extraction conditions of total polyphenols from Polygonum capitatum by response surface method,purification process of total polyphenols of Polygonum capitatum,and antioxidant effect were studied.The main conclusions were as follows:(1)To set up an assay method for the determination of total polyphenol in Polygonum capitatum,the suitable determination conditions of total polyphenol content in Polygonum capitatum by Folin-Ciocalteu Colorimetry were investigated using gallic acid as standard.The results indicated when Folin-Ciocalteu reagent was 2.5ml and 12% sodium carbonate solution was 7mL,reaction 40 min at 35?,there was a good linearity between the absorbance and gallic acid concentration in 760 nm,the average recovery was 98.92 % and RSD was 0.45% ? This method was simple,accurate,repeatable and stable.It can be used for the determination of total polyphenol content in Polygonum capitatum(2)Extract condition of total polyphenol were optimized by single factor response surface method.The results showed that the optimal extraction conditions were as follows: ethanol concentration 57.19%,reflux temperature 80?,reflux time 2h,and ratio of liquid to solid 25 ml/g.Under those conditions,total polyphenol in Polygonum capitatum extraction rate was 4.43%.(3)10 types of macroporous resins were tested by static adsorption and desorption experiments for purifing polyphenols in Polygogum captitatum and purifying conditions by the best resin were investigated.The results showed that HPD-722 was the best resin.Purifying conditions were as follows: concentration of adcorption sample 2.0~4.5 mg/mL,2 BV/h adsoption velocity,7.5 BV 50% ethanol solution as eluent,the content of the total polyphenol sample was up to 59.02%.(4)The purified polyphenols were extracted by different polar solvents and contenes of polyphenols were measured in various parts.Activitions on scavenging ABTS free radicals,DPPH free radicals,and OH radicals were studied.Results showed that different polar extracts of Polygonum capitatum polyphenols had higher scavenging abitities on free radicals,dose effect relationship between the mass concentration of polyphenols and activity was good.The highest activity on scavenging the OH free radicals,DPPH free radicals and ABTS free radicals was the ethyl acetate section with higher content of total polyphenols.The one of main antioxidant ingredients in ethyl acetate section was quercitrin by HPLC...