Study On Extraction, Purification And Antioxidant Effects Of Total Flavonoids From Sweet Tea

Sweet tea is a good health tea, the total flavonoids is one of the main active ingredients of sweet tea.In this paper, the extraction,purification processes and antioxidant effect of total flavonoids from sweet tea were studied;the recovery process of total flavonoids were also researched meanwhile keep the original production of rubusoside unchanged.This studyprovides a theoretical basis for further development and use of total flavonoids of sweet tea, the recovery of total flavonoids not onlysaves precious natural resources, but also increased direct economic benefits.The results of this research are as follow:(1) Taking the yield of flavonoids asindicator, theoptimum extraction conditions of flavonoids in Sweet tea were investigated by singlefactor test andorthogonalexperiments. Theoptimum conditions were as follow: ethanol concentration 40%, ratio of material to liquid 1:20, extraction at 80℃ for 4 times.(2) Itwere comparedthattheabilityofadsorptionandseparationto Sweet tea flavonoidsof 11 differenttypeofmacroporousresins bymeansofstatic adsorptiontestanddynamic test. The results showedthatthetotalabilityof FL-3 resin was superior to the other macroporousresins, and conditionsinfluencingonthe processofseparationand purificationflavonoidswith FL-3 resin were investigated in detail, theoptimumabsorptionandseparation conditionwere as follow: concentration of sample 2.069 mg/m L ~ 3.104 mg/m L; 2BV/h adsorption velocity; 4.5times the volume of resin as sample volume; the best desorption conditions: Rinsing the resins with deionized water after completely adsorption to absterge Water soluble impurities,and then 40% ethanol and 4 times the volume of resin as eluent.The content of total flavonoids purified by FL-3 macroporous resin was up to 26.64%.(3) The recycling technology of flavonoids was explored meanwhile unchanging original production of rubusoside. The recovery conditions of flavonoids from Polyamide resin were studied, and finally 75%(v. v- 1) ethanol was selected as the desorption agent.Desorption solution was purified by FL- 3 resin, and the purity of flavonoids in the finalproductwas up to 62.70%, the recovery ratio was 1%.UV scans spectra and HPLC were used to analyze the final product and the sample contains rutin and quercetin.(4) In the study of anti-oxidative character of flavonoids of Sweet tea,the removal capacity of flavonoids compounds of Sweet teaon·OH and DPPH·were studied respectively, theresultshowedthat the purified and unpurifiedflavonoidscompounds in Sweet tea both have good oxidationresistance.