Study On The Extraction,Purification,Preparative Isolation And Antioxidant Activity Of Totle Flavones Of Hibiscus Manihot L. Flower

Hibiscus manihot L.is an annual herbage plant of malvaceous abelmosk.Hibiscusmanihot L. flower contains plenty of flavonoids.This paper studied on the extraction,purification,preparative isolation by HSCCC and antioxidant activity of totle flavones ofHibiscus manihot L.folwer. The results of the studies as following:1. This study was about extraction technology of flavonoids.Based on the signal factsexperiment,method of L₉（3⁴） orthogonal test was applied to optimize the extractionprocess.The optimum technological conditions were as following:60percent ethanol asextracting solvent,ratio of solvent to sample1:35（g/mL）,extracting during4h,and extractiontemperature90℃.Under this condition,the predicted result for the rate of flavonoidsextraction was38.67%.2.One of the twelve resins which has better purification effect on the flavones ofHibiscus manihot L. folwer was selected.Result shows that polyamide resin has betterpurification effect.The optimal technology parameters of polyamide were obtained:theconcentration of Hibiscus manihot L. folwer flavones solution was4.37mg/mL,and thesample liquid pH value was6.0,the added velocity was1.0mL/min,then flush with5BVwater,and the eluting solvent was80%alcohol,the flow rate of eluting solvent was1.0mL/min,the volume of eluting solvent was5BV.The purity of flavones in the purifiedproduct was72.6%, and it was increased1.9times.3. Constituted the HSCCC isolation methods of purified total flavones liquid of Hibiscusmanihot L. folwer.Through the comparisons among6kinds of solvent petroleum showed thatethyl acetate-methanol-water（10:0.4:10,v/v） was selected.The operation process were alsostudied.The follwing optimized parameters was obtained:coiled column rotation speed900rpm,flow rate2.0mL/min,temperature30℃. Under this conditions,the purity of hyperosideand puerarin from HSCCC were94.19%and94.58%,respectively.4. On the antioxidation activity studies at the concentration0.2-1.0mg/mL,theoxidationresistant abilities were as follows:the produits from HSCCC of hyperoside＞purified total flavones liquid＞comparison products Vc＞the produits from HSCCC ofpuerarin.In the DPPH methods, the produits from HSCCC of hyperoside contained 548.35mgVc/100g antioxidants,then the purified total flavones liquid with380.64mgVc/100gand the produits of puerarin from HSCCC with349.24mgVc/100g. In the FRAP methods,theproduits from HSCCC of hyperoside contained659.01mmolFeSO₄/100g,the purified totalflavones liquid with556.38mmolFeSO₄/100g,the comparison products Vc with465.88mmolFeSO₄/100g,and the produits from HSCCC of puerarin with339.24mmolFeSO₄/100g.