| Angelica Keiskei is a plant enriching in flavonoids,coumari,g ermanium,vitamin B12,and other active ingredients which can be u sed as food and medicine.It was commonly used in clinical treatm ent of urinary and constipation.In this paper,the extraction and pu rification of the main active ingredient-flavonoids in angelica keis kei were studied.Then flavonoids were separated and Structures we re identified.Finally the antioxidant activity of flavonoids were stud ied.The results can provide theoretical references for the developm ent and application of the angelica keiskei.The results of this research were as follow:(1)Taking the extraction rate of flavonoids as indicator,The effects of ethanol volume fraction,extraction temperature,ratio of material to liquid and extraction time on the extraction rate of flavonoids w ere investigated by single factor experiment.Using Box-Behnken desi gn response surface,the extraction conditions of flavonoids from an gelica keiskei were optimized,The optimal extraction conditions were as follow: ethanol concentration 53%(v.v-1),ratio of liquid to mater ial 17:1,extraction temperature 82?,extraction time 2h for 2 time.(2)Taking the adsorption rate and desorption rate as indicators,12 t ypes of macroporous resins were tested by Static and dynamic adso rption and desorption experiments for purifying flavonoids from An gelica keiskei,and purifying conditions by the best resin were inves tigated.The results showed that: HPD-600 was the best resin.adsor ption conditions were as follows: 3BV/h adsorption velocity,concen tration of sample 2 mg/m L~3 mg/m L,2.7 times volume of resin a s sample volume;desorption conditions were as follows: 50% ethan ol,4 times volume of resin as eluent.the content of flavonoids pur ified with HPD-600 macroporous resin was improved from 4.46% t o 36.96%.(3)In order to compare antioxidant activity of different polar fracti ons of extracts from angelica keiskei,Crude Extracts from Angelica Keiskei was adsorbed by HPD-600 macroporous resin.and 50% eth anol eluant was collected as product.The product were separated int o three subfractions(ethyl acetate fraction,n-butanol fraction and aq ueous fraction)by organic solvents of different polarities based on l iquids-liquids extracting method.The contents of total flavonoid of different fractions were determined.Meanwhile,the activities on sca venging DPPH,ABTS+ radical,ferric-reducing power were also stud ied.The results showed that the ethyl acetate-soluble fraction had t he strongest antioxidant activity,with higher content of total flavon oid.(4)Using medium pressure column chromatography and high perform ance liquid chromatography separation method,two compounds were isolated from ethyl acetate fraction and their structures were elucida ted by spectral analysis such as 1H-NMR,13C-NMR,ESI-MS.Acco rding to literature spectral data,two compounds were identified as quercetin-3-O-?-D-glucopyranside and luteolin-7-O-?-D-glucpyranosid e.Then the antioxidant activities of the compounds were measured,The results showed that both compounds had stronger antioxidant a ctivities. |
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