Study On Extraction And Purification Process, Structural Indentification And The Antioxidant Activity Of Flavonoids In Fig Leaves (Ficus Carica L.)

By using leaves of fig （Ficus carica Linn） as experimental materials, the ultrasoundassisted extraction （UAE） of total flavonoids was studied. Base on this, a single factorexperiment was invested. The technique environment for separating and purifying thetotal flavones of fig leaves by macroreticular adsorbents was evaluated andmacroreticular adsorbents resin which had a better performance of adsorption anddisadsorption effect was found out. The antioxidant abilities of fig leaves were alsodetected. At last the principal compounds of solutions of fig leaves was analyzed andidentified by HPLC-MS. THE results were as the followings:First of all, the ultrasound assisted extraction （UAE） of total flavonoid from theleaves of fig was studied in this paper. Second, to study the technique environment forseparating and purifying the total flavones from the leaves of fig by macroreticularadsorbents were studied. Third, the abilities of total flavonoid of fig leaves onscavenging hydroxyl radical （·OH）, superoxide anion radicals（O₂^-·）, and DPPHradicals and reduction capacity were detected. Fourth, analyzed and identified theprincipal compounds in all of solutions of fig by HPLC-MS.The results were as the followings：1, Ultrasonic extraction process of the total flavones was optimized with centralcomposite design-response surface methodology. In this experiment, the study foundoptimal process of extracting total flavonoid from fig leaves by ultrasonic. In themeanwhile, it told us how to reuse the fig leaves. Single factor experiments wereinvestigated: ultrasonic extraction time, ethanol concentration, liquid extraction ratethan that of the impact. Then，response surface methodology design was used todesign and evaluate the experiment. Practical examples showed that the extractionrate was3.48%under the optimum extracting conditions: ethanol35.48%, ratio ofsolid to liquid（w∶v）1∶59, ultrasonic power420W.2, Seven types of macroporous adsorption were evaluated for separating efficiencyby measuring the adsorption ratio, eluting ratio of total flavones. One of those had a good adsorptive effect. The results showed that D101macroporous adsorptive resinhad a better performance of adsorption and disadsorption in proper condition.Thereafter, adsorptive effect and separating effect by adsorption time, solutionconcentration, adsorption liquid pH value, stripping liquid pH value, the consumptionof eluant. The optimal purification condition of total flavonoid with macroporousresin was as follows: sample solution pH1, desorption agent were40%volumefraction pH3, volume to the resin weight12:1.3, Ethyl acetate extracts, n-butanol extracts and aqueous phase were used asmaterial. Antioxidations from extracts of different solvents are determined. Theresults showed that all extracts with different extraction solvents had scavengingeffects on superoxide anion radicals, hydroxyl radicals and DPPH radicals. All theextracts were reducibility. Along with extract density increased, scavenging effect andrestore ability were also strengthened. The relativity is preferable. Compared with Vc,the effect of three extracts on scavenging hydroxyl radicals is the same.4, The identification of constituents was performed by HPLC-ESI/MS. Sixflavonoid were obtained from preliminary purification samples. They wereapigenin-3-C-arabinose-6-C-glucoside, apigenin rutinoside, rutin, quercetin sixcarbon glycoside, kaempferol six carbon glycoside, kaempferol rutinoside.Apigenin-3-arabinose-6-glucoside, apigenin rutinoside, kaempferol six carbonglycoside are first reported in fig leaves.