Study On Separation And Hypouricemic Action Of Total Flavonoids From Toona Sinensis Leaves

Toona sinensis(T.sinensis) belongs to the family of Meliaceae,the Genus of Toona,is a kind of perennial and woody plant.It was also an endemic plant of China and had long planting history,which with hi-nutritive value and health functions.Its potential market is huge and developable foreground is very vast.This thesis draws up the extracting, purification and activities of substance in Toona sinensis.The total flavonoids content of the Toona sinensis leaves was determined.It was concluded that there were differences upon the contents of the flavonoids of different locations and the highest content was from Zhengzhou.The content of flavonoids changed as the seasons changed and it had the highest content in octobe.Response surface analysis was used to determine the optimized conditions for the microwave assisted extraction of total flavonoids from the Toona sinensis leaves.The results showed that the optimized conditions were extraction time 85s,ratio of solvent to material 20mL/g,ethanol volume fraction 50%,microwave power 700W,twice for extraction,and the yield of total flavonoids was 2.39%.The parameters of the optimal water extracting technology for the total flavonoids were that the ratio of sample to extracting solution was 15mL/g,1 hour of extracting time,twice for extraction after the single-factor experiments and orthogonal experiments were finished.The purification technology of Toona sinensis flavonoids by means of absorbent resin chromatography and solvent extraction were also studied in this paper.The total flavonoids purity of extraction B purified by adsorption chromatography,reached 49.24%,which was 54.04%higher than that before purification.It also showed that the ethyl acetate is the best solvent to extract flavonoids,which can enrich them to a high purity of 71.42%.The results of TLC,HPLC,LC/MS/MS showed that the strong antioxidant capacity was based on four kinds of flavonoids with relative molecular weight of 578,464,448 and 432.The xanthine oxidase(XO) inhibitory activity in vitro was assayed spectrophotometrically at 295 nm.The results show that the extraction C possessed significant inhibitory action on XO activity in vitro,and its IC50 value was 56.91μg/mL. The dose-effect relation was also observed.The uricase inhibitor potassium oxonate was used to induce hyperuricemia in mice and the mice were then treated with oral extraction for 7 d.And the serum uric acid(SUA) level was determined with phosphotungstic acid method.It showed that at the dose of 100,200 mg/kg,the SUA levels of hyperuricemic mice were decreased significantly(p＜0.001),when compared to hyperuricemic control,and not different from normal mice.