Study On The Antidiabetic Constituents And Quality Control System Of Tithonia Diversifolia (Hemsl.) A. Gray

Tithonia diversifolia (Hems1.) A. Gray, a 2~5 m tall perennial shrub, grows natively in Mexico and also distributes in parts of Africa, Asia, North America and Australia which is used for ornamental purposes or as manure for farming. It is naturalized in tropical, southern and central sub-tropical regions in Yunnan, China. Its had been used as a traditional treatment for diarrhea, feverhematomas, hepatitis, hepatomas, malaria and wounds.This dissertation describes the chemical and pharmacology study of this plant. 80% ethanol extraction of the herb, collected in Mengzi of Yunnan province, was partitioned into five fractions as petroleum ether, dichlormethane, acetic ether, n-butanol and water portion. Guided with initial pharmacological actives test on animal model of typeⅡdiabetes, the crude extraction and dichlormethane fraction were shown to have obviously activity on reduced serum glucose levels and improved glucose tolerance. Petroleum ether and acetic ether fraction have a temparate antidiabetic activity .. Nine compounds were obtained from dichlormethanel extract, the active part. By a variety of chromatography methods, their structures were established on the basis of spectral data including UV, IR, EI-MS, ESI-MS, 1D-NMR, 2D-NMR, physical and chemical properties as follows: TD-1:β-sitosterol; TD-2: 2, 2-dimethy-6-acetyl -8-hydroxy-2H-chromen; TD-3: 6-methoxyl-Apigenin; TD-4: Tagitinin A; TD-5: Daucosterol; TD-6: TithonianⅠ; TD-7: 6-methoxyl-luteolin; TD-8: 5, 6, 9-trihy droxyl-10-(E)-octadecenoic acid; TD-9: Tithoniamide B.The chemical investigation of petroleum ether , acetic ether and n-butanol fraction of this plant resulted in the isolation of 12 compounds and 10 structures of them were determinated as follows:TD-10: Isoselachoceric acid , TD-11: 6(E)- octacosaene acid, TD-12: Nonyl decanoate; TD-13: Docosanoic acid; TD-14: 2, 2-dimethy-6-acetyl -7-hydroxy -2H-chromen; TD-15: 6, 7, 3`, 4`- tetrahydroxyl flavone; TD-16: 2, 2-dimethy-6-acetyl-2H-chromen-8-O-β-D-glucoside; TD-17: 2, 2-dimethy-6-acety -2H-chromen; TD-18: 2, 2-dimethy-6-acetyl-7-methoxy-2H -chromen; TD-19: 2, 4-muconic acid.Among all the compounds mentioned above, TD-6 is new compound and TD-8, TD-12, TD-15, TD-16, TD-19 are isolated from this plant for the first time. Seven samples of this herb from different areas of Yunnan were collected. The appearance characteristics of different samples of Tithonia diversifolia were almost similar. The microscopic features of different samples leaves were found to exhibit typical characters of dicotyledon, the common characters may be showed among varied parts of leaves except the numbers and disposed styles of conducting bundles in it. The microscopic features of stems and petioles were not showed obviously different.In order to consummate the quality control system, based on the pharmacodynamic action test, LC-MS/MS method for determined quality of different samples of Tithonia diversifolia was established. 5 compounds of dichlormethane extract were used as marker substance. Therefore we have developed a simple, precise and reproducible method for the detection and quantification of these compounds in the medicinal material. The result indicated that the material grew in Simao of Yunnan province is the best.