Study On Chemical Constituents And Anti—diabetic Activities Of Bougainvillea Glabra And Afzelia Xylocarpa

Diabetes is the world’s largest endocrine disease, which is characterized by elevated blood glucose production and impaired glucose clearance. However, clinical available drugs for type 2 diabetes have a number of limitations, such as adverse effects and rates of secondary failure. Therefore, it is necessary to look for new drugs and interventions that can be used to manage this metabolic disorder.Bougainvillea glabra and Afzelia xylocarpa are used as anti-diabetic herbals in domestic and oversea researches, but studies on the chemical and bioactive constituents from Bougainvillea glabra and Afzelia xylocarpa are rare and plain. The main chemical constituents of these plants are little and simple, as flavonoids, the anti-diabetic activity need more research. This article presents an overview on main chemical constituents and pharmacological effects of these plants in domestic and oversea researches, so as to provide a basic scientific evidence for its conservation and sustainable utilization.This thesis chooses Bougainvillea glabra and Afzelia xylocarpa as research object, aiming to study the anti-diabetic effect of an active component group from active components of Bougaira and Afzelia xylocarpa through relevant experiments and to determine new hypoglycemic components. Then, we research their mechanism of lowering blood preliminarily and provide scientific theory basis for the clinical application of Bougainvillea glabra and Afzelia xylocarpa.The chemical constituents are separated and purified from Bougainvillea glabra by means of multiple chromatographic technique(silsca gel, Sephadex LH-20, ODS, HPLC, MCI); their structures are identified by spectra methods of MS, NMR, IR, UV, and so on. 20 compounds are obtained from the plant and among which 14 compounds have been identified: oleanolic acid(1), oleanolicacid-3-O-β-D-(6’-methylester)-glucuronopyranoside(2), β-daucosterol(3), araloside A methylester(4), chikusetsusaponinⅣa methylester(5),3-O-[β-D-xylopyranosyl(1→3)β-D-methylglucuronopyran oxylate]oleanolic acid(6), phytol(7), 24-methylenecycloartan-3-ol(8), 3β-Hydroxy-5α,8α-epidioxyergosta-6,22-diene(9), spinasterol(10), stigmasterol(11), friedelin(12), palmitic acid(13), β-sitosterol(14). Thereinto compounds 1-6, compounds 8、9, compounds 11、12、14 are found from the genus Bougainvillea for the first time. All compounds except compounds 1、2 and 6 are assayed for their anti-diabetic activity in the model GLUT4, other compounds show no anti-diabetic activity. Experimental results indicates that the methanol, petroleum ether, ethyl acetate phase during extraction process of the barks of Bougainvillea glabra exhibited insulin-sensitizing activity after 20 hours on the concentration of 10 μg/ml, the insulin-sensitizing activities of the petroleum ether, ethyl acetate phase are better. The present study found that the extracts from Bougainvillea glabra have the anti-diabetic effect in type diabetic mice Ⅱ through relevant experiments.The chemical constituents are separated and purified from Afzelia xylocarpa by means of multiple chromatographic technique(silsca gel, Sephadex LH-20, ODS, HPLC, MCI); their structures are identified by spectra methods of MS, NMR, IR, UV and so on. 18 compounds are obtained from Afzelia xylocarpa, among which 11 compounds have been identified:(3S,5R,6R,7E,9S)-megastigman-7-ene-3,5,6,9-tetraol(1),(3S,5R,6R,7E)-3,5,6-trihydroxy-7-megastigmen-9-one(2), kaempferol-7-O-β-D-glucopyranoside(3), oroxylin A-7-O-β-D-glucuronide(4), epifriedelanol(5), friedelin(6), stigmasta-4,25-dien-3-one(7), stigmasterol(8), β-sitosterol(9), butyl benzoate(10), palmitic acid(11). Thereinto compounds 1-2, compounds 4-11 are found from the genus Afzelia Smith for the first time, all compounds are showed no anti-diabetic activity.