Studies On Chemical Constituents And Antitumor Activitives Of The Bark Of Voacanga Africana Staph

This dissertation consists of four chapters,mainly focus on the chemical constituents and antitumor activities of the bark of Voacanga africana Staph. The chapter one is the research on chemical compositions of the bark of Voacanga africana Staph. The chapter two is the research on simultaneous determination of the content of three alkaloids active ingredients in the bark of Voacanga africana Staph.The chapter three is the research on antitumor activities of alkaloid compounds of Voacanga africana Staph. The chapter four reviews the recent chemical and pharmacological research progress on Voacanga africana Staph.Voacanga africana Staph. belongs to genus Voacanga (Apocynaceae). Overseas studies show that it has good bioactivity in the aspect of drμg withdrawal,curing Alzheimer disease, anti-malaria and so on.In preliminary study on cytotoxic activity in vitro, the non-small cell lung cancer A549cells proliferation in vitro for alcohol extraction of Voacanga africana Staph.was evaluated by MTT method. It’s found that the extraction of Voacanga africana Staph. has significant antitumor activity.This dissertation adopted the modern systematic technology of separation combined with spectroscopy methods, and the chemical constituents of the plan t were studied.22compounds were isolated from the ethyl acetate extraction o f Voacanga africana Staph. and18compound^were identified by the spectrosc opic methods and physicochemical property. Their structures were identified as3-OAc,△7,bauerenylacetate(1),β-sitosterol(2),voacangine(3),8-hydroxy-6-methoxy-3-pentylisocoumarin(4),voacristine(5),voacamine(6),22E,24R-5α,8a-epidioxyergosta-6,22-dien-3p-acetate(7),voacristinehydroxyindolenine(8),voacryptine(9),oleanolicacid (10)β-amyrin(11),(22E)-5a,8a-epidioxyergosta-6,22-dien-3β-ol(12),6p-hydroxystigma st-4-en-3-one(13),palmiti acid(14), stigmast-5-en-3p,7a-diol(15), stigmast-5-en-3p,7p-diol(16),lichenxanthone (17),betulinic acid(18). Except compound2,3,5,6,8,9,the other compounds are isolated from this plant for the first time; Compound1,4,7,12,13were isolated from this genus Voacanga for the first time;Compound4is the frist coumarins isolated from the species Voacanga africana Staph.Domestic and international research shows that alkaloids are the main active ingredient of Voacanga africana Staph. voacristine voacangine and voacamine are the major alkaloids, all belong to the indole alkaloids, which has good antiumor activity. Based on the above background, this experiment use high performance liquid chromatography to the determine three main alkaloid content of active ingredients. The chromatographic conditions as the follows:Kromasil C18column(250mm×4.6mm,5um),with Methanol-O.lmol/L ammonium acetate mobile phase,gradient elute.the flow rate was1.0mlmin, the column temperature was30℃,The detection wavelength was at286nm.The results show that voacristine voacangine and voacamine in Voacanga africana Staph.can get a baseline separation.There was a good linear relationship between voacristine voacangine and voacamine within the rangeof1.03～7.21μg(r=0.9992),0.79～5.53μg(r=0.9993)and3.34～23.38μg(r=0.9991).T he recoveries(n=6) for voacristine voacangine and voacamine were98.20%、97.07%、98.42%respectively. The method was simple,accurate,separable and repeatable,and applicable for determination of voacristine voacangine and voacamine in Voacanga africana Staph.In addition, Antitumor activity studies upon11indole alkaloids monomer component(voacamine,voacangine, voacristine,19-epi-voacrstine,19-epi-heyneanine,v oacangine-hydroxyindolenine, voacristine-hydroxyindolenine,epi-ibogaine,tabersoni ne,voacryptine,vobasine)isolated from Voacanga africana Staph. anti-tumor activity in vitro screening results by using MTT show that in addition to the two compounds(voacristine、voacristine-hydroxyindolenine), in fact, the others are have different levels of activity on the A549, DU145, H1975, LNCAP, MV4-11, PC-9, THP-1, PC-9, Raji, U87, U266tumor cell strains. especially voacamine almost exhibited good inhibitory activity on11cell lines. This not only lay the foundation for the further study of pharmacological activity, but also drμg provides an important theoretical reference for the study of new anti-cancer...