Study On Chemical Constituents Of Processed Gentiana Rigescens Franch.ex.Hemsl.

Gentiana rigescens Franch.Ex.Hemsl.is a perennial herb of Gentianaceae,most of which is wildlife and mainly produced in Yunnan province,is one of the Gentiana scarbra recorded in Pharmacopeia of the People's Republic of China.It is the traditional Chinese medicine materials used to clear heat,eliminate dampness and discharg fire from Liver and gallbladder.Modern pharmacological studies have found that the main active constituents are iridoid terpenoids,in which gentiopicroside is the highest.The chemical composition of medicinal materials will change due to the influence of heating or excipients during processing.Because of the influence of acetal structure and heating or excipients during the processing,the chemical composition of iridoid compounds will change.At present,the reports on G.rigescens are mainly focused on the study of the chemical constituents and pharmacological activities of the raw materials,and there is no systematic study on the transformation of the substances after the processing and the transformation laws.The purpose of this study is to discuss the changes of the main components in the processing process of the G.rigescens and the analyze of its chemical composition after processing.The thesis consists of the following four chapters.In the first chapter,the chemical constituents,pharmacological effects and processing of G.rigescens were reviewed.In the second chapter,based on the change of the material basis before and after the processing of G.rigescens,the method of processing steaming for 34 hours under the condition of 120 °C is optimized by the simulation method.Then,the contents of gentiopicroside and swertiamarin were determined by the method of decocting water,sampling at intervals,and the content changes of gentiopicroside and swertiamarin were determined by HPLC.The results showed that the contents of gentiopicroside and swertiamarin decreased obviously with the prolongation of heating time,and the quantitative changes of gentiopicroside and swertiamarin in G.rigescens were clarified.In the third chapter,by using silica gel column chromatography,MCI column chromatography,preparation type thin-layer chromatography,ODS reversed-phase column chromatography,Sephadex LH-20 column chromatography and recrystallization various separation techniques,19 compounds had been isolated from the ethyl acetate and n-butanol fraction of G.rigescens,and their structures were identified by using NMR and EI-MS spectroscopic methods.These compounds include: 4-(?-D-glucopyranosyloxy)benzaldehyde(1);3,4-dimethoxyphenyl-1-O-?-Dglucopyranoside(2);loganic acid(3);6'-O-?-D-glucopyranosyl loganic acid(4);gentiopicroside(5);luteolin-7-O-?-D-glucoside(6);swertioside(7);3,4-dihydroxyacetophenone(8);2,3-dihydroxybenzoic acid(9);catechol(10);ursolic acid(11);(E)-caffeic acid(12);?-sitosterol(13);gentiogenal(14);oleanolic acid(15);(E)-2,3,5,4'-tetrahydroxystilbene-2-O-?-D-glucoside(16);mangiferin(17);5-hydroxymethyl-furaldehyde(18);4-methyl umbelliferolactone(19);The fourth chapter summarizes and prospects the work done in this paper.