Study On The Chemical Constituents And Quality Evaluation Method For Pterocephalus Hookeri

Yishoucao (in Chinese), which has been frequently used in Tibet for a long time, isthe dry root or total herb of Pterocephalus hookeri (C.B.Clarke) H eck. and P.bretschneideri (Batal.) Pritz. It has several pharmacological activities such as clearanceand resolving of exterior heat, removing dampness and relieving pain, etc. And it hasbeen mainly used for the treatment of influenza, dysentery, febrile diseases andrheμmatism etc.In order to identify the characteristics active compounds in Yishoucao and developanalytical methods by using those compounds as chemical markers. In the present study,the systematic chemical separation and identification, preliminary in vitropharmacological tests and quality evaluation method for Yishoucao were studied. Andfinally to provide scientific basis for improving the quality evaluation of Yishoucao.The first part of the thesis is the literature review, which is focused on the recentdevelopment about the chemical compositions, pharmacological activities and qualityevaluation methods of Yishoucao.The second part of the thesis is about the chemical isolation and structureidentification. Seventeen pure compounds were separated from Yishoucao by usingsilica-gel chromatography and preparative thin layer chromatography. The structures forten of the seventeen compounds were identified by their MS and NMR spectra. Theyare twenty alkyl ether, hexadecanoic acid, pentatriacontane, β-sitosterol, ursolic acid,oleanolic acid, oleanonic acid, p-hydroxy benzaldehyde,5,7,3’,4’,6’-pentahydroxyflavanone and methionine, respectively. Furthermore, twenty alkyl ether,pentatriacontane, p-hydroxy benzaldehyde,5,7,3’,4’,6’-pentahydroxy flavanone andmethionine were separated from Yishoucao for the first time.The third part of the thesis is in vitro antimicrobial test of Yishoucao. Theantibacterial properties of all the extracts from Yishoucao were tested against threebacterial strains; the values of the minimum inhibitory concentration and minimumbactericidal concentration were determined. The results indicated that different extracts,especially the water, n-butanol and ethyl acetate extracts, of Yishoucao show inhibitoryeffect on the investigated bacterial strains. At the same time, we investigated theantibacterial properties of pure compounds which separated from Yishoucao. Simultaneous determination of three main active components includes oleanolicacid, ursolic acid and oleanonic acid in Yishoucao by HPLC-DAD-ELSD was describedin the forth part of the thesis. The contents of those three compounds in14baths ofYishoucao both before and after acid hydrolysis. Furthermore, the fatty acids inYishoucao were also analyzed by GC-MS.