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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Chemical pattern recognition of the traditional Chinese medicinal herb, epimedium.

January 1998 (has links)
by Kwan Yee Ting, Chris. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 44-48). / Abstract also in Chinese. / Acknowledgements --- p.i / Abstract --- p.ii / Table of Contents --- p.v / List of Figures --- p.ix / List of Tables --- p.x / Chapter Part 1. --- Introduction --- p.1 / Chapter 1.1 --- Identification of TCM --- p.1 / Chapter 1.2 --- Chemical Pattern Recognition --- p.2 / Chapter 1.3 --- Discriminant Analysis --- p.3 / Chapter 1.4 --- Epimedium --- p.5 / Chapter 1.5 --- High Performance Liquid Chromatography --- p.6 / Chapter 1.6 --- Objectives of this work --- p.8 / Chapter Part 2. --- Chemical Analysis --- p.9 / Chapter 2.1 --- Sources of Epimedium samples --- p.9 / Chapter 2.2 --- Extraction --- p.9 / Chapter 2.2.1 --- Sample Pre-treatment --- p.9 / Chapter 2.2.2 --- Extraction Procedure --- p.9 / Chapter 2.2.3 --- Extraction Recovery --- p.11 / Chapter 2.3 --- Instrumental Analysis --- p.11 / Chapter 2.3.1 --- Chromatographic Operating Conditions --- p.12 / Chapter 2.3.2 --- Preparation of Calibration Graph --- p.12 / Chapter 2.3.3 --- Sample injection --- p.13 / Chapter 2.4 --- Results and Discussion --- p.13 / Chapter 2.4.1 --- Linearity of the Calibration Graph --- p.13 / Chapter 2.4.2 --- Development of Analysis Procedure --- p.15 / Chapter 2.4.2.1 --- Sample Pre-treatment --- p.15 / Chapter 2.4.2.2 --- Extractant --- p.15 / Chapter 2.4.2.3 --- Purification of Extract --- p.15 / Chapter 2.4.2.4 --- Extraction Time --- p.17 / Chapter 2.4.2.5 --- Solvent Gradient --- p.18 / Chapter 2.4.2.6 --- Detection --- p.19 / Chapter 2.4.3 --- Quantitative Analysis --- p.19 / Chapter 2.4.3.1 --- Extraction Recovery --- p.19 / Chapter 2.4.3.2 --- Icariin Content --- p.20 / Chapter 2.5 --- Conclusions --- p.22 / Chapter Part 3. --- Chemical Pattern Recognition --- p.24 / Chapter 3.1 --- Materials and Methods --- p.24 / Chapter 3.1.1 --- Chromatographic Results --- p.24 / Chapter 3.1.2 --- Patterns of Epimedium Samples --- p.24 / Chapter 3.1.3 --- Computer Program --- p.25 / Chapter 3.1.4 --- Variable Extraction --- p.25 / Chapter 3.1.4.1 --- Variable Extraction Parameters --- p.25 / Chapter 3.1.4.2 --- Variable Extraction Methods --- p.26 / Chapter 3.1.4.3 --- Transformation of Variables --- p.27 / Chapter 3.1.5 --- Variable Selection --- p.27 / Chapter 3.1.6 --- Predictive Power of the Recognition Model --- p.28 / Chapter 3.2 --- Results --- p.28 / Chapter 3.2.1 --- Accuracy of the Recognition Models --- p.28 / Chapter 3.2.2 --- Classification Functions --- p.29 / Chapter 3.2.3 --- Casewise Results of Recognition Model IV --- p.31 / Chapter 3.2.4 --- Plotting of the Best Two Canonical Discriminant Functions --- p.33 / Chapter 3.3 --- Discussion --- p.33 / Chapter 3.3.1 --- Meaning of Extracted Variables --- p.33 / Chapter 3.3.2 --- Limitations of Variable Extraction Methods --- p.34 / Chapter 3.3.3 --- Importance of the Variable Extraction Methods --- p.34 / Chapter 3.3.4 --- "Reasons for the Poor Performance in Recognition Models I, II and III" --- p.35 / Chapter 3.3.5 --- Selected Variables in Model IV --- p.35 / Chapter 3.3.6 --- Misclassified Samples --- p.36 / Chapter 3.3.7 --- Quality Assessment --- p.38 / Chapter 3.3.8 --- Comparison with Another Chemical Pattern Recognition Method for the Identification of Epimedium --- p.39 / Chapter 3.3.9 --- Potential Usage of the Pattern Recognition Method --- p.42 / Chapter 3.3.10 --- Advantage of the Pattern Recognition Method --- p.42 / Chapter 3.3.11 --- Disadvantage of Discriminant Analysis --- p.42 / Chapter 3.4 --- Conclusions --- p.43 / References --- p.44 / Appendix I Epimedium Species in China --- p.49 / Appendix II --- p.50 / Chapter II.1 --- Chromatograms of Samples of Epimedium sagittatum --- p.50 / Chapter II.2 --- Chromatograms of Samples of Epimedium pubescens --- p.57 / Chapter II.3 --- Chromatograms of Samples of Epimedium koreanum --- p.61 / Chapter II.4 --- Chromatograms of Samples of Epimedium leptorrhizum --- p.67 / Chapter II.5 --- Chromatograms of Samples of Epimedium wnshanese --- p.69 / Chapter II.6 --- Chromatograms of Samples of Epimedium brevicornum --- p.72 / Appendix III Log-transformed Values of Variables --- p.75
2

Recognition of Chinese medicinal herbs by gas chromatgraphy [sic]. / Recognition of Chinese medicinal herbs by gas chromatography

January 1998 (has links)
by Suk Che Ho. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 86-88). / Abstract also in Chinese. / Abstract --- p.i / Acknowledgments --- p.iii / Dedication --- p.iv / Abbreviations --- p.v / Table of Contents --- p.vi / Chapter Chapter 1: --- Introduction --- p.1 / Chapter 1.1 --- Overview of Chinese Medicinal Herbs containing essential oils --- p.1 / Chapter 1.1.1 --- Introduction of Chinese Medicinal Herbs --- p.1 / Chapter 1.1.2 --- Chinese Medicinal Herbs containing essential oils --- p.2 / Chapter 1.2 --- Recognition of Chinese Medicinal Herbs --- p.2 / Chapter 1.2.1 --- Traditional method in recognition of Chinese Medicinal Herbs (CMH) --- p.2 / Chapter 1.2.2 --- Instrumental Methods for the recognition of CMH --- p.4 / Chapter 1.2.3 --- The use of GC and GC/MS on CMH --- p.4 / Chapter 1.3 --- Motivation and objective of this research --- p.5 / Chapter 1.3.1 --- Motivation --- p.6 / Chapter 1.3.2 --- Objective of this research --- p.7 / Chapter 1.4 --- Outline of the methodology and arrangement of the thesis --- p.8 / Chapter Chapter 2: --- Experimental Setup --- p.11 / Chapter 2.1 --- Reagents and materials --- p.11 / Chapter 2.1.1 --- Reagents and glassware --- p.11 / Chapter 2.1.2 --- Materials --- p.11 / Chapter 2.2 --- Sample pretreatment --- p.14 / Chapter 2.3 --- Extraction of essential oils from the herbal samples --- p.14 / Chapter 2.3.1 --- Traditional extraction methods for essential oils --- p.14 / Chapter 2.3.2 --- Extraction by hydrodistillation using Dean and Stark-type trap --- p.15 / Chapter 2.4 --- Results --- p.17 / Chapter 2.4.1 --- Comparison with literature data --- p.17 / Chapter 2.4.2 --- Reproducibility of the extraction --- p.17 / Chapter 2.4.3 --- Recovery test --- p.26 / Chapter 2.5 --- Discussion --- p.27 / Chapter Chapter3: --- Instrumental Analysis of the Essential Oils --- p.29 / Chapter 3.1 --- GC analysis --- p.29 / Chapter 3.1.1 --- Instrumentation --- p.29 / Chapter 3.1.2 --- Instrumental settings --- p.31 / Chapter 3.1.3 --- The use of GC in the analysis of essential oils --- p.31 / Chapter 3.1.3.1 --- Qualitative data --- p.31 / Chapter 3.1.3.2 --- Quantitative data --- p.33 / Chapter 3.1.3.3 --- Dilution strategy --- p.33 / Chapter 3.1.4 --- Results --- p.36 / Chapter 3.1.4.1 --- Precision test --- p.36 / Chapter 3.1.4.2 --- Linearity --- p.39 / Chapter 3.2 --- GC/MS analysis --- p.41 / Chapter 3.2.1 --- Instrumentation --- p.41 / Chapter 3.2.2 --- Instrumental settings --- p.42 / Chapter 3.2.3 --- The use of GC/MS in the analysis of essential oils --- p.43 / Chapter 3.2.3.1 --- Identification by GC/MS --- p.43 / Chapter 3.2.3.2 --- Abundance information --- p.43 / Chapter 3.2.4 --- Results --- p.44 / Chapter 3.2.4.1 --- Precision test --- p.44 / Chapter 3.2.4.2 --- Linearity --- p.46 / Chapter 3.2.4.3 --- Detection limit --- p.48 / Chapter 3.2.4.4 --- Chromatographic patterns of herbal samples obtained by GC/MS --- p.49 / Chapter 3.3 --- Discussion --- p.49 / Chapter Chapter 4: --- Development of a system for recognition --- p.52 / Chapter 4.1 --- Introduction --- p.52 / Chapter 4.2 --- Analysis of chromatographic patterns --- p.53 / Chapter 4.2.1 --- Extraction of “effective´ح peaks --- p.54 / Chapter 4.2.2 --- Extraction of “characteristic´ح peaks --- p.56 / Chapter 4.3 --- Library section --- p.60 / Chapter 4.3.1 --- Calculation of relative retention indices --- p.60 / Chapter 4.3.2 --- Normalization factors --- p.61 / Chapter 4.4 --- Matching section --- p.62 / Chapter 4.4.1 --- Overview of the matching method --- p.62 / Chapter 4.4.2 --- Input --- p.63 / Chapter 4.4.3 --- Matching strategy --- p.64 / Chapter 4.4.4 --- Matching algorithms --- p.64 / Chapter 4.4.4.1 --- "Matching with “characteristic"" peaks" --- p.64 / Chapter 4.4.4.2 --- Matching with “effective´ح peaks --- p.65 / Chapter 4.4.5 --- Calculation of similarity scores --- p.66 / Chapter 4.4.6 --- Output --- p.69 / Chapter Chapter 5: --- Performance of the proposed recognition system --- p.70 / Chapter 5.1 --- Recognition performance of the database --- p.70 / Chapter 5.1.1 --- Definition of similarity --- p.70 / Chapter 5.1.2 --- Performance test of the recognition method --- p.70 / Chapter 5.1.2.1 --- Candidates in the library file --- p.70 / Chapter 5.1.2.2 --- Unknown not found in the library file --- p.75 / Chapter 5.1.3 --- Information drawn from the scores --- p.77 / Chapter 5.1.3.1 --- Recognition of the unknown sample in terms of similarity --- p.77 / Chapter 5.1.3.2 --- Relationship between the herbal drugs --- p.79 / Chapter 5.2 --- Applicability of the proposed methodology --- p.80 / Chapter 5.3 --- Limitation of the proposed methodology --- p.81 / Chapter 5.4 --- Future prospect --- p.81 / Chapter Chapter 6: --- Conclusion --- p.83 / References --- p.86 / Appendices / Chapter A. --- Linearity of calibration graphs using GC --- p.A1 / Chapter B. --- Linearity of calibration graphs using GC/MS --- p.A3 / Chapter C. --- GC/MS chromatograms of the herbal samples --- p.A5 / Chapter D. --- "Relative retention times of “effective"" and ""characteristic"" peaks" --- p.A28
3

Characterization of selected Chinese medicinal plants using conventional and novel molecular methods. / CUHK electronic theses & dissertations collection

January 2001 (has links)
Mak Chun-yin. / "February 2001." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (p. 156-169). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
4

Chemical constituents and analysis of rhizoma chuanxiong using capillary electrophoresis.

January 2002 (has links)
Ip Yee-man. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (leaves 85-89). / Abstracts in English and Chinese. / Acknowledgement --- p.i / Abstract --- p.iii / Table of Contents --- p.vi / Abbreviations --- p.xi / List of Figures --- p.xiii / List of Tables --- p.xvii / Chapter / Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Background --- p.1 / Chapter 1.2 --- Quality control of Chinese herbal medicine --- p.2 / Chapter 1.3 --- Rhizoma Chuanxiong --- p.4 / Chapter 1.3.1. --- General description --- p.4 / Chapter 1.3.2. --- Chemical constituents --- p.4 / Chapter 1.3.3. --- Pharmacology --- p.7 / Chapter 1.3.4 --- Instrumental analysis --- p.9 / Chapter 1.3.4.1 --- Thin Layer Chromatography (TLC) --- p.9 / Chapter 1.3.4.2 --- Gas Chromatography (GC) --- p.10 / Chapter 1.3.4.3 --- High Performance Liquid Chromatography (HPLC) --- p.10 / Chapter 1.3.4.4 --- Capillary Electrophoresis (CE) --- p.10 / Chapter 1.4 --- Objectives of the study --- p.11 / Chapter 2. --- "Isolation, Characterization and Identification of Reference Compounds" --- p.13 / Chapter 2.1 --- General experiment procedures --- p.13 / Chapter 2.1.1. --- Solvents for chromatographic separation --- p.13 / Chapter 2.1.2 --- Chromatographic methods --- p.13 / Chapter 2.1.2.1 --- Adsorption column chromatography --- p.13 / Chapter 2.1.2.2 --- Thin layer chromatography --- p.13 / Chapter 2.1.2.3 --- Preparative layer chromatography --- p.14 / Chapter 2.1.3 --- Determination of physical data --- p.14 / Chapter 2.1.3.1 --- Infrared (IR) absorption spectra --- p.14 / Chapter 2.1.3.2 --- Nuclear Magnetic Resonance (NMR) spectra --- p.14 / Chapter 2.1.3.3 --- Mass spectra (MS) --- p.15 / Chapter 2.1.3.4 --- X-ray crystallography --- p.15 / Chapter 2.1.4 --- Authentic reference compounds --- p.15 / Chapter 2.2 --- "Procurement, extraction and initial fractionation of Rhizoma Chuanxiong" --- p.15 / Chapter 2.3 --- Chromatographic separation of the chloroform extract --- p.16 / Chapter 2.3.1 --- Chromatographic separation of fraction F1002 --- p.16 / Chapter 2.3.1.1 --- Spectral data for the characterization of compound 1 [5-(hydroxymethyl)- 2- furancarboxaldehyde] --- p.17 / Chapter 2.3.2 --- Column chromatographic separation of fraction F1003A --- p.17 / Chapter 2.3.2.1 --- Spectral data for the characterization of compound 2 (oleic acid) --- p.18 / Chapter 2.3.2.2 --- Physical data for the characterization of compound 3 (ferulic acid) --- p.18 / Chapter 2.3.3 --- Preparative layer chromatographic separation of Fraction F1010 --- p.19 / Chapter 2.3.3.1 --- Spectral data for the characterization of compound 4 (daucosterol) --- p.19 / Chapter 2.4 --- Column chromatographic separation of the hexane extract --- p.19 / Chapter 2.4.1 --- Removal of fatty acids in fraction F2005 and F2006 by partition --- p.20 / Chapter 2.4.2 --- Column chromatographic separation of fraction F2005M --- p.20 / Chapter 2.4.2.1 --- Spectral data for the characterization of compound 5 (butylidenephthalide) --- p.20 / Chapter 2.4.2.2 --- Spectral data for the characterization of compound 6 (butylphthalide) --- p.21 / Chapter 2.4.3 --- Column chromatographic separation of fraction F2006M --- p.21 / Chapter 2.4.3.1 --- "Spectral data for the characterization of compound 7 (Z, Z'-6.6', 7.3'a- diligustilide)" --- p.21 / Chapter 2.4.4 --- Colum chromatographic separation of fraction --- p.22 / Chapter 2.4.4.1 --- Spectral data for the characterization of compound 8 (pregnenolone) --- p.22 / Chapter 2.4.4.2 --- "Spectral data for the characterization of compound 9 [5,5- oxydimethylenebis(2-furaldehyde)]" --- p.23 / Chapter 2.5 --- Results and Discussion --- p.24 / Chapter 2.5.1 --- Identification of compound 1 [5-(hydroxymethyl)-2- furancarboxaldehyde] --- p.24 / Chapter 2.5.2 --- Identification of compound 2 (oleic acid) --- p.25 / Chapter 2.5.3 --- Identification of compound 3 (ferulic acid) --- p.26 / Chapter 2.5.4 --- Identification of compound 4 (daucosterol) --- p.26 / Chapter 2.5.5 --- Identification of compound 5 (butylidenephthalide) --- p.27 / Chapter 2.5.6 --- Identification of compound 6 (butylphthalide) --- p.28 / Chapter 2.5.7 --- "Identification of compound 7 (Z, Z'-6.6', 7.3'a-diligustilide)" --- p.30 / Chapter 2.5.8 --- Identification of compound 8 (pregnenolone) --- p.31 / Chapter 2.5.9 --- "Identification of compound 9 [5,5'-oxydimethylenebis(2-furaldehyde)]" --- p.32 / Chapter 2.6 --- Conclusions --- p.34 / Chapter 3. --- Analysis of Rhizoma Chuanxiong by Capillary Electrophoresis --- p.35 / Chapter 3.1 --- Introduction --- p.35 / Chapter 3.1.1 --- Capillary electrophoreis system --- p.35 / Chapter 3.1.2 --- Principles of separation --- p.36 / Chapter 3.1.3 --- Considerations on development of analysis method --- p.41 / Chapter 3.2 --- Experimental --- p.43 / Chapter 3.2.1 --- Reagents and materials --- p.43 / Chapter 3.2.2 --- Reference compounds --- p.43 / Chapter 3.2.3 --- Instrumentation and apparatus --- p.44 / Chapter 3.2.4 --- Experimental procedures --- p.45 / Chapter 3.2.4.1 --- Preparation of running buffer solution --- p.45 / Chapter 3.2.4.2 --- Preparation of standard solutions --- p.46 / Chapter 3.2.4.3 --- Preparation of Rhizoma Chuanxiong extracts --- p.47 / Chapter 3.2.4.4 --- Flushing of capillaries --- p.47 / Chapter 3.2.4.5 --- Conditions of separation --- p.48 / Chapter 3.3 --- Results and Discussion --- p.48 / Chapter 3.3.1 --- Preliminary experiments --- p.48 / Chapter 3.3.1.1 --- Addition of surfactants --- p.51 / Chapter 3.3.2 --- Effect of buffer concentration --- p.54 / Chapter 3.3.3 --- Effect of SDS concentration --- p.59 / Chapter 3.3.4 --- Addition of organic modifier --- p.63 / Chapter 3.3.5 --- Reproducibility of the proposed method --- p.68 / Chapter 3.3.6 --- Quantitative analysis of seven standard compounds --- p.70 / Chapter 3.3.7 --- Application of the developed methodology --- p.74 / Chapter 3.3.8 --- Conclusions --- p.83 / References --- p.85 / Appendices / Appendix 1.1.1 1H-NMR spectrum of 5-(hydroxymethyl)-2-furancarboxaldehyde --- p.90 / Appendix 1.1.2 13C-NMR spectrum of 5-(hydroxyinethyl)-2-furancarboxaldehyde --- p.90 / Appendix 1.2 X-ray crystallographic data of ferulic acid --- p.91 / Appendix 1.3 13C-NMR spectrum of butylidenephthalide --- p.96 / Appendix 1.4.1 1 H-NMR spectrum of butylphthalide --- p.97 / Appendix 1.4.2 13C-NMR spectrum of butylphthalide --- p.97 / "Appendix 1.5 X-ray crystallographic data of z, z', 6.6', 7.3'a-diligustilide" --- p.98 / "Appendix 1.6 X-ray crystallographic data of 5,5'-oxydimethylenebis(2-furaldehyde)" --- p.105 / Appendix 2.1 Details of quantitative analysis of 5-(hydroxymethyl)-2-furancarboxaldehyde --- p.112 / Appendix 2.2 Details of quantitative analysis of ligustrazin hydrochloride --- p.112 / "Appendix 2.3 Details of quantitative analysis of 5,5'-oxydimethylenebis(2-furaldehyde)" --- p.113 / Appendix 2.4 Details of quantitative anlaysis of ferulic acid --- p.113 / Appendix 2.5 Details of quantitative analysis of butylphthalide --- p.114 / Appendix 2.6 Details of quantitative analysis of butylidenephthalide --- p.114 / "Appendix 2.7 Details of quantitative anlaysis of z,z', 6.6', 7.3'a-diligustilide" --- p.115 / Appendix 3.1 Quantitative analysis of Chuanxiong sample from Hong Kong (HK1) --- p.115 / Appendix 3.2 Quantitaive analysis of Chuanxiong sample from Hong Kong (HK2) --- p.116 / Appendix 3.3 Quantitative analysis of Chuanxiong sample from Sichuan (SC1) --- p.116 / Appendix 3.4 Quantitative analysis of Chuanxiong sample from Sichuan (SC2) --- p.117 / Appendix 3.5 Quantitative anlaysis of Chuanxiong samplefrom Fujian (FJ) --- p.117
5

Analytical and pharmacokinetic studies of the main chemical ingredients of rhizoma chuanxiong. / CUHK electronic theses & dissertations collection

January 2005 (has links)
and senkyunolide A were found as the three major compounds in all herbal samples investigated. In addition, great variations in both total and individual content of each of the ten main components investigated were observed in samples of different origins and those collected from a GAP developing base in the same or different years, suggesting the necessity of a thorough quality control for Rhizoma Chuanxiong. / Extraction of the main ingredients from Rhizoma Chuanxiong by supercritical fluid extraction using CO2 was investigated. An appropriate SCFE method for Chuanxiong was developed with the mild conditions for the extraction of the unstable components. The method provided a high recovery and adequate reproducibility, and may be suitable for large-scale industry extraction of Chuanxiong. / Firstly, a total of sixteen ingredients were identified from Chuanxiong by HPLC-UV-MS and HPLC-UV analyses. Among them, ten ingredients were determined to be the main components in Chuanxiong. A simple, sensitive and specific HPLC-UV method was developed, for the first time, to simultaneously qualitatively and quantitatively determine twelve ingredients, including the identified ten main ingredients, plus vanillin and tetramethylpyrazine (TMP), which although were not found in the present study, had also been reported to be present in Rhizoma Chuanxiong. The developed assay was fully validated and provided adequate accuracy and reproducibility for all compounds analyzed. It was applied successfully to simultaneously quantify all main constituents in different Chuanxiong samples. TMP and vanillin were not detected, while Z-ligustilide, coniferylferulate. / Furthermore, a comprehensive stability study was carried out for the first time with the three major components senkyunolide A, coniferylferulate, Z-ligustilide and the main ingredient 3-butylidenephthalide, in pure form or Chuanxiong extract obtained from supercritical fluid extraction using CO 2 (SCFE) under different conditions. Results showed that both sun light and elevated temperature led to degradations of these components to different extents. Owing to such thermal and light instability, post-harvest drying and processing procedures could significantly alter the chemical profile of Chuanxiong herb, and thus also need to be well controlled. / In conclusion, analytical and pharmacokinetic studies of the main chemical ingredients in Rhizoma Chuanxiong were systematically conducted. The results revealed, for the first time, that senkyunolide A, Z-ligustilide and 3-butylidenephthalide might be the primary chemical ingredients contributing to the beneficial effects of Chuanxiong. / Oral bioavailability was about 8%, 3% and 20% for senkyunolide A, Z-ligustilide and 3-butylidenephthalide, respectively. Instability in the gut mainly contributed to a low oral bioavailability of senkyunolide A. First-pass metabolism in the liver also contributed to the low oral bioavailability but to a much lower extent. For Z-ligustilide, extensive first-pass metabolism in the liver and degradation in the stomach only partly accounted for its poor oral bioavailability, while other gut factors involved are still unknown. In the case of 3-butylidenephthalide, its low oral bioavailability was attributed to extensive first-pass metabolism in both the gut and the liver. / Pharmacokinetic fates of the main ingredients in Chuanxiong SCFE extract were firstly evaluated in rats. After a single intravenous and oral administration, only senkyunolide A, Z-ligustilide and 3-butylidenephthalide were determined as the main herb related components in plasma. Coniferylferulate, although it is one of the abundant principles in the herb, was not detected in the plasma even immediately after dosing. / Pharmacokinetic profiles of senkyunolide A, Z-ligustilide and 3-butylidenephthalide were further elucidated individually in rats. All three compounds exhibited rapid absorption, extensive distribution, and rapid elimination. The pharmacokinetic profile of senkyunolide A followed a dose-independent pattern, whereas Z-ligustilide exhibited dose-dependent kinetics. 3-Butylidenephthalide underwent enterohepatic re-circulation. / Rhizoma Chuanxiong is derived from the dried rhizome of Ligusticum chuanxiong Hort. (Umbelliferae). In China, it has been widely prescribed for the treatment of cerebro- and cardio-vascular diseases for thousands of years. However, its chemical and pharmacological basis is poorly understood. In the present study, analytical methods for qualitative and quantitative determination of the main chemical components in Chuanxiong herb were developed. Furthermore, pharmacokinetic profiles of the main chemical ingredients in Chuanxiong were systematically investigated in rats for the first time. / The metabolic profiles of senkyunolide A, Z-ligustilide and 3-butylidenephthalide were investigated both in vivo and in vitro. Oxidation and hydration were found to be the main metabolic pathways for all three compounds. In addition, glutathione conjugation of senkyunolide A and Z-ligustilide also occurred in the rat. A novel metabolite 3-hydroxy-3-butylphthalide was identified as the major metabolite of 3-butylidenephthalide generated by a direct hydration, and was shown to have significantly higher plasma levels than those of the parent compound. Furthermore, the main metabolites detected in the plasma of rats administered with Chuanxiong extract were generated from senkyunolide A, Z-ligustilide and 3-butylidenephthalide. / Yan Ru. / "May 2005." / Adviser: Ge Lin. / Source: Dissertation Abstracts International, Volume: 68-03, Section: B, page: 1583. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (p. 244-255). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.

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