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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.
21

ANTHOCYANIN COLOR ENHANCEMENT BY USING CATECHIN AS COPIGMENTS AND STABILITY DURING STORAGE

Hsiao, Hui-Chun 18 August 2014 (has links)
No description available.
22

Studies on the mechanisms and anti-tumor activities of green tea epicatechin isomers.

January 2000 (has links)
by Ip Wai-Ki. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 213-233). / Abstracts in English and Chinese. / ACKNOWLEDGEMENTS --- p.i / ABBREVIATIONS --- p.ii / ABSTRACT --- p.vi / 撮要 --- p.x / TABLE OF CONTENTS --- p.xiv / Chapter CHAPTER 1: --- GENERAL INTRODUCTION / Chapter 1.1 --- Hematopoiesis --- p.1 / Chapter 1.1.1 --- Introduction to Hematopoiesis --- p.1 / Chapter 1.1.2 --- Cytokines in Hematopoiesis --- p.4 / Chapter 1.2 --- Leukemia --- p.6 / Chapter 1.2.1 --- Leukemia: Abnormalities in Blood Cell Formation --- p.6 / Chapter 1.2.2 --- Classification of Leukemia --- p.8 / Chapter 1.2.3 --- The Causes and Molecular Basis of Leukemia --- p.8 / Chapter 1.2.4 --- Therapy of Leukemia --- p.11 / Chapter 1.2.5 --- Control of Leukemia by Hematopoietic Growth Factors and Other Compounds --- p.12 / Chapter 1.2.6 --- Molecular Control of Apoptosis and Cell Cycle in Leukemia --- p.13 / Chapter 1.2.6.1 --- Regulation of Cell Cycle and Apoptosis by Genes and Regulatory Proteins --- p.14 / Chapter 1.2.6.1.1 --- Cell Cycle --- p.14 / Chapter 1.2.6.1.2 --- Apoptosis --- p.15 / Chapter 1.2.6.2 --- Role of Apoptosis and Cell Cycle in the Development of Leukemia --- p.17 / Chapter 1.3 --- Green Tea --- p.19 / Chapter 1.3.1 --- Origin and Cultivation of Tea Plants --- p.19 / Chapter 1.3.2 --- Classification and Manufacturing of Tea --- p.21 / Chapter 1.3.3 --- The Chemistry of Tea --- p.22 / Chapter 1.3.3.1 --- Chemical Composition of Tea --- p.22 / Chapter 1.3.3.2 --- Separation and Purification of Green Tea Polyphenols --- p.27 / Chapter 1.3.3.3 --- The Chemical Properties of Green Tea Polyphenols --- p.28 / Chapter 1.3.4 --- Bioavailability and Pharmacokinetic of Green Tea Epicatechins --- p.28 / Chapter 1.3.4.1 --- Human Studies --- p.29 / Chapter 1.3.4.2 --- Animal Studies --- p.30 / Chapter 1.3.5 --- Physiological and Pharmacological Activities of Green Tea Catechins --- p.31 / Chapter 1.3.5.1 --- Anti-oxidative Activity --- p.32 / Chapter 1.3.5.2 --- Hypocholesterolemic and Hypolipidemic Activity --- p.33 / Chapter 1.3.5.3 --- Anti-inflammatory Activity --- p.34 / Chapter 1.3.5.4 --- Anti-microbial Activity --- p.35 / Chapter 1.3.5.5 --- Anti-mutagenic Activity --- p.36 / Chapter 1.3.5.6 --- Anti-carcinogenesis --- p.37 / Chapter 1.3.5.7 --- Direct Anti-tumor Activity --- p.41 / Chapter 1.3.5.8 --- Modulating Activity in Endocrine System --- p.43 / Chapter 1.3.5.9 --- Other Biological Activities --- p.43 / Chapter 1.3.6 --- Possible Anti-cancer Mechanisms of Green Tea Epicatechins --- p.44 / Chapter 1.3.6.1 --- Modulation of Anti-tumor Immunity --- p.44 / Chapter 1.3.6.2 --- Direct Growth Inhibition by Controlling the Signal Transduction Pathways --- p.45 / Chapter 1.3.6.3 --- Induction of Apoptosis and Cell Cycle Arrest --- p.46 / Chapter 1.3.6.4 --- Inhibition of Tumor Metastasis --- p.47 / Chapter 1.4 --- Aims and Scopes of This Investigation --- p.48 / Chapter CHAPTER 2: --- MATERIALS AND METHODS / Chapter 2.1 --- Materials --- p.50 / Chapter 2.1.1 --- Animals --- p.50 / Chapter 2.1.2 --- Cell Lines --- p.50 / Chapter 2.1.3 --- Sheep Red Blood Cells (SRBC) --- p.52 / Chapter 2.1.4 --- "Cell Culture Medium, Buffers and Reagents" --- p.52 / Chapter 2.1.5 --- Tea Extracts and Green Tea Epicatechins --- p.56 / Chapter 2.1.6 --- Recombinant Cytokines --- p.57 / Chapter 2.1.7 --- Vitamin Analogs --- p.59 / Chapter 2.1.8 --- Taxol (Baccatin III N-benzoyl-β-phenyllisoserine ester) --- p.59 / Chapter 2.1.9 --- 18β-Glycyrrhetinic Acid (18β-GA) --- p.60 / Chapter 2.1.10 --- [methyl-3H] Thymidine (3H-TdR) --- p.60 / Chapter 2.1.11 --- Liquid Scintillation Cocktail --- p.60 / Chapter 2.1.12 --- Reagents and Buffers for Flow Cytometery --- p.61 / Chapter 2.1.13 --- Reagents for DNA Extraction --- p.62 / Chapter 2.1.14 --- Reagents for Total RNA Isolation --- p.63 / Chapter 2.1.15 --- Reagents and Buffers for RT-PCR Study --- p.64 / Chapter 2.1.16 --- Reagents and Buffers for Gel Electrophoresis --- p.67 / Chapter 2.1.17 --- Reagents and Buffers for Western Blot Analysis --- p.68 / Chapter 2.2 --- Methods --- p.77 / Chapter 2.2.1 --- Culture of the Leukemic Cell Lines --- p.77 / Chapter 2.2.2 --- "Isolation, Preparation and Culture of Primary Mouse Cells" --- p.77 / Chapter 2.2.3 --- Determination of Cell Viability --- p.78 / Chapter 2.2.4 --- [3H]-TdR Incorporation Assay --- p.79 / Chapter 2.2.5 --- Cell Morphology Study --- p.79 / Chapter 2.2.6 --- Apoptosis Study --- p.80 / Chapter 2.2.7 --- Animal Studies --- p.81 / Chapter 2.2.8 --- Gene Expression Study --- p.82 / Chapter 2.2.9 --- Protein Expression Study --- p.85 / Chapter 2.2.10 --- Statistical Analysis --- p.88 / Chapter CHAPTER 3: --- THE ANTI-TUMOR ACTIVITIES OF TEA EXTRACTS AND PURIFIED GREEN TEA EPICATECHIN ISOMERS ON VARIOUS LEUKEMIC CELL LINES / Chapter 3.1 --- Introduction --- p.89 / Chapter 3.2 --- Results --- p.91 / Chapter 3.2.1 --- The Effects of Tea Extracts on Various Leukemia Cells --- p.91 / Chapter 3.2.1.1 --- Differential Anti-proliferative Effect of Different Tea Extracts on Various Leukemic Cell Lines In Vitro --- p.91 / Chapter 3.2.1.2 --- Differential Cytotoxic Effect of Different Tea Extracts on the Murine Lymphocytic Leukemia L1210 Cells In Vitro --- p.92 / Chapter 3.2.1.3 --- Induction of Apoptosis in HL-60 Cells by Different Tea Extracts In Vitro --- p.92 / Chapter 3.2.2 --- The Effects of Purified Green Tea Epicatechin Isomers on Various Leukemic Cell Lines --- p.101 / Chapter 3.2.2.1 --- In Vitro Anti-proliferative Effect of Green Tea Epicatechin Isomers on Various Human and Murine Leukemic Cell Lines --- p.101 / Chapter 3.2.2.2 --- In Vitro Cytotoxic Effect of Green Tea Epicatechin Isomers on Various Human and Murine Leukemic Cell Lines --- p.117 / Chapter 3.2.2.3 --- Effects of Green Tea Epicatechin Isomers on the Differentiation of Myeloid Leukemia Cells --- p.131 / Chapter 3.2.2.4 --- Apoptosis-Inducing Effect of Different Green Tea Epicatechin Isomers on HL-60 and JCS Cells --- p.134 / Chapter 3.2.2.5 --- Effect of EGCG on the In Vivo Tumorigenicity of Leukemia JCS and L1210 Cells --- p.142 / Chapter 3.3 --- Discussion --- p.144 / Chapter CHAPTER 4: --- MECHANISTIC STUDIES ON THE ANTI PROLIFERATIVE AND APOPTOSIS-INDUCING ACTIVITIES OF GREEN TEA EPICATECHIN ISOMERS ON LEUKEMIA CELLS / Chapter 4.1 --- Introduction --- p.149 / Chapter 4.2 --- Results --- p.152 / Chapter 4.2.1 --- Combining Effect of EGCG and Physiological Differentiation Inducers on the Proliferation of HL-60 and JCS Cells --- p.152 / Chapter 4.2.2 --- Combining Effect of EGCG and Cytokines on the Proliferation of JCS Cells --- p.155 / Chapter 4.2.3 --- Combining Effect ofEGCG and Other Phytochemicals on the Proliferation of HL-60 and JCS Cells --- p.161 / Chapter 4.2.4 --- Modulatory Effect of EGCG on the Expression of Apoptosis-regulatory Genes in HL-60 Cells --- p.168 / Chapter 4.2.5 --- Modulatory Effect of EGCG on the Expression of Growth-related and Apoptosis-regulatory Proteins in HL-60 Cells --- p.170 / Chapter 4.3 --- Discussion --- p.177 / Chapter CHAPTER 5: --- EFFECTS OF GREEN TEA EPICATECHIN ISOMERS ON THE GROWTH AND DIFFERENTIATION OF MURINE HEMATOPOIETIC CELLS / Chapter 5.1 --- Introduction --- p.184 / Chapter 5.2 --- Results --- p.186 / Chapter 5.2.1 --- In Vitro Effects of EGCG on Murine Lymphocytes --- p.186 / Chapter 5.2.1.1 --- In Vitro Effect of EGCG on the Proliferation of Murine Splenocytes --- p.186 / Chapter 5.2.1.2 --- In Vitro Effect of EGCG on the Mitogen-induced Proliferation of Murine Splenocytes --- p.186 / Chapter 5.2.1.3 --- Cytotoxic Effect of EGCG on Murine Lymphocytes --- p.189 / Chapter 5.2.2 --- Primary Humoral Immune Response to SRBCin EGCG-treated Mice --- p.191 / Chapter 5.2.3 --- In Vitro Studies of the Effects of EGCG on Murine Bone Marrow Cells --- p.192 / Chapter 5.2.3.1 --- Effects of EGCG on the In Vitro Proliferation of Murine Bone Marrow Cells --- p.192 / Chapter 5.2.3.2 --- The Combining Effect of EGCG and Growth Factors on the In Vitro Proliferation of Murine Bone Marrow Cells --- p.192 / Chapter 5.2.3.3 --- In Vitro Cytotoxic Effect of EGCG on Murine Bone Marrow Cells --- p.196 / Chapter 5.2.4 --- Effect of EGCG on the Differentiation of Murine Bone Marrow Cells --- p.199 / Chapter 5.2.5 --- Combining Effects of EGCG and Growth Factors on the Morphology of Murine Bone Marrow Cells --- p.199 / Chapter 5.3 --- Discussion --- p.204 / Chapter CHAPTER 6: --- CONCLUSIONS AND FUTURE PERSPECTIVES --- p.207 / REFERENCES --- p.213
23

Tea catechins: epimerization, antioxidant activity and effect on body fatness in rats. / CUHK electronic theses & dissertations collection / Digital dissertation consortium

January 2004 (has links)
Xu Jinze. / "August 2004." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (p. 165-182). / 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 Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
24

The antioxidative and hypolipidemic activities of tea catechins.

January 1997 (has links)
by Chan Ping Tim Timothy. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references (leaves 129-141). / ACKNOWLEDGMENTS --- p.I / ABSTRACT --- p.II / LIST OF ABBREVIATIONS --- p.IV / TABLE OF CONTENTS --- p.VI / Chapter CHAPTER 1 --- GENERAL INTRODUCTION --- p.1 / Chapter 1.1 --- History of tea --- p.1 / Chapter 1.2 --- Botany and agriculture of tea --- p.1 / Chapter 1.3 --- Classification of tea --- p.2 / Chapter 1.4 --- Composition of tea --- p.4 / Chapter 1.5 --- Tea processing --- p.8 / Chapter 1.5.1 --- Manufacture of green tea --- p.8 / Chapter 1.5.2 --- Manufacture of black tea --- p.8 / Chapter 1.5.3 --- Manufacture of oolong tea --- p.10 / Chapter 1.6 --- Pharmacological effects of tea catechins --- p.13 / Chapter 1.6.1 --- Antioxidative activity --- p.13 / Chapter 1.6.2 --- Hypolipidemic activity --- p.14 / Chapter 1.6.3 --- Antimutagenic activity --- p.15 / Chapter 1.6.4 --- Anticarcinogenic activity --- p.15 / Chapter 1.6.5 --- Antibacterial activity --- p.16 / Chapter CHAPTER 2 --- ANTIOXIDATIVE ACTIVITIES OF TEA ETHANOL EXTRACTS AND GTC ON OXIDATION OF CANOLA OIL --- p.18 / Chapter 2.1 --- Introduction --- p.18 / Chapter 2.1.1 --- Lipid oxidation in food --- p.18 / Chapter 2.1.2 --- Phenolic antioxidants --- p.19 / Chapter 2.1.2.1 --- Major phenolic antioxidants used in food --- p.19 / Chapter 2.1.2.2 --- Mechanism of action of phenolic antioxidants --- p.20 / Chapter 2.1.2.3 --- BHA and its safety --- p.22 / Chapter 2.1.2.4 --- BHT and its safety --- p.24 / Chapter 2.1.3 --- Natural antioxidants --- p.24 / Chapter 2.2 --- Objectives --- p.26 / Chapter 2.3 --- Materials --- p.28 / Chapter 2.4 --- Methods --- p.28 / Chapter 2.4.1 --- GTC extraction --- p.28 / Chapter 2.4.2 --- "HPLC analysis of GTC," --- p.29 / Chapter 2.4.3 --- Isolation and purification of individual epicatechin isomers --- p.30 / Chapter 2.4.4 --- Ethanol extraction of tea --- p.30 / Chapter 2.4.5 --- Effect of tea ethanol extracts on oxygen consumption of canola --- p.31 / Chapter 2.4.6 --- Effect of GTC on oxygen consumption of canola oil --- p.32 / Chapter 2.4.7 --- Fatty acid analysis --- p.32 / Chapter 2.4.8 --- Thermal loss of BHT --- p.33 / Chapter 2.4.9 --- Thermal loss of GTC --- p.33 / Chapter 2.4.10 --- Statistics --- p.35 / Chapter 2.5 --- Results --- p.37 / Chapter 2.5.1 --- Antioxidative activities of tea ethanol extracts --- p.37 / Chapter 2.5.2 --- The yield and composition of GTC from jasmine tea --- p.51 / Chapter 2.5.3 --- Antioxidative activity of GTC --- p.55 / Chapter 2.5.4 --- Antioxidative activities of individual epicatechin isomers --- p.55 / Chapter 2.5.5 --- Thermal loss of GTC --- p.60 / Chapter 2.6 --- Discussion --- p.62 / Chapter 2.6.1 --- Contribution of catechins to the antioxidative effects of tea ethanol extracts --- p.62 / Chapter 2.6.2 --- Antioxidaitve activities of different types of teas --- p.62 / Chapter 2.6.3 --- Proposed mechanisms for the relative activity of epicatechin isomers --- p.63 / Chapter 2.6.4 --- Loss of BHT via volatilization --- p.66 / Chapter 2.6.5 --- Potential of tea catechins as food antioxidants --- p.67 / Chapter 2.6.5.1 --- Safety of GTC --- p.67 / Chapter 2.6.5.2 --- Solubility of GTC --- p.68 / Chapter 2.6.5.3 --- Effects of GTC on food quality --- p.68 / Chapter CHAPTER 3 --- INHIBITORY EFFECTS OF GTC AND EPICATECHIN ISOMERS ON IN VITRO CU2+-MEDIATED LDL OXIDATION --- p.70 / Chapter 3.1 --- Introduction --- p.70 / Chapter 3.1.1 --- Mechanisms of LDL oxidation --- p.71 / Chapter 3.1.1.1 --- Nature and sources of oxidants underlying LDL oxidation --- p.71 / Chapter 3.1.1.2 --- Structural changes of ox-LDL --- p.72 / Chapter 3.1.2 --- Biological effects of ox-LDL --- p.74 / Chapter 3.1.3 --- Antioxidants and atherosclerosis --- p.76 / Chapter 3.2 --- Objectives --- p.78 / Chapter 3.3 --- Materials and methods --- p.79 / Chapter 3.3.1 --- LDL isolation --- p.79 / Chapter 3.3.2 --- LDL oxidation --- p.79 / Chapter 3.3.3 --- Thiobarbituric acid-reactive substance (TBARS) assay --- p.80 / Chapter 3.3.4 --- Lipid analysis --- p.80 / Chapter 3.3.5 --- Statistics --- p.81 / Chapter 3.4 --- Results --- p.82 / Chapter 3.4.1 --- Protective effects of GTC against LDL oxidation --- p.82 / Chapter 3.4.2 --- Varying protective effects of individual epicatechin isomers --- p.82 / Chapter 3.4.3 --- Protective effects of GTC against oxidative degradation of PUFAs in LDL --- p.86 / Chapter 3.5 --- Discussion --- p.88 / Chapter 3.5.1 --- Tea catechins as anti-atherogenic agents --- p.88 / Chapter 3.5.2 --- Mechanisms of the protective effects of tea catechins against Cu2+-induced LDL oxidation --- p.88 / Chapter 3.5.3 --- Relative antioxidative activities of epicatchin isomers --- p.89 / Chapter 3.5.4 --- Absorption of tea catechins --- p.90 / Chapter 3.5.5 --- Pro-oxidant activities of tea catechins --- p.91 / Chapter CHAPTER 4 --- HYPOLIPIDEMIC ACTIVITY OF GTC --- p.93 / Chapter 4.1 --- Introduction --- p.93 / Chapter 4.1.1 --- High serum cholesterol as a risk factor of CHD --- p.93 / Chapter 4.1.2 --- Serum TG and CHD --- p.94 / Chapter 4.1.3 --- Hypolipidemic effect of tea --- p.95 / Chapter 4.1.4 --- Hamster as an animal model of cholesterol metabolism --- p.96 / Chapter 4.2 --- Objectives --- p.97 / Chapter 4.3 --- Materials and methods --- p.98 / Chapter 4.3.1 --- Animals --- p.98 / Chapter 4.3.2 --- Experiment 1 --- p.98 / Chapter 4.3.3 --- Experiment 2 --- p.100 / Chapter 4.3.4 --- Experiment 3 --- p.101 / Chapter 4.3.5 --- "Serum lipid, lipoprotein and apolipoprotein determinations" --- p.101 / Chapter 4.3.6 --- Lipid analysis of liver and carcass --- p.102 / Chapter 4.3.7 --- Analysis of fecal lipid content --- p.102 / Chapter 4.3.8 --- Determination of hepatic cholesterol content --- p.103 / Chapter 4.3.9 --- Assay of fatty acid synthase activity --- p.105 / Chapter 4.3.10 --- Statistics --- p.105 / Chapter 4.4 --- Results --- p.106 / Chapter 4.4.1 --- Growth and food intake --- p.106 / Chapter 4.4.2 --- Effects of different levels of dietary GTC on serum TG and cholesterol --- p.106 / Chapter 4.4.3 --- Time course study of the hypolipidemic effects of dietary GTC --- p.109 / Chapter 4.4.4 --- Effects of GTWE on serum lipid and apolipoprotein profiles --- p.113 / Chapter 4.4.5 --- "Effects of dietary GTC on hepatic TG, FFA and cholesterol contents" --- p.113 / Chapter 4.4.6 --- "Effects of dietary GTC on carcass TG, FFA and cholesterol contents" --- p.118 / Chapter 4.4.7 --- Effects of dietary GTC on fatty acid synthase activity --- p.118 / Chapter 4.4.8 --- Effects of dietary GTC on fecal lipids content --- p.118 / Chapter 4.5 --- Discussion --- p.120 / Chapter 4.5.1 --- Hypolipidemic effect of GTC --- p.120 / Chapter 4.5.2 --- Effects of GTC on serum apolipoproteins --- p.120 / Chapter 4.5.3 --- Implication of GTC intake in humans --- p.121 / Chapter 4.5.4 --- Mechanisms for the hypolipidemic activity of GTC --- p.122 / Chapter 4.5.5 --- Reduction in hepatic TG and FFA contents in GTC-fed hamsters --- p.123 / Chapter 4.5.6 --- Suppression of body lipid accumulation by dietary GTC --- p.124 / Chapter 4.5.7 --- Mechanisms for the hypocholesterolemic activity of GTC --- p.124 / Chapter CHAPTER 5 --- CONCLUSIONS --- p.126 / REFERENCES --- p.129
25

Neuroprotective effect of green tea extracts

Cheng, Tak-him, Terence. January 2008 (has links)
Thesis (M. Phil.)--University of Hong Kong, 200 . / Includes bibliographical references (leaf 161-172) Also available in print.
26

A Molecular Dynamics Study on the Interaction of Tea Catechins and Theaflavins with Biological Membranes

Sirk, Timothy Wayne 07 May 2009 (has links)
Molecular dynamics simulations were performed to study the interactions of bioactive catechins and theaflavins commonly found in tea with lipid bilayers, as a model for cell membranes. Previously, multiple experimental studies rationalized the anticarcinogenic, antibacterial, and other beneficial effects of these compounds in terms of physicochemical molecular interactions with cell membranes. To contribute toward understanding the molecular role of tea polyphenols on the structure of cell membranes, simulation results are presented for seven catechins and three theaflavins in lipid bilayer systems which are both pure (POPC) and representative of HepG2 cancer cells (POPC and POPE). Our simulations show that the catechins and theaflavins evaluated have a strong affinity for the lipid bilayer \textit{via} hydrogen bonding to the bilayer surface, with many of the catechins able to penetrate beneath the surface. Epigallocatechin-gallate (EGCG) and Theaflavin-3,3'-digallate showed the strongest interaction with the lipid bilayers based on the number of hydrogen bonds formed with lipid headgroups. The simulations also provide insight into the functional characteristics of the tea compounds that distinguish them as effective compounds to potentially alter the lipid bilayer properties. The results on the hydrogen-bonding effects may contribute to a better understanding of proposed multiple molecular mechanisms of the action of catechins and theaflavins in microorganisms, cancer cells, and tissues. / Ph. D.
27

The study of feasibility of green tea treatment on fetus: from chemistry to treatment. / CUHK electronic theses & dissertations collection

January 2005 (has links)
Hypoxia and reperfusion can result in many pathological complications in the fetus including retinopathy, ischemic encephalopathy and even stillbirth. The adverse effects are due to excess production of free radicals that attack vital bio-molecules such as DNA and enzymes. Antioxidant treatment may be a way to alleviate oxidative stress. Green tea is a source of antioxidants. It contains polyphenols mainly catechins, that possess high reducing power and low toxicity. Major catechin compounds in green tea are (+)-catechin (C), (-)-epicatechin (EC, (-)-gallocatechin (GC), (-)-epigallocatechin (EGC), (-)-catechin gallate (CG), (-)-epicatechin gallate (ECG), (-)-gallocatechin gallate (GCG) and (-)-epigallocatechin gallate (EGCG). Accordingly, catechins may be ideal agents for antioxidant treatment of the fetus exposed to hypoxia during pregnancy. / In the animal experiments, rat mothers, at the 15.5th gestation day, were intragastrically administrated a single dose of green tea extract. The pharmacokinetic profiles of catechins in maternal plasma, whole embryos and embryonic organs were investigated. The catechins GC, ECG, C, EC, were found to exhibit non-linear capacity limited pharmacokinetic behaviour implying their metabolism or absorption was saturated. Catechin gallates, EGCG and ECG, appeared to exhibit enterohepatic re-circulation behaviour. Peak time was about 1 hour for both groups of catechins; the half life of the catechin group was about 1 hour while that of EGCG and ECG was about 3.7 hours. EC, EGC and EGCG were the dominant compounds present in plasma. All catechins exhibited a consecutive one-compartment model in the embryo, where EGCG, ECG, EGC and EC were dominant compounds and ECG had the highest penetrability. (Abstract shortened by UMI.) / In this study, pregnant rat dams were fed green tea extract in an attempt to raise catechin levels in the rat embryo in order to scavenge free radicals. To test this hypothetical application, we first established analytical methods to evaluate oxidative stress and catechins levels of the fetus in vivo. The methodologies included assaying F2-isoprostanes in cord blood and determining catechin levels in biological fluids and tissues. We further utilized these new sensitive analytical methods to investigate the pharmacokinetics of the catechins in maternal rat plasma, whole embryos and embryonic organs. Since no data has been previously reported on the toxic effects of catechins on embryos, we also tested the toxic effects of various concentrations of catechins on the developing embryonic features in embryo culture. / Chu Kai On. / "April 2005." / Advisers: Michael Scott Rogers; Chi Pui Pang. / Source: Dissertation Abstracts International, Volume: 67-01, Section: B, page: 0244. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (p. 208-241). / 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. / Abstract in English and Chinese. / School code: 1307.
28

Protective effect of green tea polyphenols on dinitrobenzene sulphonicacid (DNBS)-induced colitis in mice

Kopaniszen, Malgorzata. January 2008 (has links)
published_or_final_version / Pharmacology / Master / Master of Philosophy
29

Growth inhibition effects of green tea and epigallocatechin gallate inbladder tumors

Chen, Jie, Jack, 陳杰 January 2003 (has links)
published_or_final_version / Pharmacology / Doctoral / Doctor of Philosophy
30

Antioxidative and vascular relaxing effects of black tea theaflavins. / CUHK electronic theses & dissertations collection

January 2003 (has links)
by Su Ya Lun. / "August 2003." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (p. 163-181). / 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.

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