Evaluation of the anti-diabetic activities of non-starch polysaccharides extracted from the fruiting body of Hericium erinaceus.

by Li Chi Yeung.Thesis submitted in: November 2004.Thesis (M.Phil.)--Chinese University of Hong Kong, 2005.Includes bibliographical references (leaves 151-176).Abstracts in English and Chinese.Thesis Committee --- p.iAcknowledgement --- p.iiAbstract (English Version) --- p.iiiAbstract (Chinese Version) --- p.vContent Page --- p.viiList of Tables --- p.xiiiList of Figures --- p.xvAbbreviation --- p.xviiChapter Chapter 1 --- Introduction --- p.1Chapter 1.1 --- Diabetes Mellitus --- p.1Chapter 1.1.1 --- Epidemiology --- p.1Chapter 1.1.2 --- Economic Impact --- p.3Chapter 1.2 --- "Digestion, Absorption and Metabolism of Carbohydrates" --- p.4Chapter 1.2.1 --- Carbohydrate Digestion --- p.4Chapter 1.2.2 --- Carbohydrate Absorption --- p.6Chapter 1.2.3 --- Insulin Secretion --- p.6Chapter 1.3 --- Pathophysiology of Diabetes Mellitus --- p.7Chapter 1.3.1 --- Insulin-Dependent Diabetes Mellitus (lDDM) --- p.7Chapter 1.3.1.1 --- Genetics --- p.8Chapter 1.3.1.2 --- Autoimmunity --- p.9Chapter 1.3.2 --- Non-Insulin-Dependent Diabetes Mellitus (NlDDM) --- p.11Chapter 1.3.2.1 --- Insulin Resistance --- p.11Chapter 1.3.2.2 --- Impaired Insulin Secretion --- p.14Chapter 1.4 --- Management of Diabetes Mellitus --- p.15Chapter 1.4.1 --- Sulfonylureas --- p.15Chapter 1.4.2 --- Biguanides --- p.16Chapter 1.4.3 --- Problems Encountered in the Management of Diabetes --- p.16Chapter 1.4.4 --- Role of Dietary Fiber in the Management of Diabetes Mellitus --- p.18Chapter 1.4.4.1 --- Dietary Fiber and Gastric Emptying Time --- p.19Chapter 1.4.4.2 --- Dietary Fiber and Glucose Absorption in Small Intestine --- p.20Chapter 1.4.5 --- Other Natural Products used for Diabetes Treatment…… --- p.22Chapter 1.5 --- Mushrooms --- p.22Chapter 1.5.1 --- The Definition of Mushrooms --- p.23Chapter 1.5.2 --- Nutritional Values of Mushrooms --- p.24Chapter 1.5.3 --- Production of Mushrooms --- p.25Chapter 1.6 --- Medicinal (Antidiabetic) Properties of Mushrooms --- p.28Chapter 1.6.1 --- Ganoderma lucidum --- p.29Chapter 1.6.2 --- Tremella aurantia --- p.33Chapter 1.6.3 --- Auricularia auricula --- p.36Chapter 1.6.4 --- Grifola frondosa --- p.37Chapter 1.7 --- Medicinal Uses of Hericium erinaceus --- p.39Chapter 1.7.1 --- HeLa Cell Proliferation Inhibitors --- p.39Chapter 1.7.2 --- Induction of Growth of Nerve Cells --- p.42Chapter 1.7.3 --- Antitumour Activity --- p.42Chapter 1.7.4 --- Antidiabetic Effect --- p.43Chapter 1.8 --- Objectives --- p.45Chapter Chapter 2 --- Materials and Methods --- p.46Chapter 2.1 --- Extraction of Polysaccharides from the Fruiting Body of H. erinaceus --- p.46Chapter 2.1.1 --- Small-scale Extraction --- p.46Chapter 2.1.2 --- Large-scale Extraction --- p.47Chapter 2.2 --- Physico-Chemical Characterization of HE-polysaccharides --- p.52Chapter 2.2.1 --- Carbohydrate Content: Phenol-Sulfuric Acid Method --- p.52Chapter 2.2.2 --- Protein Content: Lowry Assay --- p.52Chapter 2.2.3 --- Uronic Acid Content --- p.53Chapter 2.2.4 --- Molecular Weight Determination by High Pressure Liquid Chromatography (HPLC) --- p.55Chapter 2.2.5 --- Determination of Monosaccharide Composition of Non-Starch Polysaccharides by Gas Chromatography (GC) --- p.56Chapter 2.2.5.1 --- Acid Depolymerisation --- p.56Chapter 2.2.5.2 --- Neutral Sugar Derivatisation --- p.56Chapter 2.2.5.3 --- Determination of Neutral Sugar Composition by Gas Chromatography (GC) --- p.57Chapter 2.2.6 --- Structural Study of Polysaccharides by Methylation --- p.59Chapter 2.2.6.1 --- Preparation of dry Dimethyl Sulfoxide (DMSO) --- p.59Chapter 2.2.6.2 --- Preparation of Methylsulfinyl Methyl Sodium (CH3SOCH2-Na+) from the dry DMSO and Sodium Hydride --- p.59Chapter 2.2.6.3 --- Methylation Procedure --- p.60Chapter 2.2.6.4 --- Preparation of Partially Methylated Alditol Acetates (PMAAs) --- p.61Chapter 2.2.6.5 --- Analysis of the PMAAs by GC --- p.62Chapter 2.2.7 --- The Measurement of Viscosity --- p.62Chapter 2.3 --- In vitro Hypoglycemic Tests of HE-Polysaccharides --- p.64Chapter 2.3.1 --- Glucose Dialysis Retardation Index (GDRl) --- p.64Chapter 2.3.1.1 --- Experimental Setup --- p.64Chapter 2.3.1.2 --- Measurement of Glucose in the Dialysate --- p.65Chapter 2.3.2 --- Inhibition of Amylolysis --- p.66Chapter 2.3.2.1 --- Experimental Setup --- p.66Chapter 2.3.2.2 --- Measurement of Maltose in the Dialysate --- p.66Chapter 2.4 --- In vivo Hypoglycemic Evaluation of HE-Polysaccharides --- p.67Chapter 2.4.1 --- Oral Glucose Tolerance Test (OGTT) --- p.67Chapter 2.4.2 --- Induction of Type l Diabetes in Normal BALB/c Mice --- p.69Chapter 2.4.2.1 --- lnduction Protocol --- p.69Chapter 2.4.2.2 --- Measurement of Plasma Glucose Level --- p.70Chapter 2.4.3 --- Hypoglycemic Test on Normal and Diabetic BALB/c Mice --- p.71Chapter 2.4.4 --- Measurement of Insulin Level by Enzyme-Linked Immunoadsorbent Assay (ELlSA) --- p.72Chapter 2.4.4.1 --- Plasma Samples used in ELlSA --- p.72Chapter 2.4.4.2 --- Assay Procedure --- p.73Chapter 2.5 --- Statistical Evaluation --- p.74Chapter Chapter 3 --- Results and Discussion --- p.75Chapter 3.1 --- Yield of Polysaccharides extracted from H. erinaceus --- p.75Chapter 3.2 --- Physico-chemical Properties of HE Polysaccharides --- p.79Chapter 3.2.1 --- "Carbohydrate, Protein and Uronic Acid Content" --- p.79Chapter 3.2.2 --- Monosaccharide Compositions --- p.83Chapter 3.2.3 --- Molecular Weight of the HE polysaccharides --- p.85Chapter 3.2.4 --- Structure of HE polysaccharides --- p.90Chapter 3.2.5 --- Conclusion for the Physico-chemical Properties of HE-Polysaccharides --- p.96Chapter 3.2.6 --- Viscosity of HE Polysaccharides --- p.99Chapter 3.3 --- In vitro Study of the Hypoglycemic Effect of HE-Polysaccharides --- p.101Chapter 3.3.1 --- Glucose Dialysis Retardation Index (GDRl) --- p.101Chapter 3.3.2 --- Inhibition of α-Amylase Activity --- p.105Chapter 3.4 --- In vivo Hypoglycemic Evaluation of HE-Polysaccharides --- p.109Chapter 3.4.1 --- In vivo Oral Glucose Tolerance Test (OGTT) in Normal Mice --- p.109Chapter 3.4.1.1 --- Oral Glucose Tolerance Test --- p.109Chapter 3.4.1.2 --- Effect of Change of Viscosity of HE Polysaccharide in the Gl Tract of Mice --- p.114Chapter 3.4.2 --- Establishment of a Diabetic Murine Model --- p.120Chapter 3.4.3 --- Hypoglycemic Activity of HE-polysaccharides in Normal Mice --- p.123Chapter 3.4.4 --- Hypoglycemic Activity of HE-polysaccharides in Diabetic Mice --- p.126Chapter 3.4.5 --- Change of Plasma Insulin Level in the Hypoglycemic Test --- p.132Chapter 3.4.6 --- Comparison of Hypoglycemic Activity of HE-Polysaccharides in Normal and Diabetic mice --- p.139Chapter 3.4.6.1 --- Severity of Diabetic Conditions lnduced --- p.139Chapter 3.4.6.2 --- Change in Insulin Secretion --- p.140Chapter 3.4.6.3 --- Glucose Transporter --- p.140Chapter 3.5 --- Other Factors that Affect in vivo Hypoglycemic Activity of the HE-polysaccharides --- p.141Chapter 3.5.1 --- Route of Administration: Oral Feeding and Intraperitoneal Injection --- p.141Chapter 3.5.2 --- Molecular Mechanisms of Hypoglycemic Activity --- p.142Chapter 3.5.3 --- Glucose Toxicity --- p.144Chapter 3.5.3.1 --- Insulin Resistance --- p.144Chapter 3.5.3.2 --- Impaired Insulin Secretion --- p.145Chapter Chapter 4 --- Conclusions and Future Works --- p.147References --- p.15