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Orientador: Márcia Regina de Moura[UNESP] Aouada / Resumo: O presente trabalho é uma investigação das propriedades de embalagens ativas beneficiadas com a substância Curcuma longa derivada do açafrão. Essa substância apresenta propriedade antioxidativa, que tem despertado interesse da indústria de fármacos, e que vem sendo bastante utilizada na indústria de alimentos como corante natural e tempero. O propósito do trabalho é a síntese e caracterização da solução base para a produção dos filmes ativos contendo composição inédita de Curcuma longa, carboximetilcelulose (CMC) e nanopartículas de quitosana (NSQ). A produção de filmes e revestimentos poliméricos para a indústria alimentícia é alvo de constantes pesquisas, devido a necessidade de diminuir o volume de embalagens plásticas descartadas e otimizar as propriedades e validade dos alimentos. Dentre a imensa variedade de polímeros a carboximetilcelulose é muito favorável a produção de filmes pelo seu caráter atóxico, biodegradabilidade e baixo custo. A quitosana assim como o CMC é uma substância com ampla aplicação nos campos da farmacologia, tecnologia de biomateriais, biomedicina, agricultura e indústrias cosmética e alimentícia. Os filmes foram produzidos com carboximetilcelulose, nanopartículas de quitosana e Curcuma longa de acordo com o método “casting”. As nanopartículas foram obtidas pelo método de gelificação ionotrópica. Foram realizadas análises: térmicas, mecânicas, permeabilidade ao vapor de água, espectroscopia do infra- vermelho, ângulo de contato, microscopia eletrôn... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The present work is an investigation of the properties of active packaging benefited with the substance Curcuma longa derived from saffron. This substance has antioxidative properties, which has aroused interest in the drug industry and is widely used in the food industry as a natural dye and seasoning. The purpose of the work is the synthesis and characterization of the base solution for the production of active films containing novel composition of Curcuma longa, carboxymethylcellulose (CMC) and chitosan nanoparticles (NSQ). The production of films and polymer coatings for the food industry is the subject of constant research, due to the need to reduce the volume of discarded plastic packaging and to optimize the properties and validity of the food. Among the immense variety of polymers the carboxymethylcellulose is very favorable the production of films by its nontoxic character, biodegradability and low cost. Chitosan as well as CMC is a substance with broad application in the fields of pharmacology, biomaterial technology, biomedicine, agriculture and cosmetic and food industries. The films were produced with carboxymethylcellulose, chitosan nanoparticles and Curcuma longa according to the casting method. The nanoparticles were obtained by ionotropic gelation. Thermal, mechanical, water vapor permeability, infrared spectroscopy, contact angle and scanning electron microscopy were performed. The nanoparticles were characterized by zeta potential and presented spherical sh... (Complete abstract click electronic access below) / Mestre

Cheung Lai Ming. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 153-161). / Abstracts in English and Chinese. / THESIS COMMITTEE --- p.i / ACKNOWLEDGEMENTS --- p.ii / ABSTRACT --- p.iii / ABSTRACT (Chinese version) --- p.v / CONTENTS --- p.vi / LIST OF TABLES --- p.xi / LIST OF FIGURES --- p.xiii / LIST OF ABBREVIATIONS --- p.xv / Chapter CHAPTER ONE: --- INTRODUCTION --- p.1 / Chapter 1.1 --- Free radical --- p.2 / Chapter 1.1.1 --- Definition --- p.2 / Chapter 1.1.2 --- Reaction mechanism --- p.3 / Chapter 1.1.3 --- Sources of oxygen reactive species --- p.4 / Chapter 1.1.3.1 --- Enzymes --- p.4 / Chapter 1.1.3.2 --- The auto-oxidation of small molecules --- p.4 / Chapter 1.1.3.3 --- Haem proteins --- p.5 / Chapter 1.1.3.4 --- Endoplasmic reticulum sources --- p.5 / Chapter 1.1.3.5 --- Mitochondrial sources --- p.5 / Chapter 1.1.3.6 --- Nucleus --- p.6 / Chapter 1.1.4 --- Lipid peroxidation --- p.6 / Chapter 1.1.4.1 --- Initiation of lipid peroxidation --- p.7 / Chapter 1.1.4.2 --- Propagation of lipid peroxidation --- p.8 / Chapter 1.1.4.3 --- Products of lipid peroxidation --- p.9 / Chapter 1.1.5 --- Human diseases associated with free radicals --- p.10 / Chapter 1.2 --- Antioxidants --- p.12 / Chapter 1.2.1 --- Definition --- p.12 / Chapter 1.2.2 --- Defence against free radical damage --- p.13 / Chapter 1.2.2.1 --- Catalytic free radical removal --- p.13 / Chapter 1.2.2.2 --- Free radical scavenging --- p.14 / Chapter 1.2.2.3 --- Removal of catalytic iron and copper ions --- p.14 / Chapter 1.2.3 --- Synthetic vs. natural antioxidant --- p.15 / Chapter 1.2.3.1 --- Synthetic antioxidants --- p.15 / Chapter 1.2.3.2 --- Natural antioxidants --- p.16 / Chapter 1.3 --- Measurement of antioxidant activity --- p.17 / Chapter 1.3.1 --- Loss of substrate --- p.17 / Chapter 1.3.1.1 --- Beta-carotene bleaching method --- p.17 / Chapter 1.3.2 --- Measurement of free radical scavenging --- p.17 / Chapter 1.3.2.1 --- "Scavenging of 1,1-diphenyl-2-picrylhydrazyl radical (DPPH´Ø)" --- p.17 / Chapter 1.3.2.2 --- Superoxide scavenging --- p.18 / Chapter 1.3.2.3 --- Hydrogen peroxide scavenging --- p.18 / Chapter 1.3.2.4 --- Hydroxyl radical scavenging --- p.19 / Chapter 1.3.2.5 --- Peroxyl radical --- p.19 / Chapter 1.3.3 --- Measurement of end product --- p.21 / Chapter 1.3.3.1 --- Diene conjugation --- p.21 / Chapter 1.3.3.2 --- Light emission --- p.21 / Chapter 1.3.3.3 --- The thiobarbituric acid (TBA) test --- p.22 / Chapter 1.3.4 --- Low-density lipoprotein oxidation --- p.22 / Chapter 1.4 --- Phenolic antioxidant --- p.24 / Chapter 1.4.1 --- Chemistry --- p.24 / Chapter 1.4.2 --- Mechanism of action of phenolic antioxidants --- p.25 / Chapter 1.4.3 --- Isolation and characterization --- p.25 / Chapter 1.4.3.1 --- Extraction --- p.25 / Chapter 1.4.3.2 --- Analysis of phenolic compounds --- p.27 / Chapter 1.4.3.2.1 --- Colorimetric method --- p.27 / Chapter 1.4.3.2.2 --- Enzymatic method --- p.28 / Chapter 1.4.3.2.3 --- Paper chromatography --- p.28 / Chapter 1.4.3.2.4 --- Thin-layer chromatography --- p.29 / Chapter 1.4.3.2.5 --- UV-Vis absorption spectroscopy --- p.29 / Chapter 1.4.3.2.6 --- High-performance liquid chromatography --- p.30 / Chapter 1.4.4 --- Natural sources of phenolic antioxidants --- p.31 / Chapter 1.4.4.1 --- Olive oil --- p.31 / Chapter 1.4.4.2 --- Berry --- p.32 / Chapter 1.4.4.3 --- Cherry --- p.32 / Chapter 1.4.4.4 --- Red wine --- p.32 / Chapter 1.4.4.5 --- Herb --- p.33 / Chapter 1.4.4.6 --- Vegetables --- p.33 / Chapter 1.5 --- Mushroom Sample --- p.34 / Chapter 1.5.1 --- Pleurotus tuber-regium --- p.34 / Chapter 1.5.2 --- Lentinus edodes --- p.34 / Chapter 1.5.3 --- Volvariella volvacea --- p.35 / Chapter 1.5.4 --- Antioxidants in fungi or mushroom --- p.37 / Chapter 1.5.5 --- Phenolic compounds in mushrooms --- p.39 / Chapter 1.6 --- Objectives --- p.42 / Chapter CHAPTER TWO: --- MATERIALS AND METHODS --- p.43 / Chapter 2.1 --- Sample Collection --- p.43 / Chapter 2.2 --- Sample Preparation --- p.43 / Chapter 2.3 --- Moisture Content --- p.43 / Chapter 2.4 --- Solvent Extraction --- p.44 / Chapter 2.4.1 --- Scheme I (Aqueous extraction only) --- p.44 / Chapter 2.4.2 --- Scheme II (Methanol and water extraction) --- p.45 / Chapter 2.4.3 --- Scheme III (Differential solvent extraction) --- p.46 / Chapter 2.4.4 --- Scheme IV (Scaled-up extraction) --- p.47 / Chapter 2.5 --- Antioxidant activity assays --- p.50 / Chapter 2.5.1 --- Beta-carotene bleaching method --- p.50 / Chapter 2.5.2 --- "Scavenging activity on 1,1 -diphenyl-2-picrylhydrazyl radicals" --- p.51 / Chapter 2.5.3 --- Assay for erythrocyte hemolysis --- p.51 / Chapter 2.5.4 --- Assay of lipid peroxidation using rat brain --- p.52 / Chapter 2.5.5 --- LDL oxidation (TBARS) --- p.53 / Chapter 2.5.5.1 --- LDL Isolation --- p.53 / Chapter 2.5.5.2 --- Calculation of density --- p.54 / Chapter 2.5.5.3 --- Lowry Method for Protein Determination --- p.55 / Chapter 2.5.5.4 --- Reagents for TBARS assay --- p.55 / Chapter 2.5.5.5 --- TBARS formation --- p.56 / Chapter 2.6 --- Determination of total polyphenolic compounds --- p.56 / Chapter 2.7 --- Fractionation --- p.57 / Chapter 2.7.1 --- Fractionation of the methanol crude extracts obtained under reflux by solvent --- p.57 / Chapter 2.7.2 --- Fractionation of boiling water crude extracts by ultrafiltration --- p.57 / Chapter 2.8 --- Crude Protein Content (Kjeldahl method) --- p.58 / Chapter 2.9 --- Total carbohydrate content --- p.59 / Chapter 2.10 --- Thin-layer chromatography --- p.59 / Chapter 2.11 --- High performance liquid chromatography --- p.60 / Chapter 2.11.1 --- Analysis of methanol fractions --- p.60 / Chapter 2.11.2 --- Analysis of water fractions --- p.61 / Chapter 2.12 --- Liquid chromatography-Mass spectrometry --- p.61 / Chapter 2.12.1 --- Liquid chromatography --- p.61 / Chapter 2.12.2 --- Mass spectrometric analysis --- p.62 / Chapter 2.13 --- Data analysis --- p.62 / Chapter CHAPTER THREE: --- RESULTS AND DISCUSSION --- p.63 / Chapter 3.1 --- Mushroom sample --- p.63 / Chapter 3.2 --- Extraction scheme I --- p.65 / Chapter 3.2.1 --- Antioxidant activity --- p.65 / Chapter 3.2.1.1 --- Effect of extraction temperature --- p.65 / Chapter 3.2.1.2 --- Effect of concentration of extracts --- p.66 / Chapter 3.3 --- Extraction scheme II --- p.69 / Chapter 3.3.1 --- Antioxidant activity --- p.69 / Chapter 3.3.1.1 --- Effect of extraction temperature --- p.69 / Chapter 3.3.1.2 --- Effect of concentration of extracts --- p.72 / Chapter 3.3.1.3 --- Effect of solvent --- p.72 / Chapter 3.4 --- Extraction scheme III --- p.75 / Chapter 3.4.1 --- Extraction yield --- p.75 / Chapter 3.4.2 --- Total phenolic content --- p.76 / Chapter 3.4.3 --- Antioxidant activity --- p.80 / Chapter 3.4.3.1 --- Beta-carotene bleaching method --- p.80 / Chapter 3.4.3.1.1 --- Effect of extract concentration --- p.80 / Chapter 3.4.3.1.2 --- Relation between total phenolic content and antioxidant activity --- p.82 / Chapter 3.4.3.2 --- "Scavenging activity of 1,1 -diphenyl-2-picrylhydrazyl (DPPH) radical" --- p.85 / Chapter 3.4.3.3 --- Assay for erythrocyte hemolysis --- p.88 / Chapter 3.5 --- Extraction scheme IV --- p.91 / Chapter 3.5.1 --- Yield and Fractionation --- p.91 / Chapter 3.5.2 --- Chemical characterization of fractions --- p.93 / Chapter 3.5.2.1 --- Protein content --- p.93 / Chapter 3.5.2.2 --- Total carbohydrate content --- p.93 / Chapter 3.5.2.3 --- Total phenolic content --- p.94 / Chapter 3.5.3 --- Antioxidant activity --- p.99 / Chapter 3.5.3.1 --- Assay for lipid peroxidation of rat brain --- p.99 / Chapter 3.5.3.2 --- LDL oxidation --- p.118 / Chapter 3.5.4 --- Identification of antioxidant by chromatographic methods --- p.126 / Chapter 3.5.4.1 --- Thin-layer chromatography --- p.126 / Chapter 3.5.4.2 --- High-performance liquid chromatography --- p.132 / Chapter 3.5.4.3 --- Liquid chromatography-Mass spectrometry --- p.142 / Chapter CHAPTER FOUR: --- CONCLUSION --- p.148 / REFERENCES --- p.153 / RELATED PUBLICATION --- p.161

Choi, Man Wing. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 126-139). / Abstracts in English and Chinese. / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Antigen presenting cells (APC) in Immune systems --- p.1 / Chapter 1.1.1 --- Dendritic cells --- p.2 / Chapter 1.1.1.1 --- Differentiation of dendritic cells in mice --- p.2 / Chapter 1.1.1.2 --- Maturation of dendritic cells --- p.3 / Chapter 1.1.1.3 --- Stimulation and polarization of T cells stimulated by dendritic cells --- p.6 / Chapter 1.1.2 --- Monocyte and macrophage --- p.7 / Chapter 1.1.2.1 --- Differentiation of monocyte and macrophage in humans --- p.7 / Chapter 1.1.2.2 --- Changes involved in differentiation of monocytes into macrophages --- p.9 / Chapter 1.2 --- "Isolation, structure and activity of mushroom polysaccharides" --- p.13 / Chapter 1.2.1 --- Sources of mushroom polysaccharides --- p.13 / Chapter 1.2.2 --- Extraction methods --- p.14 / Chapter 1.2.3 --- Structure-Activity Relationship (SAR) of mushroom polysaccharides --- p.15 / Chapter 1.2.4 --- Previous studies on immunomodulatory effects of mushroom sclerotial polysaccharides --- p.18 / Chapter 1.3 --- Recognition of β-glucan by specific receptors --- p.20 / Chapter 1.3.1 --- Complement Receptor 3 (CR3) --- p.22 / Chapter 1.3.1.1 --- Introduction of CR3 --- p.22 / Chapter 1.3.1.2 --- Expressions of CR3 to recognize fungi --- p.22 / Chapter 1.3.2 --- Dectin-1 --- p.24 / Chapter 1.3.2.1 --- Introduction of Dectin-1 --- p.24 / Chapter 1.3.2.2 --- Structure of Full-length Dectin-1 --- p.26 / Chapter 1.3.2.2.1 --- Isoforms of Dectin-1 in Mice --- p.28 / Chapter 1.3.2.2.2 --- Isoforms of Dectin-1 in Humans --- p.28 / Chapter 1.3.2.3 --- Immune responses triggered by of Dectin-1 --- p.29 / Chapter 1.3.3 --- Toll-like 2 receptor (TLR2) --- p.31 / Chapter 1.3.3.1 --- Introduction of TLR2 --- p.31 / Chapter 1.3.3.2 --- Structure of TLR2 --- p.33 / Chapter 1.3.3.3 --- Immune responses triggered by TLR2 --- p.34 / Chapter 1.4 --- Research Objectives --- p.35 / Chapter Chapter 2 --- Materials and Methods --- p.38 / Chapter 2.1 --- Materials --- p.38 / Chapter 2.1.1 --- Mushroom sclerotia --- p.38 / Chapter 2.1.1.1 --- Polysaccharide extraction from mushroom sclerotia --- p.38 / Chapter 2.1.2 --- Antibodies and reagents --- p.41 / Chapter 2.1.3 --- Human acute leukocyte monocytic cell line and culture medium --- p.42 / Chapter 2.1.4 --- Preparation of murine bone marrow-derived immature dendritic primary cells (immature BMDCs) --- p.43 / Chapter 2.2 --- Methods --- p.45 / Chapter 2.2.1 --- Chemical Analysis --- p.45 / Chapter 2.2.1.1 --- Measurement of monosaccharide profile --- p.45 / Chapter 2.2.1.1.1 --- Acid depolymerisation --- p.45 / Chapter 2.2.1.1.2 --- Neutral sugar derivatization --- p.45 / Chapter 2.2.1.1.3 --- Gas chromatography (GC) --- p.46 / Chapter 2.2.1.2 --- Determination of total sugar by phenol-sulfuric acid method --- p.47 / Chapter 2.2.1.3 --- Determination of protein content by Lowry-Folin Method --- p.48 / Chapter 2.2.1.4 --- Size exclusion chromatography by high pressure liquid chromatography (HPLC) --- p.49 / Chapter 2.2.1.5 --- Endotoxin detection --- p.50 / Chapter 2.2.2 --- Measurement of Bioactivities --- p.51 / Chapter 2.2.2.1 --- Trypan blue exclusion assay --- p.51 / Chapter 2.2.2.2 --- MTT cell proliferation assay --- p.51 / Chapter 2.2.2.3 --- BrdU cell proliferation assay --- p.53 / Chapter 2.2.2.4 --- Expression of cell surface markers --- p.54 / Chapter 2.2.2.5 --- Phagocytosis / Endocytosis of FITC-labeled dextrans --- p.55 / Chapter 2.2.2.6 --- Nitric oxide production assay --- p.55 / Chapter 2.2.2.7 --- Reactive oxygen species production --- p.57 / Chapter 2.2.2.8 --- Determination of cytokine profile using cytokine antibody array --- p.58 / Chapter 2.2.2.9 --- Cell cycle analysis --- p.59 / Chapter 2.2.2.10 --- Expression of surface receptors --- p.60 / Chapter 2.2.2.11 --- Statistical analysis --- p.61 / Chapter Chapter 3 --- Results and Discussion --- p.61 / Chapter 3.1 --- Chemical characteristics of sclerotial polysaccharides --- p.61 / Chapter 3.1.1. --- The yield of sclerotial polysaccharides --- p.61 / Chapter 3.1.2 --- Total carbohydrate content of sclerotial polysaccharides --- p.65 / Chapter 3.1.3 --- Protein content of sclerotial polysaccharides --- p.66 / Chapter 3.1.4 --- Monosaccharide profiles of sclerotial polysaccharides from PR by gas chromatography (GC) --- p.66 / Chapter 3.1.5 --- Molecular weight of sclerotial polysaccharides from PR by size exclusion chromatography (SEC) --- p.69 / Chapter 3.1.6 --- Endotoxin test --- p.73 / Chapter 3.2 --- Immune responses for human monocytic cell line THP-1 --- p.74 / Chapter 3.2.1 --- MTT cell viability assay --- p.74 / Chapter 3.2.2 --- BrdU cell proliferation assay --- p.75 / Chapter 3.2.3 --- Change in cell morphology of THP-1 --- p.79 / Chapter 3.2.4 --- Phenotypic maturation of THP-1 --- p.81 / Chapter 3.2.5 --- Up-regulated phagocytic ability of THP-1 --- p.84 / Chapter 3.2.6 --- Increased nitrite production in THP-1 --- p.86 / Chapter 3.2.7 --- Production of reactive oxygen species --- p.88 / Chapter 3.2.8 --- Human cytokines profile array --- p.90 / Chapter 3.2.9 --- Cell cycle analysis --- p.93 / Chapter 3.2.10 --- Surface receptors expression --- p.95 / Chapter 3.2.11 --- Summary --- p.98 / Chapter 3.3 --- Immune responses for murine immature BMDCs --- p.102 / Chapter 3.3.1 --- Inhibition effects on murine immature BMDCs --- p.102 / Chapter 3.3.2 --- Change in cell morphology of murine immature BMDCs --- p.103 / Chapter 3.3.3 --- Phenotypic maturation of murine immature BMDCs --- p.105 / Chapter 3.3.4 --- Down-regulation of endocytosis in murine immature BMDCs --- p.106 / Chapter 3.3.5 --- Increased nitrite production --- p.109 / Chapter 3.3.6 --- Decreased expression of CD 11c in PRW-treated immature BMDCs --- p.109 / Chapter 3.3.7 --- Cytokine profile detection --- p.112 / Chapter 3.3.8 --- Surface receptors expression --- p.116 / Chapter 3.3.9 --- Summary --- p.119 / Chapter Chapter 4 --- Conclusion and future works --- p.123 / Appendix --- p.125 / References --- p.126

Guo, Cuixia. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 75-85). / Abstracts in English and Chinese. / Thesis committee --- p.ii / Abstract --- p.iii / 摘要 --- p.iv / Acknowledgment --- p.v / List of Tables --- p.vi / List of Figures --- p.vii / List of Abbreviations --- p.viii / Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Introduction to immune system --- p.1 / Chapter 1.2 --- Immune effecter cells --- p.1 / Chapter 1.2.1 --- Macrophage --- p.1 / Chapter 1.2.2 --- Dendritic Cells (DCs) --- p.5 / Chapter 1.3 --- Immunomodulatory and antitumor activities of mushrooms --- p.8 / Chapter 1.3.1 --- Introduction to mushroom --- p.11 / Chapter 1.3.2 --- Mushroom polysaccharides --- p.11 / Chapter 1.3.3 --- Mushroom β-glucan --- p.14 / Chapter 1.4 --- The receptors for polysaccharides associated with immune effecter cells --- p.16 / Chapter 1.4.1 --- CR3 --- p.16 / Chapter 1.4.2 --- Dectin-1 --- p.18 / Chapter 1.4.3 --- TLR2 --- p.19 / Chapter 1.5 --- Nuclear factor-kappa B (NF-kB) activation --- p.19 / Chapter 1.6 --- Previous studies on mushroom sclerotium --- p.20 / Chapter 1.6.1 --- Pleurotus tuber-regium (PT) --- p.20 / Chapter 1.6.2 --- Polyporus rhinocerus (PR) --- p.21 / Chapter 1.7 --- Objectives --- p.21 / Chapter 2. --- Materials and Methods --- p.23 / Chapter 2.1 --- Materials --- p.23 / Chapter 2.1.1 --- Mushroom sclerotia --- p.23 / Chapter 2.1.2 --- Animal --- p.23 / Chapter 2.1.3 --- Cell lines --- p.24 / Chapter 2.2 --- Methods --- p.24 / Chapter 2.2.1 --- Hot water extraction --- p.24 / Chapter 2.2.2 --- Measurement of monosaccharide profile --- p.25 / Chapter 2.2.2.1 --- Acid depolymerization --- p.25 / Chapter 2.2.2.2 --- Neutral sugar derivatization --- p.25 / Chapter 2.2.2.3 --- Gas chromatography (GC) --- p.26 / Chapter 2.2.3 --- Determination of molecular weight by size exclusion chromatography (SEC) --- p.27 / Chapter 2.2.4 --- Determination of total sugar by phenol-sulfuric acid method --- p.28 / Chapter 2.2.5 --- Determination of protein content by Lowry-Folin method --- p.28 / Chapter 2.2.6 --- Detection of endotoxin --- p.29 / Chapter 2.2.7 --- Immunomodulatory activities induced in RAW264.7 cell line and murine peritoneal macrophages (PMs) --- p.30 / Chapter 2.2.7.1 --- Isolation of murine peritoneal macrophages (PMs) --- p.30 / Chapter 2.2.7.2 --- Detection of cell surface antigens on RAW 264.7 cells and PMs --- p.30 / Chapter 2.2.7.3 --- Phagocytic uptake --- p.31 / Chapter 2.2.7.4 --- Reactive Oxygen Species (ROS) generation --- p.32 / Chapter 2.2.7.5 --- Nitric Oxide (NO) production --- p.32 / Chapter 2.2.7.6 --- Inducible Nitric Oxide Synthase (iNOS) expression --- p.32 / Chapter 2.2.7.6.1 --- Cell lysates preparation --- p.33 / Chapter 2.2.7.6.2 --- Determination of protein concentrations --- p.33 / Chapter 2.2.7.6.3 --- Western blot --- p.34 / Chapter 2.2.7.7 --- Tumor Necrosis Factor-alpha (TNF-α) production --- p.36 / Chapter 2.2.8 --- DC cell marker determination --- p.37 / Chapter 2.2.9 --- Nuclear factor kappa B (NF-kB) activation --- p.37 / Chapter 2.2.10 --- Determination of the expression of existing cell surface β-glucan receptors --- p.37 / Chapter 2.2.11 --- Statistical methods --- p.38 / Chapter 3. --- Results --- p.39 / Chapter 3.1 --- Yield and chemical composition of mushroom sclerotial polysaccharides --- p.39 / Chapter 3.2 --- Endotoxin examination --- p.41 / Chapter 3.3 --- Monosaccharide profiles of PTW and PRW by GC --- p.41 / Chapter 3.4 --- Molecular weight profile by size exclusion chromatography (SEC) --- p.43 / Chapter 3.5 --- Immunomodulatory activities induced in RAW264.7 cells and murine peritoneal macrophages (PMs) --- p.46 / Chapter 3.5.1 --- Detection of cell surface antigens on RAW 264.7 cells and PMs --- p.46 / Chapter 3.5.2 --- Phagocytic uptake --- p.49 / Chapter 3.5.3 --- ROS generation --- p.53 / Chapter 3.5.4 --- NO production --- p.56 / Chapter 3.5.5 --- iNOS expression --- p.59 / Chapter 3.5.6 --- TNF-α production --- p.60 / Chapter 3.5.7 --- Morphological changes of cells --- p.62 / Chapter 3.5.8 --- DC cell marker determination --- p.64 / Chapter 3.6 --- Receptors expression on RAW 264.7 cells and PMs --- p.66 / Chapter 3.7 --- NF-kB activation --- p.68 / Chapter 3.8 --- Discussion --- p.70 / Chapter 4. --- Conclusions and Future Works --- p.73 / Chapter 5. --- References --- p.75

No description available.

This thesis investigates whether fats, akin to other taste stimuli, exhibit sensory properties such as mixture interactions. In order to determine gustatory, rather than tactile or olfactory effects, viscosity-controlled emulsions of deodorised oils were used as the base to which taste stimuli were incorporated and presented to a panel of trained assessors. In preliminary qualitative assessments, panellists described the 10% olive oil emulsion as saltier, stronger, fattier and having a more lingering aftertaste than the non-oil control, suggesting that oil modulates taste duration as well influencing taste intensity and/or perceived quality. Panellists were unable to rate the oil/fat taste per se with any degree of certainty hence further experiments examined the effect of oil on the perception of taste mixtures. In mixture interaction experiments, the addition of oil did not result in mixture suppression or enhancement for sweet, salty, sour or bitter while it significantly enhanced umami. To determine the locus of interaction, when MSG and oil were presented to each side of the tongue separately, the enhancement effect disappeared indicating a peripheral mechanism of interaction, similar to the attenuation of chilli burn by oil. In contrast, suprathreshold sucrose sweetness was enhanced by the contralateral presentation of oil, indicating sensory processing at a higher locus. Furthermore, the addition of oil significantly reduced bitterness in a caffeine-MSG mixture. Since earlier experiments did not indicate any interaction between oil and bitterness, the decrease in the perceived bitterness of this binary mixture is attributed to an increase in umami which is likely to have suppressed bitterness, the perceptually dominant component in this mixture. These findings suggest a gustatory role for fats in modulating the taste profile of mixtures, in particular, enhancing total taste intensity, prolonging taste duration, and enhancing umami. A taste receptor-based model of fat perception provides for an orosensory mechanism capable of signalling the arrival of the most energy-dense nutrient, essential fatty acids and fat-soluble vitamins. The chemosensory signal may also be the basis for hedonic responses with subsequent implications for intake.

Les propriétés de cristallisation et les interactions moléculaires intervenant dans des matières grasses naturelles, en létat ou modifiées, ainsi que dans leurs mélanges ont été caractérisées, et ceci dans le contexte de la mise sur le marché de produits alimentaires gras à teneur réduite en acides gras trans. En plus dune compréhension des propriétés de cristallisation, ce travail propose une modélisation offrant une possibilité de prédiction de propriétés de systèmes ternaires à partir des systèmes binaires correspondants. Enfin, la dernière partie de ce travail concerne une étude plus détaillée de la cinétique du polymorphisme et de lintersolubilité des constituants triglycéridiques dun composé majeur des formulations « low-trans » : lhuile de palme, ainsi que dun grand nombre de ses fractions (stéarines, oléines, superoléines et fractions intermédiaires). Lensemble des résultats démontre lintérêt de réaliser des diagrammes de phases pour létude du comportement dynamique de systèmes lipidiques et la nécessité de combiner plusieurs techniques pour caractériser ces systèmes hautement complexes et instables.

In the last few years, especially in the developed countries, an increment in demand for fresh-cut fruit by the consumers of all ages has occurred. This increase is mainly due to the importance that people are giving to the consumption of fresh, healthy, and low-calorie food products. Fresh-cut pineapple (Ananas comosus) is one of the fruits that consumers can eat quickly and still enjoy its benefits; however, its shelf-life is very short (7 days). A means to preserve all the natural and beneficial components of fresh-cut pineapple is coating the fruit with an edible material, a coating. This coating acts as a barrier against moisture loss and gas exchanges and can be a carrier of other components like antimicrobials, which can help to extend the shelf-life of the fresh-cut fruit. The main objective of this study was to develop an edible coating with an antimicrobial agent for fresh-cut pineapple and to determine its effectiveness in extending shelf-life and preserving fruit quality attributes. Different treatments consisted of several concentrations of sodium alginate (0.5%, 1%, and 2%); beta-cyclodextrin, trans-cinnamaldehyde (antimicrobial), pectin, and calcium chloride were tested for formulation of the edible coating. The layer-by-layer technique with a dipping method was used to coat the fruits. Pineapples were properly cleaned with a chlorine solution (300 ppm) and triangular prisms (3.6 cm per side) were cut using a triangular cutter. The length of the triangular prisms was adjusted to 2.54 cm using a small knife measured with a ruler. Color, texture, pH, degrees Brix (total soluble solids), acidity, vitamin C, moisture content, and weight loss, were monitored every 3 to 4 days for 15 days. Microbiological tests (aerobic plate counts, psychrotrophic counts, and yeast and molds counts) were performed to determine the effectiveness of the antimicrobial compound. In terms of microbiological and physicochemical quality attributes, the coating improved the shelf-life of the fresh-cut pineapple up to 12 days compared to the control (fresh-cut pineapple without the coating) which only lasted 7 days at 4 degrees C. Color, texture and pH, were better preserved in the treated (coated) fruit compared to controls (uncoated). Different concentrations of the solutions in the formation of the coating had different results in terms of the preservation of the quality attributes of the fruit. Antimicrobial coatings with a concentration of alginate of 1% and 2% (w/w), pectin 2% (w/w) and calcium chloride 2% (w/w) presented a satisfactory formulation to preserve fruit quality attributes like moisture content, help to control juice leakage, and avoid microbial growth. Antimicrobial coating with 1% of alginate (w/w), 2% of pectin (w/w), 2% of calcium chloride (w/w) and 2% of antimicrobial compound (w/w) was the best formulation. This research demonstrates the feasibility of an alginate-based antimicrobial edible coating, which acts as a carrier of antimicrobial compounds for fresh-cut pineapple.

Thèse : Sciences : Université, Faculté des sciences de Paris : 1855. / Titre provenant de l'écran-titre.