Ph.D. (Chemistry) / Please refer to full text to view abstract

The aim of this thesis was the development of the method for the determination of eight monosaccharides commonly found in glycoproteins by capillary electrophoresis. Namely, it was determination of glucose, galactose mannose, N-acetylglucosamine, N-acetylgalactosamine, fucose, N-acetylneuraminic acid and xylose. Total length of silica capillary with inner diameter of 10 m was 50.0 cm and effective length was 35.0 cm. Background electrolyte was compound of sodium hydroxide of 50 mmol/l concentration, disodium phosphate of 22.5 mmol/l concentration and cetyltrimethylamoniumbromide of 0.2 mmol/l concentration. Samples were injected hydrodynamically with pressure of 5 kPa for 70 s, driving voltage was -30 kV and the pressure of 270 kPa was applied to the outlet vial during the separation; capacitively coupled contactless conductivity detector was used to detect the analytes. The limits of detection were between 5 and 7 mg/l and the limits of quantification were between 16 and 22 mg/l. Repeatability of peak areas and migration times related to 4-(2-hydroxyethyl)-1-piperazinethanesulfonic acid as an internal standard showed values of relative standard deviation lower than 4 %. Conditions for hydrolysis of oligosaccharides to monosaccharides were determined as 4M hydrochloric acid and 100 řC, hydrolysis...

This study evaluated the possible uses for a custom-made Capillary Electrophoresis Contactless Conductivity Detector (CE-CCD). One of the key objectives was to determine whether measurements of conductivity with the device could replace UV-spectroscopy to analyze a range of samples, in particular PVA-MB and monosaccharides. Furthermore, to determine the feasibility of using the specific device as a substitute for UV-spectroscopy analysis, two commercial reference devices were used: one contact based conductivity detector and one potentiostat. Changes in resistance and voltage drops of samples containing the analytes were used to determine whether the analysis with the custom made CE-CCD could replace analysis with UV-spectroscopy. The signal from the PVA-MB compared to variation in the signal of the background electrolyte was discovered to be too great for CE-CCD to be applied as a substitute for UV-spectroscopy.  However both monosaccharides analyzed in the study, glucose and galactose could be detected. Glucose could accurately be detected down to 50 μM and galactose down to 25 μM. A semi-empirical calculation estimated a lower limit of 5 μM for glucose and roughly 8 μM for galactose. PVA-MB could not be detected with the custom made CE-CCD while the monosaccharides can be detected in a range low enough to allow the detector to replace UV-spectroscopy for analysis. The best measurements taken with the detector were not as low as the best data found for UV-spectroscopy, but similar electrochemical applications were found to have reached similar or better values. Further development of the detector may lower its limit of detection to approach and possibly exceed the better measurements taken with UV-spectroscopy.

京都大学 / 0048 / 新制・論文博士 / 博士(農学) / 乙第13074号 / 論農博第2844号 / 新制||農||1046(附属図書館) / 学位論文||H29||N5030(農学部図書室) / 33225 / (主査)教授 安達 修二, 教授 谷 史人, 教授 橋本 渉 / 学位規則第4条第2項該当 / Doctor of Agricultural Science / Kyoto University / DFAM

Fast analysis of different species of molecules in soils is investigated by capillary electrophoresis (CE). Several CE techniques for the analysis of inorganic ions and carbohydrates have been tested. With regard to the intents of pedologists and the usually large number of soil analyses a bundle of CE systems is proposed, capable of effecting time-saving soil analyses. Adapted electrolyte systems recently published and new separation systems are described. Examples of the application of these methods to two different soil samples are presented.

Includes bibliography / xiii, 126 leaves : ill ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, 1989

Thesis (Ph. D.)--University of Missouri--Rolla, 2007. / Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed April 23, 2008) Includes bibliographical references.

Presented diploma thesis was focused on study of biologically active compounds, especially some sugars in cereal products. In experimental part the total of 29 different cereal materials, food industry waste products and natural complex matrixes (microbial polysaccharide, honey, beer) were used. As a part of this work optimization of analytical methods suitable for analysis of simple sugars, oligo- and polysaccharides was done. In cereal samples reduced and neutral sugars were analyzed spectrophotometrically and individual sugars were detected by chromatography. For HPLC/RI analysis optimal mobile phase composition and chromatography conditions were proposed. For mono- a oligosaccharides C18-NH2 sorbent, mixture acetonitril:water 75:25 as mobile phase and flow 1 ml/min were verified as suitable separation parameters. Thin layer chromatography of mono- and oligosaccharides was optimized too. Introduced chromatography and spectrophotometry methods were then applied to analysis of cereal samples. As a model sugar natural microbial polysaccharide pullulan was used to analytical method testing. In cereal products and food matrixes total neutral and reduced sugars as well as products of their acid and enzyme hydrolysis were measured. Detailed analysis of some glycoside composition was tested too. As the most usable method for both qualitative and quantitative analysis of cereal sugars HPLC/RI method was found. To detailed identification of malto-oligosacharides tandem LC/MS/MS technique using derivatization by 1-phenyl-3-methyl-5-pyrazolon was tested too.

Au cours des interactions plante/agent pathogène, la disponibilité en sucres est un des enjeux majeurs pour les deux partenaires. Il s'établit donc une compétition vis-à-vis des ressources carbonées entre l'agent pathogène hétérotrophe pour le carbone et la plante consommant de l'énergie pour se défendre. Les transporteurs de sucres sont les acteurs moléculaires qui interviennent dans cette compétition et probablement dans le devenir de l'interaction. L'objectif de cette étude est de déterminer l'implication des transporteurs de sucres au cours de l'interaction entre la plante modèle Arabidopsis thaliana et le champignon nécrotrophe Botrytis cinerea.Parmi la famille des transporteurs d'hexoses (STPs) d'A. thaliana, l'expression du gène STP13 est régulée positivement durant l'infection par B. cinerea. Le rôle potentiel de STP13 au cours de cette interaction a donc été étudié à l'aide de plantes transgéniques (Knock-Out et surexpresseur). Le suivi du développement des symptômes et la mesure d'absorption du glucose ont permis de montrer des modifications phénotypiques entre les différents génotypes étudiés. Les résultats indiquent une corrélation entre le niveau d'expression de STP13, le transport de glucose et le développement du champignon, confortant ainsi le rôle de STP13 dans la tolérance face à B. cinerea.Les résultats préliminaires de l'étude du transport de glucose à l'échelle cellulaire montrent une inhibition dans des conditions mimant l'infection. Ces analyses ont été effectuées grâce à un modèle constitué d'une suspension cellulaire d'A. thaliana subissant un traitement éliciteur à partir d'un extrait protéique de B. cinerea.Nous nous sommes également intéressés au transport de saccharose à l'échelle de la plante infectée. Nos résultats suggèrent que l'inoculation par le champignon modifie les flux de saccharose classiquement observés créant ainsi une nouvelle force d'appel. Ainsi, la feuille infectée se comporte comme un nouveau puits. Ces travaux de recherche s'inscrivent dans la nécessité d'une meilleure compréhension des mécanismes de transport des sucres qui permettra à terme d'agir sur les capacités de résistance des plantes vis-à-vis d'agents pathogènes. / During plant/pathogen interactions, sugar availability is one of the major issues for both partners. There is a competition for the same carbohydrates necessary for carbon supply on the pathogen's side and to support the additional energy demand for plant's defense. Sugar transporters are the molecular actors in this competition which is determinant for the final outcome of the interaction. In this study, we characterized the implication of sugar transporters in the interaction between the model plant Arabidopsis thaliana and the necrotrophic fungus Botrytis cinerea.Among the A. thaliana hexose transporter family (STPs), STP13 is induced during B. cinerea infection. A potential role of STP13 in this interaction was investigated using transgenic plants (Knock-Out and over-expressor lines). Disease symptoms characterization and glucose uptake assays showed phenotypical variations between the different genotypes. It seems that STP13 expression, glucose uptake and fungus spreading are correlated pointing to a role of STP13 in tolerance to B. cinerea. Other preliminary results showed an inhibition of the cellular glucose uptake upon condition mimicking B. cinerea infection. These analyses were performed on a model composed of an A. thaliana cell suspension elicited with a proteinaceous extract from B. cinerea.We also studied sucrose fluxes in the whole infected plant. Our results suggest that fungus inoculation modifies the usual fluxes creating a new sink.This study may lead to a better understanding of sugar transport mechanisms to improve plant resistance capacity against pathogens in the future.

Introduction/Background: Fructose is a monosaccharide that can also be extracted from sugar beet and sugar cane. There are several foods with high fructose content and affect people’s healthy lifestyle. Dental caries is defined as a dental disease caused by bacteria and the presence of fermentable sugars. Diabetes mellitus type 2 previously known as adult-onset diabetes and referred to as non-insulin-dependent diabetes mellitus.  It is the most common type of diabetes, accounting for approximately 90-95% of all diabetes cases. Aim: The aim of this study was to investigate fructose's influence and its effect on dental caries and in diabetes mellitus type 2 by answering questions: Does fructose have influence and effect on dental caries? Does fructose have an influence and effect on the plasma glucose in diabetes type 2? Method: The study was a literature review of articles from PubMed, CINAHL and Scopus. The selection process followed three steps and underwent quality reviews. There were 18 articles that were included in the study. Results: The result shows that fructose has some impacts and effects on caries and on plasma glucose. Fructose contributes to the growth of Streptococcus mutans. High intake of fructose increases the risk for diabetes mellitus type 2 and the development of dental caries.  Conclusion: When fructose is consumed in large quantities, the caries-causing microorganisms produce acid to such an extent that demineralization of tooth substance can occur. High intake of fructose can also raise the level of plasma glucose and induce fatty liver in diabetes mellitus type 2.