Dissertations / Theses on the topic 'Glucose ester'

Glucose, as the most plentiful sugar in nature, is a renewable resource and possesses excellent record in health safety. Levulinic acid is a platform chemical which plays an important role  in  biomass transformation and reactive intermediates. Both glucose and levulinic acid can be produced by biomass conversion with green processing techno logies. Due to the rising needs for bio-based, eco-friendly and non-toxic plasticizers, glucose levulinates as bio­ plasticizers were synthesized from glucose and levulinic acid, by utilizing microwave radiation or conventional condensation reaction (direct-heating method ). Acid number for the reaction liquor was measured by acid-base titration to follow the decrease of acid groups due to the reaction and the trend in  the acid number within reaction time displayed the process of esterification and possible sensitivity of the reaction rate to reaction scale. It showed that microwave radiation had superior ability in  enhancing reaction speed but it was also more sensitive to reaction scale and generated more diverse prod ucts  than the direct-heating method. Besides, the process of reaction and formation  of ester  bonds was  followed  and confirmed by FT IR. The achieved levulinate products were extracted by 2-pro panol and ethyl acetate. The practices showed several serio us problems in 2-propanol extraction, including high dosage required  for  NaCl and solvent and difficulties in purification. The ethyl acetate proved to be a suitable solvent for this study and the  extrac ted  product s  from  the Con-24hrs  and Micro-3/4/5/6/7hrs  were  characterized  by  1H  NMR,  13C N :tvlR. and LDI-MS. The results from spectrum suggested the presence of GL,. and G J .'l. type of levulinates. That means the glucose levulinates were  successfully  synthesized  although  the  dehydration side reaction of glucose was inevitable leading to the generation of glucosidic bonds. In addition, BG (mixture of glucose and glycosidic levulinates) was evaluated by so lution casting of starch and PVC. In order to minimize the microbial contaminations in solution casting of  starch, a  modified  method  was raised and applied. The results showed that 40% BG had goo d miscibility with starch and the conclusion was further proved by DSC measurements, while the BG performed poor miscibility with  PVC.

En 2030, la chimie du végétal occupera 30% de la chimie totale en France. Les bioressources offrent l’opportunité de substituer les produits issus de la pétrochimie. Avec un taux de pénétration stable de 25-30% selon les prévisions de l’ADEME, les biotensioactifs constituent une voie de valorisation des produits issus de l’agriculture. Les sources lipophiles et hydrophiles nécessaires à l’obtention de ces composés amphiphiles peuvent être totalement naturelles. Ainsi, la graine de chia de la variété Oruro® a été utilisée comme source de la partie hydrophile représentée par le mucilage. Le mucilage surfacique de la graine de cette variété domestiquée en France est constitué de polysaccharides, de protéines et de minéraux. Il peut être extrait de façon efficace par cavitation ultrasonore en milieux aqueux. La composition et les propriétés du mucilage sont liées au temps d’extraction. Ce mucilage constitue une source hydrophile pour l’obtention d’esters amphiphiles. La source lipophile choisie est l’amande de Irvingia gabonensis issue d’une variété riche en beurre laurique haut myristique (51%) et laurique (38%). Les triglycérides de ce beurre sont constitués par des mélanges en acides gras saturés. Ce sont de bons candidats pour l’alimentation, la nutrition et aussi l’industrie et la production de biotensioactifs technofonctionnels. Le travail vise donc la valorisation simultanée du mucilage et de l’huile de I. gabonensis par la synthèse de biotensioactifs. Deux voies de synthèse pour l’obtention des esters amphiphiles ont été explorées. La première voie a impliqué la mise en œuvre de la réaction de transestérification entre le glucose et le laurate de méthyle en milieu eutectique profond DES Chlorure de choline/glucose. La deuxième voie fait appel à la catalyse acide en milieu organisé par la mise en œuvre de la réaction d’estérification du glucose ou du mucilage avec les acides gras laurique C12:0, et myristique C14:0 en présence de l’acide dodécylbenzène sulfonique (ADBS). Les études des réactions d’estérification ont préalablement été réalisées à partir du glucose puis transposées au mucilage. L’utilisation de l’ADBS doté d’un double rôle en tant que catalyseur de Brönsted et tensioactif favorise la mise en contact des réactifs, catalyse la réaction la réaction d’estérification entre les hydroxyles du glucose ou des polysaccharides et les groupes carboxyliques des acides gras laurique C12:0 et myristique C14:0 et par conséquent permet l’obtention des esters de glucose de degré de substitution DS=1-2. Les propriétés tensioactives et émulsionnantes sont comparables de ces esters de glucose sont comparables à celles d’un ester commercial Olivem 1000, un mélange d’olivate de sorbitan et d’olivate de cétéaryl. La réaction entre le mucilage de chia Oruro® et le mélange d’acides gras de I. gabonensis en présence de l’ADBS a permis une modification structurale profonde du biopolymère. Sa lipophilisation est obtenue par la double monoacylation des sites hydroxyles du mucilage par le mélange d’acides gras laurique C12:0 et myristique C14:0. La viscosité intrinsèque du mucilage acylé est très faible (6,34 dL/g) par rapport à celle du mucilage brut (36,18 dL/g) utilisé en tant que réactif de départ. Il en découle un changement profond de propriétés techno-fonctionnelles du mucilage acylé
In 2030, vegetal-based chemistry will occupy 30% of total chemistry in France. Bioresources offer the opportunity to substitute products from petrochemicals. With a stable penetration rate of 25- 30% according to ADEME forecasts, biosurfactants are a way of adding value to agricultural products. The lipophilic and hydrophilic sources needed to obtain these amphiphilic compounds can be completely natural. Thus, the chia seed of the Oruro® variety has been used as a source of the hydrophilic part represented by the mucilage. The surface mucilage of the seed of this variety domesticated in France is made up of polysaccharides, proteins and minerals. It can be extracted effectively by ultrasonic cavitation in aqueous media. The composition and properties of the mucilage are related to the extraction time. This mucilage constitutes a hydrophilic source for obtaining amphiphilic esters. The lipophilic source chosen is the Irvingia gabonensis almond from a variety rich in high myristic (51%) and lauric (38%) butter. The triglycerides of this butter are made up of mixtures of saturated fatty acids. They are good candidates for food, nutrition and also industry and production of technofunctional biosurfactants. The work is therefore aimed at the simultaneous valorization of the mucilage and oil of I. gabonensis by the synthesis of biosurfactants. Two synthesis routes for obtaining amphiphilic esters have been explored. The first pathway involved the implementation of the transesterification reaction between glucose and methyl laurate in a deep eutectic medium DES Choline chloride/glucose. The second pathway involved acid catalysis in an organized medium by the implementation of the esterification reaction of glucose or mucilage with lauric C12:0 and myristic C14:0 fatty acids in the presence of dodecylbenzene sulfonic acid (DBSA). The studies of the esterification reactions were previously carried out using glucose and then transferred to mucilage. The use of DBSA with a dual role as a Brönsted catalyst and surfactant promotes the contact of the reagents, catalyzes the esterification reaction between the hydroxyl groups of glucose or polysaccharides and the carboxylic groups of the C12:0 lauric and C14:0 myristic fatty acids and therefore allows the glucose esters of degree of substitution DS=1-2 to be obtained. The surfaceactive and emulsifying properties of these glucose esters are comparable to those of a commercial Olivem 1000 ester, a mixture of sorbitan olivate and cetearyl olivate. The reaction between chia Oruro® mucilage and the fatty acid mixture of I. gabonensis in the presence of ADBS resulted in a profound structural modification of the biopolymer. Its lipophilization is obtained by the double monoacylation of the hydroxyl sites of the mucilage by the mixture of lauric C12:0 and myristic C14:0 fatty acids. The intrinsic viscosity of the acylated mucilage is very low (6.34 dL/g) compared to that of the crude mucilage (36.18 dL/g) used as starting reagent. This results in a profound change in the techno-functional properties of the acylated mucilage

An increased incidence of illness has been observed in athletic populations undergoing intensive training and competition. T-lymphocytes are central to cell-mediated adaptive immune responses and have been the subject of many studies investigating the relationship between T-lymphocyte function, exercise and athlete health. A decrease in T-lymphocyte function following acute intensive exercise has commonly been described, making them a possible factor contributing to increased susceptibility in athlete populations. However, there is much controversy regarding the interpretation of traditional methodology (mitogen-induced proliferation assays) used to assess Tlymphocyte function during and after exercise. Current lymphocyte proliferation assays do not determine individual T-lymphocyte function or independently establish the function of T-lymphocyte subsets. Therefore, the overall aim of this thesis was to develop and apply new techniques to the study of the effect of acute exercise on the function of T-lymphocytes. Specifically, this thesis aimed to determine the effect of acute intensive exercise on the function of individual T-lymphocytes and T-lymphocyte subsets. The major findings of this thesis are that acute intensive exercise does impair Tlymphocyte responses to mitogen. The cellular expansion of both CD4 and CD8 Tlymphocytes as measured by the application of the new CFSE technique is decreased by acute exercise. The exercise effect observed is not an initial effect on cell function, as exercise does not impair the ability of T-lymphocytes to respond to stimulus (activation) and undergo cell division (mitosis) in response to mitogen. Instead, acute exercise is associated with an increased level of apoptosis in mitogen-stimulated cultures and this results in a reduction of the overall expansion of the cell population in vitro. The mechanism by which exercise induces apoptosis was examined using carbohydrate supplementation and it was found that carbohydrate feeding can prevent exercise-induced apoptosis, and hence attenuates the decrease in T-lymphocyte function. However, the mechanism by which carbohydrate prevents apoptosis does not appear to be via moderation of T-lymphocyte numbers or blood cortisol concentrations, rather it may be due to improved glucose availability.

La methode de michael a ete utilisee pour la synthese de -o glycosides d'aryle afin de pouvoir etudier leurs activites comme inducteurs de genes de virulence. Ainsi ont ete synthetises 22 glycosides de derives phenoliques ayant une structure proche de celle de l'acetosyringone. Ensuite, des cetones , ethyleniques comme des chalcones, des benzalacetones et des dibenzalacetones ont ete preparees et glycosylees. Pour les chalcones dihydroxylees, la methode de michael a permis la glycosylation du cote du noyau phenolique portant un ou deux groupes methoxy. Pour acceder au greffage de l'autre cote, nous avons du realiser d'abord la glycosylation d'une cetone ou d'un aldehyde phenolique puis l'aldolisation de ces glycosides. L'acces direct aux -d-o-glycosides d'aryle a ete recherche par une methode originale sans protection prealable de la partie sucre. Il est possible de preparer des derives 1,2-sulfite cyclique et de le faire reagir ensuite avec un ion phenate pour obtenir le -o-glucoside stereoselectivement. Cette methode one pot ne necessite donc aucun groupe protecteur et nous a permis en particulier d'acceder directement a des -d-o-xylosides. Deja une grande majorite de ces produits ont ete testes au laboratoire d'androgenese et biotechnologie d'amiens et il a pu etre degage quelques caracteristiques structurales necessaires a leur efficacite comme inducteurs de genes de virulence

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The horse has a natural predisposition for the sport, however, its use in competitions can result in stress related problems that impair its sporting performance and especially its health. In this way it is fundamental not only to understand how the different risk and resilience factors to different stressors influence the response to stress, but also to develop strategies that can prevent or minimize the deleterious effects of stress. In this sense, acupuncture is an ancient technique of Traditional Chinese Medicine that has been used in the treatment and prevention of stress-related diseases. The present study proposed the use of two models of stress: one physical (physical exercise) and another psychological (startle model) to verify the reactivity to the stress of athletes horses. In addition, it was also evaluated if horses of different sporting modalities present different psychological stress responses and if acupuncture can alter the responses to physical stress. In the experiment 1, 16 Thoroughbred race horses were submitted to a exercise in the field of high intensity and short duration (12 m / s, 4 min). The RR intervals for analysis of the Heart Rate Variability were acquired through the Polar Equine ? heart rate monitor and blood samples were collected before and immediately after 2h, 4h, 6h, and 24h after exercise. The exercise promoted autonomic alterations in the sympatho-vagal balance since it significantly increased the low frequency component (LF), the heart rate and the LF / HF ratio, and decreased the high frequency component (HF) (p <0.01). There was an increase in hematocrit, plasma proteins, glucose and plasma lactate immediately after exercise (p <0.001). There was an increase (p <0.01) in serum cortisol values after 30 minutes, returning to baseline values after 60 min. However, no significant difference was observed in plasma cytokines IL-1? and IL-6 between moments after exercise and baseline. In experiment 2, horses of the experimental group 1 after exercise were randomly divided into two groups: CTL (C2): Control (without manipulation) and ACUP (C2)): animals submitted to weekly sessions of acupuncture at points VG1, C7, VG20 and B52 for 10 weeks. After the treatment period the animals repeated the same exercise and the same parameters were analyzed. Acupuncture reduced the LF / HF ratio, promoting a faster recovery of the animals, showing no influence on the other parameters analyzed. In the experiment 3, 24 equines were used, from three equestrian modes: Polo (PSI) (n = 9), Dressage (Brazilian Horse Riding) (n = 6) and Endurance (n=6) were subjected to the experimental model of startling through the abrupt opening of an umbrella. The results showed that endurance horses presented a significantly less intense startle-induced autonomic response than Polo and Dressage horses (lower LF / HF ratio at the time of the jump), paradoxically Enduro horses have cortisol levels in response in response to the startle than Polo horses. However, there was no difference between the modalities in the behavioral response after the startle, and Polo horses had significantly higher baseline levels of cortisol than the other modalities and did not change their cortisol levels in response to stress. Thus, we can conclude that 1) the exercise in the field of high intensity and short duration promoted adaptive changes characteristic of stress, being able to be used in studies of reactivity to stress in race horses; 2) acupuncture has a modulating effect on the stress-induced autonomic response in athletic horses, and 3) the equestrian modalities of Dressage, Polo and Endurance present different stress reactivity
O cavalo tem uma predisposi??o natural para o esporte, no entanto, o seu uso em competi??es pode resultar em problemas relacionados ao estresse que prejudicam seu desempenho esportivo e principalmente a sua sa?de. Desta forma ? fundamental n?o apenas entender como os diferentes fatores de risco e de resili?ncia a diferentes estressores influenciam a resposta ao estresse, como tamb?m desenvolver estrat?gias que possam prevenir ou minimizar os efeitos delet?rios do estresse. Neste sentido a acupuntura ? uma t?cnica milenar da Medicina Tradicional Chinesa que tem sido utilizada no tratamento e preven??es de doen?as relacionadas ao estresse. O presente estudo prop?s o uso de dois modelos de estresse: um f?sico (exerc?cio f?sico) e outro psicol?gico (modelo de sobressalto) para verificar a reatividade ao estresse de cavalos atletas. Al?m disso, tamb?m foi avaliado se cavalos de diferentes modalidades esportivas apresentam respostas ao estresse de psicol?gico distintas e se acupuntura pode alterar as respostas ao estresse f?sico. No experimento 1, 16 equinos de corrida da ra?a Puro Sangue Ingl?s foram submetidos ao exerc?cio a campo de alta intensidade e curta dura??o (12 m/s, 4min). Os intervalos RR para an?lise da Variabilidade da Frequencia Card?aca foram adquiridos atrav?s do frequenc?metro card?aco Polar Equine? e as amostras de sangue foram coletadas antes e, imediatamente, 2h, 4h, 6h, e 24h ap?s o exerc?cio. O exerc?cio promoveu altera??es auton?micas no balan?o simpato-vagal uma vez que aumentou significativamente o componente de baixa frequ?ncia (LF), a frequ?ncia card?aca e a raz?o LF/HF e diminuiu o componente de alta frequ?ncia (HF) (p < 0.01). Houve aumento do hemat?crito, das prote?nas plasm?ticas, glicose e lactato plasm?tico imediatamente ap?s o exerc?cio (p < 0.001). Houve aumento (p<0.01) nos valores s?ricos de cortisol ap?s 30 minutos, retornando aos valores basais ap?s 60min. No entanto, n?o foi observado diferen?a significativa nas citocinas plasm?ticas IL-1? e IL-6 entre os momentos ap?s exerc?cio e o momento basal. No experimento 2: os equinos do experimento 1 ap?s o exerc?cio foram aleatoriamente divididos em dois grupos: CTL (C2): Controle (sem manipula??o) e ACUP (C2)ACUP (C2): animais submetidos a sess?es semanais de acupuntura nos pontos VG1, C7, VG20 e B52 durante 10 semanas. Ap?s o per?odo de tratamento os animais repetiram o mesmo exerc?cio e foram analisados os mesmos par?metros. A acupuntura reduziu a raz?o LF/HF, promovendo uma recupera??o mais r?pida dos animais n?o apresentando influ?ncia nos demais par?metros analisados. No experimento 3, foram utilizados 24 equinos, pertencentes a tr?s modalidades equetres: P?lo (ra?a PSI) (n=9), Adestramento (ra?a Brasileiro de Hipismo) (n=6) e Enduro (Puro Sangue ?rabe) (n=9) submetidos ao modelo experimental de sobressalto atrav?s da abertura abrupta de um guarda-chuva. Os resultados mostraram que cavalos de enduro apresentaram resposta auton?mica induzida pelo sobressalto significativamente menos intensa que cavalos de Polo e Adestramento (menor raz?o LF/HF no momento do sobressalto), paradoxalmente cavalos de Enduro possuem n?veis de cortisol em resposta ao sobressalto mais altos que cavalos de Polo. N?o houve diferen?a entre as modalidades na resposta comportamental ap?s o sobressalto, no entanto cavalos de P?lo apresentam n?veis basais de cortisol significativamente mais altos que as demais modalidades e n?o variaram seus n?veis de cortisol em resposta ao estresse. Dessa forma, podemos concluir que 1) o exerc?cio a campo de alta intensidade e curta dura??o promoveu altera??es adaptativas caracter?stica de estresse, podendo ser utilizado em estudos de reatividade ao estresse em cavalos de corrida; 2) a acupuntura tem um efeito modulador da resposta auton?mica induzida pelo estresse em cavalos atletas e 3) as modalidades equestres de Adestramento, Polo e enduro apresentam reatividade ao estresse distintas

This thesis describes the synthesis, hydrolysis and analysis of menthiafolic acid, a precursor to wine lactone in wine. (R)-Menthiafolic acid was synthesised and then taken through acid hydrolyses to confirm its conversion to wine lactone under wine-like conditions and to determine the chirality of the resultant product. A Gas Chromatography/ Mass Spectrometry (GC/MS) Stable Isotope Dilution Assay (SIDA) method was developed to analyse for this compound in grapes and wine. Chiral analysis was also carried out on wine extracts to confirm which enantiomers of menthiafolic acid and wine lactone are present in real wine samples. Bioconversion of the glucose ester of menthiafolic acid utilising three different microorganisms was evaluated in order to determine if menthiafolic acid is produced and hence if this compound is an indirect precursor to wine lactone through initial degradation to menthiafolic acid. Chapter 1 comprises an introduction and literature review. Chapter 2 concerns the synthesis and acid hydrolysis of (R)-menthiafolic acid. The synthesis gave a mixture of 95% (R)-enantiomer and 5% (S)-enantiomer menthiafolic acid. Hydrolysis was carried out under mild, wine-like conditions and under harsh Simultaneous Distillation Extraction (SDE) conditions. These hydrolyses showed that this compound is, in fact, converted to wine lactone under wine-like conditions but both the ‘natural’ (-)-isomer of wine lactone and its enantiomer are produced in varying proportions depending on the hydrolytic conditions. This work has been published; Giaccio et al. Journal of Agricultural and Food Chemistry 2011, 59, 660. Chapter 3 describes the development of a SIDA method for the analysis of menthiafolic acid in grapes and wine. Extraction methods were investigated for model wine solutions and then transferred to white wine. A d₅-analogue of menthiafolic acid was prepared for use in later quantifications. Grapes and wines were analysed and menthiafolic acid was found in the wines in varying concentrations ranging from < 10 µg/L to 342 µg/L with the highest concentration found in a Lexia wine. Wines analysed showed menthiafolic acid in significant concentrations which could potentially produce wine lactone in concentrations above its aroma threshold. Grape analyses were also carried out and menthiafolic acid was observed in concentrations ranging from 16 µg/L to 235 µg/L. Gerwütztraminer grapes contained the greatest concentration of this precursor. Chiral analysis of menthiafolic acid present was also carried out on grape and wine samples. The analyses showed that the (S)-enantiomer of menthiafolic acid is the more prevalent enantiomer in these particular grape and wine samples. Chapter 4 concerns fermentation studies of the glucose ester of menthiafolic acid. The SIDA method discussed in Chapter 3 was used to analyse for menthiafolic acid in these samples in order to determine if menthiafolic acid is released from the glucose ester via fermentation with various yeast and bacteria. Approximately 15% bioconversion of the glucose ester to menthiafolic acid was observed when fermenting with Saccahormyces cerevisiae (strain AWRI 838). Bioconversion occurred to a lesser extent (approx. 5%) when fermenting with the lactic acid bacteria Oenococcus oeni (strain VP-41) and even less of the glucose ester was converted to menthiafolic acid when fermenting with spoilage yeast Dekkera bruxellensis (strain AWRI 1499). Menthiafolic acid was not observed in a concentration above the limit of quantification in D.bruxellensis fermentations. Chapter 5 details an attempt to develop a quantification method for wine lactone in model wine. Extraction of wine lactone from a white wine was also attempted. Chiral analysis of wine lactone extracted from wine by continuous liquid extraction was also conducted showing that the predominant enantiomer of wine lactone present in the wine analysed was, in fact, the (+)-enantiomer which has not previously been reported in wine. The (-)-enantiomer of wine lactone was also observed and the ratios of the two wine lactone enantiomers correlated with what was expected when taking into account the ratios of menthiafolic acid also present in the wine. Chapter 6 comprises the experimental methods, materials and instrumentation utilised in these studies.
Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine, 2013

The extracellular matrix (ECM) governs many cellular processes through biochemical and mechanical cues. Particularly, the effect ECM mechanical properties on cells fate has been well established over the years. Many hydrogel systems have been used to mimic the dynamic stiffening processes occurring in ECM. However, changes in ECM stiffness does not fully recapitulate the mechanics of native ECM, as viscoelasticity is also a major factor contributing to ECM dynamic property. This thesis describes the design and characterization of an enzyme-crosslinked hydrogel system that is not only capable of being stiffened on demand, but also can be tuned to obtain viscoelasticity. The first objective of this thesis was to utilize horseradish peroxidase (HRP) to crosslink thiol-norbornene hydrogel and use mushroom tyrosinase (MT) to create secondary DOPA-dimer crosslinks that stiffened the hydrogel. The cytocompatibility of HRP-mediated thiol-norbornene gelation and the effect of stiffening on cell fate was evaluated. The second objective of this thesis represented the first step towards developing a hydrogel system whose viscoelasticity could be dynamically tuned. Thiol-norbornene hydrogel was designed to yield dynamically adaptable boronic ester bonds via partial enzymatic reaction. Thiol-norborne hydrogel was made to contain hydroxyl phenol as well as boronic acid residues within its network. MT, in this case was used to oxidize the hydroxy phenol moieties into DOPA, which then complexed with boronic acid, created dynamic bonds, introducing viscoelasticity to an initial elastic hydrogel.

Phenylpropanoid glycosides are naturally occurring compounds, most commonly appearing in fruits and vegetables that possess biological activities such as antiviral, antimicrobial, antioxidant, antifungal and many others. They are composed of a sugar that is linked (with a glycoside linkage) to a hydroxycinnamoyl residue and/or another group. These types of compounds have been used in Asian traditional medicine for many years but only recently they began to be studied and synthetized for further uses. The reason behind this is the low percentage of these esters in the natural sources and the relatively high complexity of the carbohydrate molecules. In this project we aimed to develop and optimize protocols for the synthesis of phenylpropanoid esters of glucose and methylglucopyranose substituted with a cinnamic acid moiety. In order to achieve that three different esterification techniques were tested; the Steglich esterification, the Mitsunobu esterification and transesterification through enzymatic catalysis. The first two being well known and established procedures and the last being a “greener” alternative that has an enormous potential in carbohydrate synthesis.

碩士
大葉大學
食品工程研究所
89
Sugar ester used in pharmaceutical, detergent, cosmetic, food industries. At present, sugar esters for chemical synthesis are commercially available. However, the process require high temperature and long time for chemical synthesis. It may cause lipids deterioration and unwanted products. Lipase synthesis sugar esters under mild reaction. In this study, 0.1 M methyl glucoside esterification in organic solvent with lauric acid. Effect of different reaction time ( 6-24 h ), temperature ( 30-50 ºC ), and methyl glucose to lauric acid molar ratio ( 1:2-1:6 ) on the acid incorporation ratio of methyl glucose ester, catalyzed by lipase AY, G, PS and IM77. Lipase catalyzed in organic system, but organic solvents and fatty acid attack to lipase which effected to inactive. If used immobilized lipase would not be effected. Acid incorporation of methyl glucoside esters effected to substrates molar ratio in this study. Immobilized lipase IM77 more activity and stable than the other lipase. Response surface methodology ( RSM ) and 5-level- 4-factor central composite rotatable design, CCRD were used to evaluate the effect of synthesis parameters, reaction time ( 4-20 h ), temperature ( 25-65 ºC ), methyl glucose to lauric acid molar ratio ( 1：2-1：6 ), and enzyme amount ( 10-50% ). Based on the ridge max analysis, optimum condition were：reaction time 8 h, temperature 44.5 ºC, substrate molar ratio 1：3.1, enzyme amount 15%, and acid incorporation ratio 2.48 ± 0.56 by lipase IM77.

The work described in this dissertation focused on chemistry related to the use of aqueous sodium hydroxide as a treatment in the processing of wheat straw. A major emphasis was the comprehensive evaluation of straw component partitioning due to sodium hydroxide (NaOH) processing. This was evaluated over a range of NaOH concentrations (0­‐10%, w/v), all at 50°C, 5 h treatment period, and 3% solid loading. Solid and liquid phases resulting from NaOH treatments were evaluated. Total solids recovered in the NaOH­‐treated solid phase ranged from 47.4­‐88.0%. Overall carbohydrate recovery in the combined solid and liquid phases was negatively correlated with the alkali concentration of the treatment liquor. The glucan content of the NaOH‐treated solid phase ranged from 37.2­‐67.4%. Glucan recovery in the solid phase was relatively high in all cases, the minimum value being ~98%. Increasing amounts of xylan partitioned into the liquid phase as sodium hydroxide concentrations increased – it ranged from 31­‐83% of the xylan being recovered in the soluble phase. Carbohydrate analyses of the pretreated liquor revealed that the majority of carbohydrate loss from the solid fraction could be recovered in the liquid phase in form of oligomers and monomers due to alkaline degradation. The interconversion of glucose, fructose, and mannose under the alkaline condition played an important role in the presence of those sugars. Increase in NaOH concentration contributed to increase in amount of cellulose­‐derived and hemicellulose‐derived oligomers in the pretreated liquor. All oligomers except fructooligomers in NaOH pretreated liquor were higher than those found in water extraction at 50°C, 5 h. Total carbohydrate recovery from the solid and liquid fractions was as high as 99% for glucose and glucan in 5% NaOH treatment and 80‐95% for xylose and xylan in 1-­10% NaOH treatment. The presence of NaOH as extraction reagent dramatically induced lignin and ash removal from the pretreated solid with up to 63% acid insoluble lignin (AIL) and 87% ash extraction. Solid fractions resulting from NaOH pretreatments (up to 5% NaOH) were tested for their susceptibility to enzymatic saccharification using cellulase and cellulase/xylanase enzyme preparations. The cellulase/xylanase enzyme preparation was found to be more effective at cellulose saccharification than the cellulase enzyme preparation alone. Maximum glucose yield, which corresponded to the 5% NaOH treatment, was 82% over the standard 48 h saccharification period. Extended saccharifications times to 120 h showed that the conversion yield approached 90%. Sequential treatments of the straw (i.e. initial alkali treatment – first enzyme saccharification – second alkali treatment ‐ second enzyme treatment) revealed the NaOH treatment has the potential to render essentially all (~99%) of the straw glucan susceptible to enzyme saccharification. This suggests that the layered molecular arrangement of cellulose, hemicellulose, and lignin in the cell wall impacts biomass recalcitrance and glucan conversion yield. The other major focus of this dissertation research was the characterization of alkali neutralization, which occurs during the aqueous alkali processing of wheat straw. The approach taken was to evaluate the time course of alkali uptake and to determine the underlying nature of alkali uptake. The knowledge generated from this study is useful for understanding the nature of the alkali‐induced chemistry that is at the heart of alkali processing of agricultural byproducts, foods, and forest products. Alkali uptake/acid generation measurements were monitored for wheat straw suspensions at pH 11 and 30°C. The first phase of alkali uptake corresponded to the 30‐second time period over which the pH of the wheat straw suspension was adjusted from its original pH (~6.6) to pH 11. Alkali neutralization during this period was attributed to the instantaneous ionization of solvent accessible Bronstad acids. Following pH adjustment to 11.0, the time course of subsequent alkali uptake was recorded. The time course appeared biphasic. The early phase, which corresponded to the relatively rapid uptake of alkali, was evident during the first 24 hours. The later phase, which was characterized by the relatively slow uptake of alkali, was maintained for the length of the study (up to 96 hours). Alkali uptake during the early phase of the time course appears to be determined by the rate of hydrolysis of readily accessible esters – primarily acetic acid esters (acetyl groups). Alkali uptake during the later phase of the time course appears to be impacted by the rate of alkali penetration into the straw and the rate of production of alkali‐induced acid degradation products. The uptake of alkali in the pH adjustment phase was ~ 120 μEq per gram wheat straw, the uptake of alkali in the early phase of time course was ~ 1,064 μEq per gram wheat straw, and the rate of uptake in the later phase of the time course 6.10 μEq per gram wheat straw per hour. Amount of acetyl groups, ferulic acid, and p-­coumaric acid generated during 96-­h pretreatment revealed that they are major esters being hydrolyzed under the studied condition. Combined, these ester-­derived acids contributed up to ~ 28% of overall alkali uptake. In addition, alkaline degradation products quantified in this study showed additional ~ 28% contribution to the overall alkali uptake.
Graduation date: 2012

Six long chain fatty acid esters of quercetin-3-O-glucoside (Q3G) acylated enzymatically were used for determining their antiproliferative action in comparison to precursor compounds (quercetin, Q3G and six fatty acids namely, stearic acid, oleic acid, linoleic acid, alpha-linolenic acid, eicosapentaenoic and docosahexanoic acids) using HepG2 cells. Long chain fatty acid esters of Q3G showed significant inhibition of cell proliferation (approximately 85% to 90%) compared to the precursor compounds and two prescribed anticancer-drugs (Sorafenib and Cisplatin) after 6 hrs and 24 hrs by inducing cell cycle arrest, apoptosis and DNA topoisomerase II inhibition. Among the six fatty acid esters of Q3G, oleic acid ester (OA-Q3G) displayed the greatest anti-proliferation action and upon further investigation showed significant regulation of expression of genes involved in cell cycle, growth, survival and apoptosis at gene and protein level. Overall, results of the study suggest strong potential of these novel compounds in treatment of liver cancer.

Tumor-induced immunosuppression can occur by multiple mechanisms, each posing a significant obstacle to immunotherapy. Evidence presented in this dissertation suggests that aberrant cytokine signaling, as a result of altered metabolism of Chronic Lymphocytic Leukemia (CLL) cells, confers a selective advantage for tumor survival and growth. Cells from CLL patients with aggressive disease (as indicated by high-risk cytogenetics) were found to exhibit prolongation in Interferon (IFN)-induced STAT3 phosphorylation, and increased levels of reactive oxygen species (ROS) in these cells reflected these signaling processes. Changes in the relative balance of phospho-STAT3 and phospho-STAT1 levels, in response to combinations of IL-2 + Toll-like receptor (TLR)-7 agonist + phorbol esters, as well as IFN, were associated with the immunosuppressive and immunogenic states of CLL cells. In addition, immunosuppressive leukemic cells were found to express high levels of proteins with O-linked N-acetylglucosamine (O-GlcNAc) modifications, due to increased metabolic activity through the Hexosamine Biosynthetic Pathway (HBP), which caused impaired intracellular signaling responses and affected disease progression. A conclusion of the studies presented here is that the intrinsic immunosuppressive properties of leukemic cells may be overcome by agents such as Resveratrol that target metabolic pathways of these cells.