Dissertations / Theses on the topic 'Water soluble carbohydrate'

The macrotricyclic system as a receptor for carbohydrates in organic as well as aqueous media has been extensively studied within the Davis group. The hydrogen bonding and CH-π interactions are the two main non covalent interactions operating for the recognition of carbohydrates in our system. In principle higher affinities could be achieved by enhancing either of these types of interactions. The possibility of enhancing H-bonding interactions with host-guest was explored by the introduction of heterocyclic linkers in the 'temple' receptors. Macrocycle with pyrrole linker 132 and pyridine linker 131 (Figure i) were synthesised and studied for their affinities with different carbohydrate substrates. Pyrrole macrotricycle 132 bound D- Glucose selectively over other substrates with K; = 18 M-1. However pyridine macrotricycle 131 did not show selectivity and higher affinities with any substrates. Figure i. Macrotricycle with pyridine linker 131 and pyrrole linker 132. In collaboration with Roelens group in Firenze, Italy, a series of water soluble C3-symmetric receptors were synthesized and studied for their affinity for carbohydrates. Unfortunately, these series of receptors did not bind the substrates strong enough to be detected by lH NMR titration studies.

Under terminal water deficit, the impact of stem carbohydrate remobilization has greater significance because post-anthesis assimilation is limited, and grain growth depends on translocation of carbohydrate reserves. The working hypothesis of this thesis is that increases in stem carbohydrates facilitate tolerance to terminal drought in wheat. The goals of this thesis are to examine this hypothesis using physiological and genetic tools; identify genes that are related to QTL for stem carbohydrate; work with wheat and barley breeders to integrate findings into the breeding program of the Department of Agricultural and Food Western Australia. The physiological data of three drought experiments (two years in a glasshouse and one year in the field) suggested the maximum level of stem water soluble carbohydrate (WSC) is not consistently related to grain weight, especially, under water deficit. The patterns of WSC accumulation after anthesis differed depending on variety and suggested that WSC degradation and translocation have different genetic determinants. Most of the carbohydrates in stem WSC in wheat are fructans. Because 1-FEH gene was an important gene in fructan degradation, the three copies of this gene (1-FEH w1, 1-FEH w2 and 1-FEH w3) were isolated from the respective genomes of bread wheat. In addition, the genes were mapped to chromosome locations and coincided with QTL for grain weight. The results of gene expression studies show that 1-FEH w3 had significantly higher levels in the stem and sheath which negatively corresponded to the level of stem WSC in two wheat varieties in both water-deficit and well-watered treatments. Strikingly, the 1-FEH w3 appeared to be activated by water deficit in Westonia but not in Kauz. The results suggest that stem WSC level is not, on its own, a reliable criterion to identify potential grain yield in wheat exposed to water deficit during grain filling. The expression of 1-FEH w3 may provide a better indicator when linked to instantaneous water use efficiency, osmotic potential and green leaf retention, and this requires validation in field grown plants. In view of the location of the contribution to grain filling of stem WSC, this is a potential candidate gene contributing to grain filling. The numerous differences of intron sequences of 1-FEH genes would provide more opportunities to find markers associated with the QTL. A new FEH gene was partially isolated from Chinese Spring and the sequence was closely related to 1-FEH genes. This gene, FEH w4, was mapped to 6AS using Chinese Spring deletion bin lines. The polymorphism of this gene was found between different bread varieties using PCRs and RFLPs, and this allowed the gene to be mapped to two populations of Hanxuan 10 × Lumai 14 and Cranbrook × Halberd. In the population of Hanxuan 10 × Lumai 14, it was close to SSR marker xgwm334 and wmc297 where the QTL of thousand grain weight and grain filling efficiency were located. This result indicated this gene might be another possible candidate gene for grain weight and grain filling in wheat.

Le gel est un des facteurs majeurs limitant l'aire de répartition des végétaux. Il a pour conséquence de limiter l'efficience de la circulation de sève brute par formation d'embolie dans les vaisseaux du xylème. Lorsqu'il y a formation de glace dans les tissus, les cellules vivantes peuvent également être lysées dans les organes lignifiés, et dans les bourgeons. Pour pallier cela, différents mécanismes de résistance sont développés pour limiter la formation d'embolie ou la résorber, pour augmenter transitoirement la tolérance à la formation de glace dans les tissus et pour éviter d'exposer les bourgeons et jeunes feuilles aux gels printaniers tardifs. Ces différents traits ont été caractérisés pour onze espèces communes ayant des limites altitudinales potentielles contrastées. Puis la physiologie de l'acclimatation au gel chez Juglans regia L. a été caractérisée, essentiellement à travers les relations entre humidité pondérale, contenu en sucres solubles, climat et levée de dormance. L'ensemble de ces données a permis d'élaborer un modèle prédictif de la résistance au gel en relation avec la physiologie de l'arbre qui pourrait, couplé avec d'autres modèles simulant la période estivale, permettre d'estimer la conjonction de différents stress sur le potentiel de résistance.

Four studies were conducted using high water soluble carbohydrate (WSC), sweet (SM) and low WSC, regular (RM) pearl millet and high WSC (SS) and low WSC (RS) sorghum cultivars. The first and the second studies evaluated the chemical composition and ensiling characteristics of those cultivars. Millet cultivar had no effect on pH. SM silage contained less neutral and acid detergent fiber than RM silage. SS cultivar had less pH than RS cultivar at any ensiling period. RS silage contained greater acid detergent lignin and less non protein nitrogen than SS silage. The third and the fourth studies investigated the feeding value of SM and SS silages. Cows fed SM silage produced milk with greater fat concentration, energy corrected milk, 4% fat corrected milk, and solid corrected milk yield than cows fed corn silage. Milk fat was greater, while milk yield and lactose concentration were less for cows fed SS silage than cows fed alfalfa silage. In conclusion, there is a good potential for pearl millet silage as a source of forage for dairy cows. Further investigations are required to optimize the feeding value of sorghum silage.
Quatre études ont été conduites utilisant deux variétés de millet perlé [i.e. riches en glucides solubles (GS) (MS) et pauvre en GS (MR)] ainsi que deux variétés de sorgho [i.e. riches en GS (SS) et pauvre en GS (SR)]. Les première et deuxième études évaluèrent la composition chimique et les caractéristiques d'ensilage des différentes variétés. La variété de millet n'eut pas d'effet sur le pH. L'ensilage de MS contenait moins de fibre NDF et ADF que l'ensilage de MR. La variété de SS avait un pH inférieur au SR à tout moment lors de la période d'ensilage. L'ensilage de SR contenait une quantité supérieure de lignine et moins d'azote non protéique que l'ensilage de SS. Les troisième et quatrième études investiguèrent la valeur nutritive des ensilages de MS et SS. Les vaches soignées à l'ensilage de MS ont produit du lait plus concentré en gras, énergie du lait corrigée, 4% gras du lait corrigé et rendement en solides du lait corrigé que les vaches soignées à l'ensilage de maïs. La concentration en gras du lait était la même tandis que le rendement en lait et la concentration en lactose furent inférieurs pour les vaches soignées à l'ensilage de SS comparativement à celle soignées à l'ensilage de luzerne. En conclusion, il y a un grand potentiel pour l'ensilage de millet perlé en tant que source de fourrage pour les vaches laitières. D'autres études seraient nécessaires pour optimiser les valeurs nutritives de l'ensilage de sorgho.

Abstract Natural seasonal variation and the effects of cold treatment and nitrogen fertilization on protein expression with special emphasis on dehydrin proteins, were studied using different aged Scots pine (Pinus sylvestris L.). Several different dehydrins were found and their expression depended on the tissue type, tree age or specific treatment. Their concentrations fluctuated seasonally and in response to nitrogen fertilization, but no effects of low temperature on the dehydrins of seedlings were observed. A 60-kDa dehydrin was associated with cold acclimation in the bud and bark tissues of mature trees and in the needles of seedlings. In the needles of mature trees, this dehydrin was associated with springtime desiccation, which was detected as a significant decrease in the osmotic potential of needles. The quantity and quality of soluble proteins altered seasonally in Scots pine tissues, but low temperature treatment alone did not have any effect on the proteins. Soluble protein concentration increased during autumn and decreased in spring in buds and bark, but not in the needles of mature trees. In needles of seedlings, however, protein concentrations altered seasonally. Several proteins, of varying molecular weights, were more abundant in winter in all the tissues studied and some increased in concentration in the nitrogen-fertilized seedlings. The role of these proteins as a storage reserve in Scots pine is discussed. The osmotic potential of needles showed seasonal fluctuation, being high in the summer and low during the winter. Low temperature treatment decreased the osmotic and water potential of needles and increased the concentrations of soluble sugars in seedlings. Based on carbohydrate analyses, the metabolism of seedlings acclimated to low temperature in less than ten days. Nitrogen fertilization increased the content of total nitrogen and the soluble protein concentrations in the needles of seedlings and the growth both in the mature trees and seedlings. Although the frost resistance showed no response to nitrogen-fertilization, the soluble proteins and dehydrins were affected in a manner that suggested an earlier growth resumption of spring in the fertilized trees.

O objetivo do presente trabalho foi avaliar o efeito de aditivos químicos sobre as perdas de matéria seca, composição química, valor nutritivo e estabilidade aeróbia da cana-de-açúcar in natura ou ensilada. No primeiro experimento, a cana-de-açúcar foi ensilada em silos laboratoriais. O experimento foi desenvolvido em delineamento experimental inteiramente casualizado com quatro repetições por tratamento. Os tratamentos avaliados foram: L. buchneri, cal virgem e calcário em doses de 1,0 e 1,5% da MV e gesso a 1,0% da MV, diluídos em 40L de água por tonelada de massa verde. Após a abertura dos silos, foram realizadas avaliações de perdas, estabilidade aeróbia, valor nutritivo e composição química. Os tratamentos contendo fontes de CaO ou CaCO3 apresentaram maior recuperação de matéria seca e menores perdas totais e gasosas. Nesses tratamentos também foram observados menor teor de etanol e maior concentração de ácido lático e de carboidratos solúveis. Para as variáveis de valor nutritivo, as silagens tratadas com esses aditivos apresentaram alto teor de cinzas, menor teor de fibra, maior coeficiente de digestibilidade e pequena alteração da fração protéica. As silagens de cana-de-açúcar com gesso ou L. buchneri apresentaram desempenho semelhante a silagem controle para as variáveis acima mencionadas. No ensaio de estabilidade aeróbia, a silagem aditivada com 1,5% de cal virgem apresentou desempenho superior e semelhante as silagens com L. buchneri e gesso. De forma geral, durante a fase anaeróbia as silagens tratadas com fontes de CaO ou CaCO3 apresentaram desempenho superior. Entretanto, na fase aeróbia, somente o tratamento contendo 1,5% de cal virgem manteve desempenho satisfatório. O segundo experimento avaliou o tratamento em montes da cana-de-açúcar picada in natura com doses de cal virgem durante dez dias de exposição aeróbia. O experimento foi realizado em delineamento inteiramente casualizado com quatro repetições por tratamento e em arranjo fatorial 2x4 com medidas repetidas no tempo. O fatorial foi composto por dois modos de aplicação e quatro doses do aditivo (0, 0,5, 1,0 e 1,5% da MV). Durante o ensaio foram realizadas avaliações de estabilidade aeróbia, valor nutritivo e composição química. Para as variáveis de estabilidade aeróbia, a utilização de cal virgem foi efetiva em evitar o aquecimento da massa de forragem e reduzir as perdas de matéria seca. Para a avaliação químico-bromatológica, não foi constatada diferença nos teores de CHO´S entre os tratamentos. O tratamento da cana-de-açúcar com cal virgem elevou o pH e a fração mineral da forragem. Os maiores teores de proteína bruta foram observados para a forragem não aditivada, contudo os valores obtidos para os demais tratamentos estão dentro da amplitude relatada na literatura. Doses de 1,0% e 1,5% do aditivo foram efetivas em evitar a elevação nos teores de FDN e FDA da canade- açúcar. A fração hemicelulose sofreu solubilização parcial imediatamente após a aplicação do aditivo. Os maiores coeficientes de DVIVMS e DVIVMO foram observados para as doses altas do aditivo, no modo de aplicação a seco, principalmente nas primeiras horas após o tratamento.
The objective of this trial was to evaluate the effects of chemical additives over the dry matter losses, chemical composition, nutritive value and aerobic stability of green chopped and ensiled sugarcane. In the first trial, the sugar cane was ensiled in experimental silos. The trial was carried out in a completely randomized experimental design with four replicates per treatment. The treatments evaluated were: L. buchneri, CaO and CaCO3, 1.0 e 1.5% and Ca(SO4)2, 1.0% (wet basis), all of them diluted to 40L of water per ton of fresh forage. After the silos were opened, the following variables were analyzed: losses, aerobic stability, nutritive value and chemical composition. Higher recovery rates and lower dry matter losses and gaseous production were observed for the silages containing CaO or CaCO3. In these treatments were also observed lower ethanol production and higher lactic acid and water soluble carbohydrates contents. The analysis of nutritive value showed that the utilization of CaO and CaCO3 increased the ash content, diminished the fibrous portion, improved the organic and dry matter digestibility and resulted in small changes of the crude protein content. The utilization of L. buchneri and Ca(SO4)2 resulted in silages similar to the control treatment for these variables. In the aerobic stability assay, only the silage containing 1.5% of CaO maintained the best performance. The silages treated with L. buchneri or Ca(SO4)2 showed similar performance. In summary, the silages treated with CaO or CaCO3 showed the best performance in the anaerobic phase and in the aerobic assay, only the treatment containing 1.5% of CaO maintained the positive performance across both assay. In the second trial, the green chopped sugar cane was treated with doses of CaO in an aerobic assay during ten days. The trial was carried out as a completely randomized experimental design with four replicates in a factorial design with repeated measures. The factorial was composed by two application methods and by increasing doses of CaO (0, 0.5, 1.0 e 1.5% in FF). The following variables were analyzed during the assay: aerobic stability, nutritive value and chemical composition. During the aerobic assay, the treatment with CaO reduced the heating and the dry matter losses in fresh sugar cane. For the chemical composition and nutritive value, there were no differences between treatments for the water soluble carbohydrates concentration. The utilization of CaO increased the pH and ash content of forages. Higher levels of crude protein were observed for the control forage, however the utilization of CaO did not reduced significantly the crude protein value. Doses of 1.0 and 1.5% of CaO inhibited the NDF and ADF uprising contents in the fresh sugar cane. The hemicellulose portion was solubilized immediately after the addition of CaO. Higher IVDMD and IVOMD coefficients were observed for the forage treated with 1.0% of CaO applied dried, mainly during the period immediately after treatment.

When plants are exposed to multiple environmental stress factors, one form of stress can affect the response to another stress. This study used seedlings of a new cultivar of wheat(Triticum aestivum L. cv. 1862), grown under factorial combinations of two levels of ultraviolet-B (UV-B)radiation, two salinity regimes and two levels of iron treatment in chelator-buffered nutrient solutions in a growth chamber. A number of morphological and physiological measurements were made. The accumulation of chlorophyll, UVabsorbing compounds and proline in shoots, as well as phytosiderophores (PSs) in root exudates were measured. Feed value measurements included crude protein, water-soluble carbohydrates, acid detergent fibre and Fe in shoots and roots. After 21 days of stress exposure, results showed that Fe deficiency and NaCl stress generally decreased plant growth and function as well as nutritive value, but increased plant biochemical protection traits such as proline accumulation (16.3 fold under salinity stress) and release of PSs (2.4 fold under Fe deficiency). Interestingly, UV-B radiation affected belowground parameters, inducing a 47% reduction in PS release, together with decreasing root DM by 9% and Fe concentration in roots by 7%. When Fe deficiency and NaCl stress were combined, the results showed a decrease in PS release by 3.5 fold compared to unstressed plants. UV-B radiation synergistically increased UV-absorbing compound levels in combination with Fe deficiency, compared to plants grown under optimal Fe levels. This stress combination also resulted in a cumulative effect by decreasing Fe concentration in shoots and roots. However, salt stress did not interact with UV-B radiation for any of the traits measured. In addition, some three-way interactions were noted, with the Fe x NaCl x UV-B stress combination slightly decreasing PS release and resulting in a cumulative effect by decreasing Fe concentration in roots. In conclusion, this study found that aboveground stress factors such as UV-B can affect important aspects of belowground plant function, and that Fe deficiency can interact with UV-B and salinity stress in modifying plant responses to either stress alone.

En Europe, les prairies permanentes représentent l'une des principales formes d'utilisation des terres. La durabilité des services rendus par ces écosystèmes est étroitement liée à la structure et au fonctionnement des communautés végétales qui les composent. La stabilité des processus écosystémiques, sous l'impact des fluctuations environnementales, va alors dépendre des mécanismes de résistance et de récupération propres à ces communautés. Les risques d'apparition d'extrêmes climatiques liés à l'évolution du climat, rendent nécessaire une adaptation des agro-écosystèmes à cette fluctuation climatique accrue. Cela implique de mieux comprendre les mécanismes par lesquels la variabilité du climat influe sur le fonctionnement et la structure des communautés végétales, et comment les pratiques agricoles impactent ces réponses. Cette thèse à pour objectif d'évaluer la vulnérabilité des prairies permanentes à un extrême climatique combinant une canicule et une sécheresse, dans un contexte de changement climatique. Afin d'identifier et de caractériser les mécanismes intrinsèques de la résistance à la sécheresse des communautés végétales, une démarche expérimentale mobilisant les concepts de l'écologie fonctionnelle a été développée. Les effets de la variabilité climatique sur la structure (diversité, composition) et le fonctionnement des communautés végétales ont d'abord été analysés in situ pendant 3 ans, après simulation d'une canicule-sécheresse dans les conditions climatiques actuelles et sous climat modifié (réchauffement et réduction des précipitations). Pour évaluer l'influence de la gestion sur la réponse des communautés végétales aux perturbations climatiques, deux fréquences de fauches ont été appliquées. Ce travail présente l'originalité d'avoir étudié conjointement le fonctionnement aérien et souterrain de la végétation. Sont considérées la production de biomasse, la démographie et la durée de vie des racines, afin de déterminer le rôle du système racinaire dans la résistance et la récupération des communautés végétales après une canicule sécheresse. Nous montrons un effet direct de l'extrême climatique sur la sénescence aérienne et la croissance racinaire dans les deux régimes de fauches. En réponse à un déficit hydrique modéré, la stratégie d'évitement au stress par le maintien de la croissance racinaire a été favorisée par des fauches non fréquentes. A l'automne suivant, les précipitations ont permis un reverdissement rapide de la couverture végétale et la production de nouvelles racines. Une baisse significative de la production de biomasse aérienne annuelle sous climat modifié, et suite à l'application de l'extrême climatique, a été observée pendant les 3 années d'expérimentation. En revanche, la production racinaire n'a pas été significativement affectée. Néanmoins une acclimatation de la croissance racinaire a été mise en évidence un an après l'extrême, en particulier dans les communautés de fauches non fréquemment. Ces changements de fonctionnement aériens et souterrains peuvent s'expliquer en partie par des modifications de la composition botanique. De plus, en réponse aux perturbations climatiques, la mortalité racinaire a été interrompue. Ces résultats inattendus ont donc entrainé une augmentation de la durée de vie des racines et suggèrent un effet négatif sur le turnover racinaire et les cycles biogéochimiques. Une expérimentation complémentaire à l'étude in situ a été menée en conditions semicontrôlées pour déterminer les mécanismes intrinsèques de la résistance à la sécheresse de la prairie permanente. Des traits morphologiques et physiologiques, aériens et souterrains, ont été mesurés sur des monocultures de sept populations prairiales en conditions optimales, puis en conditions de sécheresse afin de caractériser leurs stratégies de survie. Les résultats ont mis en évidence le rôle du système racinaire dans la survie des plantes. (...)

Wong Ka-kei.
Thesis submitted in: December 2004.
Thesis (M.Phil.)--Chinese University of Hong Kong, 2005.
Includes bibliographical references (leaves 123-139).
Abstracts in English and Chinese.
THESIS COMMITTEE --- p.i
ACKNOWNLEDGEMENT --- p.ii
ABSTRACT (ENGLISH VERSION) --- p.iii
ABSTRACT (CHINESE VERSION) --- p.v
LIST OF TABLES --- p.ix
ABBREVIATIONS --- p.xiii
Chapter CHAPTER 1 --- INTRODUCTION --- p.1
Chapter 1.1 --- Edible mushrooms --- p.1
Chapter 1.1.1 --- Classification and terminology --- p.1
Chapter 1.1.2 --- Mode of nutrition --- p.3
Chapter 1.1.3 --- World consumption --- p.3
Chapter 1.1.4 --- Nutritional values of edible mushroom --- p.6
Chapter 1.1.5 --- Medicinal values of mushrooms --- p.7
Chapter 1.2 --- Mushroom mycelium --- p.11
Chapter 1.2.1 --- Uses and applications --- p.11
Chapter 1.2.2 --- Submerged fermentation (SmF) --- p.12
Chapter 1.2.3 --- Factors affecting the growth of mycelium in submerged fermentation --- p.14
Chapter 1.2.3.1 --- Nutritional requirements - Carbon sources --- p.14
Chapter 1.2.3.2 --- Nutritional requirements ´ؤ Nitrogen sources --- p.16
Chapter 1.2.3.3 --- Nutritional requirements ´ؤ Minerals --- p.16
Chapter 1.2.3.4 --- Environmental factors ´ؤ Temperature --- p.17
Chapter 1.2.3.5 --- Environmental factors - Aeration --- p.17
Chapter 1.2.3.6 --- Environmental factors - Agitation --- p.18
Chapter 1.2.4 --- Optimization of growth of mycelium and production of EPS --- p.18
Chapter 1.3 --- Mushroom polysaccharides --- p.21
Chapter 1.3.1 --- Biologically active mushroom polysaccharides --- p.21
Chapter 1.3.2 --- Chemical structures of mushroom polysaccharides --- p.21
Chapter 1.3.2.1 --- β-glucans --- p.23
Chapter 1.3.2.2 --- α-glucans --- p.25
Chapter 1.3.2.3 --- Mannans --- p.26
Chapter 1.3.2.4 --- Protein-bound polysaccharides --- p.26
Chapter 1.3.2.5 --- Other heteroglycans --- p.28
Chapter 1.4 --- Mushrooms under investigation --- p.28
Chapter 1.4.1 --- Pleurotus tuber-regium (Fr.) Sing. (PTR) --- p.28
Chapter 1.4.2 --- Agrocybe cylindracea (AC) --- p.30
Chapter 1.4.3 --- Grifola frondosa (GF) --- p.31
Chapter 1.5 --- Objectives and experimental design --- p.32
Chapter CHAPTER 2 --- MATERIALS AND METHODS --- p.35
Chapter 2.1 --- Source of mushroom mycelium --- p.35
Chapter 2.2 --- Effect of different carbon sources on submerged fermentation --- p.37
Chapter 2.2.1 --- Production of mycelium by submerged fermentation using 250 mL and 1L shake-flasks --- p.37
Chapter 2.2.2 --- Scale-up production of mycelium of PTR using fermentor --- p.39
Chapter 2.2.3 --- Concentration of dissolved oxygen in 250 mL and 1L shake-flasks. --- p.39
Chapter 2.3 --- Isolation and fractionation of mushroom polysaccharides --- p.40
Chapter 2.3.1 --- Isolation of exo-polysaccharides (EPS) from culture medium by ethanol precipitation --- p.40
Chapter 2.3.2 --- Isolation of EPS from culture medium by ultra-filtration --- p.40
Chapter 2.3.3 --- Hot water extraction of PTR mycelium --- p.41
Chapter 2.3.4 --- Fractionation of HWE by fractional ethanol precipitation --- p.41
Chapter 2.4 --- Chemical composition of HWE and EPS --- p.42
Chapter 2.4.1 --- Phenol-sulphuric acid method --- p.42
Chapter 2.4.2 --- Modified Lowry method --- p.43
Chapter 2.4.3 --- Monosaccharide composition analysis of HWE and EPS --- p.43
Chapter 2.4.3.1 --- Acid depolymerization --- p.43
Chapter 2.4.3.2 --- Neutral sugar derivatization --- p.44
Chapter 2.4.3.3 --- Determination of neutral sugar composition by gas chromatography (GC) --- p.45
Chapter 2.4.3.4 --- Uronic acid content --- p.46
Chapter 2.5 --- Structural studies of HWE and EPS --- p.47
Chapter 2.5.1 --- High Pressure Liquid Chromatography (HPLC) --- p.47
Chapter 2.5.2 --- Methylation study and gas chromatography- mass spectrometry (GC-MS) --- p.48
Chapter 2.5.2.1 --- Preparation of dry dimethyl sulfoxide (DMSO) --- p.48
Chapter 2.5.2.2 --- Preparation of methylsulfinyl methyl sodium (CH3SOCH2-Na+) --- p.48
Chapter 2.5.2.3 --- Methylation --- p.49
Chapter 2.5.2.4 --- Extraction of methylated polysaccharide --- p.49
Chapter 2.5.2.5 --- Acid depolymerization and preparation of aditol acetate derivatives --- p.50
Chapter 2.5.2.6 --- Determination of partially methylated alditol acetates (PMAAs) by gas chromatography-mass spectrometry (GC-MS) --- p.50
Chapter CHAPTER 3 --- RESULTS AND DISCUSSION --- p.51
Chapter 3.1 --- "Production of mycelium and EPS of PTR, AC and GF by submerged fermentation in 250 mL shake-flask with liquid medium containing different carbon sources" --- p.51
Chapter 3.1.1 --- "Mycelial biomass production of PTR, AC and GF" --- p.51
Chapter 3.1.2 --- "Production of EPS of PTR, AC and GF" --- p.57
Chapter 3.1.3 --- "Characterization of EPS of PTR, AC and GF" --- p.62
Chapter 3.1.3.1 --- Carbohydrate and protein content --- p.62
Chapter 3.1.3.2 --- Monosaccharide composition --- p.67
Chapter 3.1.4 --- Summary --- p.72
Chapter 3.2 --- "Production of mycelium, EPS of PTR by submerged fermentation in 1L shake-flask and 8L fermentor with liquid medium containing different carbon sources" --- p.75
Chapter 3.2.1 --- Mycelial production of PTR --- p.75
Chapter 3.2.2 --- EPS Production of PTR --- p.80
Chapter 3.2.3 --- Chemical characteristics of EPS of PTR --- p.83
Chapter 3.2.3.1 --- Carbohydrate and protein content --- p.83
Chapter 3.2.3.2 --- Monosaccharide composition --- p.85
Chapter 3.2.4 --- Structural characteristics of EPS of PTR --- p.87
Chapter 3.2.4.1 --- Molecular weight of EPS of PTR by HPLC --- p.87
Chapter 3.2.4.2 --- Glycosyl linkages of EPS of PTR by GC-MS of PMAA --- p.90
Chapter 3.2.5 --- Summary --- p.93
Chapter 3.3 --- Hot water extraction of mycelium of PTR from the scale-up submerged fermentation in 1L shake-flask and 8L fermentor with liquid medium containing different carbon sources --- p.95
Chapter 3.3.1 --- Yield of hot water extract (HWE) of mycelium of PTR --- p.95
Chapter 3.3.2 --- Chemical characteristics of HWE of PTR --- p.101
Chapter 3.3.2.1 --- Carbohydrate and protein content --- p.101
Chapter 3.3.2.2 --- Monosaccharide composition --- p.104
Chapter 3.3.3 --- Structural characteristics of HWE of PTR --- p.112
Chapter 3.3.3.1 --- Molecular weight of HWE of PTR by HPLC --- p.112
Chapter 3.3.3.2 --- Glycosyl linkages of HWE of PTR by GC-MS ofPMAA --- p.116
Chapter 3.3.4 --- Summary --- p.119
Chapter CHAPTER 4 --- CONCLUSIONS AND FUTURE WORKS --- p.120
Chapter 4.1 --- Conclusions --- p.120
Chapter 4.2 --- Future works --- p.121
REFERENCES --- p.123

博士
國立臺灣大學
化學研究所
92
Abstract This thesis consists of three parts. The first part is to develop metal ion chemosensors containing naphthyridine moiety; the second part is to design and synthesize water soluble carbohydrate receptors; the last part is to characterize the second-order nonlinear optical properties of thiophene conjugated heterocycles. Part I: Development of metal ion chemosensors containing naphthyridine moiety Up to now only a few chemosensors of heavy (transition) metal ions utilize fluorescence enhancement as the detection mechanism. Our research objective is to develop efficient fluorescent chemosensors and colorimetric chemosensors for transition metal ions (e.g. Hg2+ and Cu2+) with high sensitivity and selectivity. A series of intrinsic chemosensors p-CHEAN (1), p-BHEAN (2), m-CHEAN (3) and m-BHEAN (4) were thus designed and synthesized by the linkage of 1,8-naphthyridines as donors and bis(hydroxyethyl)aminophenyls as acceptors through triple bonds. The para-substituted chemosensors p-CHEAN and p-BHEAN displayed drastic color changes on addition of mercuric ion in an excellent selectivity in DMSO/H2O (1:1) solution. When these chemosensors bound with mercury ion, an intramolecular charge transfer occurred to account for the color changes. These colorimetric sensors provide a fast and easy method for the direct naked-eye sensing for mercuric ion. In comparison with p-CHEAN, the molecular sensor p-BHEAN of DAD type containing two arms with the bis(hydroxyethyl)amino donor groups at the para position exhibited the absorption band in the visible region, and offered two-stage changes p-BHEAN sensor to detect mercuric ion. On the other hand, the meta-substituted chemosensors m-CHEAN and m-BHEAN showed profound fluorescence enhancements on complexation with cupric ion in CH3CN. These fluorescence sensors were highly selective for Cu2+ ion in the presence of other metal ions (Ni2+, Co2+, Mg2+, Ca2+, Ba2+, Cd2+, Mn2+, and Pb2+). Part II: Design and synthesis of water soluble carbohydrate receptors The saccharide receptor contained the core structure of 1,8-naphthyridine which was linked via ethynyl bridges to two end groups of phenols. The BHPN molecule was synthesized,and found to bind strongly with various octyl glycosides via multiple hydrogen bondings in CH2Cl2. In order to develop effective chemosensors for saccharides in aqueous medium, we attempted to incorporate water-soluble moieties, derivatives with functional groups such as nitro group, carboxylic acid and sulfonic acid, to obtain the BHPN enhanced solubility in water. We have synthesized p-NO2-BHPN and m-CO2CH3-BHPN compounds successfully. However we encountered some problems in separation of the desired products due to their water-soluble properties. Part III: The second-order nonlinear optical properties of thiophene conjugated heterocycles The nonlinear optical properties of bicyclic thiophenes Y1-Y4 with ��-conjugation are described in this part. The aim is to realize whether the lost aromatic resonance energy during the process of polarization can be totally compensated by the newly formed aromatic resonance stabilization of bicyclic thiophene. We thus synthesized the control molecules 89, 90 and 91 which with the same donor and acceptor but without bicyclic structure to compare their nonlinear optics. From the results of ��0 measurements by EFISH we found there were no apparent relationship between ��0 value and the molecular structure.

Grünlandfutter mit einem hohen Ertrag und gutem Futterwert ist eine Grundvoraussetzung für die effiziente Produktion von wiederkäuenden Nutztieren. Im Zuge des prognostizierten Klimawandels werden sich die Niederschlagsmuster ändern und das Auftreten von Extremwetterereignissen, wie temporärer Trockenheit, wird sich erhöhen. Besonders produktives Grünland benötigt aber eine ausreichende und regelmäßige Wasserversorgung während der Wachstumsperiode. Deshalb werden die Futterproduktion von Grünland, die Ertragsstabilität und der Futterwert von temporärer Trockenheit beeinflusst werden. Aus diesem Grund sind Anpassungsstrategien nötig, um eine zukünftige und nachhaltige Grünlandfuttererzeugung zu sichern. Erhöhte pflanzliche Biodiversität wird oft als Möglichkeit angesehen, Funktionen von Ökosystemen, wie Produktivität und Futterwert, im Grünland zu verbessern. Es gibt eine fortlaufende Diskussion wie eine erhöhte Artenzahl auf Stress, besonders Trockenstress, reagiert und wie dabei Produktivität, Futterwert und Wassernutzung beeinflusst werden. Andere Untersuchungen zeigten, dass Artidentität und die Zusammensetzung der funktionellen Gruppen wichtige Faktoren für Produktivität und Futterwert sind. Auf Grund dessen haben wir von Juli 2009 bis Juni 2011 ein Trockenstressexperiment in einer Vegetationshalle durchgeführt. Verschiedene temporäre Trockenstressereignisse wurden in drei Aufwüchsen in zwei Vegetationsperioden durchgeführt. Die klimatischen Verhältnisse in der Vegetationshalle folgten normalen saisonalen Verläufen mit Frost im Winter und höheren Temperaturen im Sommer. Trockenstress wurde induziert, indem, nach einer anfänglichen Bewässerung, die Wasserversorgung für einen bestimmten Zeitraum eingestellt wurde. Die Wasserverfügbarkeit des Bodens konnte dabei immer kontrolliert werden. Für das Experiment wählten wir ertragsstarke und landwirtschaftlich nutzbare Arten des Grünlands der gemäßigten Zonen aus. Die Arten wurden in Monokultur und Drei- sowie Fünfartenmischungen gesät und enthielten die funktionellen Gruppen Leguminose (Trifolium repens L.), Gras (Lolium perenne L., Dactylis glomerata L.) und Kraut (Plantago lanceolata L., Taraxacum officinale F.H. Wigg. agg.). Der von uns gewählt Umfang der Artenzahl zeigte schon in anderen Biodiversitätsexperimenten einen Einfluss auf die Produktion. Untersucht wurden die Effekte von Artenzahl und funktionellen Gruppen auf Ertrag, Ertragsstabilität, Wassernutzung und Futterwert (Rohprotein, wasserlösliche Kohlenhydrate, neutrale und saure Detergenzienfasern). Als Indikatoren für die Ertragsentwicklung und die agronomische Wassernutzungseffizienz (Verhältnis von Ertrag zu Wasserverbrauch) dienten der Stickstoffertrag und die Stickstoffkonzentration der Bestände sowie δ13C Signaturen, sowohl mit unlimitierter Wasserversorgung als auch mit Trockenstress. Überdies führten wir 2009 ein Kurzzeitfeldexperiment auf einem alten Grünlandbestand auf dem Versuchsgut der Universität Göttingen in Reliehausen durch. In diesem Versuch wurde ebenso der Einfluss von Trockenstress und Artenzahl auf den Ertrag und die Wassernutzung untersucht. Unsere Daten zeigten, dass Trockenstress die Produktivität verringert und die Wassernutzung beeinflusst, beides abhängig von der Stärke des Stresses. Bei moderatem Stress war die agronomische Wassernutzungseffizienz unverändert oder stieg leicht an, bei starkem Stress verringerte sie sich jedoch. Der Stickstoffertrag und die Stickstoffkonzentration waren brauchbare Indikatoren für die agronomische Wassernutzungseffizienz, wohingegen δ13C weniger geeignet war. Die agronomische Wassernutzungseffizienz wurde von Stickstoff erhöht. Es gab keinen oder nur einen sehr geringen Einfluss von Trockenstress auf den Futterwert. Saisonale Effekte hatten mehr Einfluss auf den Futterwert. Allgemein scheint der Ertragsrückgang wichtiger als die Veränderungen des Futterwerts zu sein. Die Artenzahl beeinflusste den Futterwert und die Ertragsstabilität über die Vegetationsperiode nicht. Mit Hilfe des “sampling effect“ (Probennahmeeffekt) können der manchmal positive Einfluss der Artenzahl auf den Ertrag und die agronomische Wassernutzungseffizienz und der Rückgang dieses Einflusses unter Trockenheit erklärt werden. Mit erhöhter Artenzahl stieg der Anteil der leistungsfähigen, aber trockenheitssensitiven Leguminose. Weiterhin gab es einen Hinweis, dass die Artenzahl die Geschwindigkeit des Wasserverbrauchs erhöht. Die Ergebnisse des Feldexperiments bekräftigten die Befunde bezüglich der Effekte des Trockenstresses, des Ertrages und der Wassernutzung. Aus diesen Gründen kann die „insurance hypothesis“ (Versicherungshypothese), die besagt, dass eine erhöhte Artenzahl Ökosystemfunktionen gegenüber Umweltveränderungen stabilisieren kann, nicht bestätigt werden. Jedoch waren die funktionellen Gruppen wichtige und bestimmende Faktoren der Leistung unter nicht Wasser limitierten Bedingungen und Trockenstress. Die Leguminose hatte besonders auf Ertrag, agronomische Wassernutzungseffizienz und Rohprotein einen positiven Einfluss, jedoch erhöhte sie auch den Wasserverbrauch und die saisonale Variabilität. Gräser stabilisierten den Ertrag und den Wasserverbrauch und erhöhten die wasserlöslichen Kohlenhydrate sowie die Faserfraktionen, während sie den Ertrag und die agronomische Wassernutzungseffizienz unter den stickstofflimitierten Bedingungen unseres Experiments verringerten. Die funktionelle Gruppe Kräuter zeigte ähnliche Ergebnisse bezüglich Ertrag und Wassernutzung, aber sie erhöhte das Rohprotein. Unsere Ergebnisse demonstrieren, dass die vorhergesagte Zunahme von Trockenstressereignissen die Produktion reduzieren und die Wassernutzung ändern wird. Änderungen im Futterwert werden dabei weniger wichtig als der Ertragsrückgang sein. Für die Produktion, die Wassernutzung und den Futterwert wird die Artenanzahl weniger relevant sein als die funktionelle Zusammensetzung von Grünland. Deshalb wird eine angepasste Grasnarbenzusammensetzung für die Sicherung der Produktion von wiederkäuenden Nutztieren unter den Bedingungen des erwarteten Klimawandels Bedeutung erlangen.