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Konjac glucomannan (KGM), the main biologically active constituent of konjac flour extracted from corms of Amorphophallus konjac (konjac), can be used to prepare functional foods and may also have potential as a pharmaceutical product to combat obesity. The current study employed three experimental approaches to study the biology and chemistry of konjac, namely (1) glasshouse experiments to study the morphogenesis, growth and productivity of konjac plants, (2) a histological and immunocytochemical investigation of the localisation and developmental regulation of the deposition and metabolism of KGM in developing corm tissues, and (3) a comparative study of methodologies for the extraction and analysis of KGM. The current data demonstrated a morphological and functional separation between the ventral and dorsal regions of corms. The ventral region appeared to function as a source during the initial period of shoot development, while the dorsal region appeared to operate as a sink after the development of mature canopy. Once the corm reached maturity, both an inflorescence and a leaf were produced within a single season. It has also been demonstrated that the age of the ‘mother’ corm is an important factor affecting the quality of offsets produced. An anti-mannan antiserum detected a temporally regulated pattern of mannan epitope production within glucomannan idioblasts in developing corm tissues, with increased expression as the corm approached maturity/dormancy. The current observations also suggest that the mobilization of KGM initiates at the periphery of the corm and proceeds inwards towards the centre of the corm. Compositional analysis showed that the purified konjac flour (PKF) produced using a modified extraction procedure contained 92% glucomannan, with a weight average molecular weight (Mw), polydispersity index (PDI) and degree of acetylation (DA) of 9.5 ± 0.6 x 105 gmol-1, 1.2 and 2.8 wt. %. These data, plus Fourier-transform infrared spectral (FTIR) and zero shear viscosity analyses of the extract (PKF) were all consistent with the literature. Comparison of three existing methodologies for the quantitative analysis of the KGM content, namely 3,5-dinitrosalicylic acid (3,5-DNS), phenol-sulphuric acid and enzymatic colorimetric assays; indicated that the 3,5-DNS colorimetric assay was the most reproducible and accurate method, with a linear correlation coefficient of 0.997 and recoveries between 97% and 103% across three spiking levels of starch. In summary, this study has provided a better understanding of aspects of the biology and cultivation of A. konjac and has also produced methodologies which can be used as the basis for an improved good laboratory practice (GLP) for the commercial extraction and analysis of this multifunctional natural polymer.

Externally initiated o-tolyl initiated poly(3-hexylthiophene) (P3HT) was synthesized according to Grignard metathesis polymerization at varying chain length to compare number average molecular weights (Mn) obtained by gel permeation chromatography (GPC) and 1H NMR end group analysis. The extent of overestimation by GPC (1.3) was determined to be lower than previously reported for low Mn polymers. However, an apparent GPC quantification limit was observed as NMR Mn correlated well to predicted results. Static light scattering studies on high Mn polymers provided evidence that the true molecular weight was more similar to GPC-derived Mn. Despite nearly 100% external initiation efficiency, at a certain Mn limit new uninitiated chains may be synthesized. It is suggested that the synthesis of externally initiated P3HT should be limited to Mn below 40 kDa to ensure fully externally initiated chains. A proposal for the synthesis of externally initiated macrocyclic P3HT will also be discussed.

In den letzten 15 Jahren wurde in einigen Mittelgebirgsregionen Zentraleuropas ein regional un-terschiedlich starker Anstieg der Konzentration gelösten organischen Kohlenstoffes (DOC) in Oberflächengewässern festgestellt. Besonders betroffen von dieser Entwicklung sind für die Trink-wasserproduktion genutzte Talsperren. Durch den erhöhten DOC-Gehalt wird die Trinkwasser-aufbereitung nicht nur kostenintensiver, sondern bekommt auch zunehmend Probleme bei der Wahrung der Trinkwasserqualität. Die Quellen des DOC sind in den Einzugsgebieten befindliche Moore und hydromorphe Nassstandorte. Die Ursachen für den in den vergangenen Jahren doku-mentierten Mehraustrag sind äußerst komplex und beinhalten sowohl klimatische als auch nut-zungsbedingte Veränderungen. Ziel der vorliegenden Arbeit ist, den Charakter des DOC näher zu bestimmen, um die für die Wasseraufbereitung problematischen Fraktionen zu benennen und Ansatzpunkte für regulierende Maßnahmen aufzuzeigen. Die Charakterisierung erfolgte an einem LC-OCD-System (Liquid Chromatography – Organic Carbon Detection) am Beispiel der drei Tal-sperrensysteme Muldenberg, Carlsfeld (Westerzgebirge) und Fláje (Osterzgebirge, Tschechien). Die Talsperren weisen unterschiedliche DOC-Gehalte auf. Die Ergebnisse zeigen, dass der DOC aller Untersuchungsgebiete sowohl in den Zuflüssen, dem Talsperrenwasser bzw. Rohwasser als auch dem Reinwasser der Wasserwerke von Huminstoffen dominiert wird. DOC-Schwankungen sind folglich auf Schwankungen der Huminstoffkonzentrationen zurückzuführen. In den Zuflüs-sen treten die höchsten Huminstoffkonzentrationen während der Schneeschmelze im Frühjahr und bei Starkniederschlägen im Sommer und Herbst auf. Niedrige Konzentrationen sind an Bo-dengefrornis oder Trockenphasen im Sommer gebunden. In den Talsperren tritt im Sommer eine Schichtung der Huminstoffe auf, bei der an der Oberfläche durch photolytischen Abbau niedrige-re Konzentrationen und in Abhängigkeit von der Talsperrentiefe durch die Einschichtung der Zuflüsse am Grund höhere Konzentrationen auftreten. Die Verteilung im Winter ist allein von der Einschichtung der Zuflüsse abhängig. Die Verteilung der Building Blocks (Huminstoffhydrolysate) ist im Sommer der der Huminstoffe entgegengesetzt, da sich beim photolytischen Abbau von Hu-minstoffen Building Blocks bilden. Während der Zirkulationen sind die Konzentrationen der Hu-minstofffraktionen im gesamten Tiefenprofil gleich. In den Talsperren Muldenberg und Carlsfeld wurde im Untersuchungszeitraum unter Berücksichtigung der technischen Gegebenheiten und anderer Wassergütekriterien der optimale Rohwasserentnahmehorizont (niedrigstmögliche Hu-minstoffkonzentration) gewählt. In der Talsperre Fláje könnte die Rohwasserqualität durch Instal-lation eines schwenkbaren Entnahmerohres erheblich verbessert werden. In den Wasserwerken sind die Huminstofffraktionen mit abnehmender Molekülgröße schwieriger zu entfernen. Die relativ niedermolekularen Building Blocks sind die am schwersten entfernbaren DOC-Bestandteile. Auf Grundlage mathematischer Beziehungen zu SAK254 bzw. DOC wurde ein Programm (DOCQuaC – DOC-Quality Calculator) entwickelt, mit dessen Hilfe die Huminstofffraktionen über diese Grundparameter ermittelt werden können. Neben der Fraktionsquantifizie-rung besteht im Programm die Möglichkeit zur Berechnung der Eliminierungsleistung, so dass beispielsweise nach der Durchführung einer Maßnahme zur Verbesserung der DOC-Entfernung eine unmittelbare Aussage über den Effekt auf die Fraktionen vorliegt. / For the last 15 years a change of Dissolved Organic Carbon (DOC) has been taking place in surface waters of Middle European Highlands. The degree of this increase is regionally dependent. The reasons as well as the consequences of this development are of high complexity. The changes are expressed in an increase of middle DOC values and, additionally, an increase of annual changes. Reservoirs, used for drinking water production, are particularly affected, because the heightened DOC content increases the costs for drinking water treatment, and currently it is not possible to maintain a good drinking water quality. The main DOC source are peat bogs, situated in the catchments. The cause of the increasing DOC output from peat bogs are very complex and contain changes as well in climate as in land use. The aim of this presented dissertation was to gain more information about the character of DOC, so that those fractions can be determined which are problematically to remove inside the waterworks. On that base it should be possible to find some starting points for more regulating measures. The analytical characterisation was carried out by the help of a LC-OCD-System (Liquid Chromatography – Organic Carbon Detection), exemplary for the reservoir systems Muldenberg, Carlsfeld (Western Ore Mountains) and Fláje (Eastern Ore Mountains, Czech Republic). Although the DOC concentrations are very different in the reser-voirs, it was always dominated by humic substances, namely as well in the tributaries, as in the raw and treated water. Thus changes in the DOC concentration are due to changes in the concen-tration of humic substances. In spring and summer occur the highest concentrations of humic substances in the tributaries. Low concentrations are linked with frost in winter or dry periods in summer. In the reservoirs in summer a stratification of humic substances shapes up, with lower concentration near the water surface (caused by photolytical degradation) and accordingly higher concentration near the ground (layering of influxes). Distribution in winter only depends on the layering of the influxes. In summer the concentration of Building Blocks (humic substance hydro-lysates) is opposite to that of humic substances, because of the creation of Building Blocks at the photolytical degradation. During circulation the concentration of all humic substance fractions are equal in each reservoir layer. In the reservoirs Muldenberg and Carlsfeld, a further optimisation of the raw water withdrawal horizon is not possible. In the reservoir Fláje the raw water could be much improved by installing a movable withdrawal device. With decreasing molecular size the elimination of the humic fractions gets more difficult in the waterworks. Most difficult to eliminate are Building Blocks. On the basis of the mathematical cor-relation between humic fractions and the SAC254 and DOC a program (DOCQuaC – DOC-Quality Calculator) has been developed, which enables die calculation of humic concentrations by enter-ing these general parameters. In addition to the calculation of the concentrations it is possible to calculate the elimination capacity for the humic fractions. Thus the effects of measures on the humic fractions, which could be done for optimisation of the elimination capacity, can be imme-diately observed.

The degradation of wool keratin under conditions relevant to those of wool dyeing was investigated using the techniques of gel permeation chromatography (GPC), ion exchange gel chromatography, and amino acid analysis. Physical testing of the treated and untreated wool was also carried out to determine the physical changes occurring, parameters used being percentage elongation at the break, and the breaking strain of the fibre. Samples of wool keratin were immersed in various aqueous solutions at 1000C for 24 hours and the filtered, aqueous, oxidised extracts were analysed* The solutions used varied only in the dye, or dye intermediate present in the treatment solution. All treatment baths contained 10% owf 1.02 x 10 -2 MSulphuric VI acid; 10%owf 7.04x 10 -3 MSodium sulphate VI ; A 100 :1 liquor ratio was used in each case. Some of the dye intermediates showed a marked catalytic effect, particularly in their effect on breaking strain, a decrease of 40% in some cases. The GPC profiles of the extracted proteins were examined in detail and compared against previous workers' results. An explanation of the behaviour of the dyes and intermediates was proposed. The amino acid composition data of the extracted and fractionated proteins were compared against various morphological components extracted by other workers, as was the total gelatin obtained from each treatment.

Externally initiated o-tolyl initiated poly(3-hexylthiophene) (P3HT) was synthesized according to Grignard metathesis polymerization at varying chain length to compare number average molecular weights (Mn) obtained by gel permeation chromatography (GPC) and 1H NMR end group analysis. The extent of overestimation by GPC (1.3) was determined to be lower than previously reported for low Mn polymers. However, an apparent GPC quantification limit was observed as NMR Mn correlated well to predicted results. Static light scattering studies on high Mn polymers provided evidence that the true molecular weight was more similar to GPC-derived Mn. Despite nearly 100% external initiation efficiency, at a certain Mn limit new uninitiated chains may be synthesized. It is suggested that the synthesis of externally initiated P3HT should be limited to Mn below 40 kDa to ensure fully externally initiated chains. A proposal for the synthesis of externally initiated macrocyclic P3HT will also be discussed.

Made available in DSpace on 2014-06-11T19:35:46Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-01-11Bitstream added on 2014-06-13T18:47:18Z : No. of bitstreams: 1 urban_vm_dr_arafo.pdf: 2869944 bytes, checksum: e7264bf2de7fc0a0dde924482741fd32 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Os objetivos deste estudo foram avaliar: 1. o efeito de tratamentos póspolimerização (MW-irradiação por energia de microondas e WB-imersão em água aquecida) sobre o grau de conversão (DC) de resinas acrílicas para reembasamento imediato (Ufi Gel hard-U, Kooliner-K e Tokuso Rebase Fast-T) e de uma resina acrílica para base de prótese (Lucitone 550-L), submetida a dois ciclos de polimerização (LS-curto e LL-longo) por espectroscopia FT-Raman; 2. o peso molecular (M w) do pré-polímero dos materiais U, K, T e L e das amostras polimerizadas da resina K (controle; MW e WB) por GPC; 3. o efeito de MW e WB na temperatura de transição vítrea (Tg) das resinas para reembasamento imediato (Duraliner II-D, K, New Truliner-N, U e T) e da resina para base de prótese (LS e LL) por DSC; 4. o efeito de WB na liberação de compostos residuais (isobutil metacrilato-IBMA, 1,6-hexanediol dimetacrilato-1,6-HDMA e DBNP-dibutil-n-ftalato) a partir das resinas para reembasamento imediato K, N, U e T para saliva artificial por CLAE; 5. o efeito de WB na liberação de produtos de degradação (ácido metacrílico-MA e ácido benzóico-BA) a partir das resinas para reembasamento imediato K, N, U e T para saliva artificial por CLAE. Amostras do grupo controle não foram submetidas a nenhum tratamento. Os resultados de DC (%) foram analisados pelo teste de Kruskal-Wallis ( =0,05). Os resultados de Tg (ºC) foram analisados pela análise de variância (ANOVA), seguido pelo teste de Tukey ( =0,05). Os resultados da liberação de monômero ' 224 residual e plastificante (μg/mL) foram submetidos aos testes de Wilcoxon ou de Mann-Whitney ( =0,05). Os resultados da liberação de produtos de degradação (μg/mL) foram submetidos aos testes de Wilcoxon, Mann-Whitney ou Kruskal- Wallis ( =0,05). Para as amostras do grupo controle, não houve diferenças significantes entre o DC das resinas U e LL e entre... / The aims of this study were to evaluate: 1. the effect of post-polymerization treatments (MW-microwave irradiation and WB-water-bath) on the degree of conversion (DC) of reline resins (Ufi Gel hard-U, Kooliner-K, and Tokuso Rebase Fast-T) and denture base resin (Lucitone 550-L), submitted to two polymerization cycles (LS-short and LL-long) by FT-Raman spectroscopy; 2. the molecular weight (M w) of the powder of U, K, T, and L materials and of K polymerized specimens (control; MW; and WB) by GPC; 3. the effect of MW and WB on the glass transition temperature (Tg) of the reline resins (Duraliner II-D, K, New Truliner-N, U and T) and the heat-polymerized resin (LS and LL) by DSC; 4. the effect of WB on the leaching of residual compounds (isobutyl methacrylate- IBMA, 1,6-hexanediol dimethacrylate-1,6-HDMA, and DBNP-dibutyl-nphthalate) from the reline resins (K, N, U, and T) in artificial saliva by HPLC; 5. the effect of WB on the leaching of degradation products (methacrylic acid-MA and benzoic acid-BA) from the reline resins K, N, U, and T in artificial saliva by HPLC. Control group specimens were left untreated. DC (%) data were analyzed using Kruskal-Wallis test (_=.05). Tg (ºC) data were analyzed using ANOVA/Tukey's test (_=.05). The results (æg/mL) of residual monomer and plasticizer leachability were submitted to Wilcoxon or Mann-Whitney tests (_=.05). The results (æg/mL) of degradation products leachability were submitted to Wilcoxon, Mann-Whitney or Kruskal-Wallis tests (_=.05). For DC control specimens, there were no significant differences between U and LL and among LL, K, and T. LS specimens had the highest DC. Only material K exhibited an increased DC after WB. All powders had M w from 4.0x105 to 6.5x105 and narrow M w distributions (2.1 to 3.6). Polymerization and post-polymerization produced K specimens with M w values similar to that of K powder...(Complete abstract, click electronic address below).

Made available in DSpace on 2014-10-09T12:41:42Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:07:07Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Resumo: Os objetivos deste estudo foram avaliar: 1. o efeito de tratamentos póspolimerização (MW-irradiação por energia de microondas e WB-imersão em água aquecida) sobre o grau de conversão (DC) de resinas acrílicas para reembasamento imediato (Ufi Gel hard-U, Kooliner-K e Tokuso Rebase Fast-T) e de uma resina acrílica para base de prótese (Lucitone 550-L), submetida a dois ciclos de polimerização (LS-curto e LL-longo) por espectroscopia FT-Raman; 2. o peso molecular (M w) do pré-polímero dos materiais U, K, T e L e das amostras polimerizadas da resina K (controle; MW e WB) por GPC; 3. o efeito de MW e WB na temperatura de transição vítrea (Tg) das resinas para reembasamento imediato (Duraliner II-D, K, New Truliner-N, U e T) e da resina para base de prótese (LS e LL) por DSC; 4. o efeito de WB na liberação de compostos residuais (isobutil metacrilato-IBMA, 1,6-hexanediol dimetacrilato-1,6-HDMA e DBNP-dibutil-n-ftalato) a partir das resinas para reembasamento imediato K, N, U e T para saliva artificial por CLAE; 5. o efeito de WB na liberação de produtos de degradação (ácido metacrílico-MA e ácido benzóico-BA) a partir das resinas para reembasamento imediato K, N, U e T para saliva artificial por CLAE. Amostras do grupo controle não foram submetidas a nenhum tratamento. Os resultados de DC (%) foram analisados pelo teste de Kruskal-Wallis ( =0,05). Os resultados de Tg (ºC) foram analisados pela análise de variância (ANOVA), seguido pelo teste de Tukey ( =0,05). Os resultados da liberação de monômero ' 224 residual e plastificante (μg/mL) foram submetidos aos testes de Wilcoxon ou de Mann-Whitney ( =0,05). Os resultados da liberação de produtos de degradação (μg/mL) foram submetidos aos testes de Wilcoxon, Mann-Whitney ou Kruskal- Wallis ( =0,05). Para as amostras do grupo controle, não houve diferenças significantes entre o DC das resinas U e LL e entre...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The aims of this study were to evaluate: 1. the effect of post-polymerization treatments (MW-microwave irradiation and WB-water-bath) on the degree of conversion (DC) of reline resins (Ufi Gel hard-U, Kooliner-K, and Tokuso Rebase Fast-T) and denture base resin (Lucitone 550-L), submitted to two polymerization cycles (LS-short and LL-long) by FT-Raman spectroscopy; 2. the molecular weight (M w) of the powder of U, K, T, and L materials and of K polymerized specimens (control; MW; and WB) by GPC; 3. the effect of MW and WB on the glass transition temperature (Tg) of the reline resins (Duraliner II-D, K, New Truliner-N, U and T) and the heat-polymerized resin (LS and LL) by DSC; 4. the effect of WB on the leaching of residual compounds (isobutyl methacrylate- IBMA, 1,6-hexanediol dimethacrylate-1,6-HDMA, and DBNP-dibutyl-nphthalate) from the reline resins (K, N, U, and T) in artificial saliva by HPLC; 5. the effect of WB on the leaching of degradation products (methacrylic acid-MA and benzoic acid-BA) from the reline resins K, N, U, and T in artificial saliva by HPLC. Control group specimens were left untreated. DC (%) data were analyzed using Kruskal-Wallis test (_=.05). Tg (ºC) data were analyzed using ANOVA/Tukey's test (_=.05). The results (æg/mL) of residual monomer and plasticizer leachability were submitted to Wilcoxon or Mann-Whitney tests (_=.05). The results (æg/mL) of degradation products leachability were submitted to Wilcoxon, Mann-Whitney or Kruskal-Wallis tests (_=.05). For DC control specimens, there were no significant differences between U and LL and among LL, K, and T. LS specimens had the highest DC. Only material K exhibited an increased DC after WB. All powders had M w from 4.0x105 to 6.5x105 and narrow M w distributions (2.1 to 3.6). Polymerization and post-polymerization produced K specimens with M w values similar to that of K powder...(Complete abstract, click electronic address below). / Orientador: Ana Lucia Machado / Coorientador: Quezia Bezerra Cass / Banca: Carlos Eduardo Vergani / Banca: Carlos Alberto dos Santos Cruz / Banca: Marcelo Ferraz Mesquita / Banca: Regina Vincenzi Oliveira / Doutor