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京都大学 / 新制・課程博士 / 博士(工学) / 甲第24643号 / 工博第5149号 / 新制||工||1983(附属図書館) / 京都大学大学院工学研究科化学工学専攻 / (主査)教授 河瀬 元明, 教授 大嶋 正裕, 教授 佐野 紀彰 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

A exploração de processos viáveis para a conversão da biomassa lignocelulósica em combustíveis limpos e produtos químicos de alto valor agregado, para complementar ou substituir produtos derivados de fontes não renováveis, é crucial para um desenvolvimento sustentável. A valorização e modificação dos componentes lignocelulósicos, torna-se imprescindível para viabilizar o sistema de biorrefinaria. A lignina, macromolécula aromática dominante na natureza, é um destes componentes que, devido a sua estrutura e composição, oferece rotas únicas para a produção de vários químicos de valor agregado. Este trabalho tem como objetivo avaliar o efeito de reações de oxidação em ligninas de bagaço e de palha de cana-de-açúcar, e de casca de café, na obtenção de compostos aromáticos de baixa massa molar, em especial a vanilina, e adicionalmente, verificar a aplicabilidade da lignina oxidada residual na obtenção de matrizes para liberação controlada de herbicida, buscando alternativas para agregar valor à lignina proveniente de resíduos agroindustriais e contribuir com a viabilização de biorrefinarias. Para isso, os materiais lignocelulósicos foram pré-tratados com ácido diluído e submetidos a deslignificação alcalina para obtenção da lignina. As frações obtidas durante cada etapa foram avaliadas quanto a composição química e Espectrometria no Infravermelho (FTIR), e as ligninas obtidas, foram ainda avaliadas por Espectrometria no Ultravioleta (UV) e por Ressonância Magnética Nuclear (1H RMN, 13C RMN e 2D RMN). As ligninas obtidas foram oxidadas em diferentes condições: oxidação enzimática utilizando lacase, em meio ácido e em meio alcalino com H2O2 e oxidação úmida em meio aquoso e alcalino utilizando H2O2. A fração líquida obtida foi analisada por Cromatografia Líquida de Alta Eficiência (CLAE) para identificar e quantificar os aldeídos aromáticos e outros compostos de degradação, enquanto a fração sólida, constituída pela lignina residual oxidada, foi avaliada por FTIR e UV. As ligninas oxidadas provenientes das condições que resultaram em um maior rendimento de vanilina, foram aplicadas na formulação de matrizes para liberação controlada de ametrina. Os resultados mostraram que a lignina de bagaço e de palha de cana não oxidadas são compostas principalmente por unidades siringil e guaiacil, respectivamente, e predominância de ligações ?-O-4, enquanto a lignina de casca de café foi composta principalmente por unidades hidroxil e predominância de ligações C-C, indicando uma estrutura mais condensada. Das oxidações avaliadas, a oxidação em meio alcalino (NaOH 10%) utilizando H2O2 9,1% gerou um maior rendimento de vanilina quando utilizada lignina de bagaço (8,13 mg/g lignina) e de casca de café (1,15 mg/g lignina), e H2O2 6,1% quando utilizada lignina de palha (6,48 mg/g lignina). A aplicação das ligninas oxidadas permitiu a obtenção de matrizes capazes de liberar o herbicida ametrina com diferentes cinéticas, dependendo das propriedades e das proporções das ligninas empregadas. / The exploration of feasible paths for the conversion of the lignocellulosic biomass into clean fuels and high value chemicals, to complement or replace products derived from non-renewable sources, is crucial for a sustainable development. The efficient utilization of the lignocellulosic components is of fundamental importance for the economic viability of biorefineries. Lignin, nature\'s dominant aromatic polymer, is a major component of the biomass that, due to its structuture and chemical composition, is a unique feedstock for producing high-value chemicals. The aim of this study is to seek for alternatives for adding value to lignin from agro-industrial waste in order to contribute to the vialbility of biorefineries. To achieve this, we evaluated the effect of oxidation reactions in sugarcane bagasse and straw lignin, and coffee husk, for obtaining aromatic compounds of low molecular weight, especially vanillin. In addition, the applicability of the residual oxidized lignin for obtaining matrices for the controlled release of herbicides was also examined in this work. For this purpose, the lignocellulosic materials were pretreated with dilute acid and subjected to alkaline delignification to achieve separation of the lignin. The fractions obtained at each stage were analyzed for chemical composition and with Infrared Spectroscopy (FTIR). The lignins were also analyzed using UV-vis Spectroscopy (UV) and Nuclear Magnetic Resonance (1H NMR, 13C NMR and HSQC). The lignins obtained were subjected to oxidation using different physiochemical conditions - enzymatic oxidation with laccase, oxidation in acidic and alkaline medium with H2O2 and wet oxidation in aqueous and alkaline medium using H2O2.The obtained liquid fraction was analyzed by High Performance Liquid Chromatography (HPLC) to identify and quantify the aromatic aldehydes and other compounds of lignin degradation, while the solid fraction, comprising the oxidized residual lignin, was analyzed by FTIR and UV. The oxidized lignins derived from the conditions that have resulted in a maximun yield of vanillin, were applied in the formulation of controlled release matrices of ametryne. Results for non oxidized lignin showed bagasse and straw lignin being composed mainly of syringyl and guaiacil units, respectively, linked predominantly by ?-O-4 bonds, while coffee husk lignin was mainly composed of hydroxyl units linked by C-C bonds predominantly, indicating a more condensed structure. Of all the oxidation reactions, the oxidation in alkaline medium (NaOH 10%) using H2O2 9.1% showed the highest yield of vanillin with bagasse lignin (8.13 mg/g lignin) and coffee husk lignin (1.15 mg/g lignin), and H2O2 6.1% with straw lignin (6.48 mg/g lignin). The application of oxidized lignins as matrices resulted in the release of the herbicide ametryne with different kinetics, depending on the proportions and properties of the lignins applied.

A exploração de processos viáveis para a conversão da biomassa lignocelulósica em combustíveis limpos e produtos químicos de alto valor agregado, para complementar ou substituir produtos derivados de fontes não renováveis, é crucial para um desenvolvimento sustentável. A valorização e modificação dos componentes lignocelulósicos, torna-se imprescindível para viabilizar o sistema de biorrefinaria. A lignina, macromolécula aromática dominante na natureza, é um destes componentes que, devido a sua estrutura e composição, oferece rotas únicas para a produção de vários químicos de valor agregado. Este trabalho tem como objetivo avaliar o efeito de reações de oxidação em ligninas de bagaço e de palha de cana-de-açúcar, e de casca de café, na obtenção de compostos aromáticos de baixa massa molar, em especial a vanilina, e adicionalmente, verificar a aplicabilidade da lignina oxidada residual na obtenção de matrizes para liberação controlada de herbicida, buscando alternativas para agregar valor à lignina proveniente de resíduos agroindustriais e contribuir com a viabilização de biorrefinarias. Para isso, os materiais lignocelulósicos foram pré-tratados com ácido diluído e submetidos a deslignificação alcalina para obtenção da lignina. As frações obtidas durante cada etapa foram avaliadas quanto a composição química e Espectrometria no Infravermelho (FTIR), e as ligninas obtidas, foram ainda avaliadas por Espectrometria no Ultravioleta (UV) e por Ressonância Magnética Nuclear (1H RMN, 13C RMN e 2D RMN). As ligninas obtidas foram oxidadas em diferentes condições: oxidação enzimática utilizando lacase, em meio ácido e em meio alcalino com H2O2 e oxidação úmida em meio aquoso e alcalino utilizando H2O2. A fração líquida obtida foi analisada por Cromatografia Líquida de Alta Eficiência (CLAE) para identificar e quantificar os aldeídos aromáticos e outros compostos de degradação, enquanto a fração sólida, constituída pela lignina residual oxidada, foi avaliada por FTIR e UV. As ligninas oxidadas provenientes das condições que resultaram em um maior rendimento de vanilina, foram aplicadas na formulação de matrizes para liberação controlada de ametrina. Os resultados mostraram que a lignina de bagaço e de palha de cana não oxidadas são compostas principalmente por unidades siringil e guaiacil, respectivamente, e predominância de ligações ?-O-4, enquanto a lignina de casca de café foi composta principalmente por unidades hidroxil e predominância de ligações C-C, indicando uma estrutura mais condensada. Das oxidações avaliadas, a oxidação em meio alcalino (NaOH 10%) utilizando H2O2 9,1% gerou um maior rendimento de vanilina quando utilizada lignina de bagaço (8,13 mg/g lignina) e de casca de café (1,15 mg/g lignina), e H2O2 6,1% quando utilizada lignina de palha (6,48 mg/g lignina). A aplicação das ligninas oxidadas permitiu a obtenção de matrizes capazes de liberar o herbicida ametrina com diferentes cinéticas, dependendo das propriedades e das proporções das ligninas empregadas. / The exploration of feasible paths for the conversion of the lignocellulosic biomass into clean fuels and high value chemicals, to complement or replace products derived from non-renewable sources, is crucial for a sustainable development. The efficient utilization of the lignocellulosic components is of fundamental importance for the economic viability of biorefineries. Lignin, nature\'s dominant aromatic polymer, is a major component of the biomass that, due to its structuture and chemical composition, is a unique feedstock for producing high-value chemicals. The aim of this study is to seek for alternatives for adding value to lignin from agro-industrial waste in order to contribute to the vialbility of biorefineries. To achieve this, we evaluated the effect of oxidation reactions in sugarcane bagasse and straw lignin, and coffee husk, for obtaining aromatic compounds of low molecular weight, especially vanillin. In addition, the applicability of the residual oxidized lignin for obtaining matrices for the controlled release of herbicides was also examined in this work. For this purpose, the lignocellulosic materials were pretreated with dilute acid and subjected to alkaline delignification to achieve separation of the lignin. The fractions obtained at each stage were analyzed for chemical composition and with Infrared Spectroscopy (FTIR). The lignins were also analyzed using UV-vis Spectroscopy (UV) and Nuclear Magnetic Resonance (1H NMR, 13C NMR and HSQC). The lignins obtained were subjected to oxidation using different physiochemical conditions - enzymatic oxidation with laccase, oxidation in acidic and alkaline medium with H2O2 and wet oxidation in aqueous and alkaline medium using H2O2.The obtained liquid fraction was analyzed by High Performance Liquid Chromatography (HPLC) to identify and quantify the aromatic aldehydes and other compounds of lignin degradation, while the solid fraction, comprising the oxidized residual lignin, was analyzed by FTIR and UV. The oxidized lignins derived from the conditions that have resulted in a maximun yield of vanillin, were applied in the formulation of controlled release matrices of ametryne. Results for non oxidized lignin showed bagasse and straw lignin being composed mainly of syringyl and guaiacil units, respectively, linked predominantly by ?-O-4 bonds, while coffee husk lignin was mainly composed of hydroxyl units linked by C-C bonds predominantly, indicating a more condensed structure. Of all the oxidation reactions, the oxidation in alkaline medium (NaOH 10%) using H2O2 9.1% showed the highest yield of vanillin with bagasse lignin (8.13 mg/g lignin) and coffee husk lignin (1.15 mg/g lignin), and H2O2 6.1% with straw lignin (6.48 mg/g lignin). The application of oxidized lignins as matrices resulted in the release of the herbicide ametryne with different kinetics, depending on the proportions and properties of the lignins applied.

Aquatic systems worldwide receive large amounts of organic carbon from terrestrial sources. This ‘allochthonous’ organic carbon (AlloOC) affects critical physical and chemical properties of freshwater ecosystems, with consequences for food web structures and exchange of greenhouse gases with the atmosphere. In the boreal region, loadings of AlloOC are particularly high due to leaching from huge organic deposits in boreal forest, mire and tundra soils. A main process of AlloOC turnover in aquatic systems is its use by heterotrophic bacteria. Applying a bioassay approach, I measured the respiration and growth (production) of bacteria in northern Sweden, in streams and lakes almost totally dominated by AlloOC. The objective was to elucidate how variations in AlloOC source, age, composition and concentration impact on its use by aquatic bacteria, and how AlloOC properties, in turn, are regulated by landscape composition and by hydrology. The bacterial respiration (30-309 µg C L-1 d-1) was roughly proportional to the concentration of AlloOC (7-47 mg C L-1), but not significantly related to AlloOC source or character. Bacterial production (4-94 µg C L-1 d-1), on the other hand, was coupled to the AlloOC character, rather than concentration. A strong coupling to AlloOC character was also found for bacterial growth efficiency (0.06-0.51), i.e. production per unit of assimilated carbon. Bacterial production and growth efficiency increased with rising concentrations of low molecular weight AlloOC (carboxylic acids, free amino acids and simple carbohydrates). While the total AlloOC concentrations generally were the highest in mire-dominated catchments, low molecular weight AlloOC concentrations were much higher in forested catchments, compared to mire-dominated. These patterns were reflected in a strong landscape control of aquatic bacterial metabolism. Moreover, high flow episodes increased the export of organic carbon from forests, in relation to the export from mires, stimulating the bacterial production and growth efficiency in streams with mixed (forest and mire) catchments. The potential of AlloOC to support efficient bacterial growth decreased on time-scales of weeks to months, as the AlloOC was aged in laboratory or lake in situ conditions. To conclude, landscape, hydrology and conditions which determine AlloOC age have large influence on bacterial metabolism in boreal aquatic systems. Considering the role of bacteria in heterotrophic food chains, these factors can have spin-off effects on the structure and function of boreal aquatic ecosystems.

The primary objective of this research is to generate reinforcing domains in situ during the processing of polymers by using phase separation techniques. Low molecular weight compounds were mixed with polymers where the process viscosity is reduced at process temperatures and mechanical properties are improved once the material system is cooled or reacted. Thermally induced phase separation and thermotropic phase transformation of low molar mass compounds were used in isotactic polypropylene (iPP) and poly(ether ether ketone) (PEEK) resins. Reaction induced phase separation was utilized in thermosets to generate anisotropic reinforcements. A new strategy to increase fracture toughness of materials was introduced. Simultaneously, enhancement in stiffness and reduction in process viscosity were also attained. Materials with improved rheological and mechanical properties were prepared by using thermotropic phase transformations of metal soaps in polymers (calcium stearate/iPP). Morphology and thermal properties were studied using WAXS, DSC and SEM. Mechanical and rheological investigation showed significant reduction in process viscosity and substantial improvement in fracture toughness were attained. Effects of molecular architecture of metal soaps were investigated in PEEK (calcium stearate/PEEK and sodium stearate/PEEK). The selected compounds reduced the process viscosity due to the high temperature co-continuous morphology of metal soaps. Unlike the iPP system that incorporates spherical particles, interaction between PEEK and metal soaps resulted in two discrete and co-continuous phases of PEEK and the metal stearates. DMA and melt rheology exhibited that sodium stearate/PEEK composites are stiffer. Effective moduli of secondary metal stearate phase were calculated using different composite theories, which suggested bicontinuous morphology to the metal soaps in PEEK. Use of low molecular weight crystallizable solvents was investigated in reactive systems. Formation of anisotropic reinforcements was evaluated using dimethyl sulfone (DMS) as the crystallizable diluent and diglycidyl ether of bisphenol-A (DGEBA)/m-phenylene diamine (mPDA) material system as the epoxy thermoset. Miscible blends of DMS and DGEBA/mPDA form homogenous mixtures that undergo polymerization induced phase separation, once the DGEBA oligomers react with mPDA. The effect of the competition between the crystallization and phase separation of DMS resulted in nano-wires to micro-scale fiber-like crystals that were generated by adjusting the reaction temperature and DMS concentration.

Corantes reativos têxteis podem ser degradados por basidiomicetos, por meio de enzimas oxidativas e hidrolíticas, e compostos de baixa massa molar. Foi avaliada a descoloração de CI Reactive Blue 222 por Peniophora cinerea, Pleurotus ostreatus e Trametes villosa, selecionando condições ótimas para o processo e diferentes vias metabólicas foram observadas. A degradação foi confirmada por cromatografia de camada delgada. Foi sugerido que lacases de P. ostreatus oxidam o grupo cromóforo azo, ligado ao fenol, nas primeiras 24 horas, conjuntamente hidroxilização não enzimática. Lacases de P. cinerea oxidam Mn+2 e quinona, possibilitando a via de Fenton e hidroxilizando assim a molécula do corante, paulatinamente, a partir das ligações mais vulneráveis. T. villosa faz uso prioritariamente da via de Fenton, hidroxilizando gradativamente a molécula do corante. Dessa forma, embora a maioria de estudos associem a produção enzimática à descoloração, a participação dos compostos de baixa massa molar não pode ser negligenciada. / Reactive textile dyes can be degraded by basidiomycetes, by means of hydrolytic and oxidative enzymes, and low molecular weight compounds. Was evaluated the CI Reactive Blue 222 decolorization by Peniophora cinerea, Pleurotus ostreatus, and Trametes villosa, selecting optimal conditions for the process and different metabolic pathways were observed. The degradation was confirmed by thin layer chromatography. It was suggested that P. ostreatus laccases oxidize azo chromophore group attached to the phenol, within 24 hours, together nonenzymatic hydroxylizating. P. cinerea laccases oxidize Mn+2 and quinone, enabling via Fenton and so hidroxylizing the dye molecule, gradually, from the most vulnerable links. T. villosa uses primarily via Fenton, gradually hidroxylizing the dye molecule. Thus, although most studies have linked enzyme production with the decolorization, the share of low molecular weight compounds can not be neglected.

Corantes reativos têxteis podem ser degradados por basidiomicetos, por meio de enzimas oxidativas e hidrolíticas, e compostos de baixa massa molar. Foi avaliada a descoloração de CI Reactive Blue 222 por Peniophora cinerea, Pleurotus ostreatus e Trametes villosa, selecionando condições ótimas para o processo e diferentes vias metabólicas foram observadas. A degradação foi confirmada por cromatografia de camada delgada. Foi sugerido que lacases de P. ostreatus oxidam o grupo cromóforo azo, ligado ao fenol, nas primeiras 24 horas, conjuntamente hidroxilização não enzimática. Lacases de P. cinerea oxidam Mn+2 e quinona, possibilitando a via de Fenton e hidroxilizando assim a molécula do corante, paulatinamente, a partir das ligações mais vulneráveis. T. villosa faz uso prioritariamente da via de Fenton, hidroxilizando gradativamente a molécula do corante. Dessa forma, embora a maioria de estudos associem a produção enzimática à descoloração, a participação dos compostos de baixa massa molar não pode ser negligenciada. / Reactive textile dyes can be degraded by basidiomycetes, by means of hydrolytic and oxidative enzymes, and low molecular weight compounds. Was evaluated the CI Reactive Blue 222 decolorization by Peniophora cinerea, Pleurotus ostreatus, and Trametes villosa, selecting optimal conditions for the process and different metabolic pathways were observed. The degradation was confirmed by thin layer chromatography. It was suggested that P. ostreatus laccases oxidize azo chromophore group attached to the phenol, within 24 hours, together nonenzymatic hydroxylizating. P. cinerea laccases oxidize Mn+2 and quinone, enabling via Fenton and so hidroxylizing the dye molecule, gradually, from the most vulnerable links. T. villosa uses primarily via Fenton, gradually hidroxylizing the dye molecule. Thus, although most studies have linked enzyme production with the decolorization, the share of low molecular weight compounds can not be neglected.

L’objectif de ce travail de thèse était d’étudier l’effet de la stérilisation par électrons accélérés sur les copolymères d’oléfines cycliques (COC), utilisés comme conditionnement de produits pharmaceutiques, ainsi que son impact sur les interactions avec des formulations pharmaceutiques. Grâce à la méthodologie analytique adoptée qui a fait appel à différentes techniques de caractérisation, telles que la chromatographie d’exclusion stérique, la chromatographie liquide haute performance à polarité de phases inversée, la spectroscopie infra rouge à transformée de Fourier, la microscopie à force atomique et les mesures d’angles de contact, nous avons pu mettre en évidence différents types de modifications dans le volume et sur la surface du matériau après stérilisation ainsi qu’après vieillissement. La modification principale du dans la masse du matériau, observée à la dose réglementaire de stérilisation (25 kGy), est la scission des chaînes du polymère, qui s’accompagne de la création de composés de faible masse molaire, donc de migrants potentiels risquant d’influencer la sécurité d’emploi des COC. En effet, certains de ces composés ont été retrouvés avec une concentration relativement importante dans les solutions de mise en contact avec les COC stérilisés, et notamment en solution aqueuse. Toutefois, l’étude préliminaire de toxicité a montré l’absence de cytotoxicité des extractibles obtenus à la dose de la stérilisation.Les modifications relatives à la surface des COC radio-stérilisés sont, quant à elles, de deux natures : physique avec une augmentation de la rugosité de surface et chimique avec la formation de produits d’oxydation polaires ; ces deux types de modifications conduisent à l’augmentation de la mouillabilité de surface. Cependant dans certains cas, notamment après vieillissement, ces modifications sont relativement faibles, même à des doses supérieures à celle préconisée pour la stérilisation, ce qui peut être corrélé à l’absence de l’effet de l’irradiation sur le comportement des COC vis-à-vis des solutions médicamenteuses. En effet, aucune variation de la sorption des principes actifs choisis n’a été montrée entre les COC irradiés et non irradiés vieillis. / The aim of this work was to study the effect of electron beam radio-sterilization on cyclo olefins copolymers (COC) used as pharmaceutical storage materials, as well as to investigate its impact on the interaction with pharmaceuticals formulations. Due to the analytical methodology used which dealt with different techniques of characterization such as size exclusion chromatography, reversed phase high performance liquid chromatography, Fourier transformed infrared spectroscopy, atomic force microscopy and contact angle measurements, we have been able to put into evidence different kinds of modifications both in the bulk and on the surface of the sterilized material and also after ageing.The principal modification of material’s bulk, observed at the recommended dose for sterilization (25 kGy), was polymer chains scissions, accompanied with creation of low molecular weight compounds, that are potentials migrants that risk to affect the safe use of COC. Indeed, some of these compounds have been found with a relatively important concentration in the solutions where sterilized COC was stored, especially in aqueous solutions. However, the preliminary study of toxicity has shown the absence of cytotoxicity of the extractables obtained at the sterilization dose.Surface modifications of radio-sterilized COC are of two types: a physical one, with an increase of the surface’s roughness and a chemical one with the formation of polar oxidation products; these two modifications result in an increase of surface’s wettability that may be important. However, in some cases such as for aged samples, these modifications are relatively weak even at doses higher than the one recommended for sterilization, which can explain the absence of the effect of radiation on the behavior of COC towards drug solutions. Indeed, no variation of drug sorption has been observed between aged COC irradiated and none irradiated.