Thesis (Doctor of Engineering in Chemical Engineering)--Cape Peninsula University of Technology, 2018. / Lignocellulosic biomass (agro-waste) has been recommended as the most promising feedstock for the production of bioalcohols, in the biofuel industry. Furthermore, agro-waste is well-known as the most abundant organic matter in the agricultural and forestry product processing industry. However, the challenge with utilizing agro-waste as a feedstock is its highly recalcitrant structure, which limits hydrolysis to convert the holocelluloses into fermentable sugars. Conventional pre-treatment methods such as dilute acid, alkaline, thermal, hot water and enzymatic, have been used in previous studies. The challenge with these conventional methods is the generation of residual toxicants during the pretreatment process, which inhibits a high bioalcohol yield, by reducing the microbial populations’ (fermenter) ability to be metabolically proficient during fermentation. Numerous studies have been developed to improve the engineered strains, which have shown to have an ability to reduce the inhibition and toxicity of the bioalcohols produced or by-products produced during pre-treatment, while enhancing the bioalcohol production. In the present study (chapter 5), evaluation of common conventional methods for the pretreatment of the mixed agro-waste, i.e. (˃45µm to <100µm) constituted by Citrus sinensis, Malus domestica peels, corn cobs from Zea mays and Quercus robur (oak) yard waste without a pre-rinsing step at a ratio of 1:1 at 25% (w/w) for each waste material, was undertaken, focusing on hot water pre treatment followed by dilute acid (H2SO4) pre-treatment. To further pretreat the mixed agro-waste residue, cellulases were used to further hydrolyse the pre-treated agro-waste in a single pot (batch) multi-reaction process. The TRS concentration of 0.12, 1.43 and 3.22 g/L was achieved with hot water, dilute acid and cellulases hydrolysis as sequential pretreatment steps, respectively, in a single pot multi-reaction system. Furthermore, a commercial strain was used to ascertain low (C1 to C3) and high carbon content (C4+) bioalcohol production under aerobic conditions. Multiple bioproducts were obtained within 48 to 72 h, including bioethanol and 1-Butanol, 3-methyl, which were major products for this study. However, undesirable bio-compounds such as phenolics, were detected post fermentation. Since multiple process units characterised by chemical usage and high energy intensivity have been utilized to overcome delignification and cellulolysis, a sustainable, environmental benign pretreatment process was proposed using N. mirabilis “monkey cup” fluids (extracts) to also reduce fermenter inhibitors from the delignification of mixed agrowaste; a process with minimal thermo physical chemical inputs for which a single pot multi-reaction system strategy was used. Nepenthes mirabilis extracts shown to have ligninolytic, cellulolytic and xylanolytic activities, were used as an enzyme cocktail to pretreat mixed agro-waste, subsequent to the furtherance of TRS production from the agro-waste, by further using cellulase for further hydrolysis. N. mirabilis pod extracts were determined to contained carboxylesterases (529.41±30.50 U/L), β-glucosidases (251.94±11.48 U/L) and xylanases (36.09±18.04 U/L), constituting an enzymatic cocktail with a significant potential for the reduction in total residual phenolic compounds (TRPCs). Furthermore, the results indicated that maximum concentration of TRS obtainable was 310±5.19 mg/L within 168 h, while the TRPCs were reduced from 6.25±0.18 to 4.26 ±0.09 mg/L, which was lower than that observed when conventional methods were used. Overall N. mirabilis extracts were demonstrated to have an ability to support biocatalytic processes for the conversion of agro-waste to produce fermentable TRS in a single unit facilitating multiple reactions with minimised interference with cellulase hydrolysis. Therefore, the digestive enzymes in N. mirabilis pods can be used in an integrated system for a second generation biorefinery.

Nanotubos de carbono (NTC) apresentam superlativas propriedades físico-químicas. Por essa razão, têm sido tema de diversas pesquisas, teóricas e experimentais, para sua aplicação em compósitos que transmitam a outros materiais de interesse, as suas propriedades intrínsecas superiores. Materiais híbridos apresentam propriedades que são diferentes das de seus componentes individuais, sendo resultado das interações e das quantidades de seus componentes. O presente trabalho teve como objetivo a investigação das propriedades híbridas que podem surgir quando nanotubos de carbono são crescidos verticalmente sobre diferentes tipos de substratos micrométricos. Particularmente, foram investigados o comportamento dos compósitos micro-nanoestruturados desenvolvidos, frente à redução de metais e ao reforço mecânico de um polímero termoplástico (PVC). Para conduzir o presente estudo, dois tipos de NTC foram crescidos sobre substratos de carvão ativado, grafita e dióxido de titânio, pelo método da deposição química de vapor (CVD). Estes substratos são, tradicionalmente, usados como agentes de redução, adsorventes e cargas para reforço mecânico. As principais técnicas de investigação do presente trabalho foram a microscopia eletrônica de varredura (MEV), espectroscopia por energia dispersiva de raios-X (EDS), acoplada ao MEV, difração de raios-X e também, no caso dos compósitos de PVC, ensaios de tração mecânica em um texturômetro. Os resultados demonstram que existem combinações entre o tipo de NTC e o suporte microestruturado, que podem resultar em propriedades que não são observadas nos constituintes dos compósitos estudados, quando estes estão na forma isolada. Portanto, o crescimento de nanoestruturas sobre os substratos pode gerar propriedades híbridas como: a redução e adsorção nos NTC, de certos íons metálicos de Ag e Cu, sem o uso de agente redutor ou aplicação de potencial externo. E também, pode dar origem a aditivos de reforço mecânico para PVC que podem levar a consideráveis aumentos no módulo de elasticidade e limite de resistência à tração, em relação ao PVC isoladamente (aumentos de 5.068,21 % e 4.110,74%, respectivamente) / Carbon nanotubes (CNT) have been the subject of several theoretical and experimental researches due to their superlative intrinsic physicochemical properties, especially in the field of composites. However, there are some problems concerned to the successful transmission of these superior properties to the materials of interest. Hybrid materials have properties that are different from those of their individual components, which results from the interactions and also the quantities of the components. This work aimed at investigating the hybrid properties that can arise when carbon nanostructures are vertically grown on different types of microstructured substrates. Particularly, the behavior of the micro-nanostructured composites has been investigated as a function of the chemical reduction of metal ions and the mechanical reinforcement of a thermoplastic polymer (PVC). In order to conduct this study, two types of CNT were grown on the surfaces of charcoal, graphite and titanium dioxide through the chemical vapor deposition (CVD) method. These substrates are traditionally used as reducing agents, adsorbents and reinforcing fillers. The PVC composite samples were characterized, mainly, by mechanical traction tests in a texturometer, and the other samples were characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDS), and X-ray diffraction (XRD). The results demonstrated that there are combinations between specific types of CNT and microstructured supports that can lead to properties not observed in the isolated constituents of the composite. Therefore, the growth of nanostructures on substrates can generate hybrid properties, such as the reduction of Ag and Cu ions and their direct adsorption on CNT without the need of a reducing agent or application of an external potential, as in the case of some charcoals. Additionally, some of these composites can form mechanical fillers for PVC, which can lead to substantial increases in the elasticity modulus and tensile strength, (5.068,21% and 4.110,74%, respectively), when compared to the isolated PVC.

O objetivo deste trabalho foi avaliar a interferência da sulfetogênese sobre a produção de metano em reator anaeróbio de leito fixo ordenado tratando água residuária orgânica contendo sulfato. A escolha dessa configuração de reator foi devida à possibilidade de manutenção de uma área transversal de escoamento na zona reacional, o que minimiza diversos problemas oriundos da colmatação do leito por acúmulo de polímeros extracelulares e sólidos suspensos nos interstícios do material suporte. Foram utilizados dois sistemas em paralelo com as mesmas características operacionais e alimentados com água residuária sintética simulando alguns componentes da fração solúvel da vinhaça, e matéria orgânica constituída por uma mistura de sacarose, etanol e fenol. Um dos reatores recebeu adição de sulfato apenas como fonte de enxofre requerido pela digestão anaeróbia e o outro recebeu dosagem de sulfato para relações DQO/Sulfato de 3 a 5. O estudo se estendeu por 7 fases operacionais distintas. A concentração afluente de matéria orgânica variou de 800 para 1000, 2000 e 4000 mg.L-1. O tempo de detenção hidráulica (TDH) foi de 24 h. Na última fase operacional (com carga orgânica aplicada de 4 g.L-1.dia-1) as eficiências de remoção de matéria orgânica chegaram a cerca de 97% no reator metanogênico e de 96% no reator sulfetogênico. Este último também obteve eficiências de remoção de sulfato da ordem de 97% nessa fase (com relação DQO/Sulfato de 3 e concentração afluente de sulfato de 1300 mg.L-1), chegando ao máximo de 99% de remoção em alguns dias de operação. No sistema sulfetogênico a relação DQO/Sulfato que proporcionou maiores eficiências de remoção combinada de matéria orgânica e sulfato, com maior geração de alcalinidade, foi de 3 gDQO/gSO42-. Os reatores metanogênico e sulfetogênico apresentaram rendimentos de metano próximos ao longo do tempo, tendo o sistema sulfetogênico apresentado rendimento de metano superior ao alcançado pelo sistema metanogênico em alguns dias da operação. Na última fase os rendimentos médios de metano obtidos foram, nas CNTP, da ordem de 320 mLCH4/gDQOremovida no reator sulfetogênico, e da ordem de 315 mLCH4/gDQOremovida no reator metanogênico. Esses resultados não indicaram inibição significativa da atividade metanogênica sob as condições impostas no sistema sulfetogênico, viabilizando a recuperação de energia pelo aproveitamento do metano. / The aim of this study was to evaluate the interference of sulphidogenesis on methane production in structured bed anaerobic reactor treating organic wastewater containing sulphate. Choosing this setting reactor was due to the possibility of maintaining a crosssectional area of flow in the reaction zone, which minimizes several problems caused by the clogging of the bed by accumulation of extracellular polymers and suspended solid in the interstices of support material. Two parallel systems were used with the same operational features and fed with synthetic wastewater simulating some compounds of the soluble fraction of vinasse, and organic matter constituted by a mixture of sucrose, ethanol and phenol. One reactor received sulphate just as a source of sulfur required for anaerobic digestion and another one received sulphate dosage for COD/Sulphate ratios from 3 to 5. Seven distinct operational phases were tested. The influent concentration of organic matter ranged from 800 to 1000, 2000 and 4000 mg.L-1. The hydraulic retention time (HRT) was 24 h. In the last step (with organic loading rate of 4 g.L-1.day-1) the efficiencies of organic matter removal were around 97% in the methanogenic reactor and 96% in sulfidogenic reactor. The last one also achieved efficiencies of sulphate removal close to 97% in this phase (COD/Sulphate ratio of 3 and influent sulphate concentration of 1300 mg.L-1), reaching a maximum removal of 99% in some operational days. The COD/Sulphate ratio in sulfidogenic system that showed higher efficiencies of combined removal of organic matter and sulphate, with higher generation of alkalinity, was 3 gCOD/gSO42-. The methanogenic and sulfidogenic reactors showed similar values of methane yield, having the sulfidogenic system presented higher methane yield than achieved by methanogenic system at some operational days. In the last phase the average yields of methane obtained, at NTP, were around 320 mLCH4/gCODremoved in the sulfidogenic reactor, and around 315 mLCH4/gCODremoved in the methanogenic reactor. These results indicated no significant inhibition of methanogenic activity under the conditions imposed in sulfidogenic system, enabling energy recovery by use of produced methane.

A princípio, foram realizados ensaios de enriquecimento em reatores em batelada, sob agitação, para avaliar a melhor condição nutricional, meio Beller ou meio Zinder, para crescimento microbiano e remoção de sulfato. Posteriormente, esta melhor condição nutricional foi usada para crescimento microbiano e remoção de etanol, tolueno e benzeno em ensaios contínuos em dois reatores anaeróbios horizontais de leito fixo (RAHLF), sob condições de redução de sulfato. Os sistemas foram inoculados com lodo de reator anaeróbio de fluxo ascendente e manta de lodo tratando águas residuárias provenientes de abatedouro de aves. Os RAHLF consistiram de biomassa imobilizada em espumas de poliuretano submetidas a concentrações de 91 e 550 mg/l de sulfato ferroso e sulfato de sódio, respectivamente, para promoção de ambiente sulfetogênico. Tolueno e benzeno foram adicionados, separadamente nos reatores, em concentrações iniciais de 2,0 mg/l, seguidas de aumentos que variaram até as concentrações finais de 9 e 10 mg/l, para tolueno e benzeno, respectivamente. O etanol foi adicionado em ambos reatores a concentração inicial de 170 mg/l, seguido de aumento de até 960 mg/l. Os reatores foram operados a 30 (± 2) ºC com tempo de detenção hidráulica de 12 h. A eficiência na remoção da matéria orgânica nos dois reatores foi próxima a 90% com taxa máxima de degradação de tolueno de 0,06 mg tolueno/mg ssv.d, e 0,07 mg benzeno/mg ssv.d, para benzeno. A redução de sulfato foi de 99,9% em todas as condições nutricionais nos dois reatores. A caracterização microscópica do biofilme revelou diversas morfologias e o perfil de DGGE mostrou variação nas populações de BRS e de representantes do Domínio Bacteria em geral, o que foi associado com as crescentes concentrações de tolueno e benzeno nos meios de alimentação. Finalmente, o presente trabalho demonstrou que unidades compactas de RAHLF, sob condições sulfetogênicas, oferecem alternativa para a biorremediação in situ de compostos aromáticos. / Previously, enrichment assays in batch reactors were used to evaluation of best nutritional condition, Beller or Zinder medium, to microorganism growth and sulfate removal. Further, the chosen nutritional condition was used in two horizontal-flow anaerobic immobilized biomass (HAIB) reactors under sulphate-reducing condition, which were exposed to different amounts of ethanol, toluene and benzene. The systems were inoculated with sludge taken from up-flow anaerobic sludge blanket (UASB) reactors treating refuses from a poultry slaughterhouse. The HAIB reactors comprised of an immobilized biomass on polyurethane foam and ferrous and sodium sulphate solutions were used (91 and 550 mg/L, respectively), to promote a sulphate-reducing environment. Toluene and benzene were added at an initial concentration of 2.0 mg/L followed by an increased range of different amendments. Ethanol was added at an initial concentration of 170 mg/L followed by an increased range of 960 mg/L. The reactors were operated at 30 (± 2) °C with hydraulic detention time of 12 h. Organic matter removal efficiency of 90%, in both systems, with a maximum toluene degradation rate of 0.06 mg toluene/mg vss.d and with a maximum benzene degradation rate of 0.07 mg benzene/mg vss.d. Sulfate reduction was dose to 99.9% for all-nutritional amendments in both systems. Biofilm microscopic characterization revealed a diversity of microbial morphologies and DGGE-profiling showed a variation of bacterial and sulphate reducing bacteria (SRB) populations, which were, significantly, associated with toluene and benzene amendments. Thus, this work demonstrates that compact units of HAIB reactors, under sulphate reducing conditions, are a potential alternative for in situ aromatic compounds bioremediation.

O presente trabalho aborda os fundamentos do princípio da ordem econômica da redução das desigualdades regionais e sociais previsto no artigo 170, VII, e, paralelamente, o artigo 3º, III, ambos da Constituição da República Federativa do Brasil de 1988 sob o viés do Direito Econômico. Inicialmente são expostas considerações propedêuticas acerca do Direito Econômico e da hermenêutica para a introdução do leitor à abordagem do princípio da ordem econômica. Após, é apresentada a evolução das classificações de regiões no Brasil, o cenário hodierno das desigualdades regionais brasileiras, fundamentos do princípio da ordem econômica da redução das desigualdades regionais e sociais, o federalismo cooperativo brasileiro, a relação entre o planejamento e o princípio da ordem econômica, a utilização de organismos regionais para a redução das desigualdades regionais (utilizando como exemplo a Superintendência do Desenvolvimento do Nordeste – SUDENE), a relação dos princípios e as regras próprios do Direito Econômico com o princípio da ordem econômica da redução das desigualdades regionais e sociais e a análise do Recurso Extraordinário n. 480.107-8 do Supremo Tribunal Federal. / The current work deals with the fundamentals of the economic order principle of reducing regional and social inequalities present in the article 170, VII, and, in parallel, article 3rd, III, both of the Constitution of the Federative Republic of Brazil of 1988 under the bias of Economic Law. Initially, propaedeutic considerations about economic law and hermeneutics are presented for introducing the reader to the approach to the principle of economic order. Afterwards, the evolution of the classifications of regions in Brazil, the current scenario of Brazilian regional inequalities, foundations of the economic order principle of reducing regional and social inequalities, Brazilian cooperative federalism, the relationship between planning and the principle of the economic order, the use of regional bodies to reduce regional inequalities (using the Superintendência do Desenvolvimento do Nordeste - SUDENE as an example), the relation between principles and rules specific to Economic Law with the principle of the economic order of reducing regional and social inequalities and the analysis of Extraordinary Appeal no. 480.107-8 of the Supreme Court.

Neste trabalho estuda-se o comportamento de redução para a obtenção da liga FeCrAC a partir da pelota auto-redutora feita de minério de cromita, coque de petróleo, ferro-silicio, cal hidratada, sílica e cimento portland ARI. As principais variáveis consideradas são: teor de redutor na composição da pelota, quantidade do redutor, temperatura e tempo. Inicialmente os materiais (cromita, ferro-silício, coque de petróleo, cal hidratada, sílica e cimento Portland ARI), foram caracterizados por: análise química e análise granulométrica. Após a caracterização os materiais (cromita, ferro-silício, coque de petróleo e cimento Portland ARI) foram aglomerados na forma de pelotas juntamente com cal hidratada e sílica para ajuste da basicidade quaternária da escória. A redução das pelotas foi feita num forno de indução que pode atingir temperaturas de até 1973K (1700oC). Todos os experimentos de redução foram realizados no aparato experimental utilizando-se cadinhos de grafite nas temperaturas de 1773K (1500oC), 1823K (1550oC) e 1873K (1600oC). Após os ensaios de redução os produtos obtidos (escória e metal) foram analisados por microscopia ótica, por microscopia eletrônica de varredura (MEV) e análise por EDS. O efeito do aumento da temperatura na redução da cromita é significativo. Houve aumento na velocidade de redução de 4 a 6 vezes com o aumento de 1773K (1500oC) para 1873K (1600oC). Os resultados indicam um efeito marcante de pequenas adições de Fe-Si na velocidade de redução da cromita. Na temperatura de 1773K (1500oC) as adições até ~2% de Fe-Si são benéficas e para adições maiores praticamente não há vantagens técnicas e econômicas. Os tempos necessários para atingir a fração unitária de redução foram 12, 7,5 e 5 minutos para adições de Fe-Si de 0, ~1%, e ~2%, respectivamente; a temperatura de 1823K (1550oC). À temperatura de 1873K (1600oC) as adições de Fe-Si na pelota apresentam também efeitos significativos na velocidade de redução, porém adições de ~1%, e ~2% mostraram os mesmos resultados, indicando que o teor ótimo de adição de Fe- Si na pelota deve estar em torno de 1%. Verificou-se que a utilização de pelotas auto-redutoras contendo 26% em excesso, sobre o estequiométrico, de coque de petróleo aumentou o rendimento de recuperação de Cr de 96% para 98%. O rendimento e a eficiência do processo de auto-redução supera aos processos convencionais de produção de FeCrAC, obtendo-se altas recuperações de cromo na faixa de 96% até 98% para Cr. / The reduction behaviors, at high temperature, of the self-reducing pellets of chromites for production of high carbon ferro-chromium are studied in this work. The influences of the temperature, of the excess of reductant and the small addition of the Fe-Si were analyzed. The materials used (chromites, petroleum coke, Portland cement, hydrated lime and silica) were characterized chemically and by size distribution. The composite pellets (self-reducing) were produced aiming a quaternary basicity of 0.91. The reductant was calculated considering a stoichiometry of reduction and dissolution of 4wt%C in the final metallic phase. The reduction experiments were made in a special system, in argon atmosphere, heated by induction and at temperatures of 1773, 1823 and 1873K. The dried pellets were placed into a pre-heated graphite crucible and left there along up to no gas evolution was observed. The results of the reacted fraction with time were plotted and the obtained product (metallic and slag phases) after experiments were analyzed by optical and by electron micrograph. The chemical estimations were made by micro-analysis (EDS) The effect of increasing the temperature of reduction was sensitive, such that, the reduction rate increased 4 to 6 times with increase of temperature from 1773 to 1873. The small additions, up to 2% of Fe-Si, for substituting the equivalent fixed carbon of the petroleum coke showed to improve substantially the reduction rate, almost doubling it in comparison with pellets without any addition. The use of excess of 26%, over the stoichiometry, of the petroleum coke decreased around 50% of the chromium content in the slag, with relation to pellet without excess. The chromium recovery yield reached 98%. This result coupled with very high reduction rate of self-reducing pellets show the potential for self-reducing processes for ferro-chromium production.

Les Bactéries sulfato-réductrices (BSR) représentent un groupe fonctionnel majeur dans les habitats aquatiques en intervenant dans les processus de minéralisation de la matière organique. En plus de leur implication dans le cycle du carbone et du soufre, les BSR sont considérées comme les principaux producteurs de méthylmercure en milieu côtier, un composé neurotoxique extrêmement bioaccumulable dans les réseaux trophiques. Dans ce contexte, la diversité des BSR dans les sédiments et le panache de l'estuaire de l’Adour (France) a été évaluée par une approche polyphasique incluant le clonage des gènes dsrAB et une méthode de culture haut-débit en microplaques 384 puits. Ces deux techniques ont fourni des données très complémentaires et donc, une meilleure représentation de la diversité sulfato-réductrice réellement présente dans l’estuaire. La réduction des volumes de culture à raison de 100 µL a permis d’améliorer significativement l’efficacité d’isolement des BSR. Près de 200 souches ont été isolées et identifiées à partir des sédiments et du panache de l’estuaire, et plusieurs d'entre elles ont constitué de nouveaux taxons cultivés. En parallèle, un biosenseur luminescent sensible spécifiquement au méthylmercure a été appliqué pour l’étude de la méthylation du mercure par les BSR. Cet outil simple et rapide constitue une bonne alternative aux méthodes de détection chimique traditionnellement utilisées pour évaluer les potentiels de méthylation du mercure des micro-organismes. L’analyse de la production de méthylmercure chez 21 BSR affiliées à la famille des Desulfobulbaceae a permis d’identifier des souches méthylantes, dont certaines ont été identifiées comme abondantes dans les sédiments de l’estuaire. À long terme, l’utilisation du biosenseur pour l’analyse des capacités de méthylation du mercure chez les BSR ou d’autres groupes fonctionnels permettra de mieux connaître la distribution phylogénétique des micro-organismes méthylants et d'appréhender le déterminisme génétique de ces transformations. / Sulfate-Reducing Bacteria (SRB) represent a significant part of the standing microbial communities living in coastal sediments. This functional group is involved in the decomposition and the mineralization of organic matter as well as in the sulfur cycle. In addition, production of methylmercury was shown to be mainly driven by SRB in aquatic ecosystems. Environmental methylation of inorganic mercury constitutes a human health issue due to its neurotoxic effect and its biomagnification in aquatic food webs. In this context, sulfate-reducing diversity was evaluated in anoxic sediments, as well as in the water plume of the Adour estuary. SRB were characterized through a polyphasic approach including dsrAB genes analysis and high throughput isolations in 384-well microplates. As a result, the microplate approach contributed to assess a significant part of the sulfate-reducing community and provided complementary results to the molecular approach. High-throughput SRB isolation permitted a rapid access to numerous but also original strains and around 200 SRB were isolated and identified from the estuarine sediments and the estuarine plume. Beside, the mercury methylation potentials of 21 sulfate reducing strains were determined using a bacterial sensor. All strains were related to the Desulfobulbaceae family and the capacity to produce methylmercury varied a lot. This work permit to identify some methylating strains identified as abundant in the Adour estuarine sediments. On the long view, the use of the biosensor to assess the mercury methylation potential will offer a better knowledge on the distribution of methylating bacteria among the SRB and other functional groups and could help to identify the molecular determinism beside these transformations.

Este trabalho teve como objetivo avaliar o comportamento de arquéias metanogênicas e bactérias redutoras de sulfato na presença de oxigênio, em reatores anaeróbios em batelada, sob condições sulfetogênicas e mesofílicas. Os reatores foram inoculados com lodo anaeróbio proveniente de reator UASB utilizado no tratamento de água residuária de avicultura. Triplicatas de reatores foram alimentadas com meio basal ZINDER, acrescido de acetato de sódio, etanol ou lactato de sódio e sulfato de sódio, de modo a se obter relações DQO/sulfato iniciais de 1,1-1,5. O headspace dos reatores foi preenchido com \'N IND.2\' (100%) acrescido de oxigênio puro comercial (3-3,5 mg/L de oxigênio dissolvido). Os reatores anaeróbios controle foram alimentados com os mesmos substratos orgânicos, entretanto, seu headspace foi preenchido com \'N IND.2\'/\'CO IND.2\' (70/30%). Nos reatores com acetato de sódio, etanol e lactato de sódio as velocidades de produção de metano foram de 0,30 mmol/L.h, 0,41 mmol/L.h e 0,16 mmol/L.h, respectivamente, para os reatores controle. Em relação aos reatores com oxigênio os valores foram de 0,27 mmol/L.h, 0,40 mmol/L.h e 0,08 mmol/L.h, respectivamente. Na presença de acetato, etanol e lactato a redução de sulfato foi de 57% e 97%; 59,6% e 76,6%; 77,5% e 41,9%, respectivamente, nos reatores controle e com oxigênio. Nos reatores com acetato e etanol houve predomínio de organismos do domínio Archaea nos reatores controle (59,2% e 58,8%) e com oxigênio (60,7% e 54,5%), respectivamente. No reator controle contendo lactato, também ocorreu o predomínio de arquéias metanogênicas (56,2%), enquanto na presença de oxigênio houve predomínio de organismos do domínio Bacteria (63,9%). As proporções de BRS nos reatores controle e com oxigênio contendo acetato, etanol e lactato foram de 22% e 17,3%; 28% e 16,9%; 19,5% e 21,9%, respectivamente. O oxigênio não inibiu a metanogênese e nem a redução de sulfato nos reatores contendo acetato e etanol. / This work aimed to evaluate the behavior of methanogenic archaea and sulfate reducing bacteria in the presence of oxygen, using anaerobic batch reactors under sulfidogenic and mesophilic conditions. The reactors were inoculated with anaerobic sludge from UASB reactor treating poultry wastes. Third copies of the reactors were fed with ZINDER medium, increased with sodium acetate, ethanol or sodium lactate and sodium sulfate, in order to get COD/sulfate ratio of 1,1-1,5. The headspace of the reactors was filled with \'N IND.2\' (100%) and increased with oxygen (OD concentration of 3-3.5 mg/L). The anaerobic control reactors were fed with the same organics substrates, however, the headspace was filled with \'N IND.2\'/\'CO IND.2\' (70/30%). The rates of methane production were 0.30 mmol/L.h, 0.41 mmol/L.h and 0.16 mmol/L.h, in acetate, ethanol and lactate controls reactors, respectively. In oxygen reactors, the rates of methane production were 0.27 mmol/L.h, 0.40 mmol/L.h and 0.08 mmol/L.h in acetate, ethanol and lactate reactors, respectively. The rates of sulfate reduction in acetate, ethanol and lactate reactors were 57% and 97%; 59.6% and 76.6%; 77.5% and 41.9%, respectively, in control reactors and oxygen reactors. In acetate and ethanol reactors, were verified predominance of Archaea domain in control reactors (59.2% and 58.8%) and oxygen reactors (60.7% and 54.5%), respectively. In lactate control reactor also was verified predominance of Archaea domain (56.2%), whereas in lactate oxygen reactors there was predominance of cells belonging to Bacteria domain (63.9%). BRS ratio in acetate, ethanol and lactate control reactors and oxygen reactors corresponded to 22% and 17.3%; 28% and 16.9%; 19.5% and 21.9%, respectively. The addition of oxygen didn\'t inhibit the methanogenesis and sulfate reduction in acetate reactors and in ethanol reactors.

Os compostos de coordenação de rutênio têm recebido grande atenção para tratamento do câncer. Em particular, estudos do grupo mostraram que um metalofármaco de dirutênio(II,III) com o fármaco anti-inflamatório não-esteróide ibuprofeno apresenta boa atividade para tumor cerebral maligno. Neste contexto, o presente trabalho teve como objetivo ampliar os estudos com a obtenção de novos complexos, investigar as interações dos metalofármacos com moléculas de interesse biológico e preparar materiais híbridos destes com ciclodextrina. Desenvolveu-se metodologia sintética para a preparação de dois novos metalofármacos de dirutênio(II,III) de fórmula geral [Ru2(O2CR)4Cl], em que O2CR = cetoprofenato (cet) ou fenbufenato, a partir do precursor [Ru2(O2CH3)4Cl]. Os novos complexos foram caracterizados principalmente por meio de técnicas espectroscópicas, difratometria de raios x e análise térmica. Estudos de reatividade foram realizados para a espécie [Ru2(O2CH3)4(H2O)2]+, obtida a partir do precursor [Ru2(O2CH3)4Cl] em solução aquosa. Constantes de equilíbrio e parâmetros termodinâmicos para as reações de substituição axial água-cloreto, e também parâmetros cinéticos das reações deste complexo com os aminoácidos glicina, triptofano, cisteína e histidina, e com os agentes redutores glutationa e ácido ascórbico, foram determinados. Estudos sobre as interações com a proteína albumina do soro humano (HSA) foram efetuados para os complexos [Ru2(O2CH3)4Cl] e [Ru2(cet)4Cl], e também para o derivado análogo de ibuprofenato (ibp), [Ru2(ibp)4Cl]. Novos materiais híbridos contendo os complexos [Ru2(O2CR)4Cl] (O2CR = ibuprofenato ou cetoprofenato) e hidroxipropil-&#946;-ciclodextrina foram obtidos, usando-se a técnica de spray-drying, e caracterizados. / Ruthenium compounds have received great attention for cancer therapy. In particular, studies from our research group have found that a metallodrug of diruthenium(II,III) with the non-steroidal anti-inflammatory drug ibuprofen, has good activity for malignant brain tumor. In this context, the main purposes of this work were to improve these studies, to investigate some interactions of these metallodrugs with biologically relevant molecules, and also to prepare hybrid materials of these complexes with cyclodextrin. Synthetic methodologies were developed to prepare two novel diruthenium(II,III) metallodrugs, with the general formula [Ru2(O2CR)4Cl], where O2CR = ketoprofen (ket) or fenbufen starting from the precursor [Ru2(O2CH3)4Cl]. The novel complexes were characterized mainly by spectroscopical techniques, X-rays difractometry and termal analysis. Reactivity studies were performed for the species [Ru2(O2CH3)4(H2O)2]+ obtained from the precursor [Ru2(O2CH3)4Cl] in aqueous solution. Equilibrium constants and thermodynamic parameters for water-chloride axial substitutions, and also kinetic parameters for the reactions of this complex with the amino acids glycine, tryptophan, cysteine and histidine, and the reducing agents glutathione and ascorbic acid, were determined. Studies on the interactions with the human serum albumin (HSA) protein were performed for the complexes [Ru2(O2CH3)4Cl] and [Ru2(ket)4Cl], and also for the analogue derivative of the ibuprofen drug (ibp), [Ru2(ibp)4Cl]. Novel hybrid materials containing complexes [Ru2(O2CR)4Cl] (O2CR = ibuprofenato or ketoprofenato) and &#946;-hydroxypropyl-cyclodextrin were prepared by using spray-drying technique and characterized.

非傳染性疾病是目前全球最常見的疾病之一。不健康的食相信是導致非傳染性疾病增加的主要因素之一。因此，我們就食對乳腺癌的形成和膽固醇代謝調控的影響進行了研究。 / 在去除卵巢的祼鼠模型中，我們研究了長期和短期熱量限制對乳腺癌腫瘤增殖的影響。14週齡的小鼠被隨機分為5組：自由攝食組 (AL)；熱量攝入控制在AL80% 的20%CCR組；熱量攝入控制在AL的70% 的30%CCR組；熱量攝入控制在AL的65% 的35%CCR組和短期熱量限制 （SCR）組 (前3.5週熱量攝入控制在AL的65%，之後的13.5週自由攝食)。10週後，熱量限制組的腫瘤體積明顯較AL組小 (P < 0.05)。排除攝食對體重的影響，SCR組的腫瘤重量明顯較AL組小 (P < 0.05)。本實驗結果表明，在此動物模型中，短期熱量限制能有效抑制乳腺癌細胞的增殖。 / 此外，我們還研究了芹菜素在肝細胞中對膽固醇代謝的影響。芹菜素是一種常見的黃酮類化合物。研究發現，在WRL-68細胞中，芹菜素能夠劑量依賴性的抑制3 - 羥基-3 - 甲基 - 戊二酸單酰輔酶還原酶 (HMGCR)和固醇調節元件結合蛋白-2 (SREBP-2) 信使RNA和蛋白的表達及其啟動子的轉錄活性。綜上所述，在肝細胞中，芹菜素能有效抑制HMGCR和SREBP-2的表達，從而達到降低膽固醇的效果。 / 總括而言，本研究表明在去除卵巢的祼鼠模型中，短期熱量限制能有效抑制乳腺癌細胞的生長和芹菜素能有效抑制HMGCR和SREBP-2的表達。 / Non-communicable diseases (NCD) are one of the leading causes of mortality in the developed and under-developing countries. Diet is a major risk factor of NCD. In the present study, effects of diet modification on breast cancer development and cholesterol metabolism were investigated. / In the first part of this study, the effect of chronic and short-term calorie restriction (CR) on breast tumor growth in ovariectomized nude mice was investigated. The calorie-restricted dietary regimen limited the total fat intake only. 14 week-old ovariectomized female nude mice were randomly assigned to ad libitum fed (AL), 20%CCR (17-week 80% of AL), 30%CCR (17-week 70% of AL), 35%CCR (17-week 65% of AL) and short-term CR (3.5-week 65% of AL followed by 13.5-week 100% AL consumption) groups. Starting from 10 weeks after transplant of cells, the tumor volumes in all calorie-restricted groups were significantly smaller (P < 0.05) than that in ad libitum control. At sacrifice, the tumor weight in short-term CR was significantly smaller (P < 0.05) than that in ad-libitum control after normalized with body weight. This indicated that short-term CR could suppress tumor in this model. / In the second part of this study, the effect of apigenin on cholesterol metabolism was investigated. Apigenin is one of the most abundant flavonoids. In the present study, we investigated the effect of apigenin on several cholesterol-related gene expression in hepatic cells. In WRL-68 cells treated with apigenin, promoter transcription activity, mRNA and protein expression of HMGCR and SREBP-2 were significantly decreased in a dose-dependent manner. Taken together, we concluded that apigenin inhibited HMGCR and SREBP-2 gene expressions in hepatic cells, which might elicit the hypocholesterolemic effects. / In conclusion, our study has demonstrated that short-term CR could significantly block the breast tumor growth in a mice model and apigenin could inhibit the expression of HMGCR and SREBP-2 in liver cell lines. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Wong, Tsz Yan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 83-99). / Abstracts also in Chinese. / ACKNOWLEGEMENTS --- p.i / ABSTRACT --- p.ii / 摘要 --- p.iv / list of abbreviations --- p.v / list of figures --- p.vii / list of tables --- p.IX / TABLE of CONTENTS --- p.X / Chapter 1 --- CHAPTER 1 --- p.1 / General Introduction --- p.1 / Chapter 1.1 --- Calorie Restriction and the Prevention of Postmenopausal Breast Cancer --- p.2 / Chapter 1.1.1 --- Breast Cancer --- p.2 / Chapter 1.1.2 --- Epidemiology of Excess Body Weight and Cancer Risk --- p.3 / Chapter 1.1.3 --- Calorie Restriction and Cancer Prevention --- p.7 / Chapter 1.1.4 --- Mechanistic Targets of Calorie Restriction --- p.8 / Chapter 1.1.4.1 --- Effect of Calorie Restriction on Estrogen --- p.8 / Chapter 1.1.4.1 --- Effect of Calorie Restriction on Cell Cycle Regulation --- p.12 / Chapter 1.1.4.1 --- Effect of Calorie Restriction on Apoptosis --- p.14 / Chapter 1.2 --- Effect of Apigenin on Cholesterol Homeostasis --- p.17 / Chapter 1.2.1 --- Cardiovascular Disease and Blood Cholesterol --- p.17 / Chapter 1.2.2 --- Molecular Regulation of Cholesterol Metabolism --- p.21 / Chapter 1.2.2.1 --- HMG-CoA Reductase --- p.21 / Chapter 1.2.2.2 --- CYP7A1 --- p.24 / Chapter 1.2.2.3 --- Apolipoprotein A-1 --- p.26 / Chapter 1.2.2.4 --- Low Density Lipoprotein Receptor --- p.29 / Chapter 1.2.2.5 --- Sterol Regulatory Element Binding Proteins --- p.31 / Chapter 1.2.3 --- Flavonoid and its Association with Cholesterol Metabolism --- p.36 / Chapter 1.2.4 --- Apigenin: A Potential Alternative --- p.39 / Chapter 2 --- CHAPTER 2 --- p.41 / MATERIALS AND METHODS --- p.41 / Chapter 2.1 --- Chemicals and Materials --- p.41 / Chapter 2.1.1 --- Chemicals --- p.41 / Chapter 2.1.2 --- Plasmids --- p.41 / Chapter 2.2 --- Cell Culture --- p.41 / Chapter 2.2.1 --- Maintainance of Cells --- p.41 / Chapter 2.2.2 --- Preparation of Cell Stock --- p.42 / Chapter 2.2.3 --- Cell Recovery from Liquid Nitrogen Stock --- p.42 / Chapter 2.3 --- Measurement of Cell viability --- p.43 / Chapter 2.4 --- Semi-Quantitative and Quantitative RT-PCR Assay --- p.43 / Chapter 2.4.1 --- RNA Isolation and cDNA Synthesis --- p.43 / Chapter 2.4.2 --- Quantitative Real Time PCR Assay --- p.43 / Chapter 2.4.2.1 --- Real Time PCR Using TaqMan Probe --- p.43 / Chapter 2.4.2.2 --- Real Time PCR Using SYBR Green Dye --- p.44 / Chapter 2.4.2.3 --- Statistical Analysis of 2⁻ΔΔ{U+A7F0}{U+1D40} Comparative Gene Expression --- p.44 / Chapter 2.5 --- Western Blot Analysis --- p.46 / Chapter 2.6 --- Measurement of Promoter Activity --- p.46 / Chapter 2.6.1 --- Plasmid Preparation --- p.46 / Chapter 2.6.2 --- Transient Transfection and Dual-Luciferase Assay --- p.47 / Chapter 2.7 --- Animal Experiment Design --- p.47 / Chapter 2.7.1 --- Animal Model and Dietary Regimens --- p.47 / Chapter 2.7.2 --- Tissue Sample Collection --- p.50 / Chapter 2.7.3 --- Plasma Estradiol Determination --- p.50 / Chapter 2.7.4 --- Protein and RNA extraction --- p.50 / Chapter 2.8 --- Statistical Analysis --- p.50 / Chapter 3 --- Chapter 3 --- p.51 / EFFECT OF CHRONIC AND short-term calorie restriction on breast tumor growth in ovariectomized nude mice --- p.51 / Chapter 3.1 --- Introduction --- p.51 / Chapter 3.2 --- Objectives --- p.52 / Chapter 3.3 --- Results --- p.53 / Chapter 3.3.1 --- Food Intakes, Body, Liver and Uterus Wet Weights of the Mice --- p.53 / Chapter 3.3.2 --- Tumor Development --- p.57 / Chapter 3.3.3 --- Plasma Estradiol Level --- p.62 / Chapter 3.3.4 --- Estradiol Responsive Gene expression in Tumors --- p.63 / Chapter 3.3.5 --- Cell Apoptotic and Cell Cycle-Regulated Protein expression in Tumors --- p.65 / Chapter 3.4 --- Discussion --- p.67 / Chapter 4 --- CHAPTER 4 --- p.69 / Apigenin inhibits the expression of hmg-coa reductase and srebp-2 in hepatic cells --- p.69 / Chapter 4.1 --- Introduction --- p.69 / Chapter 4.2 --- Objectives --- p.70 / Chapter 4.3 --- Results --- p.70 / Chapter 4.3.1 --- Effect of Apigenin on Cell Viability --- p.70 / Chapter 4.3.2 --- Effect of Apigenin on HMGCR, CYP7A1, LDLR, ApoA-1, SREBP-1 and SREBP-2 mRNA expressions --- p.72 / Chapter 4.3.3 --- Effect of Apigenin on HMGCR, LDLR, ApoA-1 and SREBP-2 Promoter Transcription Activity --- p.75 / Chapter 4.3.4 --- Effect of Apigenin on HMGCR, SREBP-1 and SREBP-2 Protein Expression --- p.77 / Chapter 4.3.5 --- Role of Estrogen Receptor in Apigenin induced SREBP-2 Inhibition --- p.79 / Chapter 4.4 --- Discussion --- p.80 / Chapter 5 --- CHAPTER 5 --- p.82 / SUMMARY --- p.82 / References --- p.83