Made available in DSpace on 2015-05-08T14:59:33Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 4124460 bytes, checksum: b1308b52af8710e348b248c71f0f952b (MD5) Previous issue date: 2011-09-20 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The use of vegetable fibers as a reinforcing agent in geopolymers, represents an alternative to the replacement of manufactured fibers as a reinforcing agent. The pineapple leaf, an abundant plant in the region and with easy cultivation and processing, which produces low modulus of good mechanical performance fibers, emerges as an ecologically viable and sustainable alternative. In this work, fiber ananas comosus and agave sisalana have been characterized by a process of selection, cleaning, washing, drying and cutting of fresh blankets for the production of composites based on geopolymer matrix. The good mechanical performance and the possibility of using industrial waste materials and the abundance of precursors materials of the region favor the use of geopolymer matrix in obtaining the bodies of proof used in this study. The use of vegetable fibers (ananas comosus and agave sisalana) as a reinforcing agent in geopolymer to obtain composites provided gain in quality to the mechanical properties of the matrix. We conclude that the ratio Si / Al is one of the main variables controlling the process of geopolymerization. However, a better relationship of the interface fiber / matrix produces accommodation and better performance with and absorption of considerable effort on the part of the composite. This behavior is influenced by variations in temperature, pressure and flow of geopolymer used as a matrix. During this study, thermal analysis techniques (TG, DTG, DTA), microscopy (MEV) and spectroscopy (XRF, DRX) as well as mechanical and chemical tests were used to characterize the materials used in this work. Also presented are the results of mechanical tests of composites with sisal and pineapple tree fibers, and micro-structural behavior, when it will be possible to compare the benefits of vegetable fiber added to the performance and resistance of bodies of proof. / O uso de fibras vegetais como agente de reforço em geopolímeros, representa uma alternativa na substituição de fibras manufaturadas como agente de reforço, a folha do abacaxizeiro, uma planta abundante na região e de fácil cultivo e processamento, que produz fibras de baixo módulo de ótimo desempenho mecânico, surge como alternativa ecologicamente viável e sustentável. Neste trabalho, fibras de ananas comosus e agave sisalana foram caracterizadas passaram por um processo de seleção, limpeza, lavagem, secagem e corte das mantas in natura para produção de compósitos a base de matriz geopolimérica. O bom desempenho mecânico aliado a possibilidade de utilização de resíduos industriais e a abundância de materiais precursores da região favorecem a utilização do geopolímero como matriz na obtenção dos corpos-de-prova usados nesse estudo. A utilização de fibras vegetais (ananas comosus e agave sisalana) como agente de reforço em geopolímero para obtenção de compósitos proporcionou ganho de qualidade às propriedades mecânicas da matriz. Concluímos que a razão Si/Al é uma das principais variáveis de controle do processo de geopolimerização, todavia uma melhor relação da interface fibra/matriz produz acomodação e melhor desempenho com absorção de esforço considerável por parte do compósito. Esse comportamento é influenciado por variações de temperatura, pressão e fluidez do geopolímero utilizado como matriz. Durante esse estudo, técnicas de análise térmica (TG, DTG, DTA), microscopia (MEV) e espectroscopia (XRF, DRX), bem como ensaios mecânicos e químicos, foram utilizadas para caracterizar os materiais utilizados nesse trabalho, também são apresentados os resultados de ensaios mecânicos dos compósitos com fibras de sisal e abacaxizeiro e seu comportamento micro-estrutural, quando será possível comparar os benefícios que as fibras vegetais acrescentaram ao desempenho e resistência dos corpos-de-prova.

Made available in DSpace on 2014-12-17T14:57:45Z (GMT). No. of bitstreams: 1 DorivaldaSMN.pdf: 3293308 bytes, checksum: e37080f4f72e81ac421fcaf0fec21fa8 (MD5) Previous issue date: 2005-12-16 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / In the last decades there was a significant increasing of the numbers of researchers that joint efforts to find alternatives to improve the development of low environmental impact technology. Materials based on renewable resources have enormous potentials of applications and are seen as alternatives for the sustainable development. Within other parameters, the sustainability depends on the energetic efficiency, which depends on the thermal insulation. Alternative materials, including vegetal fibers, can be applied to thermal insulation, where its first goal is to minimize the loss of energy. In the present research, it was experimentally analyzed the thermal behavior of fiber blankets of sisal (Agave sisalana) with and without surface treatment with oxide hidroxide (NaOH). Blankets with two densities (1100/1200 and 1300/1400 g/m2) were submitted to three rates of heat transfer (22.5 W, 40 W and 62.5 W). The analysis of the results allowed comparing the blankets treated and untreated in each situation. Others experiments were carried out to obtain the thermal conductivity (k), heat capacity (C) and the thermal diffusivity (α) of the blankets. Thermo gravimetric analyses were made to the verification of the thermal stability. Based on the results it was possible to relate qualitatively the effect of the heat transfer through the sisal blankets subjected to three heat transfer rates, corresponding to three temperature values (77 ?C, 112 ?C e 155 ?C). To the first and second values of temperature it was verified a considerable reduction on the rate of heat transfer; nevertheless, to the third value of temperature, the surface of the blankets (treated and untreated) in contact with the heated surface of the tube were carbonized. It was also verified, through the analyses of the results of the measurements of k, C e α, that the blankets treated and untreated have values near to the conventional isolating materials, as glass wool and rock wool. It could be concluded that is technically possible the use of sisal blankets as constitutive material of thermal isolation systems in applications where the temperature do not reach values greater than 112 ?C / Nas ?ltimas d?cadas, t?m sido grandes os esfor?os dos pesquisadores na busca por alternativas sustent?veis e conhecimentos sobre como se poder? continuar promovendo o desenvolvimento sem que isso ocorra de forma agressiva ao ambiente. Materiais oriundos de fontes renov?veis possuem grande potencial de aplicabilidade e s?o vistos como alternativas para um desenvolvimento sustent?vel. Dentre outros par?metros, a sustentabilidade depende da efici?ncia energ?tica e essa, por sua vez, depende de isolantes t?rmicos. Materiais alternativos, entre eles as fibras vegetais, podem ser aplicadas para fins de isolamento t?rmico, cujo principal objetivo ? minimizar as perdas de energia. Na presente pesquisa, analisou-se experimentalmente a aplicabilidade de mantas de fibras de sisal (Agave sisalana), in natura e com tratamento superficial com hidr?xido de s?dio (NaOH), ? isola??o t?rmica. Foram utilizadas mantas de duas gramaturas (1100/1200 e 1300/1400 g/m2) submetidas a tr?s taxas de transfer?ncia de calor (22,5 W, 40 W e 62,5 W). A an?lise dos resultados obtidos permitiu comparar a capacidade de isola??o das mantas tratada e in natura em cada situa??o. Ensaios foram realizados para determina??o da condutividade t?rmica (k), capacidade calor?fica (C) e a difusividade t?rmica (α) das mantas; a estabilidade t?rmica foi verificada por meio de an?lise termogravim?trica (TGA). Com base nos resultados, foi poss?vel relacionar qualitativamente o efeito da transfer?ncia de calor atrav?s das mantas de sisal submetidas a tr?s condi??es de aquecimento, correspondentes a tr?s valores de temperatura (77 ?C, 112 ?C e 155 ?C). Nas duas condi??es iniciais, verificou-se que as mantas de sisal proporcionaram uma significativa redu??o da taxa de transfer?ncia de calor. Na terceira condi??o (155 ?C), contudo, as superf?cies das mantas (tratadas e in natura) em contato com a superf?cie aquecida do tubo ficaram carbonizadas. Por meio das an?lises dos resultados das medi??es de k, C e α, constatou-se que as mantas tratadas e in natura apresentaram valores bem pr?ximos aos de materiais isolantes comerciais (l? de vidro e l? de rocha). P?de-se concluir que mantas de sisal podem ser empregadas como material constituinte de sistemas de isola??o t?rmica para aplica??es em que a temperatura n?o ultrapasse 112 ?C

Made available in DSpace on 2014-12-17T14:08:47Z (GMT). No. of bitstreams: 1 LoivaLSB_DISSERT.pdf: 3990836 bytes, checksum: 3537e4304659ead550f1c758b72dbbce (MD5) Previous issue date: 2010-07-19 / Currently, the oil industry is the biggest cause of environmental pollution. The objective was to reduce the concentration of copper and chromium in the water produced by the oil industry. It was used as adsorbent natural sisal fiber Agave sp treated with nitric acid and sodium hydroxide. All vegetable fibers have physical and morphological properties that enablies the adsorption of pollutants. The basic composition of sisal is cellulose, hemicellulose and lignin. The features are typically found in the characterization of vegetable fibers, except the surface area that was practically zero. In the first stage of adsorption, it was evaluated the effect of temperature and time skeeking to optimize the execution of the factorial design. The results showed that the most feasible fiber was the one treated with acid in five hours (30?C). The second phase was a factorial design, using acid and five hours, this time was it determined in the first phase. The tests were conducted following the experimental design and the results were analyzed by statistical methods in order to optimize the main parameters that influence the process: pH, concentration (mol / L) and fiber mass/ metal solution volume. The volume / mass ratio factor showed significant interference in the adsorption process of chromium and copper. The results obtained after optimization showed that the highest percentages of extraction (98%) were obtained on the following operating conditions: pH: 5-6, Concentration: 100 ppm and mass/ volume: 1 gram of fiber/50mL solution. The results showed that the adsorption process was efficient to remove chromium and copper using sisal fibers, however, requiring further studies to optimize the process. / A ind?stria de petr?leo ? atualmente uma das principais causadoras da polui??o ambiental. O objetivo deste trabalho foi reduzir a concentra??o de cobre e cromo na ?gua produzida pela ind?stria petrol?fera. Foi usado como adsorvente a fibra de sisal natural, tratada com ?cido n?trico e hidr?xido de s?dio. Todas as fibras vegetais possuem caracter?sticas f?sicas e morfol?gicas que possibilitam a adsor??o de poluentes. A composi??o b?sica do sisal ? celulose, hemicelulose e lignina. As caracter?sticas encontradas na caracteriza??o s?o t?picas de fibras vegetais, com exce??o da ?rea superficial que foi praticamente zero. Na primeira fase da adsor??o foi realizado um estudo a temperatura (30?C, 45?C e 60?C) e tempo para otimizar a realiza??o do planejamento fatorial. Os resultados mostraram que a fibra mais vi?vel para o estudo ? a fibra tratada com ?cido ? 30?C durante 5 horas. A segunda fase foi a do planejamento fatorial, usando a fibra ?cida e o tempo de cinco horas determinado na primeira fase. Os ensaios foram efetuados seguindo o planejamento Fatorial 2 3. Os resultados obtidos foram analisados, atrav?s de m?todos estat?sticos, visando a otimiza??o dos principais par?metros que influenciam no processo: pH, concentra??o (mol/L) e rela??o massa de fibra (g)/ volume de solu??o (mL). Os resultados do planejamento descrevem, o fator concentra??o e o fator massa/volume apresentam interfer?ncia significativa no processo de adsor??o do cromo e cobre. Os resultados, ap?s a otimiza??o, demonstraram que os maiores percentuais de extra??o (98 %) foram obtidos nas seguintes condi??es operacionais: pH: 5-6, Concentra??o: 100 ppm e a rela??o massa /volume: 1grama de fibra/50mL de solu??o. Observou-se que o processo foi eficiente com rela??o ? adsor??o do cromo e cobre, contudo s?o necess?rios mais estudos para a otimiza??o do processo.

Le Mexique se caractérise par la présence sur son territoire de nombreuses espèces d’agave qui peuvent être cultivées ou non. En particulier l’Agave tequilana Weber var. azul a une grande importance économique, car elle constitue la principale matière première pour l’élaboration de la tequila. Les agaves durant leur développement, qui dure plusieurs années, accumulent des réserves de sucres constitués par des fructanes. Actuellement, l’optimisation de l’hydrolyse des fructanes d’agave est surtout importante pour l’industrie de la tequila. Elle permettra d’améliorer les rendements d’extraction des sucres. La méthode classique d’hydrolyse des fructanes est constituée principalement d’un procédé de cuisson des agaves crus. L’utilisation d’enzymes spécifiques pour réaliser ce même procédé d’hydrolyse suscite un récent intérêt industriel, parce qu’il permettrait une réduction de la consommation d’énergie. Les fructanes d’agave présentent des structures complexes, les résidus de fructose sont reliés par des liaisons osidiques de type β (2→1) et β (2→6), et la structure est fortement branchée. Il est nécessaire de comprendre les changements de structure des fructanes en fonction de l’étape de croissance des plantes, pour connaître la variabilité naturelle du substrat utilisé pour l’hydrolyse. D’autre part, il est important de découvrir de nouvelles enzymes susceptibles d’hydrolyser de manière spécifique les fructanes d’agave, et les caractériser biochimiquement, pour arriver à une meilleure connaissance de l’intéraction enzyme-substrat qui permettra le développement de nouvelles applications industrielles possibles pour les fructanes d’Agave tequilana. Dans ce travail, la première partie est consacrée à la détermination de la composition en sucres solubles et à la caractérisation de la structure des fructanes d’Agave tequilana présents dans des plantes d’âges différents. Puis, dans la deuxième partie, la purification et la caractérisation biochimique d’une fructanase isolée d’une souche de levure Kluyveromyces marxianus obtenue à partir du procédé de fermentation du mezcal (boisson d’agave distillée) a été étudiée. L’activité de cette enzyme a été comparée à un cocktail enzymatique commercial le fructozyme®. Finalement, dans une troisième partie, des levures isolées de la fermentation de différents types de mezcal ont été criblées et ont permis la sélection de souches capables de dégrader spécifiquement les fructanes d’Agave / Mexico has a high diversity of Agave plants, which could be cultivated or not. The most economically important is Agave tequilana Weber var. azul, because it is the raw material for the tequila elaboration process. As agaves grow, they accumulate reserve sugars as fructans. Actually, optimizing the A. tequilana fructans hydrolysis, in order to increase the sugar yield, is important to the tequila industry. Traditionally, agaves are cooked to hydrolyze the fructans. However, using enzymes for hydrolysis may reduce energy consumption and increase sugar yields.The fructans of A. tequilana have a complex structure, composed of fructose chains with β (2→1) and β (2→6) linkages with branching points. It is important to understand how the structure of these molecules changes as a function of plant growth, in order to know the natural variability of the substrate that must be hydrolysed. It is also necessary to find new enzymes for the efficient hydrolysis of A. tequilana fructans, and to characterize them biochemically for a better understanding of the enzyme-substrate interaction.The present work has three parts that focuses separately on each of these needs: First, characterizing the water soluble carbohydrates and the structure of the A. tequilana fructans as a function of the plant’s growth (age). Second, purifying and biochemically characterizing a fructanase from Kluyveromyces marxianus yeast isolated from the fermentation of mezcal, and comparing it to a commercial cocktail (Fructozyme®). Third, a screening of enzymes from yeasts used to ferment mezcal, in order to determine their ability to hydrolyze A. tequilana fructans

Made available in DSpace on 2015-09-25T12:22:45Z (GMT). No. of bitstreams: 1 Alexsandra Conceicao Apolinario.pdf: 10433761 bytes, checksum: 7fc2291a08f9e9ee62b7ebc48a58bfd1 (MD5) Previous issue date: 2014-03-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Agave sisalana is a specie widely grown in northeastern Brazil for production of sisal fiber, Bahia and Paraíba being the world's largest producers. The process of decortication of the leaves of A. sisalana implies loss of more than 95% of the plant in the form of solid waste (bagasse) and liquid waste (juice). In addition, parts of plant such as boles are not used. An economic decline in sisal crop from Brazil is also reported by government agencies, which have driven the need to add new values to this species. This study aimed to obtain and characterize different products of pharmaceutical interest from the boles and leaves (wastes from decortication) from A. sisalana. The boles and wastes (bagasse and juice) were subjected to processing steps for obtaining the extracts and herbal drugs, which were characterized according to pharmacopoeial parameters and metabolites of interest therein were screened (Chapter 2). After analyzing the results obtained by initial characterization, the aqueous extracts from boles were used for obtaining the polysaccharide inulin which was isolated after steps of precipitation by physicochemical methods and purified by ion exchange chromatography. Analyses by different instrumental techniques were used to characterize the product (Chapter 3). Preliminary in vitro screenings for prebiotic activity was carried out in the aqueous extracts and polysaccharides dried by spray drying. Both samples were characterized by thermogravimetry and metabolites of interest were quantified (Chapter 4). Pectic polysaccharides were extracted from the wastes and subjected to various steps of purification involving deproteinzation and ion exchange chromatography. Instrumental techniques were used for structural characterization of these samples (Chapter 5). The inulin obtained from boles showed characteristics similar to those available commercially obtained from other species. The in vitro screening indicated that the dried extract of A. sisalana exhibis prebiotic potential and could probably be an economically viable alternative because the isolation of inulin requires steps that demands time and high costs and result in low yields. The characterization of polysaccharides extracted from wastes indicated typical structures of pectin. Thus, this study reports new opportunities to add value to A. sisalana by recovering products of pharmaceutical interest. / Agave sisalana é uma espécie amplamente cultivada no nordeste do Brasil, visando à produção da fibra sisal, sendo a Bahia e a Paraíba os maiores produtores mundiais. O processo de decorticação das folhas de A. sisalana implica no desperdício de mais de 95% da planta na forma dos resíduos sólido (bagaço) e líquido (suco), além disso, outras partes da planta, como o caule não são utilizadas. Aliado a isso, um declínio econômico na cultura sisaleira no Brasil é relatado por órgãos governamentais, o que tem direcionado à necessidade de agregar novos valores a esta espécie. Diante deste contexto, esta pesquisa objetivou obter e caracterizar diferentes produtos de interesse farmacêutico a partir do caule e folha (resíduos de decorticação) de A. sisalana. O caule e os resíduos (divididos em bagaço e suco) foram submetidos a etapas de processamento para obtenção de drogas vegetais e extratos, os quais foram caracterizados quanto a parâmetros farmacopéicos e metabólitos de interesse presentes foram quantificados (Capítulo 2). Após análise dos resultados obtidos pela caracterização inicial, os extratos aquosos do caule foram destinados à obtenção do polissacarídeo inulina, o qual foi isolado após etapas de precipitação por métodos físicoquímicos e purificação por cromatografia de troca iônica. As análises por diferentes técnicas instrumentais permitiram caracterizar o produto (Capítulo 3). Um screening in vitro preliminar de atividade prebiótica foi realizado nos extratos aquosos do caule secos por nebulização e polissacarídeos obtidos deste extrato também secos em spray dryer, ambas as amostras foram caracterizadas por termogravimetria e tiveram metabólitos de interesse quantificados (Capítulo 4). Polissacarídeos pécticos foram extraídos dos resíduos de decorticação e submetidos a diversas etapas de purificação que incluíram desproteinzação e cromatografia de troca iônica. Técnicas instrumentais foram empregadas para caracterização estrutural dos mesmos (Capítulo 5). A inulina obtida do caule apresentou características semelhantes àquelas comercialmente disponíveis obtidas de outras espécies. O screening in vitro indicou que o extrato seco do caule de A. sisalana apresentou potencial prebiótico e provavelmente seria como uma alternativa economicamente viável uma vez que o isolamento da inulina requer etapas que demandam tempo, geram alto custo e resultam em baixo rendimento. A caracterização dos polissacarídeos obtidos dos resíduos revelou estruturas comuns à pectina. Assim, esta pesquisa relata novas possibilidades de agregar valor ao A. sisalana por meio da obtenção de produtos de interesse farmacêutico.

Submitted by Jean Medeiros (jeanletras@uepb.edu.br) on 2016-03-02T16:49:48Z No. of bitstreams: 2 PDF - Juliana Patrícia de Luna Vieira.pdf: 1566750 bytes, checksum: 6e63c4bf04d69f696ff99b689380db13 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Secta BC (secta.csu.bc@uepb.edu.br) on 2016-06-13T20:30:18Z (GMT) No. of bitstreams: 2 PDF - Juliana Patrícia de Luna Vieira.pdf: 1566750 bytes, checksum: 6e63c4bf04d69f696ff99b689380db13 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2016-06-13T20:30:27Z (GMT). No. of bitstreams: 2 PDF - Juliana Patrícia de Luna Vieira.pdf: 1566750 bytes, checksum: 6e63c4bf04d69f696ff99b689380db13 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2014-08-27 / Agave sisalana is a plant of Mexican origin that is characterized by providing the stiffest fiber in the world: the sisal. In Brazil, this plant is an important source of income for farmers in semi-arid regions mainly in the states of Bahia and Paraíba. The ability to create jobs is related to maintenance of the crops, harvesting, refining, processing fiber, industrialization and production of crafts. The aim of this study was to determine the antimicrobial, antioxidant and cytotoxicity of Agave sisalana Perrine in wastes obtained from the leaves of defibrillation. Antibacterial activity was determined against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and against fungiCandida albicans. The antioxidant activity was performed with the method of DPPH. The cytotoxicity was detected in HeLa cells using the cell proliferation reagent WST-1. The antibacterial activity was found in RL0 (E. coli, P. aeruginosa) and EEB-1 (S. aureus). Activity against C. albicans was found in RL-0, EEB-0 and EEB-1. Ethanol extracts have antioxidant activity, this analysis was not performed with liquid waste because they do not solubilized in ethanol. The cytotoxicity assay showed that the RL-0 is toxic at concentrations that have antimicrobial activity. The RL-1, EEB-0 and EEB-1, above extracts showed cell viability of the positive control (cells + DMSO), when the concentrations of 5 mg/ml, 1 mg/ml and 1 mg/mL, respectively. These results demonstrate that Agave sisalana can be a source of new therapeutic assets. / A Agave sisalana é uma planta de origem mexicana que se destaca por fornecer a fibra mais dura do mundo: o sisal. No Brasil, essa planta representa uma importante fonte de renda para agricultores de regiões semi-áridas principalmente dos estados da Bahia e Paraíba. A capacidade de gerar empregos está relacionada à manutenção das lavouras, colheita, desfibramento, beneficiamento da fibra,industrialização e confecção de artesanato. O objetivo desse trabalho foi determinar as atividades antimicrobiana, antioxidante e de citotoxicidade da Agave sisalana Perrine, em resíduos obtidos da desfibrilação das folhas. Foram utilizados os resíduos líquido (RL-0), líquido seco em spray drying (RL-1), extrato etanólico concentrado bruto do resíduo sólido (EEB-0) e extrato etanólico concentrado bruto seco em spray drier do resíduo sólido (EEB-1). A atividade antibacteriana foi determinada em cepas de Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosae a antifúngica em cepa de Candida albicans. A atividade antioxidante foi realizada com o método do 2,2-difenil-1-pricril-hidrazil (DPPH). A citotoxicidade foi verificada em células HeLa utilizando o reagente de proliferação celular composto terrazólico (WST-1). A atividade antibacteriana foi encontrada no RL-0 (E. coli, P. aeruginosa) e no EEB-1 (S.aureus). A atividade contra C. albicans foi encontrada em RL-0, EEB-0 e EEB-1. Os extratos etanólicos apresentam atividade antioxidante. O ensaio de citotoxicidade demonstrou como esperado que o RL-0 é tóxico nas concentrações que apresentaram atividade antimicrobiana. Os extratos RL-1, EEB-0 e EEB-1, mostram viabilidade celular acima do controle positivo (células + DMSO) quando nas concentrações de 5 mg/mL, 1 mg/mL e 1 mg/mL, respectivamente. Esses resultados demonstram que os resíduos de decorticação de Agave sisalana, que atualmente são desperdiçados, podem ser fonte de novos ativos terapêuticos.

Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-04-24T16:05:47Z No. of bitstreams: 1 DOUGLAS ALEXANDRE SARAIVA LEÃO - TESE PPGEP 2014..pdf: 1444579 bytes, checksum: 17272fc64c2d76578d08692395e65bfe (MD5) / Made available in DSpace on 2018-04-24T16:05:47Z (GMT). No. of bitstreams: 1 DOUGLAS ALEXANDRE SARAIVA LEÃO - TESE PPGEP 2014..pdf: 1444579 bytes, checksum: 17272fc64c2d76578d08692395e65bfe (MD5) Previous issue date: 2014-08-29 / A matriz energética brasileira é uma das mais limpas do mundo e, atualmente, mais de 45% de toda energia consumida no país provém de fontes renováveis. O álcool é um combustível que já tem o seu lugar assegurado nessa matriz, diante disso, o etanol de segunda geração pode se tornar uma fonte de energia para o Brasil e o mundo. Uma planta promissora na produção de bioetanol é o sisal, pois possui 90 % de açúcares fermentáveis e 10 % a mais de celulose que a cana-de-açúcar, além disso, o Brasil é o maior produtor de sisal do mundo. O objetivo do trabalho foi caracterizar a fibra do sisal, quanto à concentração de açucares por CLAE e a composição físico-química e térmica por meio de métodos convencionais e das técnicas de DRX, TG, DSC e MEV; determinar as melhores condições para o pré-tratamento ácido seguido de básico e realizar a hidrólise ácida e enzimática. Além de fermentar o licor hidrolisado de maior concentração de glicose. Para avaliar o pré-tratamento e a hidrólise ácida, usou-se duas granulometrias 0,21 e 0,49 mm da fibra e verificou-se os efeitos da temperatura e concentração de ácido na produção da xilose e glicose, utilizando como ferramenta um planejamento experimental fatorial. Para avaliar a hidrólise enzimática, verificou-se, por meio da aplicação de um planejamento experimental fatorial, o efeito da carga enzimática e a razão massa seca de fibra de sisal e extrato enzimático. Foram usadas as enzimas comerciais Celluclast 1.5L da Novozyme e betaglicosidase da Proenzyme. O pré-tratamento ácido seguido de básico mostrou-se bastante eficiente em concentrar a celulose, pela retirada da hemicelulose e lignina, provocando um aumento da celulose de 54 para 83%. Evidenciou-se a cristalinidade da fibra de sisal, comprovada por Difração de Raios X, modificou-se a morfologia da fibra, verificada por Microscopia Eletrônica de Varredura, e, por meio da Termogravimetria e Calorimetria Exploratória Diferencial comprovou-se a degradação da hemicelulose e lignina. Com o material pré-tratado, o processo de hidrólise enzimática foi mais eficiente na sacarificação, não ocorrendo eficácia para a hidrólise ácida. A hidrólise ácida com o material sem prétratamento provocou a sacarificação da celulose, no entanto, os valores obtidos de glicose são menores do que os obtidos na hidrólise enzimática que foi de 39000 ± 2700 mg.L-1. O licor hidrolisado enzimaticamente foi usado para a produção de etanol por meio de fermentação submersa, utilizando S. cerevisiae (Y904), desta forma, obteve-se uma produção de etanol de 19,4 g.L-1 em 7,3 h de fermentação. O monitoramento da cinética fermentativa em reator de batelada permitiu a avaliação do consumo de glicose, produção de etanol e massa microbiana. Em nível laboratorial a taxa especifica máxima de crescimento foi de 0,3 h-1, 96% de rendimento e produtividade de 2,7 g. L-1.h-1. / The Brazilian energy matrix is one of the cleanest in the world and currently more than 45% of all energy consumed in the country comes from renewable sources. The alcohol is a fuel already has its place assured in the Brazilian energy matrix, therefor the second-generation ethanol can become a source of energy for Brazil and the world. A promising plant to produce bioethanol is the sisal because it has 90% of fermentable sugars and 10% more cellulose than sugar cane, in addition to Brazil is the world's largest sisal producer. The objective was to characterize the sisal fiber, as the concentration of sugars by HPLC and the physicochemical composition chemical and thermal by means of conventional methods and techniques XRD, TG, DSC and MEV; determine the best conditions for the pre-treatment followed by acid perform basic and acidic and enzymatic hydrolysis. In addition to ferment the hydrolyzate liquor higher concentration of glucose. To evaluate the pre-treating and the acid hydrolysis it was used two grain sizes 0.21 and 0.49 mm fiber and found the effects of temperature and the concentration of acid in the production of xylose and glucose using as a tool factorial design. To assess the enzymatic hydrolysis was verified by applying a factorial design, the load effect enzyme and the dry weight ratio of sisal fiber and enzyme extract. The were used commercial enzymes of Celluclast 1.5L and Novozyme beta-glucosidase proenzyme. The pretreatment followed basic acid proved to be very effective in concentrating cellulose, by removing the hemicellulose and lignin, resulting in an increase in cellulose from 54 to 83%. Revealed a crystallinity of sisal fiber, proven by X-ray diffraction, has changed the morphology of the fiber, verified by microscopy Scanning Electron, and by Thermogravimetry and Scanning Calorimetry Differential proved the degradation of hemicellulose and lignin. With the material pretreated the enzymatic hydrolysis process was more efficient in saccharification, not occurring efficiency for acid hydrolysis. Acid hydrolysis of the material without pretreatment caused saccharification of cellulose however the values obtained glucose are smaller than those obtained in the enzymatic hydrolysis was 39000 ± 2700 mg l-1. The enzymatically hydrolysed liquor was used to produce ethanol by through submerged fermentation using S. cerevisiae (Y904), this way was obtained an ethanol yield of 19.4 gL1 in 7.3h of fermentation. The monitoring fermentation kinetics in batch reactor allowed assessment of glucose uptake, ethanol and microbial mass. In laboratory level the maximum specific rate growth was 0.3 h-1, 96% yield and productivity 2.7 g.L-1.h-1.

Thesis submitted in fulfilment of the requirements for the degree Magister Technologiae: Chemical Engineering in the Faculty of Engineering at the Cape Peninsula University of Technology 2014 / An awareness campaign on the harmful effects of Perfluorinated compounds (PFCs), especially Perfluorooctanoic acid (PFOA) and Perfluorooctane sulfonate (PFOS) has been conducted to inform the general public about the impact of these organic compounds on hu-mans and biota. These compounds have been shown to be potential carcinogens, as indi-cated by the United States Environmental Protection Agency (USEPA) and the Organization for Economic Co-operation and Development . A major concern about these chemicals is that they have been widely used in consumer products and have been detected in food and drinking water. They have been determined to be resistant to biological degradation, owing to their unique chemical and physical properties (fluorine atoms that have substituted hydrogen atoms in their chemical structure). Owing to their characteristics of being highly soluble in water, they cannot be removed from water using ordinary purification processes. Studies have been conducted to evaluate the removal of PFOA and PFOS from water using different methods. Among these methods, it has been proved that adsorption is a suitable method with the best adsorbent identified as activated carbon (AC). AC can be found in many forms, including as a fibre. The use of AC for the removal of PCFs can be augmented with sonica-tion and electro-chemical methods for rapid absorption of these compounds. The aim of this study was to remove these contaminants using a microporous AC fibre (ACF) made from an indigenous plant, Agave sisalana, which is widely available across sub-Saharan Africa, by using electro-physico-chemical methods. ACF has the following advantages when compared with granulated and/or powdered AC: it has a slightly larger reactive surface area; small quantities can be used; it is easily handled; it retains its shape under stress, thus does not require additional filtration to remove particulate residue; and can be regenerated easily. The manufacturing process of the ACF was done in several steps: 1) harvesting of the A. sisalana leaves, stripping them to obtain wet fibre by scrapping using traditional meth-ods, 2) chemical activation using NaOH, KOH, ZnCl2 and H3PO4, employing a spraying method instead of soaking, which was followed by drying, and 3) carbonisation in a furnace at the required temperature. The use of activation reagents involved the determination of an appropriate concentration, with optimum concentrations determined as 0.54M, 0.625M, 1.59M and 0.73M for NaOH, KOH, ZnCl2 and H3PO4, respectively. Apart from the fibre acti-vation, temperature and activation time were also important parameters that were optimised. A response surface methodology was used to design a set of experiments that provided the optimum temperature and activation time. From the input variables, the Expert design soft- ware generated experimental runs (n = 13) for each fibre activation reagent used with a tem-perature range of 450°C to 933°C being assessed for carbonisation time of between 17 to 208 minutes. ACF activated with KOH (0.54 M) and characterised by micropores with the highest surface area achieved being 1285.8 m2/g in comparison with Granular activated car-bon (Ounas et al., 2009) with an average surface area range of 1000 to 1100 m2/g. This sur-face area was measured using Dubinin-Astakhov isotherm with CO2 at 273 K. The physical characteristics of the ACF were analysed using a Scanning Electron Microscope to ascertain the integrity of the fibres. PFOA and PFOS were analysed using a solid phase extraction (SPE) method fol-lowed by analysis using a liquid chromatography/tandem mass spectrometer (SPE-LC/MS/MS). The water sample volume used for extraction was 60 mL. The instrument used was an HPLC - Ultimate 3000 Dionex HPLC system and MS model - Amazon SL Ion Trap, with the following MS/MS operational conditions and ion mode: MS Interface → ESI; dry temp → 350C; nebulising pressure → 60 psi; dry gas flow → 10 L/min; ionisation mode → negative; capillary voltage → +4500V; end plate offset → −500V, while the separation col-umn was a Waters Sunfire C18, 5 μm, 4.6 × 150 mm column (supplier: Waters, Dublin, Ire-land), with an operational temperature of 30C. Initially, adsorption studies (n = 48) using sonication (20 kHz) in batch systems indi-cated efficient removal of PFOA and PFOS within 120 min, with numerous samples (n = 14) achieving complete removal for both PFOA and PFOS. The minimum removal rates ob-served were 65.55% for PFOA and 95.92% for PFOS. From the ACF samples in which high-est removal rates were achieved, a number (n = 3) of the ACF samples were selected for surface characterisation. Based on the sonication in the previous experiments, an electro-physico-chemical adsorption regime was designed, to facilitate the rapid adsorption of PFOS and PFOA from contaminated drinking water in an electrolytic cell. In these experiments, si-multaneous sonication and electrolysis were used. A comparison was made between ACF produced in this study and the commercial activated carbon. The result revealed that adsorp-tion of PFOA and PFOS on ACF was a monolayer adsorption type phenomenon and had the best fit using a Freundlich isotherm compared with the Langmuir isotherm. Adsorption of PFOA and PFOS on the commercial AC presented a multilayer adsorption type of isotherm fit with the Langmuir isotherm having the best fit compared with the Freundlich isotherm.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-06-02T21:45:30Z No. of bitstreams: 1 StellaMariaAndradeGomesBarreto_DISSERT.pdf: 2589598 bytes, checksum: eb867f2ecba9f71b559518fcc2a0d571 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-06-07T20:58:36Z (GMT) No. of bitstreams: 1 StellaMariaAndradeGomesBarreto_DISSERT.pdf: 2589598 bytes, checksum: eb867f2ecba9f71b559518fcc2a0d571 (MD5) / Made available in DSpace on 2017-06-07T20:58:36Z (GMT). No. of bitstreams: 1 StellaMariaAndradeGomesBarreto_DISSERT.pdf: 2589598 bytes, checksum: eb867f2ecba9f71b559518fcc2a0d571 (MD5) Previous issue date: 2017-03-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / O beneficiamento das folhas de Agave sisalana fornece a fibra, com valor agregado para a ind?stria de sisal, e o restante do material vegetal, denominado de subproduto, que ? descartado, gera impacto ambiental. Diferentes aplica??es t?m sido atribu?das, no entanto, n?o existem pesquisas cient?ficas que apontem a utiliza??o deste subproduto como mat?ria-prima cosm?tica. O objetivo dessa pesquisa foi obter e caracterizar uma fra??o enriquecida em polissacar?deos (FrE) a partir do subproduto de Agave sisalana, avaliar a seguran?a in vitro e in vivo, bem como a atividade antioxidante in vitro, e, ent?o, desenvolver uma nanoemuls?o hidratante. A partir da por??o l?quida do subproduto foram obtidos o extrato bruto (EB) e duas fra??es. O EB e as fra??es foram avaliados quanto ? presen?a de a??cares, prote?nas e polifenois. A seguran?a foi avaliada por meio dos testes de citotoxicidade e fototoxicidade in vitro utilizando o m?todo colorim?trico do vermelho neutro. A irritabilidade prim?ria foi verificada pelo teste de contato (patch test). A capacidade antioxidante foi avaliada pelos m?todos de sequestro de DPPH e molibd?nio. Diferentes sistemas foram obtidos por meio de pseudodiagrama tern?rio, aditivados ou n?o com 0,5% de FrE. As formula??es selecionadas foram submetidas aos testes de estabilidade preliminar e acelerada por um per?odo de 90 dias. A efic?cia hidratante foi avaliada quanto ao conte?do h?drico do estrato c?rneo e quanto ? perda de ?gua transepidermal por um per?odo de 5 horas. As amostras apresentaram, como constituintes qu?micos, a??cares, polifenois e prote?nas. A FrE n?o apresentou potencial citot?xico ou fotot?xico, n?o foi irritante e pode ser considerada um ativo com propriedade antioxidante. Nanoemuls?es est?veis contendo 40% de fase oleosa, 10% de tensoativos e 50% de fase aquosa foram obtidas. A nanoemuls?o foi capaz de aumentar significativamente o conte?do h?drico e manter a fun??o de barreira da pele ap?s 5h de uma ?nica aplica??o. A fra??o obtida do subproduto industrial de Agave sisalana apresenta um perfil promissor como mat?ria-prima cosm?tica para cuidado da pele com capacidade antioxidante e hidratante, em conjunto com a possibilidade de agregar valor ao res?duo industrial, reduzindo os danos provocados ao meio ambiente pelo descarte desse material. / The processing of the leaves of Agave sisalana provides fiber, with added value for the sisal industry, and the rest of the plant material, known as by-product, is thrown and generates environmental impact. Different applications have been attributed, however, there are no scientific researches that aim to use this product as a cosmetic raw material. The objective of this research was to obtain and characterize polysaccharides-enriched fraction (FrE) from the Agave sisalana by-product of, assess the safety in vitro and in vivo, as well as to evaluate the antioxidant activity in vitro, and then to develop a nanoemulsion with moisturizer effect. From the liquid portion of the by-product obtained the crude extract (EB) and two fractions resulting from extractive process. The EB and the fractions were evaluated for the presence of sugars, proteins and polyphenols. Safety was evaluated by cytotoxicity and phototoxicity in vitro assays using the colorimetric method of Neutral Red. Irritability was evaluated by the primary contact test (patch test). The antioxidant capacity was assessed using the DPPH scavenging tests and molybdenum method. Different systems were obtained by means of pseduodiagrama ternary containing, or not, 0.5% FrE. The selected formulations were submitted to preliminary stability tests and accelerated in different temperatures conditions for a period of 90 days. The moisturizing efficacy was evaluated by water content of the stratum corneum and transepidermal water loss for a period of 5 hours. The samples presented as chemical constituents, sugars, polyphenols and proteins. The FrE showed no phototoxic potential or cytotoxic, and was not irritating to skin of volunteers and can be considered an asset with antioxidant property Nanoemulsion containing 40% oil phase, 50% aqueous phase and 10% surfactants was stable for 90 days.The nanoemulsion was able to significantly increase the water content and maintain skin barrier function after 5 hours from a single application. The fraction obtained from the industrial by-product of Agave sisalana demonstrated a promising profile as raw material for cosmetic skin care with moisturizing and antioxidant capacity, together with the possibility of adding value to industrial waste, reducing the damage caused to the environment by disposing of this material.

Submitted by Jean Medeiros (jeanletras@uepb.edu.br) on 2017-03-20T12:38:16Z No. of bitstreams: 1 PDF - Silmara Chaves de Souza.pdf: 14719856 bytes, checksum: 942ba44676fe8c8a24488354c5e17317 (MD5) / Approved for entry into archive by Secta BC (secta.csu.bc@uepb.edu.br) on 2017-03-22T15:19:52Z (GMT) No. of bitstreams: 1 PDF - Silmara Chaves de Souza.pdf: 14719856 bytes, checksum: 942ba44676fe8c8a24488354c5e17317 (MD5) / Made available in DSpace on 2017-03-22T15:19:52Z (GMT). No. of bitstreams: 1 PDF - Silmara Chaves de Souza.pdf: 14719856 bytes, checksum: 942ba44676fe8c8a24488354c5e17317 (MD5) Previous issue date: 2017-02-20 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Knowledge of the genetic diversity available in the sisal germplasm collection is essential for breeding programs, so it is imperative to obtain as much information as the characteristics related to the species. Morphoagronomic and molecular data when analyzed mainly together are determinants for studies of genetic divergence between accessions. The objective of this study was to evaluate the genetic divergence present in the Agave accessions of the Embrapa Cotton Germplasm Active Collection by means of morphoagronomic and molecular data. Thirty-seven Agave accessions were kept in the experimental field in Monteiro-PB and the following characteristics were evaluated: leaf number (NFO), plant height (ALT), leaf length (CFO), leaf weight , Dry weight (PFIF), dry fiber weight (PFIS), fiber length (CFI), presence of border spikes (PEB), tillering (PF) and resistance to folding (DR). Ten ISSR (Inter Sample Sequence Repeat) oligonucleotides were used for molecular analyzes. The data were interpreted as qualiquantitative for the morphoagronomic and qualitative binary characters for the molecular markers. The agronomic data were submitted to analysis of variance and the means comparison was done by the Scott-Knott test at 5% probability. The dissimilarity measurements were obtained by Gower distance for the morphoagronomic data and by the Jaccard coefficient for the molecular data. The sum of the matrices of dissimilarity of the morphoagronomic and molecular data was made; and the grouping was done by the hierarchical UPGMA method and Tocher optimization. The agronomic characteristics presented high genetic variability among the sisal accessions. IAC accesses were the ones that presented the least distance between them, indicating a possible narrow genetic base and high degree of kinship. Hybrids Kenya and RN as the most similar accesses and the access Tatuí 2 the most divergent, being indicated for possible crossings. The results obtained in this study will support the crop improvement program, which may allow the appearance of superior materials. / O conhecimento da diversidade genética disponível na coleção de germoplasma de sisal é fundamental para os programas de melhoramento, para tanto é imprescindível se obter o máximo de informações quanto às características relacionadas à espécie. Dados morfoagronômicos e moleculares quando analisados principalmente em conjunto são determinantes para estudos de divergência genética entre acessos. Objetivou-se, com este trabalho, avaliar a divergência genética presente nos acessos de Agave da Coleção Ativa de Germoplasma da Embrapa Algodão por meio de dados morfoagronômicos e moleculares. Trinta e sete acessos de Agave são mantidos no campo experimental em Monteiro-PB e foram avaliadas quanto as seguintes características: número de folhas (NFO), altura da planta (ALT), comprimento de folha (CFO), peso da folha (PFO), peso da mucilagem fresca (PMF), peso da mucilagem seca (PMS), peso da fibra fresca (PFIF), peso da fibra seca (PFIS), comprimento da fibra (CFI), presença de espinhos nas bordas (PEB), perfilhamento (PF) e resistência ao dobramento (RD). Dez oligonucleotídeos ISSR (Inter Sample Sequence Repeat) foram utilizados para as análises moleculares. Os dados foram interpretados como qualiquantitativos para os caracteres morfoagronômicos e qualitativos binários para os marcadores moleculares. Os dados agronômicos foram submetidos à análise de variância e a comparação de médias foi feita pelo teste de Scott-Knott a 5% de probabilidade. As medidas de dissimilaridade foram obtidas por meio da distância de Gower para os dados morfoagronômicos e pelo coeficiente de Jaccard para os dados moleculares. Foi feita a soma das matrizes de dissimilaridade dos dados morfoagronômicos e moleculares; e o agrupamento foi feito pelo método hierárquico UPGMA e de otimização de Tocher. As características agronômicas apresentaram elevada variabilidade genética entre os acessos de sisal. Os acessos IAC foram os que apresentaram menor distância entre si, indicando possível base genética estreita e alto grau de parentesco. Os Híbridos Quênia e RN como os acessos mais similares e o acesso Tatuí 2 o mais divergente, sendo indicados para possíveis cruzamentos. Os resultados obtidos neste estudo darão suporte ao programa de melhoramento da cultura, podendo possibilitar o aparecimento de materiais superiores.