Made available in DSpace on 2016-04-01T17:54:49Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-09-11. Added 1 bitstream(s) on 2016-04-01T18:00:30Z : No. of bitstreams: 1 000860213_20200911.pdf: 451488 bytes, checksum: 42a973a544500493638c49349249b14c (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A geração de álcool combustível a partir de resíduos lignocelulósicos pode ser uma fonte alternativa e renovável de energia. O Brasil é um dos maiores produtores de frutas tropicais do mundo, com destaque para a laranja e banana. Em consequência disto, é capaz de gerar grandes quantidades de resíduos que podem ser utilizados como biomassa que, uma vez hidrolisada, libera pentoses e hexoses. A fim de se buscar uma maior produção de etanol, a utilização de co-culturas que metabolizem tanto pentoses quanto hexoses torna-se bastante interessante. Dentro desse contexto, o objetivo do presente trabalho foi estudar o efeito da hidrólise de cascas de banana e laranja para a produção de etanol por co-culturas de Zymomonas mobilis e Pichia stipitis. A hidrólise ácida foi feita com ácido sulfúrico 5% e 15 min em autoclave, para a hidrólise enzimática utilizou-se kit fornecido pela Novozymes em reação a 50°C durante 36 h. Após as hidrólises o meio foi desintoxicado com carvão ativado. Foram avaliados os efeitos da fermentação somente por Z. mobilis e por co-culturas de Z. mobilis e P. stipitis, do pH, da agitação e da quantidade de açúcares no meio. As hidrólises ácida e enzimática liberaram 64,97 e 134,75 g/L de açúcares totais das cascas de banana e 101,30 e 176,70 g/L de açúcares totais das cascas de laranja, respectivamente. A desintoxicação do hidrolisado resultou em remoção de 58% a 93% dos fenóis e 1,7% a 4% dos açúcares totais. Nas fermentações descontínuas com meio sintético o maior crescimento celular e máxima produção de etanol foram 1,52 e 11,29 g/L para a monocultura de Z. mobilis, e 8,00 e 77,02 g/L para a co-cultura, respectivamente. Para o meio com cascas de banana essas respostas foram 1,87 e 4,16 g/L para a monocultura, e 15,19 e 23,92 g/L para a co-cultura, respectivamente. Para o meio com cascas de laranja, as mesmas respostas foram 0,39 e 1,85 g/L para a monocultura, e 6,73 e... / The generation of ethanol from lignocellulosic waste, such as fruit crops, can be an alternative and renewable energy source. Brazil is one of the largest producers of tropical fruits in the world, especially orange and banana. As a result, it is able to generate large amounts of waste that may be used as biomass, which once hydrolyzed, releases pentoses and hexoses. In order to get a higher ethanol yield, the use of co-cultures which metabolize both pentose and hexose becomes quite interesting. In this context, the objective of this work was to study the hydrolysis effect of banana and orange peels for ethanol production by co-cultures of Zymomonas mobilis and Pichia stipitis. The acid hydrolysis was performed with 5% sulfuric acid and 15 min in autoclave; for the enzymatic hydrolysis was used a commercial kit supplied by Novozymes, in reaction at 50°C for 36 h. After the hydrolysis the medium was detoxified with activated carbon. The effects of fermentation by Z. mobilis monoculture and Z. mobilis and P. stipitis co-cultures, pH, agitation and the initial amount of sugars in the middle were evaluated. The sequential acid and enzymatic hydrolysis released 64.97 and 134.75 g/L of total sugars from banana peels and 101.30 and 176.70 g/L of total sugars from orange peels, respectively. The detoxification of the hydrolysate resulted in a removal of 58% to 93% of phenol and 1.7% to 4% of the total sugars. In Erlenmeyer fermentations with synthetic medium, the largest cell growth and maximum ethanol production were 1.52 and 11.29 g/L for Z. mobilis monoculture, and 8.00 and 77.02 g/L for the co-culture, respectively. In the medium with banana peels, these responses were 1.87 and 4.16 g/L for monoculture, and 15.19 and 23.92 g/L for the co-culture, respectively. To the medium with orange peels, the same responses were 0.39 and 1.85 g/L for monoculture and 6.73 and 11.36 g/L for the co-culture, respectively. For all evaluated media, the Z. ...

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Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-19T13:34:45Z No. of bitstreams: 5 hil.pdf: 1837336 bytes, checksum: 915b40a5d9c4387507e76471c6ae2ca7 (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2110 bytes, checksum: b4c884761e4c6c296ab2179d378436d4 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-20T11:01:25Z (GMT) No. of bitstreams: 5 hil.pdf: 1837336 bytes, checksum: 915b40a5d9c4387507e76471c6ae2ca7 (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2110 bytes, checksum: b4c884761e4c6c296ab2179d378436d4 (MD5) / Made available in DSpace on 2015-02-20T11:01:25Z (GMT). No. of bitstreams: 5 hil.pdf: 1837336 bytes, checksum: 915b40a5d9c4387507e76471c6ae2ca7 (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2110 bytes, checksum: b4c884761e4c6c296ab2179d378436d4 (MD5) Previous issue date: 2013-02-20 / Funda??o de Amparo ? Pesquisa do estado de Minas Gerais (FAPEMIG) / Para a manuten??o das pr?ticas econ?micas e s?cio-culturais constru?das sobre a explora??o e transforma??o do petr?leo, faz-se necess?rio criar alternativas que n?o rompam de forma estanque com as pr?ticas industriais hoje vigentes. Nesse contexto, o uso de biomassas para a produ??o de combust?veis l?quidos que alimentem motores ? combust?o permite sustentar pr?ticas antigas com novos benef?cios. Dessa forma, a presente disserta??o teve por objetivo avaliar o potencial da torta de maca?ba, um coproduto da ind?stria de ?leos vegetais, como insumo para produ??o de bioetanol. Tal objetivo foi trabalhado atrav?s de estudos de sacarifica??o da torta de maca?ba com posterior processo fermentativo. A biomassa em quest?o foi caracterizada quimicamente, o que indicou a presen?a de aproximadamente 50% de carboidratos, distribu?dos em, 23,16 ? 0,95 % de amido, 11,49 ? 1,08% de celulose, 9,6 ? 0,79% de hemicelulose e 11,48 ? 0,62 % de a??cares sol?veis. Para a primeira interven??o da despolimeriza??o dos polissacar?deos presentes na torta de maca?ba foi realizado um planejamento experimental fatorial 25-1 com 5 fatores e 4 pontos centrais com as seguintes vari?veis: concentra??o de ?cido sulf?rico, tempo de pr?-tratamento ?cido, raz?o s?lido/l?quido, concentra??o de amiloglicosidase e concentra??o de celulase. Na sequ?ncia, o processo de sacarifica??o foi otimizado com o uso de delineamento composto central rotacional 23, com 3 fatores, 4 pontos centrais e 6 pontos axiais, onde foram avaliadas as concentra??es de ?cido sulf?rico, amiloglicosidase e celulase. Um hidrolisado obtido em condi??o otimizada com 92% de efici?ncia foi submetido ? destoxifica??o com carv?o ativado e, em seguida, foram realizados ensaios de fermentabilidade conduzidos como as leveduras Saccharomyces cerevisiae e Pichia stipitis. A levedura S. cerevisiae se mostrou resistente ao hidrolisado n?o destoxificado, apresentando YP/S de 0,49. P. stipitis mostrou-se suscept?vel ao meio n?o destoxificado, mas foi capaz de converter 99% dos a??cares redutores presentes no meio destoxificado. A torta de maca?ba apresentou potencial consider?vel para produ??o de bioetanol. A partir dos dados de bancada ? poss?vel estimar uma produ??o de 104l de etanol por tonelada de torta de maca?ba. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Qu?mica, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2011. / ABSTRACT For the maintenance of economic and socio-cultural practices built on the exploitation and processing of oil it is necessary to create alternatives that do not break so tight with current industrial practices. In this context, the use of biomass to produce liquid fuels that are fed into to combustion engines allows to sustain old practices with new benefits. Thus, this dissertation aimed to evaluate the potential of macaw palm coconut cake, a co-product of vegetable oil industry, as an input for bioethanol production. This goal was worked out through studies of the process of saccharification of macaw palm coconut cake with subsequent fermentation. The biomass in question was characterized chemically, what indicated the presence of approximately 50% of carbohydrates, among which, 23,16 ? 0,95% of starch, 11,49 ? 1,08% of cellulose, 9,6 ? 0,79% of hemicellulose and 11,48 ? 0,62% of soluble sugars. For the first intervention of deconstruction of the polysaccharides present in the macauba cake it was held a 25-1 factorial experimental design with five factors and four central points with the following variables: concentration of sulfuric acid, time of acid pretreatment, solid / liquid ratio, amyloglucosidase and cellulose concentrations. Following, the saccharification process was optimized using central composite rotational design 23, with three factors, four central points and six axial points, whereas the concentrations of sulfuric acid, cellulose and amyloglucosidase were evaluated. A hydrolyzed obtained in optimum condition with 92% efficiency was subjected to detoxification with activated charcoal and then, fermentability assays were carried out with yeasts Saccharomyces cerevisiae and Pichia stipitis. The yeast S. cerevisiae has proved resilient to the non-detoxified hydrolyzate and presented YP/S of 0.49. P. stipitis was found to be susceptible to the non-detoxified medium, but it was able to convert 99% of reducing sugars present in the detoxified medium. The macaw palm coconut cake showed considerable potential for bioethanol production. From the lab bench data it is possible to estimate a production of 104 l of ethanol per ton of macaw palm coconut cake.