Berlin, Techn. Univ., Diss., 2003. / Computerdatei im Fernzugriff.

Berlin, Techn. Univ., Diss., 2003. / Computerdatei im Fernzugriff.

Face à la montée de la prise de conscience des enjeux écologiques actuels, la recherche se tourne vers le développement des bioprocédés pour développer de nouvelles solutions aux problèmes environnementaux. Cette thèse porte sur l’étude de la faisabilité d’un procédé de capture de CO2 à partir de la culture de la microalgue Chlorella vulgaris en photobioréacteur continu. Ce travail a permis d’identifier l’algue C. vulgaris comme une candidate prometteuse pour cette application. En effet C. vulgaris présente une capacité de production de biomasse et de fixation de CO2 très intéressante pour cette application. Les études menées lors de ce travail de thèse ont également permis de mettre à jour les interactions complexes entre les cellules algales et le CO2 présent à de fortes concentrations. De même, elles ont apporté un approfondissement à la compréhension des verrous existants pour le développement d’un procédé de captage du CO2 et de la nécessité de prendre en compte tous les paramètres de culture (lumière, concentration en nitrate). A partir des études menées, il a été possible de proposer un modèle pour la croissance de C. vulgaris en photobioréacteur continu. Bien que de futures études soient encore nécessaires pour être en mesure de parfaitement modéliser le comportement de l’algue lors de cultures en photobioréacteur, ce modèle présente une bonne corrélation avec les expérimentations. Enfin une étude de pré-dimensionnement a été proposée qui a permis de mettre en lumière les nombreux points d’interrogations encore existants avant d’être en mesure d’adapter le procédé de laboratoire à une échelle industrielle / Faced with the growing awareness of environmental issues, the research turns to the development of bioprocesses to develop new solutions to environmental problems. This thesis concerns the study of the feasibility of a process for CO2 capture from the culture of the microalgae Chlorella vulgaris in a continuous photobioreactor. This work has identified the algae C. vulgaris as a promising candidate for this application. Indeed C. vulgaris has a capacity of biomass production and CO2 biofixation very interesting for this application. Studies in this thesis allowed us to update the complex interactions between the algal cells and high CO2 concentrations. Also they have provided a deeper understanding of existing locks for the development of a process for CO2 capture and the need to take into account all the parameters of culture (light, nitrate concentration). A model for the growth of C. vulgaris in continuous photobioreactor has been proposed. This model shows good correlation with experiments; although future studies are still needed to be able to fully simulate the behaviour of algae in photobioreactor cultures. Finally a study of pre-design has been proposed allowing highlighting the many questions that still exist before being able to adapt the laboratory process to an industrial scale.

Techn. Universiẗat, Diss., 2003--Berlin.

Submitted by Milena Dias (milena.dias@ufpe.br) on 2015-03-11T18:49:15Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertaçao Páblo Eugênio da Costa e Silva.pdf: 1498936 bytes, checksum: 4eb542fe966b2a53e862d6b33ee0195d (MD5) / Made available in DSpace on 2015-03-11T18:49:15Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertaçao Páblo Eugênio da Costa e Silva.pdf: 1498936 bytes, checksum: 4eb542fe966b2a53e862d6b33ee0195d (MD5) Previous issue date: 2013 / CAPES / As doenças cardiovasculares são as principais causas de morte em todo o mundo e podem ser causadas pelo o acúmulo de fibrina nos vasos sanguíneos. Vários micro-organismos produtores de enzimas fibrinolíticas já são descritos na literatura, dentre eles bactérias e fungos. O objetivo do trabalho foi produzir enzimas fibrinolíticas a partir da microalga Chlorella vulgaris utilizando glicerol e milhocina, resíduo agroindustrial do processamento do milho, como fonte de carbono e nitrogênio, respectivamente. No cultivo utilizando 0,5 % de milhocina em meio Bold’ Basal (BBM) foi observado uma produção de 745 U mL-1 de enzima fibrinolítica pela microalga. Após a seleção do meio de cultura, foi realizado um delineamento estatístico utilizando Metodologia de Superfície de Resposta (RSM). A concentração celular foi otimizada, e o valor estimado pela equação foi de 1,52 g L-1, utilizando 0,9 % de glicerina e 1,2 % de milhocina. A produtividade celular, produção de protease e enzima fibrinolítica não conseguiram ser otimizadas, no entanto alcançaram níveis de 232 mg L-1 dia-1, 416 U mL-1 e 704 U mL-1, respectivamente. O presente trabalho mostrou que C. vulgaris cultivada em meio de cultura utilizando glicerol e o resíduo agroindustrial milhocina, pode ser viável para obter altos níveis de concentração de enzima fibrinolitica, bem como ser utilizada como um recurso no combate a doenças cardiovasculares.

La celulosa es un polisacárido que se encuentra presente en la naturaleza, el cual es de importancia mundial, debido a sus propiedades únicas que lo hacen fundamental en aplicaciones industriales tan diversas, como lo son en la producción del papel, en la industria biomédica, en el vestuario, cosméticos, entre otros. No sólo los organismos vegetales son capaces de producir celulosa, sino que también microorganismos como las bacterias Acetobacter, entre ellas la bacteria Gluconacetobacter xylinus (G. xylinus), la cual es el organismo más estudiado por el rendimiento de biopelícula producida, como también por la fuente de celulosa limpia obtenida sin necesidad de purificación. Sin embargo, este rendimiento varía según las condiciones en las que crece la bacteria, como lo son la fuente de glucosa utilizada y la oxigenación que necesita al ser un microorganismo aeróbico estricto. Se ha utilizado esta bacteria a nivel industrial de producción, no obstante, el alto costo de mantenimiento por las necesidades antes mencionadas, no ha logrado concretar el potencial que esta fuente entrega. Es por esto, que en el presente estudio se buscó una fuente natural de oxigenación, como lo es la microalga Chlorella vulgaris (C.vulgaris), la cual es de fácil manejo y económicamente rentable de mantener en laboratorio por sus amplios usos, como también su capacidad de producir oxigeno bajo luminosidad constante como fotoperiodo. Así es como en este trabajo de investigación se caracterizó el crecimiento de G. xylinus y C. vulgaris. Luego, se realizaron co-cultivos (CC) y cultivos separados (CS) entre ambos microorganismos. El objetivo de esta investigación fue estudiar la capacidad de optimizar la producción de celulosa bacteriana, entregando oxigenación controlada xv desde las microalgas fotosintéticamente activas (bajo fotoperiodo y luz constante) hacia el cultivo bacteriano. Nuestros resultados indican que, mediante la metodología de CS y bajo luminosidad constante al sexto día de cultivo estático, se produjo un rendimiento de celulosa bacteriana, dos veces mayor al producido por los controles, siendo el oxígeno producido por las microalgas esencial para esta producción. Estos resultados sugieren que sería más eficiente producir CS por sólo seis días que dejar cultivos por doce días estáticos, siendo factible producir más de dos cultivos para producir un mayor rendimiento que uno por más días. / Cellulose is a polysaccharide that is present in nature, which is of global importance, due to its unique properties that make it essential in industrial applications as diverse as in paper production in the biomedical industry, clothes, cosmetics, among others. Not only are plants capable of producing cellulose, but also microorganisms such as the bacteria Acetobacter, including the bacteria Gluconacetobacter xylinus (G. xylinus), which is the organism most studied for the biofilm yield produced, as well as by the source of clean cellulose obtained without purification. However, this yield varies depending on the conditions in which the bacteria grow, such as the source of glucose used and the oxygenation it needs as a strict aerobic microorganism. This bacteria has been used at the industrial production level, however, the high cost of maintenance because of the aforementioned needs, has failed to realize the potential that this source delivers.For this reason, in the present study, a natural source of oxygenation was sought, as is the microalga Chlorella vulgaris (C.vulgaris), which is easy to use and economically profitable to maintain in the laboratory for its wide uses, as well as its ability to produce oxygen under constant light as photoperiod. Therefore,the growth of G. xylinus and C. vulgaris was characterized in this research work, by performing co-cultures (CC) and separate cultures (CS) between both microorganisms. The objective of this research was to study the ability to optimize the production of bacterial cellulose, by delivering controlled oxygenation from photosynthetically active microalgae (under photoperiod and constant light) to the bacterial culture. xvii Our results indicate that, through the CS methodology and under constant luminosity at the sixth day of static cultivation, a yield of bacterial cellulose, was produced twice as high as that produced by the controls, the oxygen produced by the microalgae being essential for this production. These results suggest that it would be more efficient to produce CS for only six days than to leave cultures for twelve static days, being feasible to produce more than two cultures to produce a higher yield than one for more days. / Programa de Estímulo a la Excelencia Institucional (PEEI) de la Universidad de Chile

Seminario de Título entregado a la Universidad de Chile en cumplimiento parcial de los requisitos para optar al Título de Ingeniero en Biotecnología Molecular / La celulosa es un polisacárido que se encuentra presente en la naturaleza, el cual es de importancia mundial, debido a sus propiedades únicas que lo hacen fundamental en aplicaciones industriales tan diversas, como lo son en la producción del papel, en la industria biomédica, en el vestuario, cosméticos, entre otros. No sólo los organismos vegetales son capaces de producir celulosa, sino que también microorganismos como las bacterias Acetobacter, entre ellas la bacteria Gluconacetobacter xylinus (G. xylinus), la cual es el organismo más estudiado por el rendimiento de biopelícula producida, como también por la fuente de celulosa limpia obtenida sin necesidad de purificación. Sin embargo, este rendimiento varía según las condiciones en las que crece la bacteria, como lo son la fuente de glucosa utilizada y la oxigenación que necesita al ser un microorganismo aeróbico estricto. Se ha utilizado esta bacteria a nivel industrial de producción, no obstante, el alto costo de mantenimiento por las necesidades antes mencionadas, no ha logrado concretar el potencial que esta fuente entrega. Es por esto, que en el presente estudio se buscó una fuente natural de oxigenación, como lo es la microalga Chlorella vulgaris (C.vulgaris), la cual es de fácil manejo y económicamente rentable de mantener en laboratorio por sus amplios usos, como también su capacidad de producir oxigeno bajo luminosidad constante como fotoperiodo. Así es como en este trabajo de investigación se caracterizó el crecimiento de G. xylinus y C. vulgaris. Luego, se realizaron co-cultivos (CC) y cultivos separados (CS) entre ambos microorganismos. El objetivo de esta investigación fue estudiar la capacidad de optimizar la producción de celulosa bacteriana, entregando oxigenación controlada xv desde las microalgas fotosintéticamente activas (bajo fotoperiodo y luz constante) hacia el cultivo bacteriano. Nuestros resultados indican que, mediante la metodología de CS y bajo luminosidad constante al sexto día de cultivo estático, se produjo un rendimiento de celulosa bacteriana, dos veces mayor al producido por los controles, siendo el oxígeno producido por las microalgas esencial para esta producción. Estos resultados sugieren que sería más eficiente producir CS por sólo seis días que dejar cultivos por doce días estáticos, siendo factible producir más de dos cultivos para producir un mayor rendimiento que uno por más días. / Cellulose is a polysaccharide that is present in nature, which is of global importance, due to its unique properties that make it essential in industrial applications as diverse as in paper production in the biomedical industry, clothes, cosmetics, among others. Not only are plants capable of producing cellulose, but also microorganisms such as the bacteria Acetobacter, including the bacteria Gluconacetobacter xylinus (G. xylinus), which is the organism most studied for the biofilm yield produced, as well as by the source of clean cellulose obtained without purification. However, this yield varies depending on the conditions in which the bacteria grow, such as the source of glucose used and the oxygenation it needs as a strict aerobic microorganism. This bacteria has been used at the industrial production level, however, the high cost of maintenance because of the aforementioned needs, has failed to realize the potential that this source delivers.For this reason, in the present study, a natural source of oxygenation was sought, as is the microalga Chlorella vulgaris (C.vulgaris), which is easy to use and economically profitable to maintain in the laboratory for its wide uses, as well as its ability to produce oxygen under constant light as photoperiod. Therefore,the growth of G. xylinus and C. vulgaris was characterized in this research work, by performing co-cultures (CC) and separate cultures (CS) between both microorganisms. The objective of this research was to study the ability to optimize the production of bacterial cellulose, by delivering controlled oxygenation from photosynthetically active microalgae (under photoperiod and constant light) to the bacterial culture. xvii Our results indicate that, through the CS methodology and under constant luminosity at the sixth day of static cultivation, a yield of bacterial cellulose, was produced twice as high as that produced by the controls, the oxygen produced by the microalgae being essential for this production. These results suggest that it would be more efficient to produce CS for only six days than to leave cultures for twelve static days, being feasible to produce more than two cultures to produce a higher yield than one for more days. / Programa de Estímulo a la Excelencia Institucional (PEEI) de la Universidad de Chile

Microalgae are increasingly involved in the diet due to their beneficial effects on human health and therefore they are more often studied. Nowadays, there is a trend of using nanotechnology. The undesirable effects of copper oxide nanoparticles (CuO) attract more and more attention today. Since, there is an increasing demand for fossil fuels and simultaneously the amount of CO2 is increasing in the air, microalgae could serve in future as renewable fuels thanks to its rapid grow properties. In the diploma thesis, I dealt with the amount of carotenoid and polyphenolic substances in the algae Chlorella vulgaris after the influence of CuO nanoparticles. Experimental part of this work summarizes the results, revealing that CuO nanoparticles caused decrease of chlorophyle a by up to 60 % with CuO nanoparticles concetration of 25 mg/l, together with significant decrease of chlorophyle b and carotenoids. The amount of polyphenols and flavonoids in biomass has been changed only minimaly. In contrast, with usage of increasing concentration of CuO nanoparticles I found out by the SPOT test the increase of biomass in algae. Significant changes in selected secondary metabolites has been observed. The greatest statistically significant (p<0,01) growth with concetration 5 mg/l (1,08 ± 0,05 µg/g dry weight) has been observed for pOHbenzaldehyde, with increase by 42 % compared to control. In contrast rapid decrease has been noted with concentration 25 mg/l (0,06 ± 0,04 µg/g dry weight)

A produção de biocombustíveis a partir das microalgas vem se tornando promissora por ser uma fonte renovável, não poluente e por não competir com áreas de cultivo de alimentos. Devido à exaustão das fontes fósseis e à alta demanda por combustível de origem renovável e não poluente, as microalgas vêm despertando interesse nos cenários energético e ambiental. Por outro lado, existe um elevado custo no cultivo das mesmas, fazendo-se necessário estudos para desenvolvimento de novos reatores, meios de cultivos, técnicas de colheita, de extração de lipídios, transesterificação e também a implementação do conceito de biorrefinaria. Levando em conta o interesse crescente na utilização das microalgas como matéria prima na produção de biocombustíveis e a necessidade de estudos que torne o cultivo das microalgas em grande escala economicamente viável, esta pesquisa teve como objetivo determinar as melhores condições para o cultivo da microalga Chlorella vulgaris, buscando uma maior produtividade de biomassa e de lipídios. Os fatores avaliados foram: tempo de luminosidade, reciclo da biomassa após extração de lipídios e concentração de nutrientes (NaNO3, K2HPO4, KH2PO4 e glicerol) no meio de cultivo, em um arranjo ortogonal de Taguchi L8. De acordo com os resultados, identificou-se uma maior relevância, para a produtividade de biomassa, a utilização de glicerol e luminosidade (12 h), seguido do NaNO3 em alta concentração. A utilização de biomassa extraída mostrou-se inviável para o processo de cultivo, e a utilização de K2HPO4, KH2PO4 foram pouco influentes, porém essenciais. Paralelamente foi avaliado a viabilidade em se utilizar o efluente da Estação de Tratamento de Esgoto (ETE) da Escola de Engenharia de Lorena (EEL-USP) como meio de cultivo em um reator de PVC, construído para cultivo heterotrófico, no qual obteve-se uma alta produtividade de biomassa (0,20 g.L-1.d-1) e de lipídios (83,35 mg.L-1.d-1), se comparados a outros processos. / The production of biofuels from microalgae has become promising because it is a renewable, non-polluting source and because it does not compete with food growing areas. Due to the exhaustion of fossil fuel sources and the high demand of fuel from renewable and non-polluting origin, microalgae have been attracting interest in the energy and environmental scenarios. On the other hand, there is a high cost to cultivate microalgae, making necessary studies for the development of new reactors, culture media, harvesting techniques, lipid extraction, transesterification and also the implementation of the biorefinery concept. Taking the growing interest in the use of microalgae as a raw material in the production of biofuels and the need of studies to make large-scale microalgae cultivation economically viable, this research aimed to determination of the best conditions for the cultivation of microalga Chlorella vulgaris, seeking a higher productivity of biomass and lipids. The factors evaluated were: time of luminosity, biomass recycling after lipid extraction and nutrient concentration (NaNO3, K2HPO4, KH2PO4 and glycerol) in the culture medium using a orthogonal arrangement of Taguchi L8. According to the results, a greater relevance was identified for biomass productivity, the use of glycerol and luminosity (12 h), followed by NaNO3 in high concentration. The use of extracted biomass proved to be impractical for the process, and the use of K2HPO4, KH2PO4 was weak but essential. In parallel, the feasibility of using the effluent of the Effluent Treatment Plant (ETP) on Escola de Engenharia de Lorena (EEL-USP) as a culture medium for a PVC reactor, built for heterotrophic cultivation. It was obtained higger productivity of biomass (0.20 g.L-1.d-1) and lipids (83.35 mg.L-1.d-1) from it, if you compare to others process.

Submitted by Livia Mello (liviacmello@yahoo.com.br) on 2016-09-30T13:29:33Z No. of bitstreams: 1 TeseACMS.pdf: 2492159 bytes, checksum: 38dd2ebe8ceb091f79c747cd89c01233 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-10T19:00:10Z (GMT) No. of bitstreams: 1 TeseACMS.pdf: 2492159 bytes, checksum: 38dd2ebe8ceb091f79c747cd89c01233 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-10T19:00:21Z (GMT) No. of bitstreams: 1 TeseACMS.pdf: 2492159 bytes, checksum: 38dd2ebe8ceb091f79c747cd89c01233 (MD5) / Made available in DSpace on 2016-10-10T19:00:31Z (GMT). No. of bitstreams: 1 TeseACMS.pdf: 2492159 bytes, checksum: 38dd2ebe8ceb091f79c747cd89c01233 (MD5) Previous issue date: 2016-04-08 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / The effluent from the sugarcane (sugar and ethanol) industry known as vinasse presents high content of organic matter and nutrients that can be used in the cultivation of microalgae with the advantages of low cost and reuse of byproducts. This work proposes to investigate the best cultivation condition of Chlorella vulgaris (BEYERINCK, 1890) in agroecological vinasse treated and diluted in concentrations from 10% to 60%. It is noted that the vinasse carries microorganisms as bacteria and yeasts, and despite previous treatment of algal cultures, other microorganisms were always present. For algal growth, we initially tested different light sources (fluorescent, hot white LED and hot white with red LED). It was guaranteed the same light intensity (120μmols m 2s-1) for any of the vinasse concentrations. It was assessed the algal cell density, the pH and conductivity over 96 hours. The best result for growth of C. vulgaris was obtained in vinasse 20% in the presence of hot white and red LED with a growth rate (1.45 d-1), higher than the control (1.29 d-1). In a next step it was performed the microalgae cultivation in the best condition tested (20% vinasse) to evaluate the photosynthetic and biochemical parameters of biomass produced in addition to the physicochemical characterization of vinasse before and after cultivation. The results showed a reduction of the photosynthetic efficiency and chlorophyll concentration during the experimental period, suggesting mixotrophic metabolism possibly due to the presence of organic carbon. We observed that the biomass production was 40% higher in the vinasse in culture as compared to the control. The production of proteins and fatty acids was also higher in the biomass held in vinasse than in the control. The cultivation of the organisms led to a significant reduction of nitrogen levels (98%) and potassium (70%) in organic vinasse. This research has shown that microalgae cultivation in vinasse reduced the nutrient content of the residue, this factor has high impact when discarded in the environment and produced a biomass with high protein content and the presence of fatty acids that confer high commercial value, it can be investigated for the production of animal feed. The academic experience related to this study was also contributor of formal education in high school from a public school. / O efluente da indústria sucroalcooleira conhecido como vinhaça apresenta altos teores de matéria orgânica e nutrientes que podem ser utilizados no cultivo de microalgas com as vantagens de baixo custo e reaproveitamento de subprodutos. Este trabalho propõe investigar a melhor condição de cultivo de Chlorella vulgaris (BEYERINCK, 1890) em vinhaça orgânica tratada e diluída nas concentrações de 10 a 60%. Salienta-se que a vinhaça carrega consigo microrganismos como bactérias e leveduras e, apesar do tratamento prévio aos cultivos algais, os outros microrganismos estiveram sempre presentes. Para o crescimento algal, testamos incialmente diferentes fontes de luz (fluorescente, LED branco quente e LED branco quente com vermelho). Foi sempre garantida a mesma intensidade luminosa (120μmols m 2s-1) para todas as concentrações de vinhaça. Foi avaliada a densidade celular algal, o pH e a condutividade ao longo de 96 horas. O melhor resultado quanto ao crescimento de C. vulgaris foi obtido em vinhaça 20% na presença de LED branco quente e vermelho com taxa de crescimento (1,45 d -1), superior ao controle (1,29 d-1). Numa etapa seguinte foi realizado o cultivo microalgal na melhor condição testada (vinhaça 20%) para avaliação dos parâmetros fotossintéticos e bioquímicos da biomassa produzida, além da caracterização físico-química da vinhaça antes e após o cultivo. Os resultados mostraram redução da eficiência fotossintética e da concentração de clorofila a ao longo do período experimental, sugerindo metabolismo mixotrófico possivelmente decorrente da presença de carbono orgânico. Verificou-se que a produção de biomassa foi 40% maior no cultivo em vinhaça em comparação ao controle. A produção de proteínas e ácidos graxos também foi maior na biomassa mantida em vinhaça do que no controle. O cultivo dos organismos levou à redução significativa dos valores de nitrogênio (98%) e potássio (70%) na vinhaça orgânica. Esta pesquisa mostrou que o cultivo de microalgas em vinhaça reduziu o teor de nutrientes do resíduo, fator de grande impacto ao ser descartado no ambiente e produziu uma biomassa com alto teor de proteínas e presença de ácidos graxos que conferem elevado valor comercial, podendo ser investigada para produção de ração animal. A experiência acadêmica relativa a este estudo foi ainda contribuinte da educação formal no ensino médio de uma escola da rede pública.