1000 resultados para Penicillium chrysogenum. Planejamento experimental. CMCase. Avicelase. Xilanase. FPase
Resumo:
Drilling fluids have fundamental importance in the petroleum activities, since they are responsible for remove the cuttings, maintain pressure and well stability, preventing collapse and inflow of fluid into the rock formation and maintain lubrication and cooling the drill. There are basically three types of drilling fluids: water-based, non-aqueous and aerated based. The water-based drilling fluid is widely used because it is less aggressive to the environment and provide excellent stability and inhibition (when the water based drilling fluid is a inhibition fluid), among other qualities. Produced water is generated simultaneously with oil during production and has high concentrations of metals and contaminants, so its necessary to treat for disposal this water. The produced water from the fields of Urucu-AM and Riacho da forquilha-RN have high concentrations of contaminants, metals and salts such as calcium and magnesium, complicating their treatment and disposal. Thus, the objective was to analyze the use of synthetic produced water with similar characteristics of produced water from Urucu-AM and Riacho da Forquilha-RN for formulate a water-based drilling mud, noting the influence of varying the concentration of calcium and magnesium into filtered and rheology tests. We conducted a simple 32 factorial experimental design for statistical modeling of data. The results showed that the varying concentrations of calcium and magnesium did not influence the rheology of the fluid, where in the plastic viscosity, apparent viscosity and the initial and final gels does not varied significantly. For the filtrate tests, calcium concentration in a linear fashion influenced chloride concentration, where when we have a higher concentration of calcium we have a higher the concentration of chloride in the filtrate. For the Urucus produced water based fluids, volume of filtrate was observed that the calcium concentration influences quadratically, this means that high calcium concentrations interfere with the power of the inhibitors used in the formulation of the filtered fluid. For Riachos produced water based fluid, Calciums influences is linear for volume of filtrate. The magnesium concentration was significant only for chloride concentration in a quadratic way just for Urucus produced water based fluids. The mud with maximum concentration of magnesium (9,411g/L), but minimal concentration of calcium (0,733g/L) showed good results. Therefore, a maximum water produced by magnesium concentration of 9,411g/L and the maximum calcium concentration of 0,733g/L can be used for formulating water-based drilling fluids, providing appropriate properties for this kind of fluid.
Resumo:
Intelligent and functional Textile Materials have been widely developed and researched with the purpose of being used in several areas of science and technology. These fibrous materials require different chemical and physical properties to obtain a multifunctional material. With the advent of nanotechnology, the techniques developed, being used as essential tools to characterize these new materials qualitatively. Lately the application of micro and nanomaterials in textile substrates has been the objective of many studies, but many of these nanomaterials have not been optimized for their application, which has resulted in increased costs and environmental pollution, because there is still no satisfactory effluent treatment available for these nanomaterials. Soybean fiber has low adsorption for thermosensitive micro and nanocapsules due to their incompatibility of their surface charges. For this reason, in this work initially chitosan was synthesized to functionalise soybean fibres. Chitosan is a natural polyelectrolyte with a high density of positive charges, these fibres have negative charges as well as the micro/nanocpsules, for this reason the chitosan acts as auxiliary agent to cationize in order to fix the thermosensitive microcapsules in the textile substrate. Polyelectrolyte was characterized using particle size analyses and the measurement of zeta potential. For the morphological analysis scanning Electron Microscopy (SEM) and x-Ray Diffraction (XRD) and to study the thermal properties, thermogravimetric analysis (TGA), Differential Scanning Calorimetry (DSC), Near Infrared Spectroscopy analysis in the Region of the Fourier Transform Infrared (FTIR), colourimetry using UV-VIS spectrum were simultaneously performed on the substrate. From the measurement of zeta potential and in the determination of the particle size, stability of electrostatic chitosan was observed around 31.55mV and 291.0 nm respectively. The result obtained with (GD) for chitosan extracted from shrimp was 70 %, which according to the literature survey can be considered as chitosan. To optimize the dyeing process a statistical software, Design expert was used. The surface functionalisation of textile substrate with 2% chitosan showed the best result of K/S, being the parameter used for the experimental design, in which this showed the best response of dyeing absorbance in the range of 2.624. It was noted that soy knitting dyed with the thermosensitive micro andnanocapsules property showed excellent washing solidity, which was observed after 25 home washes, and significant K/S values.
Resumo:
On the basis of human evolution and the population increase was necessary, the emergence of new sources of energy, the development of new products and technologies. One such product, object of the industry revolution and of great importance to the development of humanity is the oil, a substance composed primarily of hydrocarbons which give rise to several other products as fuels, lubricants, polymers, solvents, cooking gas, asphalt for roads, fertilizers, medicines, paints, among other. However, mishandling this product may cause leaks and spills that generate huge damages to the environment and the economy. Soon, with the purpose of contributing to decrease is problematic, in this master's work was carried out an intensive search of the possible potential of the fibers of Ceiba pentandra (L.) "Kapok" and Calotropis Procera as bioadsorbents of petroleum in water. The choice of these fibers is due to surface properties such as oleophylics and hydrophobic, their buoyancy and yet, being biodegradable natural polymers derived from the Brazilian Northeast. This research was used experimental planning with response surface methodology (RSM) with the software Design Expert. The results were statistically efficient, obtaining a R2= 0.9995 for Calotropis Procera and a R2= 0.9993 for Kapok. And that, both fibers showed adsorption efficiency, removing more than 80% petroleum in water static and dynamic state.
Resumo:
The growing interest and applications of biotechnology products have increased the development of new processes for recovery and purification of proteins. The expanded bed adsorption (EBA) has emerged as a promising technique for this purpose. It combines into one operation the steps of clarification, concentration and purification of the target molecule. Hence, the method reduces the time and the cost of operation. In this context, this thesis aim was to evaluate the recovery and purification of 503 antigen of Leishmania i. chagasi expressed in E. coli M15 and endotoxin removal by EBA. In the first step of this study, batch experiments were carried out using two experimental designs to define the optimal adsorption and elution conditions of 503 antigen onto Streamline chelating resin. For adsorption assays, using expanded bed, it was used a column of 2.6 cm in diameter by 30.0 cm in height coupled to a peristaltic pump. In the second step of study, the removal of endotoxin during antigen recovery process was evaluated employing the non-ionic surfactant Triton X-114 in the washing step ALE. In the third step, we sought developing a mathematical model able to predict the 503 antigen breakthrough curves in expanded mode. The experimental design results to adsorption showed the pH 8.0 and the NaCl concentration of 2.4 M as the optimum adsorption condition. In the second design, the only significant factor for elution was the concentration of imidazole, which was taken at 600 mM. The adsorption isotherm of the 503 antigen showed a good fit to the Langmuir model (R = 0.98) and values for qmax (maximum adsorption capacity) and Kd (equilibrium constant) estimated were 1.95 mg/g and 0.34 mg/mL, respectively. Purification tests directly from unclarified feedstock showed a recovery of 59.2% of the target protein and a purification factor of 6.0. The addition of the non-ionic surfactant Triton X-114 to the washing step of EBA led to high levels (> 99%) of LPS removal initially present in the samples for all conditions tested. The mathematical model obtained to describe the 503 antigen breakthrough curves in Streamline Chelanting resin in expanded mode showed a good fit for both parameter estimation and validation steps. The validated model was used to optimize the efficiencies, achieving maximum values of the process and of the column efficiencies of 89.2% and 75.9%, respectively. Therefore, EBA is an efficient alternative for the recovery of the target protein and removal of endotoxin from an E. coli unclarified feedstock in just one step.
Resumo:
The use of plants for medicinal purposes is ancient, with widespread application in medicinal drugs. Although plants are promising sources for the discovery of new molecules of pharmacological interest, estimates show that only 17% of them have been studied for their possible use in medicine. Thus, biodiversity of Brazilian flora represents an immense potential for economic use by the pharmaceutical industry. The plant Arrabidaea chica, popularly known as pariri, is common in the Amazon region, and it is assigned several medicinal properties. The leaves of this plant are rich in anthocyanins, which are phenolic compounds with high antioxidant power. Antioxidant compounds play a vital role in the prevention of neurological and cardiovascular diseases, cancer and diabetes, among others. Within the anthocyanins found in Arrabidaea chica, stands out Carajurin (6,7-dihydroxy-5,4- dimethoxy-flavilium), which is the major pigment encountered in this plant. The present work aimed to study on supercritical extraction and conventional extraction (solid-liquid extraction) in leaves of Arrabidaea chica, evaluating the efficiency of the extractive processes, antioxidant activity and quantification of Carajurin contained in the extracts. Supercritical extraction used CO2 as solvent with addition of co-solvent (ethanol/water mixture) and were conducted by the dynamic method in a fixed bed extractor. The trials followed a 24-1 fractional factorial design, the dependent variables were: process yield, concentration of Carajurin and antioxidant activity; and independent variables were: pressure, temperature, concentration of co-solvent (v/v) and concentration of water in the co-solvent mixture (v/v). Yields (mass of dry extract/mass of raw material used) obtained from supercritical extraction ranged from 15.1% to 32%, and the best result was obtained at 250 bar and 40 C, co-solvent concentration equal to 30% and concentration of water in the co-solvent mixture equal to 50%. Through statistical analysis, it was found that the concentration of co-solvent revealed significant effect on the yield. Yields obtained from conventional extractions were of 8.1% (water) and 5.5% (ethanol). Through HPLC (High-performance liquid chromatography) analysis, Carajurin was quantified in all the extracts and concentration values (Carajurin mass/mass of dry extract) ranged between 1% and 2.21% for supercritical extraction. For conventional extraction, Carajurin was not detected in the aqueous extract, while the ethanol extract showed Carajurin content of 7.04%, and therefore, more selective in Carajurin than the supercritical extraction. Evaluation of antioxidant power (radical 2,2-diphenyl-1-picrylhydrazyl DPPH sequestration method) of the supercritical extracts resulted in EC50 values (effective concentration which neutralizes 50% of free radicals) ranged from 38.34 to 86.13 g/mL, while conventional extraction resulted in EC50 values of 167.34 (water) and 42.58 (ethanol) g/mL. As for the quantification of total phenolic content (Folin-Ciocalteau analysis) of the supercritical extracts resulted in values ranged from 48.93 and 88.62 mg GAE/g extract (GAE = Gallic Acid Equivalents), while solid-liquid extraction resulted in values of 37.63 (water) and 80.54 (ethanol) mg GAE/g extract. The good antioxidant activity cannot be attributed solely to the presence of Carajurin, but also the existence of other compounds and antioxidants in Arrabidaea chica. By optimizing the experimental design, it was possible to identify the experiment that presented the best result considering the four dependent variables together. This experiment was performed under the following conditions: pressure of 200 bar, temperature of 40 C, co-solvent concentration equal to 30% and concentration of water in the co-solvent mixture equal to 30%. It is concluded that, within the studied range, it is possible to purchase the optimum result using milder operating conditions, which implies lower costs and greater ease of operation.
Resumo:
Advanced Oxidation Processes (AOP) are techniques involving the formation of hydroxyl radical (HO) with high organic matter oxidation rate. These processes application in industry have been increasing due to their capacity of degrading recalcitrant substances that cannot be completely removed by traditional processes of effluent treatment. In the present work, phenol degrading by photo-Fenton process based on addition of H2O2, Fe2+ and luminous radiation was studied. An experimental design was developed to analyze the effect of phenol, H2O2 and Fe2+ concentration on the fraction of total organic carbon (TOC) degraded. The experiments were performed in a batch photochemical parabolic reactor with 1.5 L of capacity. Samples of the reactional medium were collected at different reaction times and analyzed in a TOC measurement instrument from Shimadzu (TOC-VWP). The results showed a negative effect of phenol concentration and a positive effect of the two other variables in the TOC degraded fraction. A statistical analysis of the experimental design showed that the hydrogen peroxide concentration was the most influent variable in the TOC degraded fraction at 45 minutes and generated a model with R = 0.82, which predicted the experimental data with low precision. The Visual Basic for Application (VBA) tool was used to generate a neural networks model and a photochemical database. The aforementioned model presented R = 0.96 and precisely predicted the response data used for testing. The results found indicate the possible application of the developed tool for industry, mainly for its simplicity, low cost and easy access to the program.
Resumo:
Advanced Oxidation Processes (AOP) are techniques involving the formation of hydroxyl radical (HO) with high organic matter oxidation rate. These processes application in industry have been increasing due to their capacity of degrading recalcitrant substances that cannot be completely removed by traditional processes of effluent treatment. In the present work, phenol degrading by photo-Fenton process based on addition of H2O2, Fe2+ and luminous radiation was studied. An experimental design was developed to analyze the effect of phenol, H2O2 and Fe2+ concentration on the fraction of total organic carbon (TOC) degraded. The experiments were performed in a batch photochemical parabolic reactor with 1.5 L of capacity. Samples of the reactional medium were collected at different reaction times and analyzed in a TOC measurement instrument from Shimadzu (TOC-VWP). The results showed a negative effect of phenol concentration and a positive effect of the two other variables in the TOC degraded fraction. A statistical analysis of the experimental design showed that the hydrogen peroxide concentration was the most influent variable in the TOC degraded fraction at 45 minutes and generated a model with R = 0.82, which predicted the experimental data with low precision. The Visual Basic for Application (VBA) tool was used to generate a neural networks model and a photochemical database. The aforementioned model presented R = 0.96 and precisely predicted the response data used for testing. The results found indicate the possible application of the developed tool for industry, mainly for its simplicity, low cost and easy access to the program.
Resumo:
Dissertao composta por 02 artigos.
Resumo:
Esta dissertao composta por 5 artigos.
Resumo:
Brazil has a great diversity of native fruits, which are not always widely consumed, being sold only in certain regions, due to their difficulty of post-harvest conservation. One such fruit is yellow guava, interesting source of nutrients. To promote the consumption and use of this fruit to the consumer public in different regions of the country, this study evaluated the incorporation of yellow Ya-cy ara in formulating a cereal bar. Therefore, fruits were evaluated for their chemical, physical and chemical characteristics and bioactive compounds in different stages of maturation yellow guava (green, mature and dried forms). The behavior of guava yellow front of to UV-C radiation was also evaluated. After these reviews, there was obtained yellow ripe guava flour after previous tests, was added to the base formulation cereal bar. For the experimental planning and development of the formulations was used factorial design 22 with a central point. The developed formulations were subjected to sensory evaluation using for treatment of multivariate data analysis (Principal Component Analysis- ACP). The preferred formulation in sensory evaluation was evaluated in their physical characteristics (texture), physical-chemical (moisture, ash, lipids, proteins, carbohydrates, dietary fiber and calorie), mineral content and fatty acid profile. The results indicated that the added yellow guava cereal bar developed in this study is one way to application and use of guava, increasing the consumption of fruit to different regions of the country, and can be considered a functional product, not only to contain the fruit in its composition, but also to present many beneficial nutrients that contribute to the health of consumers.
Resumo:
O presente trabalho teve como objetivo obter concentrados de cidos graxos mono e poliinsaturados a partir do leo branqueado de carpa (Cyprinus carpio), utilizando o mtodo de complexao com uria, e estabelecer as melhores condies atravs do estudo de seus parmetros. Foi utilizado um planejamento experimental 23 para determinar os fatores que influenciam de forma significativa (nvel de 95%) os experimentos da complexao com uria, e verificar quais as faixas de valores desses fatores que apresentam os melhores resultados. Os fatores de estudo foram: relao de uria-cido graxo (2:1 e 6:1), temperatura de cristalizao (4C e -12C) e tempo de cristalizao (14 e 24 h). As respostas para anlise estatstica foram: rendimento da frao lquida (%Rend), percentual de cidos graxos livres (%AGL) da frao lquida e o perfil de cidos graxos. Conforme o estudo realizado, a relao uria/AG se mostrou muito efetiva, de forma diretamente proporcional, na obteno de concentrados de cidos graxos monoinsaturados (AGMI) e poliinsaturados (AGPI). Pois, uma vez que ao aumentar a relao de uria/AG resultou em um meio favorvel para a incluso dos cidos graxos saturados (AGS) na cristalizao da uria. Por este motivo a relao (6:1) foi melhor para obter concentrados de AGMI+AGPI. A relao entre temperatura e rendimento de concentrados de cidos graxos insaturados foi de forma inversamente proporcional, sendo que no menor valor (-12C) ocorreu a melhor separao de cidos graxos saturados dos insaturados. O tempo foi significativo, porm com menor influncia quando comparado com as demais variveis de estudo. Devido a isso, o ganho em rendimento dos concentrados de cidos graxos insaturados em relao ao custo operacional envolvidos no mtodo de complexao com uria no sugere que o maior tempo seja utilizado, sendo que 14 h oferece rendimentos que tendem maior produtividade. Assim, as melhores condies para a obteno de concentrados foram: maior relao de uria/AG (6:1), menor temperatura (-12C) e menor tempo (14 h). Sendo que nestas condies as fraes lquidas apresentaram rendimento em massa de at 65,4%, e seu percentual de cidos graxos livres (%AGL) ficou em mdia 35,8 g/100g cido olico. Os cidos graxos mono e poliinsaturados na melhor condio de complexao com uria foram concentrados em 85,2%, e entre estes os EPA+DHA foram concentrados em 9,4%.
Resumo:
A modificao estrutural de leos e gorduras uma das principais reas de interesse de pesquisa em diferentes setores industriais. No caso da indstria de alimentos, a interesterificao empregada para melhorar propriedades nutricionais e funcionais, em que se obtm compostos diferentes dos que lhes deram origem. As lipases microbianas so os biocatalisadores mais utilizados industrialmente, por serem mais estveis, especficas e com propriedades bem mais diversificadas que as lipases de outras fontes. Este trabalho objetivou, primeiramente, a caracterizao da gordura da pele de frango (GPF) e sua comparao com leo de soja, como referncia, visando a utilizao de GPF em reaes de interesterificao. Para isto foram caracterizados quanto aos ndices de rancidez hidroltica e oxidativa, bem como de matria insaponificvel, ndices de saponificao, refrao e iodo. Foi realizado ainda o fracionamento e perfil de cidos graxos destes lipdios e suas fraes, com o clculo de seus ndices nutricionais. Foi verificado que a GPF apresentou qualidade satisfatria devido aos baixos ndices de acidez (0,65 g cido oleico.100 g -1 ), perxido (2,14 meq.kg-1 ), p-anisidina (0,70 unidades de absorvncia.g-1 ), alm de fonte de cidos graxos mono-insaturados (40%), sendo fonte promissora para estudos de interesterificao. Em um segundo momento o objetivo foi produzir lipdios modificados ricos em cidos graxos essenciais a partir da gordura da pele de frango e cidos graxos ramificados, utilizando lipase sn-1,3 especfica e interesterificao do tipo acidlise. Foram estudados os fatores concentrao de enzima, adio de gua, proporo de substratos e tempo, segundo um planejamento experimental fatorial completo 2 4 . As separaes analticas foram executadas em placas de cromatografia de camada delgada, sendo as fraes posteriormente extradas, ressuspensas e injetadas no cromatgrafo a gs. Foi verificado que a adio de gua ao meio reacional apresentou efeito significativo (p<0,05) para todos cidos graxos avaliados dos triacilgliceris, sendo que para o cido essencial linoleico (C18:2) o efeito do tempo de reao tambm foi significativo, sendo verificado que quanto maior o tempo de reao, menor a quantidade de gua a ser adicionada. Em um terceiro momento, o objetivo foi produzir ster fenlico a partir do DHCA, alm de realizar reaes de transesterificao deste ster com tricaprilina. Para a reao de transesterificao, foi utilizado um delineamento composto central rotacional (DCCR) variando a quantidade de enzima, tempo de reao e temperatura sobre a resposta (%) dos reagentes consumidos. A lipase Novozym 435 de Candida antarctica foi utilizada como catalisador de todas reaes. Foi verificado que a maior produo de ster (50%) ocorreu em oito dias. Nas reaes de transesterificao, as relaes molares em que houve maior consumo do ster produzido foram 1:5 e 1:10, sendo obtidos 21,1% e 29,6% de residual de dihidrocafeato de octila, respectivamente em 24 h. Foi observado que em altas temperaturas e tempo superior a 26 h, houve o menor residual de dihidrocafeato de octila (18,2%). Foram identificados trs diferentes compostos fenlicos, contendo em sua estrutura dihidrocafeato de octila e cido caprlico.
Resumo:
O desenvolvimento de filmes e coberturas um processo de transformao que utiliza polmeros capazes de formar uma matriz contnua. As protenas de pescado apresentam propriedades que so vantajosas no preparo de biofilmes, como habilidade para formar redes, plasticidade e elasticidade, apresentando boa barreira ao oxignio, mas sua barreira ao vapor de gua baixa devido sua natureza hidroflica. Estas propriedades podem ser melhoradas aplicando nanotecnologia, incluindo materiais como as nanoargilas. O objetivo do presente trabalho foi desenvolver filmes nanocompsitos a partir de biopolmeros proticos provenientes de isolados proticos de corvina (Micropogonias furnieri) e argilas organoflicas. O isolado protico de corvina (IPC) foi obtido utilizando processo de variao de pH para solubilizar e isolar protena. Os filmes polimricos foram desenvolvidos pela tcnica de casting. Para o desenvolvimento de filmes nanocompsitos de isolado protico de corvina (IPC) e montmorilonita foi executado um planejamento experimental de 3 nveis e 3 fatores com 3 rplicas no ponto central. Os resultados foram submetidos metodologia de superfcie de resposta (MSR) para estudar os efeitos simultneos das variveis independentes, concentrao de IPC (IPC = 2; 3,5 e 5 g/100 g de soluo filmognica); concentrao de montmorilonita (MMT = 0,3; 0,5 e 0,7 g/100 g de soluo filmognica); e plastificante glicerol (G = 25, 30 e 35 g/100 g de IPC em base seca) sobre as respostas resistncia trao (MPa), elongao (%), fora na ruptura (N), permeabilidade ao vapor de gua (g mm m-2 d -1 KPa-1 ) e solubilidade (%). O isolado protico obtido de carne mecanicamente separada de corvina apresentou 97,87% de protena (em base seca), boa capacidade de reteno de gua e solubilidade. Os valores de resistncia trao variaram entre 7,2 e 10,7 MPa e os valores de elongao de 39,6 a 45,8%. Os valores encontrados para PVA no presente trabalho encontram-se entre 3,2 e 5,5 g mm m-2 d -1 KPa-1 . Os filmes nanocompsitos produzidos a partir de IPC e MMT foram promissores, do ponto de vista das propriedades mecnicas, aparncia visual e fcil manuseio, bem como baixa permeabilidade ao vapor de gua e a baixa solubilidade. Com relao s propriedades mecnicas, a concentrao de IPC e MMT foi o principal fator que influenciou no desenvolvimento dos filmes nanocompsitos. O planejamento experimental utilizado determinou que 3,5 g de IPC; 0,5 g de MMT e 30 (g/100g de IPC) de glicerol seriam os parmetros ideais para desenvolvimento de filmes nanocompsitos utilizando a tcnica de casting. As coberturas de isolado protico de corvina (IPC) e as coberturas de IPC e MMT foram aplicadas em mamo minimamente processado para avaliar sua vida- til. O revestimento com cobertura de isolado protico de corvina e montmorilonita aplicado em mamo minimamente processado apresentou menor perda de massa 5,26%, menor crescimento microbiano e menor diminuio de firmeza, luminosidade e pH conseqentemente apresentou os melhores resultados na cobertura de mamo minimamente processado, quando comparados com a amostra controle sem cobertura.
Resumo:
Nesta tese foi demonstrado o potencial de produo de carboidratos por Aphanothece microscopica Ngeli cultivada no efluente oriundo de uma indstria de laticnios. Para tanto, o trabalho composto de quatro artigos que objetivaram avaliar a produo de carboidratos em funo da temperatura, inculo e razes C/N e N/P do elfluente, bem como a possibilidade de reso da gua residuria. Foram utilizadas temperaturas de (10, 20 e 30C) e inculo (100, 200 e 300 mg.L-1). A melhor condio indicada foi quando utilizou-se a temperatura de 30C e 200 mg.L-1 de inculo. Na sequncia, considerando a temperatura e a concentrao celular selecionada, foi estudada a influncia das razes C/N e N/P na produo de carboidratos. Para tal, C/N (20, 40 e 60) e N/P (5, 10 e 15) na produo de carboidratos extracelulares foram avaliadas em cultivos a 30C, tendo como inculo 200 mg.L-1. Os melhores resultados obtidos, foram quando foi utilizado C/N 60 e N/P 10. Uma vez definidas as melhores condies de produo de carboidratos, foi estudado o processo de separao de biomassa do meio de cultivo, a partir dos coagulantes FeCl3, Al2(SO4)3 e tanino. O efeito dos coagulantes na separao da biomassa foram estudados, quanto ao pH (6,0, 7,0 e 8,0) e concentrao de coagulantes (50, 300 e 550 mg.L-1), utilizando como parmetro de medida, a eficincia de remoo de DQO, turbidez e slidos suspensos (SS). Os resultados demonstraram que as concentraes de coagulantes influenciaram significativamente ao nvel de significncia de 5 %, na separao da biomassa, com eficincia significativa na remoo da DQO, turbidez e SS. A melhor condio avaliada foi a que utilizou tanino na concentrao de 300 mg.L-1 e pH 7,0, o que resultou em uma gua residuria com remoo mdia de 96 % da turbidez, com potencial de ser reutilizada. Por fim, foi realizada a identificao de carboidratos gerados por Aphanothece microscopica Ngeli. Os resultados evidenciaram uma biomassa com at 33,5 % de carboidratos totais, perfazendo uma frao de carboidratos extracelulares, na fase estacionria de crescimento celular, de aproximadamente 25 % e 8 % os carboidratos da parede celular. Ficou demonstrado ainda que a composio dos carboidratos extracelulares do microorganismo em estudo constitudo por mono e dissacardeos perfazendo concentraes na ordem de 12,88 % de glicose, 3,54 % de rafinose, 3,43 % sacarose, 2,13 % de frutose e 2,45 % de ribose. Ficou demonstrado o potencial de produo de carboidratos por Aphanothece microscopica Ngeli quando cultivada no efluente da indstria de laticnios.
Resumo:
Diante da grande quantidade de glicerol bruto gerado na sntese do biodiesel e seu baixo valor comercial, torna-se fundamental encontrar formas alternativas para converter este substrato em produtos com valor agregado. Neste contexto, este trabalho teve como objetivo avaliar diferentes leveduras oleaginosas capazes de metabolizar o glicerol bruto, gerado como coproduto na sntese de biodiesel, visando produzir biomassa como fonte de lipdios. Todos os cultivos foram realizados em frascos agitados, em condies estabelecidas de acordo com cada etapa do trabalho, sendo obtidos dados relativos ao crescimento celular e produo de lipdios, tratados estatisticamente conforme o propsito. Lipomyces lipofer NRRL Y-1155 apresentou diferenas significativas em relao s outras leveduras oriundas de banco de cultura, atingindo 57,64% de lipdios na biomassa. Estas leveduras apresentarem perfis de cidos graxos diferenciados, semelhantes aos dos principais leos vegetais utilizadas na sntese de biodiesel, com predominncia de cidos graxos poli-insaturados, especialmente cido linoleico (68,3% na levedura Rhodotorula glutinis NRRL YB-252). O cido gama-linolnico, um cido graxo essencial 6, foi detectado em todas as leveduras analisadas, sendo que na biomassa de Candida cylindracea NRRL Y-17506 chegou a 23,1%. Atravs de um planejamento experimental Plackett-Burman, verificou-se que as variveis concentrao de extrato de levedura e de MgSO4.7H20 demonstraram maior influncia na produo de lipdios por uma linhagem silvestre de Rhodotorula mucilaginosa. Para esta levedura, a partir da anlise de efeitos foi possvel estabelecer a seguinte condio para a produo de lipdios: 30,0 g.L-1 glicerol; 5,0 g.L-1 KH2PO4; 1,0 g.L-1 Na2HPO4; 3,0 g.L-1 MgSO4.7H2O; 1,2 g.L-1 extrato de levedura; pH inicial 4,5; temperatura 25C. Nestas condies conseguiu-se um teor de lipdios de 59,96% e lipdios totais produzidos de 5,51 g.L-1 . Tambm foi possvel observar aumento no teor de lipdios da biomassa ao longo do tempo de cultivo, bem como o aumento do teor relativo do cido linoleico, que atingiu 52%. Dentre as leveduras isoladas a partir de amostras ambientais do Extremo Sul do Brasil, a levedura identificada como Cryptococcus humicola se destacou das demais, apresentando proporo de 23,5% de cidos graxos saturados, 14,8% de cidos graxos monoinsaturados e 54,9% de cidos graxos poli-insaturados, destacando-se o cido linoleico. O planejamento Plackett-Burman foi tambm utilizado para esta levedura, sendo que as variveis concentrao de extrato de levedura e glicerol bruto demonstraram maior influncia na produo de lipdios. Posteriormente, um delineamento composto central rotacional (DCCR) foi proposto visando otimizao da produo de lipdios. Os modelos empricos preditivos obtidos para biomassa mxima e lipdios totais permitiram estabelecer para a produo de lipdios por Cryptococcus humicola a seguinte condio otimizada: 100,0 g.L-1 glicerol; 5,0 g.L-1 KH2PO4; 1,0 g.L-1 Na2HPO4; 4,8 g.L-1 extrato de levedura; pH inicial 4,5; temperatura 25C. Esta condio representou um incremento de cerca de 2 vezes nos lipdios totais em relao melhor condio estabelecida pelo planejamento Plackett-Burmann e um acrscimo de cerca de 4,8 vezes em relao s condies testadas inicialmente, atingindo 37,61% de lipdios e 8,85 g.L-1 de lipdios totais. Deste modo, os propsitos de valorizao de um coproduto oriundo da sntese de biodiesel, bem como a produo de um leo com potencial para a produo de biodiesel, foram cumpridos.
