Bioprospecção de leveduras fermentadoras de xilose visando a produção de etanol a partir de bagaço de cana-de-açúcar

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Viabilidade econômica da venda de energia elétrica em cogeração sob condições de risco: um estudo de caso

The availability of the electrical energy, in sufficient quantities and in competitive prices is a crucial factor to the economic development. The trade-in of the excess electrical energy produced in a system of cogeneration can be seen as an alternative to the creation of an additional source of revenues for ethanol power plants sector, besides contributing to the complementation of the Brazilian electrical headquarter with renewable sources. The objective of this study was to evaluate the economic feasibility of the implementation of a cogeneration electrical central using the excess of sugar cane bagasse and selling the excess of electrical energy with prices of the market. An ethanol power plant located in the state of Sao Paulo was used to this study. It was used the case study methodology, evaluating the potential of the investment under the viewpoint of the Net Present Value (NPV), Payback and Internal Rate of Return (IRR), and complementing the results of the Accounting Results (AC). It was created three alternative scenarios to reflect the level of the risk of every studied situation: the most likely, an optimistic and a pessimistic, each one with its assumptions. The Monte Carlo Simulations was used to insert the elements of risk to each scenario. The results showed that the project is feasible in all NPV scenarios. And the Payback and IRR analysis confirmed these evidences. The valuation with the AR showed that the project is most risky at the pessimistic scenario, but is feasibly in the most likely and the optimistic scenarios. It was concluded that the project is economic viable. However, the economic viability shown in the results is based on the maintenance of the future prices on the levels of the historical prices used in the analysis.

Growth of Pleurotus ostreatus in culture media based on formulated straw or grass

Mycelial growth strains of POS 98/38, POS 09/100, POS 09/101, and POS 09/102 of Pleurotus ostreatus were evaluated in culture media with various compositions based on extracts of substrates formulated with sugar cane bagasse together with straws and grasses, and with or without nitrogen supplementation. The evaluation was performed during incubation regularly with a ruler graduated in millimeters until total colonization of the culture medium contained in Petri dishes. The statistical model explaining the kinetics of mycelial growth of mushroom strains of P. ostreatus as a deterministic component has an exponential Gompertz function. The results show that the culture medium with sugar cane straw and brizantha grass (supplemented) showed the highest rates of mycelial growth, regardless of strain used compared to wheat straw-based culture media with had the lowest velocities of growth, regardless of supplementation and strains studied.

Produção de conídios do fungo entomopatogênico Metarhizium anisopliae em diferentes condições de cultivo e em biorreator de bandeja

Pós-graduação em Microbiologia - IBILCE

Estimativa do potencial de acréscimo da oferta de energia no setor sucroalcooleiro paulista a partir de cogeração e gaseificação do bagaço de cana-de-açúcar com utilização de ciclo combinado

This work evaluates the existing potential in the state of Sao Paulo for the generation of electrical energy using the sugar cane bagasse as fuel. As the bagasse is a by-product of the sugarcane and alcohol industry and it is produced in large scale in the country, mainly in the state of Sao Paulo, it is important to develop researches that aim the best utilization of this input. In order to determine its potential, at first, a study was conducted considering the utilization of the cogeneration, which is a common practice in the plants of the sector. However, it was concluded that the cogeneration could provide a higher quantity of energy if more modern technologies and more efficient processes were used. Another study to estimate the potential considered a system of gasification of the sugar cane bagasse integrated with the combined cycle (BIG/GTCC). It was concluded that this technology can provide a considerable increase in the electrical supply. In this work it was also developed an energetic study based on real data from a plant located in the state of Sao Paulo. A thermodynamic analysis was done in the existing equipment of the cogeneration section of the plant. And another analysis was done considering the implementation of the BIG/GTCC technology to the cogeneration system. Comparing the results of both settings, it was concluded that the utilization of the sugar cane bagasse integrated to a combined cycle increased considerably the efficiency in the generation of electricity of the plant, increasing more than six times its production capacity of electrical energy

Produção de conídios do fungo entomopatogênico Metarhizium anisopliae em diferentes condições de cultivo e em biorreator de bandeja

Pós-graduação em Microbiologia - IBILCE

Estimativa do potencial de acréscimo da oferta de energia no setor sucroalcooleiro paulista a partir de cogeração e gaseificação do bagaço de cana-de-açúcar com utilização de ciclo combinado

This work evaluates the existing potential in the state of Sao Paulo for the generation of electrical energy using the sugar cane bagasse as fuel. As the bagasse is a by-product of the sugarcane and alcohol industry and it is produced in large scale in the country, mainly in the state of Sao Paulo, it is important to develop researches that aim the best utilization of this input. In order to determine its potential, at first, a study was conducted considering the utilization of the cogeneration, which is a common practice in the plants of the sector. However, it was concluded that the cogeneration could provide a higher quantity of energy if more modern technologies and more efficient processes were used. Another study to estimate the potential considered a system of gasification of the sugar cane bagasse integrated with the combined cycle (BIG/GTCC). It was concluded that this technology can provide a considerable increase in the electrical supply. In this work it was also developed an energetic study based on real data from a plant located in the state of Sao Paulo. A thermodynamic analysis was done in the existing equipment of the cogeneration section of the plant. And another analysis was done considering the implementation of the BIG/GTCC technology to the cogeneration system. Comparing the results of both settings, it was concluded that the utilization of the sugar cane bagasse integrated to a combined cycle increased considerably the efficiency in the generation of electricity of the plant, increasing more than six times its production capacity of electrical energy

Synthesis of Carbon Nanomaterials through Up-Cycling Agricultural and Municipal Solid Wastes

This work addresses the synthesis of carbon nanomaterials (CNMs) by up-cycling common solid wastes. These feedstocks could supersede the use of costly and often toxic or highly flammable chemicals, such as hydrocarbon gases, carbon monoxide, and hydrogen, which are commonly used as feedstocks in current nanomanufacturing processes for CNMs. Agricultural sugar cane bagasse and corn residues, scrap tire chips, and postconsumer polyethylene (PE) and polyethylene terephthalate (PET) bottle shreddings were either thermally treated by sole pyrolysis or by sequential pyrolysis and partial oxidation. The resulting gaseous carbon-bearing effluents were then channeled into a heated reactor. CNMs, including carbon nanotubes, were catalytically synthesized therein on stainless steel meshes. This work revealed that the structure of the resulting CNMs is determined by the feedstock type, through the disparate mixtures of carbon-bearing gases generated when different feedstocks are pyrolyzed. CNM characterization was conducted by scanning and transmission electron microscopy as well as by Raman spectroscopy and by thermogravimetric analysis. Gas chromatography was used to characterize the gases in the synthesis chamber. This work demonstrated an alternative method for efficient manufacturing of CNMs using both biodegradable and nonbiodegradable agricultural and municipal carbonaceous wastes.

Materials prepared from biopolyethylene and curaua fibers: Composites from biomass

Composites of high-density biopolyethylene (HDBPE) obtained from ethylene derived from sugarcane ethanol and curaua fibers were formed by first mixing in an internal mixer followed by thermopressing. Additionally, hydroxyl-terminated polybutadiene (LHPB), which is usually used as an impact modifier, was mainly used in this study as a compatibilizer agent. The fibers, HDBPE and LHPB were also compounded using an inter-meshing twin-screw extruder and, subsequently, injection molded. The presence of the curaua fibers enhanced some of the properties of the HDBPE, such as its flexural strength and storage modulus. SEM images showed that the addition of LHPB improved the adhesion of the fiber/matrix at the interface, which increased the impact strength of the composite. The higher shear experienced during processing probably led to a more homogeneous distribution of fibers, making the composite that was prepared through extruder/injection molding more resistant to impact than the composite processed by the internal mixer/thermopressing. (c) 2012 Elsevier Ltd. All rights reserved.

Response surface methodology (RSM) to evaluate moisture effects on corn stover in recovering xylose by DEO hydrolysis

Response surface methodology (RSM), based on a 2(2) full factorial design, evaluated the moisture effects in recovering xylose by diethyloxalate (DEO) hydrolysis. Experiments were carried out in laboratory reactors (10 mL glass ampoules) containing corn stover (0.5 g) properly ground. The ampoules were kept at 160 degrees C for 90 min.(-) Both DEO concentration and corn stover moisture content were statistically significant at 99% confidence level. The maximum xylose recovery by the response surface methodology was achieved employing both DEO concentration and corn stover moisture at near their highest levels area. We amplified this area by using an overlay plot as a graphical optimization using a response of xylose recovery more than 80%. The mathematical statistical model was validated by testing a specific condition in the satisfied overlay plot area. Experimentally, a maximum xylose recovery (81.2%) was achieved by using initial corn stover moisture of 60% and a DEO concentration of 4% w/w. The mathematical statistical model showed that xylose recovery increases during DEO corn stover acid hydrolysis as the corn stover moisture level increases. This observation could be important during the harvesting of corn before it is fully dried in the field. The corn stover moisture was an important variable to improve xylose recovery by DEO acid hydrolysis. (c) 2011 Elsevier Ltd. All rights reserved.

The capability of endophytic fungi for production of hemicellulases and related enzymes

Abstract Background There is an imperative necessity for alternative sources of energy able to reduce the world dependence of fossil oil. One of the most successful options is ethanol obtained mainly from sugarcane and corn fermentation. The foremost residue from sugarcane industry is the bagasse, a rich lignocellulosic raw material uses for the production of ethanol second generation (2G). New cellulolytic and hemicellulytic enzymes are needed, in order to optimize the degradation of bagasse and production of ethanol 2G. Results The ability to produce hemicellulases and related enzymes, suitable for lignocellulosic biomass deconstruction, was explored using 110 endophytic fungi and 9 fungi isolated from spoiled books in Brazil. Two initial selections were performed, one employing the esculin gel diffusion assay, and the other by culturing on agar plate media with beechwood xylan and liquor from the hydrothermal pretreatment of sugar cane bagasse. A total of 56 isolates were then grown at 29°C on steam-exploded delignified sugar cane bagasse (DEB) plus soybean bran (SB) (3:1), with measurement of the xylanase, pectinase, β-glucosidase, CMCase, and FPase activities. Twelve strains were selected, and their enzyme extracts were assessed using different substrates. Finally, the best six strains were grown under xylan and pectin, and several glycohydrolases activities were also assessed. These strains were identified morphologically and by sequencing the internal transcribed spacer (ITS) regions and the partial β-tubulin gene (BT2). The best six strains were identified as Aspergillus niger DR02, Trichoderma atroviride DR17 and DR19, Alternaria sp. DR45, Annulohypoxylon stigyum DR47 and Talaromyces wortmannii DR49. These strains produced glycohydrolases with different profiles, and production was highly influenced by the carbon sources in the media. Conclusions The selected endophytic fungi Aspergillus niger DR02, Trichoderma atroviride DR17 and DR19, Alternaria sp. DR45, Annulohypoxylon stigyum DR47 and Talaromyces wortmannii DR49 are excellent producers of hydrolytic enzymes to be used as part of blends to decompose sugarcane biomass at industrial level.

The capability of endophytic fungi for production of hemicellulases and related enzymes

Abstract BACKGROUND: There is an imperative necessity for alternative sources of energy able to reduce the world dependence of fossil oil. One of the most successful options is ethanol obtained mainly from sugarcane and corn fermentation. The foremost residue from sugarcane industry is the bagasse, a rich lignocellulosic raw material uses for the production of ethanol second generation (2G). New cellulolytic and hemicellulytic enzymes are needed, in order to optimize the degradation of bagasse and production of ethanol 2G. RESULTS: The ability to produce hemicellulases and related enzymes, suitable for lignocellulosic biomass deconstruction, was explored using 110 endophytic fungi and 9 fungi isolated from spoiled books in Brazil. Two initial selections were performed, one employing the esculin gel diffusion assay, and the other by culturing on agar plate media with beechwood xylan and liquor from the hydrothermal pretreatment of sugar cane bagasse. A total of 56 isolates were then grown at 29°C on steam-exploded delignified sugar cane bagasse (DEB) plus soybean bran (SB) (3:1), with measurement of the xylanase, pectinase, β-glucosidase, CMCase, and FPase activities. Twelve strains were selected, and their enzyme extracts were assessed using different substrates. Finally, the best six strains were grown under xylan and pectin, and several glycohydrolases activities were also assessed. These strains were identified morphologically and by sequencing the internal transcribed spacer (ITS) regions and the partial β-tubulin gene (BT2). The best six strains were identified as Aspergillus niger DR02, Trichoderma atroviride DR17 and DR19, Alternaria sp. DR45, Annulohypoxylon stigyum DR47 and Talaromyces wortmannii DR49. These strains produced glycohydrolases with different profiles, and production was highly influenced by the carbon sources in the media. CONCLUSIONS: The selected endophytic fungi Aspergillus niger DR02, Trichoderma atroviride DR17 and DR19, Alternaria sp. DR45, Annulohypoxylon stigyum DR47 and Talaromyces wortmannii DR49 are excellent producers of hydrolytic enzymes to be used as part of blends to decompose sugarcane biomass at industrial level.

Aproveitamento sustentável do bagaço de cana de açúcar para obtenção do acetato de celulose

The sustainable use of waste resulting from the agribusiness is currently the focus of research, especially the sugar cane bagasse (BCA), being the lignocellulosic waste produced in greater volume in the Brazilian agribusiness, where the residual biomass has been applied in production energy and bioproducts. In this paper, pulp was produced in high purity from the (BCA) by pulping soda / anthraquinone and subsequent conversion to cellulose acetate. Commercial cellulose Avicel was used for comparison. The obtained cellulose acetate was homogeneous acetylation reaction by modifying the variables, the reaction time in hours (8, 12, 16, 20 and 24) and temperature in ° C (25 and 50). FTIR spectra showed characteristic bands identical to cellulosic materials, demonstrating the efficiency of separation by pulping. The characterization of cellulose acetate was obtained and by infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TG / DTG / DSC), scanning electron microscopy (SEM) and determining the degree of substitution (DS ) for the cellulose acetate to confirm the acetylation. The optimal reaction time for obtaining diacetates and triacetates, at both temperatures were 20 and 24 h. Cellulose acetate produced BCA presented GS between 2.57 and 2.7 at 25 ° C and 50 ° C GS obtained were 2.66 and 2.84, indicating the actual conversion of cellulose BCA of di- and triacetates. Comparative mode, commercial cellulose Avicel GS showed 2.78 and 2.76 at 25 ° C and 2.77 to 2.75 at 50 ° C. Data were collected in time of 20 h and 24 h, respectively. The best result was for the synthesis of cellulose acetate obtained from the BCA GS 2.84 to 50 ° C and 24 hours, being classified as cellulose triacetate, which showed superior result to that produced with the commercial ethyl cellulose Avicel, demonstrating converting potential of cellulose derived from a lignocellulosic residue (BCA), low cost, prospects of commercial use of cellulose acetate

Obtenção de triacetato de celulose a partir do bagaço de cana-deaçúcar para revestimento de micropartículas de goma gelana e avaliação do seu perfil de liberação in vitro e da mucoadesão ex vivo

Oral route of administration is considered to be the most comfortable, safe and greater adaptation for patients. But, oral route presents some disadvantages such as drugs bioavailability and side effects on the stomach. Some technologies are studied to soften and/or resolve these problems, such as coating with polymeric films, which are able to protect the pharmaceutical form of the acid stomachic environment and to act in the drug release, and mucoadhesive systems, which allow the pharmaceutical form remains a greater time interval in the intestine, increasing the effectiveness of the drug. Cellulose triacetate (CTA) films were produced from cellulose extracted from sugar cane bagasse. The films were prepared with different morphologies (with and without water, acting as non-solvent) and concentrations (3, 6.5 and 10%) of CTA and characterized using scanning electron microscopy (SEM), water vapor permeability (WVP), puncture resistance (PR), enzymatic digestion (DE), and mucoadhesive force evaluation (MF). Microscopy showed the formation of symmetric and asymmetric morphologies. WVP data showed that more concentrated films have higher values for WVP; moreover, asymmetric films had higher values than symmetric films. PR measurements showed that symmetric membranes are more resistant than asymmetric ones. More concentrated films were also more puncture resistant, except for symmetric membranes with CTA concentrations of 6.5 and 10% that did not show significant differences. All of the films presented large mucoadhesive capacities independent of their morphology and CTA concentration. From the results of WVP and RP, a symmetric filme with 6.5% CTA showed better ability and mechanical resistance, therefore, was selected to serve as coating of gellan gum (GG) particles incorporating ketoprofen (KET), which was confirmed by SEM. The selected film presented low values in measurements of the swelling index (SI) and in a dissolution test (DT). TGA analysis showed that the CTA coating does not influence the thermal stability of the particles and there is no incompatibility evidence between CTA, GG and KET. Coated particles released 100% of the ketoprofen in 24 h, while uncoated particles released the same amount in 4 h. The results of this study highlight the potential of CTA in the development of new controlled oral delivery systems.