Ultra-structural mapping of sugarcane bagasse after oxalic acid fiber expansion (OAFEX) and ethanol production by Candida shehatae and Saccharomyces cerevisiae

Background: Diminishing supplies of fossil fuels and oil spills are rousing to explore the alternative sources of energy that can be produced from non-food/feed-based substrates. Due to its abundance, sugarcane bagasse (SB) could be a model substrate for the second-generation biofuel cellulosic ethanol. However, the efficient bioconversion of SB remains a challenge for the commercial production of cellulosic ethanol. We hypothesized that oxalic-acid-mediated thermochemical pretreatment (OAFEX) would overcome the native recalcitrance of SB by enhancing the cellulase amenability toward the embedded cellulosic microfibrils. Results: OAFEX treatment revealed the solubilization of hemicellulose releasing sugars (12.56 g/l xylose and 1.85 g/l glucose), leaving cellulignin in an accessible form for enzymatic hydrolysis. The highest hydrolytic efficiency (66.51%) of cellulignin was achieved by enzymatic hydrolysis (Celluclast 1.5 L and Novozym 188). The ultrastructure characterization of SB using scanning electron microscopy (SEM), atomic force microscopy (AFM), Raman spectroscopy, Fourier transform-near infrared spectroscopy (FT-NIR), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) revealed structural differences before and after OAFEX treatment with enzymatic hydrolysis. Furthermore, fermentation mediated by C. shehatae UFMG HM52.2 and S. cerevisiae 174 showed fuel ethanol production from detoxified acid (3.2 g/l, yield 0.353 g/g; 0.52 g/l, yield, 0.246 g/g) and enzymatic hydrolysates (4.83 g/l, yield, 0.28 g/g; 6.6 g/l, yield 0.46 g/g). Conclusions: OAFEX treatment revealed marked hemicellulose degradation, improving the cellulases ability to access the cellulignin and release fermentable sugars from the pretreated substrate. The ultrastructure of SB after OAFEX and enzymatic hydrolysis of cellulignin established thorough insights at the molecular level. © 2013 Chandel et al; licensee BioMed Central Ltd.

The Brazilian sugar and alcohol sector: evolution, productive chain and innovations

Includes bibliography

The electro-oxidation of carbon monoxide and ethanol on supported Pt nanoparticles: The influence of the support and catalyst microstructure

The sluggish kinetics of ethanol oxidation on Pt-based electrodes is one of the major drawbacks to its use as a liquid fuel in direct ethanol fuel cells, and considerable efforts have been made to improve the reaction kinetics. Herein, we report an investigation on the effect of the Pt microstructure (well-dispersed versus agglomerated nanoparticles) and the catalyst support (carbon Vulcan, SnO2, and RuO2) on the rate of the electrochemical oxidation of ethanol and its major adsorbed intermediate, namely, carbon monoxide. By using several structural characterization techniques such as X-ray diffraction, X-ray absorption spectroscopy, and transmission electron microscopy, along with potentiodynamic and potentiostatic electrochemical experiments, we show that by altering both the Pt microstructure and the support, the rate of the electrochemical oxidation of ethanol can be improved up to a factor of 12 times compared to well-dispersed carbon-supported Pt nanoparticles. As a result of a combined effect, the interaction of Pt agglomerates with SnO2 yielded the highest current densities among all materials studied. The differences in the activity are discussed in terms of structural and electronic properties as well as by mass transport effects, providing valuable insights to the development of more active materials. © 2013 Springer-Verlag Berlin Heidelberg.

Melatonin and ethanol intake exert opposite effects on circulating estradiol and progesterone and differentially regulate sex steroid receptors in the ovaries, oviducts, and uteri of adult rats

Chronic ethanol intake is associated with sex hormone disturbances, and it is well known that melatonin plays a key role in regulating several reproductive processes. We report the effects of ethanol intake and melatonin treatment (at doses of 100. μg/100. g. BW/day) on sex hormones and steroid receptors in the ovaries, oviducts and uteri of ethanol-preferring rats. After 150 days of treatment, animals were euthanized, and tissue samples were harvested to evaluate androgen, estrogen, progesterone and melatonin receptor subunits (AR, ER-α and ER-β, PRA, PRB and MT1R, respectively). Melatonin decreased estradiol (E2) and increased progesterone (P4) and 6-sulfatoxymelatonin (6-STM), while an ethanol-melatonin combination reduced both P4 and E2. Ovarian AR was not influenced by either treatment, and oviduct AR was reduced after ethanol-melatonin combination. Oviduct ER-α, ER-β and uterine ER-β were down-regulated by either ethanol or melatonin. Conversely, ovarian PRA and PRB were positively regulated by ethanol and ethanol-melatonin combination, whereas PRA was down-regulated in the uterus and oviduct after ethanol consumption. MT1R was increased in ovaries and uteri of melatonin-treated rats. Ethanol and melatonin exert opposite effects on E2 and P4, and they differentially regulate the expression of sex steroid receptors in female reproductive tissues. © 2013 Elsevier Inc.

A formação de joint ventures como alternativa para investimentos no setor sucroalcooleiro brasileiro

Pós-graduação em Direito - FCHS

La bolsa de café, azúcar y cacao y su incidencia en las exportaciones de América Latina y el Caribe = The coffee, sugar and cocoa exchange and its impact on exports from Latin America and the Caribbean

Incluye Bibliografía

Aplicação de ferramentas do pensamento enxuto na redução de perdas na indústria sucroenergética: um estudo de caso

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Sugar markers in aerosol particles from an agro-industrial region in Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Multi-scale structural and chemical analysis of sugarcane bagasse in the process of sequential acid-base pretreatment and ethanol production by Scheffersomyces shehatae and Saccharomyces cerevisiae

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Seasonal variability of a conditional stability constant and the characterization of sedimentary humic substances from typical agricultural and urban areas

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

A Fuzzy Goal Programming model for solving aggregate production-planning problems under uncertainty: A case study in a Brazilian sugar mill

This paper proposes a Fuzzy Goal Programming model (FGP) for a real aggregate production-planning problem. To do so, an application was made in a Brazilian Sugar and Ethanol Milling Company. The FGP Model depicts the comprehensive production process of sugar, ethanol, molasses and derivatives, and considers the uncertainties involved in ethanol and sugar production. Decision-makings, related to the agricultural and logistics phases, were considered on a weekly-basis planning horizon to include the whole harvesting season and the periods between harvests. The research has provided interesting results about decisions in the agricultural stages of cutting, loading and transportation to sugarcane suppliers and, especially, in milling decisions, whose choice of production process includes storage and logistics distribution. (C)2014 Elsevier B.V. All rights reserved.

Endothelial AT(1) and AT(2) pathways in aortic responses to angiotensin II after stress and ethanol consumption in rats

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Organizational communication and innovation in micro and small companies: a study on the application of the Innovation Radar

This paper is a study on corporate communication and the ability to innovate in small businesses. The guiding question seeks to respond whether organizational communication is able to make progress and / or support innovation in micro and small companies, and the main objective is to analyze the relationship between innovation and organizational communication. It was applied the case study method and document research for interpreting a diagnosis instru- ment called “Innovation Radar” in a small business company located in the countryside of São Paulo state. The diagnosis is made based on assessment dimensions aimed at checking the maturity and the degree of innovation in micro and small companies. By evaluating these di- mensions it was possible to build analytical frameworks and highlight the influence of corporate communication in promoting innovation. The results indicate that every dimension of the “In- novation Radar” can improve their performance by means of corporate communication.

Análise estatística de parâmetros elétricos em usinas sucroalcoleiras do centro-oeste paulista

The industry of sugar cane has become an important contributor to the generation of electricity in Brazil. Currently there are 434 sugar and ethanol plants operating in the country, 23% of the total export electricity to the National Integrated System (SIN), the state of São Paulo has 182 plants and 30% of them export energy to the SIN. The objective of this study is to compare parameters of electrical efficiency in the sugar and alcohol industry. For the study, three plants localized in the midwest region of Sao Paulo state with great potential for production and exporting bioenergy were chosen. Five energy analyzers LANDYS + GYR SAGA were used for measure the electrical parameters. The variables studied were energy consumption (C) and power factor (PF). For the statistical analysis it was adopteda randomized block design in a factorial 3 5composed of three companies and five sectors of energy consumption,in which: reception(1), milling (2), boiler (3), supporting activities / juice treatment (4), and distillation (5), totaling 15 treatments. Each group comprised 192 repetitions (48 hours 4 measurements per hour). It was concluded that there is no interest for the plans to fix the FP and reach a value 0.92, which is considered the ideal power factor.This,because the plants generate their own energy and are not penalized. Regarding the energy consumed, all sectors had significant differences. When comparingsector to sector, the plant called USB showed no significant differences in sectors 1 and 3, and the plant USC, in sectors 1 and 4. Considering the production units of this sector and selling power this type of evaluation is essential to perform this analysis, since the analyzed sectors are most important in the production of sugar and ethanol, and analyze and monitor these parameters, use and consumption energy can provide a greater supply of energy to be commercialized.

The influence of different co-catalysts in Pt-based ternary and quaternary electro-catalysts on the electro-oxidation of methanol and ethanol in acid media

One of the key objectives in fuel cell technology is to reduce Pt loading by the improvement of its catalytic activity towards alcohol oxidation. Here, a sol-gel based method was used to prepare ternary and quaternary carbon supported nanoparticles by combining Pt-Ru with Mo, Ta, Pb, Rh or Ir, which were used as electro-catalysts for the methanol and ethanol oxidation reactions in acid medium. Structural characterization performed by XRD measurements revealed that crystalline structures with crystallites ranging from 2.8 to 4.1 nm in size and with different alloy degrees were produced. Tantalum and lead deposited as a heterogeneous mixture of oxides with different valences resulting in materials with complex structures. The catalysts activities were evaluated by cyclic voltammetry and by Tafel plots and the results showed that the activity towards methanol oxidation was highly dependent of the alloy degree, while for ethanol the presence of a metal capable to promote the break of C-C bond, such as Rh, was necessary for a good performance. Additionally, the catalysts containing of TaOx or PbOx resulted in the best materials due to different effects: the hi-functional mechanism promoted by TaOx and a better dispersion of the catalysts constituents promoted by PbOx. (C) 2012 Elsevier B.V. All rights reserved.