Levels of yeast and its by-products on pacu juveniles feeding

This study was conducted to evaluate the inclusion of two levels (2.5 e 5.0%) of dried yeast (Saccharomyces cerevisiae) and its by-products, disrupted yeast cells and yeast cell wall in diets for juveniles of pacu (Piaractus mesopotamicus). Production performance, body and plasmatic composition indexes were evaluated. Seven isoproteic (26% digestible protein) and isoenergetic (3.100 kcal digestible energy) diets were formulated containing increased levels of each ingredient. The diets were supplied for 86 days, "ad libitum". Yeast and by-products increase feed efficiency and protein use, when compared to the control diet. Carcass composition and plasmatic (glucose, cortisol, uric acid, urea and plasmatic protein) levels are not affected by the test ingredient supplementation.

Electrochemical behavior of parent and photodegradation products of some selected pesticides

Electrochemical behavior of pesticides is extensively studied, but little attention has been given to the study of their degradation products (by-products) by electrochemical methods. However, the degradation products of pesticides can be even more toxic then the parent products and such studies should be encouraged. Therefore, the objective of this work was to evaluate the electroactivity of by-products of imazaquin, methylparathion, bentazon and atrazine, generated by UV irradiation and measured using cyclic and differential pulse voltammetry and UV-visible absorption spectrophotometry. Results have shown that several by-products exhibit electroactivity, allowing, in some cases, the simultaneous determination of both parent and degradation products.

Meat Quality of Lambs Fed on Palm Kernel Meal, a By-product of Biodiesel Production

This study aimed to establish the optimum level of palm kernel meal in the diet of Santa Ines lambs based on the sensorial characteristics and fatty acid profile of the meat. We used 32 lambs with a starting age of 4 to 6 months and mean weight of 22 2.75 kg, kept in individual stalls. The animals were fed with Tifton-85 hay and a concentrate mixed with 0.0, 6.5, 13.0 or 19.5% of palm kernel meal based on the dry mass of the complete diet. These levels formed the treatments. Confinement lasted 80 days and on the last day the animals were fasted and slaughtered. After slaughter, carcasses were weighed and sectioned longitudinally, along the median line, into two antimeres. Half-carcasses were then sliced between the 12th and 13th ribs to collect the loin (longissimus dorsi), which was used to determine the sensorial characteristics and fatty acid profile of the meat. For sensorial evaluation, samples of meat were given to 54 judges who evaluated the tenderness, juiciness, appearance, aroma and flavor of the meat using a hedonic scale. Fatty acids were determined by gas chromatography. The addition of palm kernel meal to the diet had no effect on the sensorial characteristics of meat juiciness, appearance, aroma or flavor. However, tenderness showed a quadratic relationship with the addition of the meal to the diet. The concentration of fatty acids C12:0, C14:0 and C16:0 increased with the addition of palm kernel meal, as did the sum of medium-chain fatty acids and the atherogenicity index. Up to of 19.5% of the diet of Santa Ines lambs can be made up of palm kernel meal without causing significant changes in sensorial characteristics. However, the fatty acid profile of the meat was altered.

Antioxidant capacity of the striped sunflower (Helianthus annuus L.) seed extracts evaluated by three in vitro methods

The antioxidant capacity of the striped sunflower seed cotyledon extracts, obtained by sequential extraction with different polarities of solvents, was evaluated by three different in vitro methods: ferric reducing/antioxidant power (FRAP), 2.2-diphenyl-1-picrylhydrazyl radical (DPPH) and oxygen radical absorbance capacity (ORAC) assays. In the three methods, the aqueous extract at 30 mu g/ml showed a higher antioxidant capacity value (FRAP, 45.27 mu mol; DPPH, 50.18%; ORAC, 1.5 Trolox equivalents) than the ethanolic extract (FRAP, 32.17 mu mol; DPPH, 15.21%; ORAC, 0.50 Trolox equivalents). When compared with the synthetic antioxidant butylated hydroxyl toluene, the antioxidant capacity of the aqueous extract varied from 45% to 66%, according to the used method. The high antioxidant capacity observed for the aqueous extract of the studied sunflower seed suggests that the intake of this seed may prevent in vivo oxidative reactions responsible for the development of several diseases, such as cancer.

Ferrolysis induced soil transformation by natural drainage in Vertisols of sub-humid South India

In sub-humid South India, recent studies have shown that black soil areas (Vertisols and vertic Intergrades), located on flat valley bottoms, have been rejuvenated through the incision of streambeds, inducing changes in the pedoclimate and soil transformation. Joint pedological, geochemical and geophysical investigations were performed in order to better understand the ongoing processes and their contribution to the chemistry of local rivers. The seasonal rainfall causes cycles of oxidation and reduction in a perched watertable at the base of the black soil, while the reduced solutions are exported through a loamy sand network. This framework favours a ferrolysis process, which causes low base saturation and protonation of clay, leading to the weathering of 2:1 then 1:1 clay minerals. Maximum weathering conditions occur at the very end of the wet season, just before disappearance of the perched watertable. Therefore, the by-products of soil transformation are partially drained off and calcareous nodules, then further downslope, amorphous silica precipitate upon soil dehydration. The ferrolysed area is fringing the drainage system indicating that its development has been induced by the streambed incision. The distribution of (14)C ages of CaCO(3) nodules suggests that the ferrolysis process started during the late Holocene, only about 2 kyr B.P. at the studied site and about 5 kyr B.P. at the watershed outlet. The results of this study are applied to an assessment of the physical erosion rate (4.8x10(-3) m/kyr) since the recent reactivation of the erosion process. (C) 2010 Elsevier B.V. All rights reserved.

Removal of phenol in high salinity media by a hybrid process (activated sludge plus photocatalysis)

The degradation of phenol by a hybrid process (activated sludge + photocatalysis) in a high salinity medium (50 g L-1 of chloride) has been investigated. The sludge used from a municipal wastewater facility was adapted to the high salt concentrations prior to use. The photocatalytic conditions were optimized by means of a factorial experimental design. TiO2 P25 from Degussa was used as the photocatalyst. The initial phenol concentration was approximately 200 mg L-1 and complete removal of phenol and a mineralization degree above 98% were achieved within 25 h of treatment (24 h of biological treatment and I h of photocatalysis). From HPLC analyses, five hydroxylated intermediates formed during oxidation have been identified. The main ones were catechol and hydroquinone, followed by 1,2,4-benzenetriol, 2-hydroxy- 1,4-benzoquinone, and pyrogallol, in this order. No formation of organochlorine compounds was observed. Therefore, the proposed hybrid process showed itself to be suited to treat phenol in the presence of high contents of salt. (c) 2007 Elsevier B.V. All rights reserved.

Desempenho e rendimento de carcaça de frangos de corte alimentados com dietas contendo subprodutos do arroz formuladas com base nos conceitos de proteína bruta e ideal

Foi conduzido um experimento para avaliar a utilização de subprodutos do arroz em dietas formuladas com base nos conceitos de proteína bruta e ideal para frangos de corte de 1 a 42 dias de idade. Foram utilizados 720 pintos machos de 1 dia de idade da linhagem "Hybro", em delineamento inteiramente ao acaso, em esquema fatorial 3 × 2, composto de três dietas (sem subprodutos, farelo de arroz integral e quirera de arroz) e dois conceitos de formulação de rações (proteína bruta e ideal), totalizando seis tratamentos e quatro repetições de 30 aves. O ganho de peso, o consumo de ração e a conversão alimentar foram avaliados aos 21 e 42 dias e as características de carcaça aos 42 dias de idade. As aves alimentadas com dietas formuladas pelo conceito tradicional (baseado na proteína bruta) apresentaram melhor conversão alimentar e menor taxa de deposição de gordura abdominal.

Utilização de levedura íntegra e seus derivados em dietas para juvenis de tilápia do Nilo

Neste trabalho, avaliou-se a adição de células íntegras de levedura e seus derivados em dietas para juvenis de tilápia do Nilo. Foram utilizados 144 juvenis machos de tilápia (peso médio de 52,1g) distribuídos em 12 tanques de fibra de vidro (250L), em delineamento inteiramente casualizado, composto por quatro tratamentos e três repetições. Os peixes foram alimentados ad libitum, duas vezes ao dia durante 60 dias, com dietas isoproteicas (28% PB) e isocalóricas (2.900kcal de ED kg-1) contendo levedura íntegra de cana-de-açúcar (LI), levedura autolisada (LA) e parede celular (PC) adicionados na proporção de 25% da proteína bruta total, comparadas com uma dieta controle (CO), sem adição de levedura. Não foram observadas diferenças significativas para conversão alimentar aparente e taxa de eficiência protéica. No entanto, o ganho em peso foi melhor nos peixes alimentados com as dietas LA (114,70g) e PC (131,03g), assim como em relação à taxa de crescimento específico (LA=1,79 e PC=1,93%), à proteína bruta no ganho de peso (LA=14,45 e PC=15,62%) e ao conteúdo corporal proteico (LA=14,89 e PC=15,67g 100g-1). As frações, a parede celular e a levedura autolisada de cana-de-açúcar podem ser utilizadas em dietas para juvenis de tilápia.

Composição química, valores de energia metabolizável e aminoácidos digestíveis de subprodutos do arroz para frangos de corte

Dois experimentos foram conduzidos para determinar a composição química, os valores de energia e os coeficientes de digestibilidade dos aminoácidos, do farelo de arroz integral (FAI) e da quirera de arroz (QA). No primeiro estudo, foram utilizadas 144 aves, com 21 dias de idade, machos, linhagem Cobb, que tiveram suas excretas totalmente coletadas para determinação da energia metabolizável aparente (EMA) e energia metabolizável aparente corrigida (EMAn). O delineamento experimental foi inteiramente casualizado, com três tratamentos e seis repetições, com oito aves cada. No segundo experimento, foi utilizado o método de alimentação forçada para a determinação dos coeficientes de digestibilidade dos aminoácidos. O delineamento foi inteiramente casualizado, com dois alimentos e um jejum e seis repetições com um galo cada. Os valores de MS, PB, EE, FB, EMA e EMAn foram, respectivamente, para FAI: 88,6%; 11,8%; 15,3%; 10,2%; 2968kcal kg-1 e 2804kcal kg-1 e para QA: 93,5%; 9,1%; 0,73%; 0,45%; 3338kcal kg-1 e 3239kcal kg-1. Os valores médios encontrados dos coeficientes de digestibilidade de aminoácidos essenciais e não essenciais foram, respectivamente, de 75,9% e 73,9%, para FAI, e 77,9% e 76,5%, para QA. Embora tenham apresentado níveis inferiores de energia, FAI e a QA podem ser utilizados nas rações de aves em substituição ao milho, uma vez que tiveram níveis maiores de proteína bruta e aminoácidos digestíveis.

f t value of the 0(+)-> 0(+) beta(+) decay of (32)Ar: A measurement of isospin symmetry breaking in a superallowed decay

We determined the absolute branch of the T=2 superallowed decay of (32)Ar by detecting the beta(+)-delayed protons and gamma decays of the daughter state. We obtain b(SA)(beta)=(22.71 +/- 0.16)%, which represents the first determination of a proton branch to better than 1%. Using this branch along with the previously determined (32)Ar half-life and energy release, we determined ft=(1552 +/- 12) s for the superallowed decay. This ft value, together with the corrected Ft value extracted from previously known T=1 superallowed decays, yields a measurement of the isospin symmetry breaking correction in (32)Ar decay delta(exp)(C)=(2.1 +/- 0.8)%. This can be compared to a theoretical calculation delta(C)=(2.0 +/- 0.4)%. As by-products of this work, we determined the gamma and proton branches for the decay of the lowest T=2 state of (32)Cl, made a precise determination of the total proton branch and relative intensities of proton groups that leave (31)S in its first excited state and deduced an improved value for the (32)Cl mass.

Clarification of a wheat straw-derived medium with ion-exchange resins for xylitol crystallization

BACKGROUND: Xylitol bioproduction from lignocellulosic residues comprises hydrolysis of the hemicellulose, detoxification of the hydrolysate, bioconversion of the xylose, and recovery of xylitol from the fermented hydrolysate. There are relatively few reports on xylitol recovery from fermented media. In the present study, ion-exchange resins were used to clarify a fermented wheat straw hemicellulosic hydrolysate, which was then vacuum-concentrated and submitted to cooling in the presence of ethanol for xylitol crystallization. RESULTS: Sequential adsorption into two anion-exchange resins (A-860S and A-500PS) promoted considerable reductions in the content of soluble by-products (up to 97.5%) and in medium coloration (99.5%). Vacuum concentration led to a dark-colored viscous solution that inhibited xylitol crystallization. This inhibition could be overcome by mixing the concentrated medium with a commercial xylitol solution. Such a strategy led to xylitol crystals with up to 95.9% purity. The crystallization yield (43.5%) was close to that observed when using commercial xylitol solution (51.4%). CONCLUSION: The experimental data demonstrate the feasibility of using ion-exchange resins followed by cooling in the presence of ethanol as a strategy to promote the fast recovery and purification of xylitol from hemicellulose-derived fermentation media. (c) 2008 Society of Chemical Industry.

Composites from Brazilian natural fibers with polypropylene: mechanical and thermal properties

Brazil has a well established ethanol production program based on sugarcane. Sugarcane bagasse and straw are the main by-products that may be used as reinforcement in natural fiber composites. Current work evaluated the influence of fiber insertion within a polypropylene (PP) matrix by tensile, TGA and DSC measurements. Thus, the mechanical properties, weight loss, degradation, melting and crystallization temperatures, heat of melting and crystallization and percentage of crystallinity were attained. Fiber insertion in the matrix improved the tensile modulus and changed the thermal stability of composites (intermediary between neat fibers and PP). The incorporation of natural fibers in PP promoted also apparent T(c) and Delta H(c) increases. As a Conclusion, the fibers added to polypropylene increased the nucleating ability, accelerating the crystallization process, improving the mechanical properties and consequently the fiber/matrix interaction.

Chemoenzymatic synthesis: a strategy to obtain xylitol monoesters

BACKGROUND: Fatty acid sugar esters are used as non-ionic surfactants in cosmetics, foodstuffs and pharmaceuticals. In particular, monoesters of xylitol have attracted industrial interest due to their outstanding biological activities. In this work, xylitol monoesters were obtained by chemoenzymatic synthesis, in which, first, xylitol was made soluble in organic solvent by chemo-protecting reaction, followed by enzymatic esterification reaction using different acyl donors. A commercial immobilized Candida antartica lipase was used as catalyst, and reactions with pure xylitol were carried out to generate data for comparison. RESULTS: t-BuOH was found to be the most suitable solvent to carry out esterification reactions with both pure and protected xylitol. The highest yields were obtained for reactions carried out with pure xylitol, but in this case by-products, such as di- and tri-esters isomers were formed, which required a multi-step purification process. For the systems with protected xylitol, conversions of 86%, 58% and 24% were achieved using oleic, lauric and butyric acids, respectively. The structures of the monoesters were confirmed by (13)C- and (1)H-NMR and microanalysis. CONCLUSION: The chemoenzymatic synthesis of xylitol monoesters avoided laborious downstream processing when compared with reactions performed with pure xylitol. Monoesters production from protected xylitol was shown to be a practical, economical, and clean route for this process, allowing a simple separation, because there are no other products formed besides xylitol monoesters and residual xylitol. (C) 2009 Society of Chemical Industry

Lifecycle assessment of fuel ethanol from sugarcane in Brazil

This paper presents the lifecycle assessment (LCA) of fuel ethanol, as 100% of the vehicle fuel, from sugarcane in Brazil. The functional unit is 10,000 km run in an urban area by a car with a 1,600-cm(3) engine running on fuel hydrated ethanol, and the resulting reference flow is 1,000 kg of ethanol. The product system includes agricultural and industrial activities, distribution, cogeneration of electricity and steam, ethanol use during car driving, and industrial by-products recycling to irrigate sugarcane fields. The use of sugarcane by the ethanol agribusiness is one of the foremost financial resources for the economy of the Brazilian rural area, which occupies extensive areas and provides far-reaching potentials for renewable fuel production. But, there are environmental impacts during the fuel ethanol lifecycle, which this paper intents to analyze, including addressing the main activities responsible for such impacts and indicating some suggestions to minimize the impacts. This study is classified as an applied quantitative research, and the technical procedure to achieve the exploratory goal is based on bibliographic revision, documental research, primary data collection, and study cases at sugarcane farms and fuel ethanol industries in the northeast of SA o pound Paulo State, Brazil. The methodological structure for this LCA study is in agreement with the International Standardization Organization, and the method used is the Environmental Design of Industrial Products. The lifecycle impact assessment (LCIA) covers the following emission-related impact categories: global warming, ozone formation, acidification, nutrient enrichment, ecotoxicity, and human toxicity. The results of the fuel ethanol LCI demonstrate that even though alcohol is considered a renewable fuel because it comes from biomass (sugarcane), it uses a high quantity and diversity of nonrenewable resources over its lifecycle. The input of renewable resources is also high mainly because of the water consumption in the industrial phases, due to the sugarcane washing process. During the lifecycle of alcohol, there is a surplus of electric energy due to the cogeneration activity. Another focus point is the quantity of emissions to the atmosphere and the diversity of the substances emitted. Harvesting is the unit process that contributes most to global warming. For photochemical ozone formation, harvesting is also the activity with the strongest contributions due to the burning in harvesting and the emissions from using diesel fuel. The acidification impact potential is mostly due to the NOx emitted by the combustion of ethanol during use, on account of the sulfuric acid use in the industrial process and because of the NOx emitted by the burning in harvesting. The main consequence of the intensive use of fertilizers to the field is the high nutrient enrichment impact potential associated with this activity. The main contributions to the ecotoxicity impact potential come from chemical applications during crop growth. The activity that presents the highest impact potential for human toxicity (HT) via air and via soil is harvesting. Via water, HT potential is high in harvesting due to lubricant use on the machines. The normalization results indicate that nutrient enrichment, acidification, and human toxicity via air and via water are the most significant impact potentials for the lifecycle of fuel ethanol. The fuel ethanol lifecycle contributes negatively to all the impact potentials analyzed: global warming, ozone formation, acidification, nutrient enrichment, ecotoxicity, and human toxicity. Concerning energy consumption, it consumes less energy than its own production largely because of the electricity cogeneration system, but this process is highly dependent on water. The main causes for the biggest impact potential indicated by the normalization is the nutrient application, the burning in harvesting and the use of diesel fuel. The recommendations for the ethanol lifecycle are: harvesting the sugarcane without burning; more environmentally benign agricultural practices; renewable fuel rather than diesel; not washing sugarcane and implementing water recycling systems during the industrial processing; and improving the system of gases emissions control during the use of ethanol in cars, mainly for NOx. Other studies on the fuel ethanol from sugarcane may analyze in more details the social aspects, the biodiversity, and the land use impact.

Supercritical steam cycles and biomass integrated gasification combined cycles for sugarcane mills

Back in 1970s and 1980s, cogeneration plants in sugarcane mills were primarily designed to consume all bagasse, and produce steam and electricity to the process. The plants used medium pressure steam boilers (21 bar and 300 degrees C) and backpressure steam turbines. Some plants needed also an additional fuel, as the boilers were very inefficient. In those times, sugarcane bagasse did not have an economic value, and it was considered a problem by most mills. During the 1990s and the beginning of the 2000s, sugarcane industry faced an open market perspective, thus, there was a great necessity to reduce costs in the production processes. In addition, the economic value of by-products (bagasse, molasses, etc.) increased, and there was a possibility of selling electricity to the grid. This new scenario led to a search for more advanced cogeneration systems, based mainly on higher steam parameters (40-80 bar and 400-500 degrees C). In the future, some authors suggest that biomass integrated gasification combined cycles are the best alternative to cogeneration plants in sugarcane mills. These systems might attain 35-40% efficiency for the power conversion. However, supercritical steam cycles might also attain these efficiency values, what makes them an alternative to gasification-based systems. This paper presents a comparative thermoeconomic study of these systems for sugarcane mills. The configurations studied are based on real systems that could be adapted to biomass use. Different steam consumptions in the process are considered, in order to better integrate these configurations in the mill. (C) 2009 Elsevier Ltd. All rights reserved.