999 resultados para Sugar Part
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The response to B in agricultural systems of sugar cane is still an unexplored issue; B application has however recently been widely publicized and used with a certain degree of frequency. The use of 10B-labeled fertilizers may further contribute to clarify this practice. With the objective of evaluating sugar cane use of B (10B) derived from fertilizer (boric acid), an experiment was conducted under field conditions in the 2005/2006 growing season. The experiment consisted of the installation of microplots (2 x 1.5 m) where 4 kg ha-1 B (boric acid with 85.95 % in 10B atoms) dissolved in water was applied 90 days after planting (May 2005). The solution was applied to the soil on both sides of the plant row at a distance of 20 cm. After harvest (June 2006) the B content and 10B abundance in % atoms in all parts of the sugar cane plants (stalks, dry leaves, tips and roots) were determined. Results showed that the total B accumulated was 471 g ha-1 in the entire plant (35 % in the stalks, 22 % in the dry leaves, 9 % in the tips and 34 % in the roots). The sugar cane plants used on average 14 % of the total accumulated B in the above-ground part (44 g ha-1) and 11 % in the roots (19 g ha-1), totaling 13 % in the entire plant (63 g ha-1). The recovery of 10B-fertilizer by sugar cane plants was low, around 2 % of the total applied amount.
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The recent identification of several additional members of the family of sugar transport facilitators (gene symbol SLC2A, protein symbol GLUT) has created a heterogeneous and, in part, confusing nomenclature. Therefore, this letter provides a summary of the family members and suggests a systematic nomenclature for SLC2A and GLUT symbols.
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Biocatalysis can be applied in organic synthetic chemistry to counter challenges posed by increased demands towards chemo-, regio- and stereoselectivity, not forgetting the need for greener chemistry. During the last 30 years, biocatalysis with the use of enzymes as chiral catalysts has become more common in chemistry laboratories and industrial processes. In this thesis, the use of lipases as versatile biocatalysts in the acylation of alcohols is examined both in the light of literature examples and four original publications. In the first part of the work presented in this thesis lipases were utilized in two examples concerning secondary alcohols. First, the kinetic resolution of heterocyclic aromatic secondary alcohols through transesterification was thoroughly examined including the studies of competing hydrolysis and esterification reactions. In another example, lipases were utilized in the formation of a dynamic systemic resolution (DSR) process which in turn was used as a developmental tool in the optimization of the dynamic kinetic resolution (DKR) of five heterocyclic aromatic cyanohydrins in one pot for the preparation of cyanohydrin esters as single enantiomers. In the second part of the work, the regio- and stereoselectivity of lipases was used to form sugar conjugates of glyceric and β-amino acids. The primary hydroxyl groups of methyl α-D-galacto-, -gluco- and -mannopyranosides were now acylated trough lipasecatalyzed transesterification and enantioselective lipase-catalyzed ring-opening of β- lactams, respectively.
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The artisanal production of cachaça, a beverage obtained by the fermentation of sugar cane juice after distillation, especially by small-sized producers, has traditionally used natural ferment ("fermento caipira") which consists of sugar cane juice with crushed corn, powdered rice, or citrus fruits. In despite of the difficulties in quality control due to the high level of contaminants and longer periods of preparation, the sensorial quality of the beverage may be attributed to the physiological activities of wild yeasts and even bacteria present during fermentation when this ferment is used. In this context, the aim here was to evaluate the microbiological (yeasts) and physicochemical characteristics of sugar cane juice extracted from different parts of three different varieties (RB72454, RB835486, and RB867515) of the cane stalk (lower, medium, and upper sections) in three harvesting periods (from May to December 2007) in an area under organic management. The juice from the upper section (from the eleventh internode to the top) of the sugar cane stalk could be indicated for the preparation of the natural ferment since it is as a source of yeasts and reducing sugars, especially the variety RB867515. Due to the seasonality, the best period for using this part of the sugar cane stalk is at the beginning of harvesting when the phenolic compounds are at low concentration, but there are higher number of Saccharomyces population and other yeast species. The high acidity in this section of the plant could result in a better control of bacterial contamination. These findings explain the traditional instructions of adding the upper sections for the preparation of natural ferment and can help its management in order to get a better performance with respect to organic cachaça production.
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Changes in glycolytic metabolites, nucleotide degradation products, free amino acids and other amino compounds were monitored in beef muscle (M. longissimus lumborum), stored for 21 days at 4 degrees C, in order to evaluate how post-mortem conditioning may affect flavour formation in beef. The major effects observed in sugar-related substances were the dephosphorylation of the phosphates of glucose, fructose and mannose, to yield their free sugars, as well as the breakdown of inosine 5'-monophosphate, to give a sixfold increase in ribose. Total reducing sugars increased by only 15% during conditioning, while glycogen levels remained unchanged from 2 days post-slaughter. Free amino acids increased during conditioning, particularly between days 7 and 14. Phenylalanine, methionine, lysine, leucine and isoleucine were the amino acids showing the greatest increase with conditioning time, with methionine, in particular, showing a sevenfold increase during the conditioning period. The effects of these precursor changes on cooked beef flavour are discussed. (c) 2007 Elsevier Ltd. All rights reserved.
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We have investigated the contribution of muscle components to the development of cooked meat odour in an aqueous model system using trained taste panels. Reaction mixtures were prepared with oleic, linoleic and linolenic acids with or without cysteine and ribose in a buffer with or without ferrous sulphate. Odour profiles were assessed and triangular tests were used to determine the ability of panellists to discriminate between mixtures. The presence of sugar and amino acid was highly detectable by panellists independently of the fatty acid considered (P < 0.001). However, the presence of C18:3 made differences. more obvious between mixtures than the presence of C18:1 or C18:2. `Meaty' notes were only associated with cysteine and ribose. `Fishy' notes were only apparent in C18:3 mixtures with or without sugar and amino acid, although the presence of cysteine and ribose decreased the perception. The addition of Fe+ +, a pro-oxidant present in the muscle, produced a reduction in the score of the attributes although the pattern was the same as when Fe was not used in the mixtures. Only `fishy' notes that were exclusively perceived in C18:3 mixtures showed a higher score in the presence of iron. Iron also produced a better discrimination in C18:3 mixtures, which were closely related to `grassy' notes in the presence of cysteine and ribose. (C) 2002 Published by Elsevier Science Ltd.
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PURPOSE: Consumption of sugar-reformulated products (commercially available foods and beverages that have been reduced in sugar content through reformulation) is a potential strategy for lowering sugar intake at a population level. The impact of sugar-reformulated products on body weight, energy balance (EB) dynamics and cardiovascular disease risk indicators has yet to be established. The REFORMulated foods (REFORM) study examined the impact of an 8-week sugar-reformulated product exchange on body weight, EB dynamics, blood pressure, arterial stiffness, glycemia and lipemia. METHODS: A randomized, controlled, double-blind, crossover dietary intervention study was performed with fifty healthy normal to overweight men and women (age 32.0 ± 9.8 year, BMI 23.5 ± 3.0 kg/m2) who were randomly assigned to consume either regular sugar or sugar-reduced foods and beverages for 8 weeks, separated by 4-week washout period. Body weight, energy intake (EI), energy expenditure and vascular markers were assessed at baseline and after both interventions. RESULTS: We found that carbohydrate (P < 0.001), total sugars (P < 0.001) and non-milk extrinsic sugars (P < 0.001) (% EI) were lower, whereas fat (P = 0.001) and protein (P = 0.038) intakes (% EI) were higher on the sugar-reduced than the regular diet. No effects on body weight, blood pressure, arterial stiffness, fasting glycemia or lipemia were observed. CONCLUSIONS: Consumption of sugar-reduced products, as part of a blinded dietary exchange for an 8-week period, resulted in a significant reduction in sugar intake. Body weight did not change significantly, which we propose was due to energy compensation.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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A laboratory experiment was carried out aiming to study the effects of an alkyl polyglycoside adjuvant (APG) on deposition and leaching of the herbicide tebuthiuron applied on sugar cane straw. Tebuthiuron, at concentration of 1200 mg L-1, was applied separately and in tank mix with the APG adjuvant, at concentrations of 0.07 and 0.09% (wt v-1), using a spraying volume of 204 L ha-1. A precipitation equivalent to 20 mm of rain was simulated, 24 h after the applications, to evaluate the herbicide leaching. The quantification of tebuthiuron was carried out by the high performance liquid chromatography (HPLC). It was observed that the addition of APG adjuvant at 0.07% (wt v-1) provided an increase of 11.5% in the deposition of tebuthiuron on straw, reduction of 50.4% in the drift of the herbicide and it did not affect significantly the leached amount (68.5%), when compared with the treatment where tebuthiuron was applied alone (70.8%). At the concentration of 0.09% (wt v-1), the APG adjuvant caused an increase of 22.7% in the deposition; it reduced the drift of the herbicide by 99.9% and reduced the leached amount by 7.6% thereby increasing the retention of the herbicide by straw.
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The sugar cane crop is one of the main products in Brazil and according to several authors can generate, besides the industrialized stalks, an amount of crop residues from the order of 15 to 30 % in weight of the aerial part of the plants, depending on the field conditions. The sugar cane area in Brazil is around 5.5×106 hectares, with an amount of 400.106 tons of stalks, with stalks yield of 72 tons.ha-1. This study took place in a sugar cane plot (Latitude 22°46'S, Longitude 47°23'W and 600m of altitude) with 3% of slope, located in São Paulo State. The sugar cane variety was SP 80-1816, in its forth cut, 11 months old and with a planted row spacing of 1.40 m. By other side, several sugar mills are bringing the crop residue to their patio to produce energy with the bagasse. One choice is to bring the crop residue at the same moment with the stalks, avoiding the next operation of baling it. The objective of this study was to analyze some operational parameters of two different sugar cane harvesters under the same field conditions, which was divided in four treatments: T1 = CAMECO CHT2500B operating normally; T2 = CAMECO CHT2500B operating without the cleaning system; T3 = CASE 7700 operating normally; T4 = CASE 7700 operating without the cleaning system. The results obtained were: Table presented CEB = Gross effective capacity; CEL = Net effective capacity. The conclusion is that under normal operation the CASE harvester worked better then CAMECO in the parameters CEL stalks and Manipulation efficiency. And without the cleaning system operating CASE also worked better in the parameters of CEB raw material, CEB stalks, CEL raw material and CEL stalks.
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The sugar cane crop according to several authors can generate, besides the industrialized stalks, an amount of crop residues from the order of 15 to 30% in weight of the aerial part of the plants, depending on the field conditions. The sugar cane area in Brazil is around 5.5×106 hectares, with an amount of 400.106 tons of stalks, with stalks yield of 72 tons.ha-1 (Unica, 2005). This study took place in a sugar cane plot (Latitude 22°46'S, Longitude 47°23'W and 600m of altitude) with 3% of slope, located in São Paulo State. The sugar cane variety was SP 80-1816, in its forth cut, 11 months old and with a planted row spacing of 1.40m. By other side, several sugar mills are bringing the crop residue to their patio to produce energy with the bagasse. One way for that is the baling operation to bring the crop residue at the sugar mill. Some fundamental variables were obtained to define the best set of machines to work with in sugar cane crop residue removal in the baling system among the studied ones, some of the variables were: Soil Index (T1 = 0.83%, T2 = 0.46%, T3 = 0.65%, T4 = 0.57%); Energy Efficiency (T1 = 82.48%, T2 = 83.88%, T3 = 82.83% and T4 = 82.97%) of the system and Effective Cost for Equivalent Energy in US$.EBP-1 (T1 = 11.10, T2= 10.46, T3 = 11.47 and T4 = 10.57) of the baled trash delivered at the sugar mill.
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The development of new techniques that allow the analysis and optimization of energy systems bearing in mind environmental issues is indispensable in a world with finite natural resources and growing demand of energy. Among the energy systems that deserve special attention, cogeneration in the sugar industry must be pointed out, because it uses efficiently a common fuel for generation of useful heat and power. Within this frame, thermoeconomical optimization - 2nd Law of Thermodynamics analysis by exergy function and economic evaluation of the thermal system - gradually is taking importance as a powerful tool to assist to the decision making process. Also, the explicit consideration of environmental issues offers a better way to explore trade-offs between different aspects to support the decisions that must be made. In this work it is used the technique of Life Cycle Analysis (LCA) which allows to consider environmental matters as an integral part of the problem, in opposite to most of the environmental approaches that only reduce residuals generation , without taking into account impacts associated to other related processes. On the other hand, the consideration of environmental issues in optimization of energy systems is a novel and promissory contribution in the state of the art of energy optimization and LCA. The system under study is a sugar plant of Tucumán (Argentina) given the particular importance that this industry had inside the regional economy of the Argentinean Northwest. Although cogeneration comes being used a while ago in sugar industry, being the main objective the generation of heat and as secondary objective the electric power generation and mechanic power to cover several needs of working machineries, to the date it is no available a versatile tool that allows to analyze economical feasible alternatives bearing in mind environmental issues. At sugar plants, steam is generated in boilers using as fuel bagasse - cellulosic fiber waste obtained crushing the sugar cane- and it is used to give useful heat and shaft work to the plant, but it can also be used to generate electricity with export opportunities to the electrical network. The great number of process alternatives outlines a serious decision making problem in order to take advantage of the resources. Although the problem turns out to be a mixed non-linear problem (MINLP), the main contribution of this work is the development of a hybrid strategy to evaluate cogeneration alternatives that combines optimization approaches with environmental indicators. This powerful tool for its versatility and robustness to analyze cogeneration systems, will be of great help in the decision making process, because of their easy implementation to analyze the kind of problems presented in the sugar industry.
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Background: Since sugarcane areas have increased rapidly in Brazil, the contribution of the sugarcane production, and, especially, of the sugarcane harvest system to the greenhouse gas emissions of the country is an issue of national concern. Here we analyze some data characterizing various activities of two sugarcane mills during the harvest period of 2006-2007 and quantify the carbon footprint of sugar production.Results: According to our calculations, 241 kg of carbon dioxide equivalent were released to the atmosphere per a ton of sugar produced (2406 kg of carbon dioxide equivalent per a hectare of the cropped area, and 26.5 kg of carbon dioxide equivalent per a ton of sugarcane processed). The major part of the total emission (44%) resulted from residues burning; about 20% resulted from the use of synthetic fertilizers, and about 18% from fossil fuel combustion.Conclusions: The results of this study suggest that the most important reduction in greenhouse gas emissions from sugarcane areas could be achieved by switching to a green harvest system, that is, to harvesting without burning. © 2010 de Figueiredo et al; licensee BioMed Central Ltd.
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Brazil has an important role in the biomass burning, with the detection of approximately 100,000 burning spots in a single year (2007). Most of these spots occur in the southern part of the Amazon basin during the dry season (from August to november) and these emissions reach the southeast of the country, a highly populated region and with serious urban air pollution problems. With the growing demand on biofuels, sugarcane is considerably expanding in the state of São Paulo, being a strong contributor to the bad air quality in this region. In the state of São Paulo, the main land use are pasture and sugarcane crop, that covers around 50% and 10% of the total area, respectively. Despite the aerosol from sugarcane burning having reduced atmospheric residence time, from a few days to some weeks, they might get together with those aerosol which spread over long distances (hundreds to thousands of kilometers). In the period of June through February 2010 a LIDAR observation campaign was carried in the state of São Paulo, Brazil, in order to observe and characterize optically the aerosols from two distinct sources, namely, sugar cane biomass burning and industrial emissions. For this purpose 2 LIDAR systems were available, one mobile and the other placed in a laboratory, both working in the visible (532 nm) and additionally the mobile system had a Raman channel available (607 nm). Also this campaign counted with a SODAR, a meteorological RADAR specially set up to detect aerosol echoes and gas-particle analyzers. To guarantee a good regional coverage 4 distinct sites were available to deploy the instruments, 2 in the near field of biomass burning activities (Rio Claro and Bauru), one for industrial emissions (Cubatão) and others from urban sources (São Paulo). The whole campaign provide the equivalent of 30 days of measurements which allowed us to get aerosol optical properties such as backscattering/extinction coefficients, scatter and LIDAR ratios, those were used to correlate with air quality and meteorological indicators and quantities. In this paper we should focus on the preliminary results of the Raman LIDAR system and its derived aerosol optical quantities. © 2010 Copyright SPIE - The International Society for Optical Engineering.