Effects of abscisic acid, ethylene and sugars on the mobilization of storage proteins and carbohydrates in seeds of the tropical tree Sesbania virgata (Leguminosae)

Endospermic legumes are abundant in tropical forests and their establishment is closely related to the mobilization of cell-wall storage polysaccharides. Endosperm cells also store large numbers of protein bodies that play an important role as a nitrogen reserve in this seed. In this work, a systems approach was adopted to evaluate some of the changes in carbohydrates and hormones during the development of seedlings of the rain forest tree Sesbania virgata during the period of establishment. Seeds imbibed abscisic acid (ABA), glucose and sucrose in an atmosphere of ethylene, and the effects of these compounds on the protein contents, alpha-galactosidase activity and endogenous production of ABA and ethylene by the seeds were observed. The presence of exogenous ABA retarded the degradation of storage protein in the endosperm and decreased alpha-galactosidase activity in the same tissue during galactomannan degradation, suggesting that ABA represses enzyme action. On the other hand, exogenous ethylene increased alpha-galactosidase activity in both the endosperm and testa during galactomannan degradation, suggesting an inducing effect of this hormone on the hydrolytic enzymes. Furthermore, the detection of endogenous ABA and ethylene production during the period of storage mobilization and the changes observed in the production of these endogenous hormones in the presence of glucose and sucrose, suggested a correlation between the signalling pathway of these hormones and the sugars. These findings suggest that ABA, ethylene and sugars play a role in the control of the hydrolytic enzyme activities in seeds of S. virgata, controlling the process of storage degradation. This is thought to ensure a balanced flow of the carbon and nitrogen for seedling development.

Boron influence on concentration of polyols and other sugars in Eucalyptus

Embora a função do elemento Boro (B) nas plantas ainda não tenha sido bem esclarecida, várias hipóteses vêm sido levantadas. Uma das funções atribuídas a esse elemento é a síntese de carboidratos. Com o objetivo de avaliar o efeito do B sobre a síntese de alguns polióis e açúcares em Eucalyptus grandis e híbridos urograndis, estes foram submetidos à situação de suprimento e restrição de B. O experimento foi conduzido em casa de vegetação de acordo com o delineamento de blocos casualizados com cinco repetições, e os elementos nutricionais, assim como o B, foram fornecidos na forma de solução nutritiva. Não se observou diferença significativa nos teores de manitol, sorbitol, myo-inositol e scyllo-inositol e dos açúcares α-glicose e β-glicose entre E. grandis e híbridos. Arabinose foi o único a apresentar maior teor em E. grandis em restrição de B. O efeito da presença do B foi bastante expressivo, mas em suprimento do elemento as plantas apresentaram acréscimo significativo na síntese dos compostos avaliados.

Seleção de microrganismos celulolíticos, imobilização e aplicação das celulases, produzidas e comercial, na hidrólise da celulose

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Soluble sugars and germination of Annona emarginata (Schltdl.) H. Rainer seeds submitted to immersion in GA3 up to different water contents

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Produção de etanol utilizando mix de sorgo sacarino e cana-de-açúcar em processo de maturação

Pós-graduação em Microbiologia Agropecuária - FCAV

Sugars Electrooxidation at Glassy Carbon Electrode Decorate with Multi-Walled Carbon Nanotubes with Nickel Oxy-Hydroxide

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

An Electrochemical Sensor for Reducing Sugars Based on a Glassy Carbon Electrode Modified with Electropolymerized Molecularly Imprinted Poly-o-phenylenediamine Film

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

Total sugars in atmospheric aerosols: an alternative tracer for biomass burning

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

Effect of ethanol, dry extract and reducing sugars on density and viscosity of Brazilian red wines

BACKGROUND Density and viscosity are properties that exert great influence on the body of wines. The present work aimed to evaluate the influence of the alcoholic content, dry extract, and reducing sugar content on density and viscosity of commercial dry red wines at different temperatures. The rheological assays were carried out on a controlled stress rheometer, using concentric cylinder geometry at seven temperatures (2, 8, 14, 16, 18, 20 and 26 degrees C).RESULTSWine viscosity decreased with increasing temperature and density was directly related to the wine alcohol content, whereas viscosity was closely linked to the dry extract. Reducing sugars did not influence viscosity or density. Wines produced from Italian grapes were presented as full-bodied with higher values for density and viscosity, which was linked to the higher alcohol content and dry extract, respectively.CONCLUSIONThe results highlighted the major effects of certain physicochemical properties on the physical properties of wines, which in turn is important for guiding sensory assessments. (c) 2014 Society of Chemical Industry

Sugars metabolism and ethanol production by different yeast strains from coffee industry wastes hydrolysates

Significant amounts of wastes are generated by the coffee industry, among of which, coffee silverskin (CS) and spent coffee grounds (SCG) are the most abundantly generated during the beans roasting and instant coffee preparation, respectively. This study evaluated the sugars metabolism and production of ethanol by three different yeast strains (Saccharomyces cerevisiae, Pichia stipitis and Kluyveromyces fragilis) when cultivated in sugar rich hydrolysates produced by acid hydrolysis of CS and SCG. S. cerevisiae provided the best ethanol production from SCG hydrolysate (11.7 g/l, 50.2% efficiency). On the other hand, insignificant (<= 1.0 g/l) ethanol production was obtained from CS hydrolysate, for all the evaluated yeast strains, probably due to the low sugars concentration present in this medium (approx. 22 g/l). It was concluded that it is possible to reuse SCG as raw material for ethanol production, which is of great interest for the production of this biofuel, as well as to add value to this agro-industrial waste. CS hydrolysate, in the way that is produced, was not a suitable fermentation medium for ethanol production; however, the hydrolysate concentration for the sugars content increase previous the use as fermentation medium could be an alternative to overcome this problem. (C) 2011 Elsevier Ltd. All rights reserved.

On the formation of carbonate adducts of fatty alcohols, sterols, and sugars in biological conditions

The formation and properties of carbonate adducts of some organic hydroxy compounds in aqueous medium were investigated. Fatty alcohols and sugars were chosen as representative classes of biological interest, and the medium was carbonated aqueous solution with pH ranging from 3.0 to 8.3. Capillary electrophoresis with two capacitively coupled contactless conductivity detectors (C4Ds) was used for quantitation and to obtain the mobility of the monoalkyl carbonates (MACs), which were used to determine the equilibrium and kinetic constants of the reaction as well as the diffusion coefficients. For increasing chain length of the alcohols, the equilibrium constant tends to the unit, which suggests that fatty alcohols can form the corresponding MACs. The formation of MACs for cyclohexanol and cyclopentanol also suggest the existence of similar species for sterols. Carbonate adducts of fructose, glucose, and sucrose were also detected, which suggests that these counterparts of the well-known phosphates can also occur in the cytosol. Our calculations suggest that one in 1000 to one in 10 000 molecules of these hydroxy compounds would be available as the corresponding MAC in such a medium. Experiments carried out at pH values less than 3.0 showed that there is a catalytic effect of hydronium on the interconversion of bicarbonate and a MAC. Taking into account the great number of hydroxy compounds similar to the ones investigated and that bicarbonate is ubiquitous in living cells, one can anticipate the existence of a whole new class of carbonate adducts of these metabolites.

Adding value to the Brazilian sisal: acid hydrolysis of its pulp seeking production of sugars and materials

The present work is inserted into the broad context of the upgrading of lignocellulosic fibers. Sisal was chosen in the present study because more than 50% of the world's sisal is cultivated in Brazil, it has a short life cycle and its fiber has a high cellulose content. Specifically, in the present study, the subject addressed was the hydrolysis of the sisal pulp, using sulfuric acid as the catalyst. To assess the influence of parameters such as the concentration of the sulfuric acid and the temperature during this process, the pulp was hydrolyzed with various concentrations of sulfuric acid (30-50%) at 70 A degrees C and with 30% acid (v/v) at various temperatures (60-100 A degrees C). During hydrolysis, aliquots were withdrawn from the reaction media, and the solid (non-hydrolyzed pulp) was separated from the liquid (liquor) by filtering each aliquot. The sugar composition of the liquor was analyzed by HPLC, and the non-hydrolyzed pulps were characterized by viscometry (average molar mass), and X-ray diffraction (crystallinity). The results support the following conclusions: acid hydrolysis using 30% H2SO4 at 100 A degrees C can produce sisal microcrystalline cellulose and the conditions that led to the largest glucose yield and lowest decomposition rate were 50% H2SO4 at 70 A degrees C. In summary, the study of sisal pulp hydrolysis using concentrated acid showed that certain conditions are suitable for high recovery of xylose and good yield of glucose. Moreover, the unreacted cellulose can be targeted for different applications in bio-based materials. A kinetic study based on the glucose yield was performed for all reaction conditions using the kinetic model proposed by Saeman. The results showed that the model adjusted to all 30-35% H2SO4 reactions but not to greater concentrations of sulfuric acid. The present study is part of an ongoing research program, and the results reported here will be used as a comparison against the results obtained when using treated sisal pulp as the starting material.

Added sugars: consumption and associated factors among adults and the elderly. São Paulo, Brazil

OBJECTIVE: To investigate added sugar intake, main dietary sources and factors associated with excessive intake of added sugar. METHODS: A population-based household survey was carried out in São Paulo, the largest city in Brazil. Cluster sampling was performed and the study sample comprised 689 adults and 622 elderly individuals. Dietary intake was estimated based on a 24-hour food recall. Usual nutrient intake was estimated by correcting for the within-person variance of intake using the Iowa State University (ISU) method. Linear regression analysis was conducted to identify factors associated with added sugar intake. RESULTS: Average of energy intake (EI) from added sugars was 9.1% (95% CI: 8.9%; 9.4%) among adults and 8.4% (95% CI: 8.2%; 8.7%) among the elderly (p < 0.05). Average added sugar intake (% EI) was higher among women than among men (p < 0.05). Soft drink was the main source of added sugar among adults, while table sugar was the main source of added sugar among the elderly. Added sugar intake increased with age among adults. Moreover, higher socioeconomic level was associated with added sugar intake in the same group. CONCLUSIONS: Added sugar intake is higher among younger adults of higher socioeconomic level. Soft drink and table sugar accounted for more than 50% of the sugar consumed.

Jasmonate-dependent depletion of soluble sugars compromises plant resistance to Manduca sexta

Jasmonates regulate plant secondary metabolism and herbivore resistance. How they influence primary metabolites and how this may affect herbivore growth and performance are not well understood. We profiled sugars and starch of jasmonate biosynthesis-deficient and jasmonate-insensitive Nicotiana attenuata plants and manipulated leaf carbohydrates through genetic engineering and in vitro complementation to assess how jasmonate-dependent sugar accumulation affects the growth of Manduca sexta caterpillars. We found that jasmonates reduce the constitutive and herbivore-induced concentration of glucose and fructose in the leaves across different developmental stages. Diurnal, jasmonate-dependent inhibition of invertase activity was identified as a likely mechanism for this phenomenon. Contrary to our expectation, both in planta and in vitro approaches showed that the lower sugar concentrations led to increased M. sexta growth. As a consequence, jasmonate-dependent depletion of sugars rendered N. attenuata plants more susceptible to M. sexta attack. In conclusion, jasmonates are important regulators of leaf carbohydrate accumulation and this determines herbivore growth. Jasmonate-dependent resistance is reduced rather than enhanced through the suppression of glucose and fructose concentrations, which may contribute to the evolution of divergent resistance strategies of plants in nature.