The accumulation process and agrofood networks in Latin America

Includes bibliography

Acúmulo de biomassa em variedades de cana-de-açúcar inoculadas com diferentes estirpes de bactérias diazotróficas

The objective of this study was to evaluate the contribution of inoculation with diazotrophs, applied both individually and in combination, in commercial varieties of sugarcane. The experiment was carried out at the experimental grounds of Embrapa Agrobiologia, in Seropédica, Rio de Janeiro, Brazil. The experimental design was of randomised blocks, with sub-divided plots and six replications. Six varieties of sugarcane with six treatments were used: control, control with nitrogen, inoculation of the individual strains: BR 11512, BR 11724 and BR 11411, in addition to inoculation with a cocktail consisting of five strains of diazotrophs. Differences were observed between varieties and between treatments, and an interaction observed between the treatments and varieties. For all the parameters evaluated, no response was observed in the sugarcane varieties RB855536 and RB92606. In the variety RB918639, the only difference was in the accumulation of green biomass. No difference was observed between the treatments for total nitrogen accumulation. The most responsive variety to inoculation was RB867515, differing in the accumulation of fresh and dry biomass. This study showed that inoculation promotes the accumulation of biomass, the contribution being different for the varieties and strains of bacteria, suggesting an interaction between the factors studied. The variety RB867515 is promising for use in studies of inoculation with diazotrophs.

Social use of the surplus, accumulation, distribution and employment

Includes bibliography

The process of accumulation and the weakness of the protagonists

Includes bibliography

Use of different carbon sources in cultivation of baker's yeast for production of glycerol-3-phosphate dehydrogenase

The physiological state of yeast cells changes during culture growth as a consequence of environmental changes (nutrient limitations, pH and metabolic products). Cultures that grow exponentially are heterogeneous cell populations made up of cells regulated by different metabolic and/or genetic control systems. The strain of baker's yeast selected by plating commercial compressed yeast was used for the production of glycerol-3- phosphate dehydrogenase. Glycerol-3-phosphate dehydrogenase (GPD) has been widely used in the enzyme assays with diverse compounds of industrial interest, such as glycerol or glycerol phosphate, as well as a number of important bioanalytical applications. Each cell state determines the level of key enzymes (genetic control), fluxes through metabolic pathways (metabolic control), cell morphology and size. The present study was carried out to determine the effects of environmental conditions and carbon source on GPD production from baker's yeast. Glucose, glycerol, galactose and ethanol were used as carbon sources. Glycerol and ethanol assimilations required agitation, which was dependent on the medium volume in the fermentation flask for the greatest accumulation of intracellular GPD. Enzyme synthesis was also affected by the initial pH of the medium and inoculum size. The fermentation time required for a high level of enzyme formation decreased with the inoculum size. The greatest amount of enzyme (0.45 U/ml) was obtained with an initial pH of 4.5 in the medium containing ethanol or glycerol. The final pH was maintained in YP-ethanol, but in the YP-glycerol the final pH increased to 6.9 during growth.

Moderate physical activity from childhood contributes to metabolic health and reduces hepatic fat accumulation in adult rats

Background: Obesity, oxidative stress and inflammation, by triggering insulin resistance, may contribute to the accumulation of hepatic fat, and this accumulation by lipotoxicity can lead the organ to fail. Because obesity is growing at an alarming rate and, worryingly, in a precocious way, the present study aimed to investigate the effects of moderate physical training performed from childhood to adulthood on liver fat metabolism in rats. Methods. Twenty rats that were 28days old were divided into two groups: control (C) and trained (T). The C Group was kept in cages without exercise, and the T group was submitted to swimming exercise for 1hour/day, 5days/week from 28 to 90days of age (8weeks) at 80% of the anaerobic threshold determined by the lactate minimum test. At the end of the experiment, the body weight gain, insulin sensitivity (glucose disappearance rate during the insulin tolerance test), concentrations of free fatty acids (FFA) and triglycerides (TG) and hepatic lipogenic rate were analyzed. For the statistical analysis, the Student t-test was used with the level of significance preset at 5%. Results: The T group showed lower body weight gain, FFA concentrations, fat accumulation, hepatic lipogenic rate and insulin resistance. Conclusion: The regular practice of moderate physical exercise from childhood can contribute to the reduction of obesity and insulin resistance and help prevent the development of accumulation of hepatic fat in adulthood. © 2013de Moura et al; licensee BioMed Central Ltd.

Does excess weight interfere with bone mass accumulation during adolescence?

Obesity and osteoporosis are important global health problems characterized by increasing prevalence with high impact on morbidity and mortality. The objective of this review was to determine whether excess weight during adolescence interferes with bone mass accumulation. If bone mineral gain can be optimized during puberty, adults are less likely to suffer from the devastating complications of osteoporosis. The increased fracture risk in obese children has also been attributed to a lower bone mass for weight compared to non-obese children. Thus, adiposity present in this age group may not result in the protection of bone mass, in contrast to what has been observed in adults. However, studies involving adolescents have reported both protective and detrimental effects of obesity on bone. The results and mechanisms of these interactions are controversial and have not been fully elucidated, a fact highlighting the extreme relevance of this topic and the need to monitor intervening and interactive variables. © 2013 by the authors; licensee MDPI, Basel, Switzerland.

Nutrient accumulation in 'Fantasy' net melon cultivated on substrate

Knowledge of the most essential nutrients for plant growth facilitates the efficient handling of its nutrition, especially when they are grown on a substrate supported by fertigation. The objective of this study was to determine the accumulation of nutrients in net melon grown on a substrate and understand the relationship between mineral nutrition and plant growth. The Fantasy hybrid was cultivated in pots containing a substrate consisting of a mixture of sand and peanut shells (ratio, 1:1). Determination of nutrient accumulation was performed in 6 seasons. The substrate was chemically characterized before and after cultivation. Harvesting occurred 78 days after transplantation, resulting in an average yield of 70,120 kg·ha-1. Substrate analysis showed a small increase in nutrient levels by the end of cultivation. The order of nutrient accumulation was as follows: N>Ca>K>P>Mg>S>B> Fe>Mn>Zn>Cu.

Efeito residual de fontes de fósforo nos atributos químicos do solo, nutrição e produtividade de biomassa da cana-de-açúcar

In tropical regions, the residual effect of phosphate fertilizer source is of crucial importance. This study aimed to evaluate the effects of application of P sources in chemical properties of soil, nutrition and productivity of sugarcane plant and during the first and second ratoon. The sources of P applied in furrows at planting were, triple superphosphate, Arad phosphate, bone meal (100 kg ha-1 P2O5 total) and a control without P, the varieties of sugarcane studied were IAC86-2480 and SP79-1011. A randomized block design in a 4 × 2 factorial was used, with four replications. The study was conducted in the municipality of Alta Floresta-MT, Brazil, in Typic Hapludox. After each cutting, in soil P content, pH and Ca were evaluated. In the plant, the production of green and dry matter of shoots, the concentration of P in the biomass harvested, the export of P and agronomic efficiency of the sources of P were determined. The bone meal had a higher agronomic efficiency resulted in greater accumulation and export of P by crop, higher content of available Ca and P and increase soil pH. The Arad reactive phosphate increased its agronomic efficiency between crop cycles.

Biomass-to-bio-products application of feruloyl esterase from Aspergillus clavatus

The structural polysaccharides contained in plant cell walls have been pointed to as a promising renewable alternative to petroleum and natural gas. Ferulic acid is a ubiquitous component of plant polysaccharides, which is found in either monomeric or dimeric forms and is covalently linked to arabinosyl residues. Ferulic acid has several commercial applications in food and pharmaceutical industries. The study herein introduces a novel feruloyl esterase from Aspergillus clavatus (AcFAE). Along with a comprehensive functional and biophysical characterization, the low-resolution structure of this enzyme was also determined by small-angle X-ray scattering. In addition, we described the production of phenolic compounds with antioxidant capacity from wheat arabinoxylan and sugarcane bagasse using AcFAE. The ability to specifically cleave ester linkages in hemicellulose is useful in several biotechnological applications, including improved accessibility to lignocellulosic enzymes for biofuel production. © 2012 Springer-Verlag Berlin Heidelberg.

Influence of specimen size, tray inclination and air flow rate on the emission of gases from biomass combustion

Experiments of biomass combustion were performed to determine whether specimen size, tray inclination, or combustion air flow rate was the factor that most affects the emission of carbon dioxide, carbon monoxide, and methane. The chosen biomass was Eucalyptus citriodora, a very abundant species in Brazil, utilized in many industrial applications, including combustion for energy generation. Analyses by gas chromatograph and specific online instruments were used to determine the concentrations of the main emitted gases, and the following figures were found for the emission factors: 1400 ± 101 g kg-1 of CO2, 50 ± 13 g kg-1 of CO, and 3.2 ± 0.5 g kg-1 of CH4, which agree with values published in the literature for biomass from the Amazon rainforest. Statistical analysis of the experiments determined that specimen size most significantly affected the emission of gases, especially CO2 and CO. •Statistical analysis to determine effects on emission factors.•CO2, CO, CH4 emission factors determined for combustion of Eucalyptus.•Laboratory results agreed with data for Amazonian biomass combustion in field tests.•Combustion behavior under flaming and smoldering was analyzed. © 2013 Elsevier Ltd.

An analysis of diurnal cycles in the mass of ambient aerosols derived from biomass burning and agro-industry

Strong diurnal cycles in ambient aerosol mass were observed in a rural region of Southeast Brazil where the trace composition of the lower troposphere is governed mainly by emissions from agro-industry. An optical particle counter was used to record size-segregated aerosol number concentrations between 13 May 2010 and 15 March 2011. The data were collected every 10 min and used to calculate aerosol mass concentrations. Aerosol samples were also collected onto filters during daytime (10:00-16:00 local time) and nighttime (20:00-06:00) periods, for subsequent analysis of soluble ions and water-soluble organic carbon. Biomass burning aerosols predominated during the dry winter, while secondary aerosols were most important in the summer rainy season. In both seasons, diurnal cycles in calculated aerosol mass concentrations were due to the uptake of water by the aerosols and, to a lesser extent, to emissions and secondary aerosol formation. In neither season could the observed mass changes be explained by changes in the depth of the boundary layer. In the summer, nighttime increases in aerosol mass ranged from 2.7-fold to 81-fold, depending on particle size, while in the winter, the range was narrower, from 2.2-fold to 9.5-fold, supporting the possibility that the presence of particles derived from biomass burning reduced the overall ability of the aerosols to absorb water. Key Points Diurnal cycle of agro-industrial aerosol mass governed by humidity Biomass burning emissions act to suppress particle growth Need to consider diurnal mass cycles in aerosol dry deposition models ©2013. American Geophysical Union. All Rights Reserved.

Biosorption of cadmium (II) and lead (II) from aqueous solution using exopolysaccharide and biomass produced by Colletotrichum sp.

The biosorption of Cd(II) and Pb(II) ions on biomass and exopolysaccharide (EPS) produced by Colletotrichum sp. fungus has been investigated as a function of contact time, initial pH, initial metal ion concentration, and initial adsorbent concentration in a batch system. Adsorption equilibrium was described by Freundlich and Langmuir isotherms. Adsorption was characterized through granulometry, SEM and EDX analysis. Then, studies were performed to regenerate the adsorbent. Biosorption of metals by biomass and EPS were best described by the Langmuir and Freundlich isotherm, respectively. Results of thermodynamic investigations showed that adsorption reactions were spontaneous (ΔG° < 0), exothermal, and mainly physical. The EPS was able to remove 79 and 98% of cadmium and lead, respectively, and the biomass removed 85 and 84% of cadmium and lead, respectively, in a solution with initial concentration 100 mg L-1, and the four adsorption-desorption cycles of all adsorbents showed up with great regenerative capacity and relative stability after these four cycles, the high potential of these biological materials in sorption has been shown. © 2013 Copyright Balaban Desalination Publications.

Sorghum grain yield, forage biomass production and revenue as affected by intercropping time

Sorghum is an excellent alternative to other grains in poor soil where corn does not develop very well, as well as in regions with warm and dry winters. Intercropping sorghum [Sorghum bicolor (L.) Moench] with forage crops, such as palisade grass [Brachiaria brizantha (Hochst. ex A. Rich) Stapf] or guinea grass (Panicum maximum Jacq.), provides large amounts of biomass for use as straw in no-tillage systems or as pasture. However, it is important to determine the appropriate time at which these forage crops have to be sown into sorghum systems to avoid reductions in both sorghum and forage production and to maximize the revenue of the cropping system. This study, conducted for three growing seasons at Botucatu in the State of São Paulo in Brazil, evaluated how nutrient concentration, yield components, sorghum grain yield, revenue, and forage crop dry matter production were affected by the timing of forage intercropping. The experimental design was a randomized complete block design. Intercropping systems were not found to cause reductions in the nutrient concentration in sorghum plants. The number of panicles per unit area of sorghum alone (133,600), intercropped sorghum and palisade grass (133,300) and intercropped sorghum and guinea grass (134,300) corresponded to sorghum grain yields of 5439, 5436 and 5566kgha-1, respectively. However, the number of panicles per unit area of intercropped sorghum and palisade grass (144,700) and intercropped sorghum and guinea grass (145,000) with topdressing of fertilizers for the sorghum resulted in the highest sorghum grain yields (6238 and 6127kgha-1 for intercropping with palisade grass and guinea grass, respectively). Forage production (8112, 10,972 and 13,193Mg ha-1 for the first, second and third cuts, respectively) was highest when sorghum and guinea grass were intercropped. The timing of intercropping is an important factor in sorghum grain yield and forage production. Palisade grass or guinea grass must be intercropped with sorghum with topdressing fertilization to achieve the highest sorghum grain yield, but this significantly reduces the forage production. Intercropping sorghum with guinea grass sown simultaneously yielded the highest revenue per ha (€ 1074.4), which was 2.4 times greater than the revenue achieved by sowing sorghum only. © 2013 Elsevier B.V.