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Bergmann J.C.,Catholic University of Brasilia | Tupinamba D.D.,Catholic University of Brasilia | Costa O.Y.A.,Catholic University of Brasilia | Almeida J.R.M.,Embrapa Agroenergy | And 2 more authors.
Renewable and Sustainable Energy Reviews | Year: 2013

Renewable biofuels are increasingly important in the Brazilian energy matrix. In 2010, the country became the second world producer of biodiesel with a production of 2.4 million of m3 in that year, only behind Germany. In 2011, both the United States and Argentina increased production and now Brazil is the fourth world producer of biodiesel. The Brazilian biodiesel production federal program has been designed so that small family farmers, as well as large agribusiness operations, are encouraged to produce vegetable oil crops for biodiesel production. Brazil is the second largest world producer of soybeans, currently the main feedstock used for biodiesel production in the country. Due to the increasing demand for biodiesel and low oil productivity from soybean, Brazil is searching for alternative oilseed crops from which biodiesel can be produced. In this review, the current scenario for biodiesel production in Brazil is discussed, as well as vegetable oil crops that are being considered as potential biodiesel feedstocks in addition to soybeans. Brazil's biodiesel industry is currently operating only at 47% of its capacity. Therefore, it is expected that biodiesel production in Brazil will further increase. Due to the size of the country's bioethanol and biodiesel industries, Brazil can already be considered one of the world powers in sustainable biofuel production, an strategic area of the world's emerging bio-based economy. © 2013 Elsevier Ltd. All rights reserved. Source


Mazotto A.M.,Federal University of Rio de Janeiro | Couri S.,Federal University of Rio de Janeiro | Damaso M.C.T.,Embrapa Agroenergy | Vermelho A.B.,Federal University of Rio de Janeiro
International Biodeterioration and Biodegradation | Year: 2013

The isolation of native and/or the production of genetically modified enzyme-producing microorganisms may have substantial impacts on industrial processes. In this work twenty-eight Aspergillus niger mutants were screened for peptidases and keratinases production on a basal medium containing chicken feathers (1%). Four strains were selected after preliminary assays: 3T5B8, 9D40, 9D80, and 11D40. The keratinase production was higher when the A.niger strains were cultivated in a solid-state condition rather than a submerged condition: the keratinolytic activity of 3T5B8 strain was 7 times greater when cultivated by solid-state fermentation (SSF). A. niger 3T5B8 had the highest keratinase activity (172.7 U/ml) after seven days at pH 5.0 from solid-state fermentation, whereas the lowest activity was given by A.niger 9D40 after four days (21.3U/ml) from submerged fermentation. Zymography of culture supernatant showed multiple bands migrating at 40-130, 14-130, displaying activity towards keratin and gelatin substrates, respectively. This is the first study to report production of high molecular mass peptidases using a feather-degrading Aspergillus. Peptidases from strains 3T5B8, 9D40, 9D80, and 11D40 were inhibited by PMSF, except the approximately 40-kDa peptidase, which was inhibited by phenanthroline, indicating the presence of serine and metallopeptidases. The results therefore suggest that the isolates are promising keratinase producers for biotechnological purposes. © 2013 The Authors. Source


Alves A.A.,Embrapa Agroenergy | Alves A.A.,Federal University of Vicosa | Guimaraes L.M.S.,Federal University of Vicosa | Chaves A.R.M.,Federal University of Vicosa | And 2 more authors.
Acta Physiologiae Plantarum | Year: 2011

One of the most important diseases of eucalyptus plantations is caused by the rust fungus Puccinia psidii. While the genetic basis of rust resistance has been addressed recently, little is known about the physiological aspects of Eucalyptus-P. psidii interaction. In order to fill this gap, we undertook a study investigating the effects of P. psidii infection on photosynthetic processes of two E. urophylla clones with contrasting resistance to the pathogen. Our results show that gas exchange and chlorophyll a fluorescence parameters were virtually unaffected in the resistant clone. In the susceptible clone, photosynthetic rates were chiefly constrained by biochemical limitations to carbon fixation. Photosynthesis was impaired only in symptomatic tissues since the reductions in photosynthetic rates were proportional to the diseased leaf area. Rust infection provoked chronic photoinhibition to photosynthesis in the susceptible clone. Overall, differences in the ability for light capture, use and dissipation may play a significant role in explaining the clonal differences in Eucalyptus in response to P. psidii infection. To our knowledge, this is the first report of the effect of rust infection on gas exchange and chlorophyll a fluorescence parameters in Eucalyptus. © 2011 Franciszek Górski Institute of Plant Physiology, Polish Academy of Sciences, Kraków. Source


Murad A.M.,Catholic University of Brasilia | Molinari H.B.C.,Embrapa Agroenergy | Magalhaes B.S.,Catholic University of Brasilia | Franco A.C.,University of Brasilia | And 4 more authors.
PLoS ONE | Year: 2014

Sugarcane (Saccharum spp.) is the world most productive sugar producing crop, making an understanding of its stress physiology key to increasing both sugar and ethanol production. To understand the behavior and salt tolerance mechanisms of sugarcane, two cultivars commonly used in Brazilian agriculture, RB867515 and RB855536, were submitted to salt stress for 48 days. Physiological parameters including net photosynthesis, water potential, dry root and shoot mass and malondialdehyde (MDA) content of leaves were determined. Control plants of the two cultivars showed similar values for most traits apart from higher root dry mass in RB867515. Both cultivars behaved similarly during salt stress, except for MDA levels for which there was a delay in the response for cultivar RB867515. Analysis of leaf macro- and micronutrients concentrations was performed and the concentration of Mn2+ increased on day 48 for both cultivars. In parallel, to observe the effects of salt stress on protein levels in leaves of the RB867515 cultivar, two-dimensional gel electrophoresis followed by MS analysis was performed. Four proteins were differentially expressed between control and salt-treated plants. Fructose 1,6-bisphosphate aldolase was down-regulated, a germin-like protein and glyceraldehyde 3-phosphate dehydrogenase showed increased expression levels under salt stress, and heat-shock protein 70 was expressed only in salt-treated plants. These proteins are involved in energy metabolism and defense-related responses and we suggest that they may be involved in protection mechanisms against salt stress in sugarcane. © 2014 Murad et al. Source


Laviola B.G.,Embrapa Agroenergy | Oliveira A.M.C.E.,Federal University of Vicosa | Bhering L.L.,Federal University of Vicosa | Alves A.A.,Embrapa Agroenergy | And 3 more authors.
Industrial Crops and Products | Year: 2013

The aim of this study was to estimate the repeatability coefficient of grain production in Jatropha, the minimum number of measurements needed to reliably predict the genetic value of selected families, and to determine the cumulative genetic gains when considering the selection of the best families based on different number of measurements. The experiment was conducted with 175 accessions (half-siblings progenies derived from selected plants in the field) that compose part of a germplasm collection. Such bank was established in a randomized block design with two blocks. In each block a given accession was represented in a 5plant/plot scheme (half-siblings). For the analysis, yield data obtained in the years of 2009-2012 were considered. The results of this study indicate that the repeatability coefficient of grain production in Jatropha is low (0.37), but comparable to other perennial species, and that to achieve reliabilities of 70 and 80% in the prediction of breeding values of selected families, 4 and 7 years of evaluation, respectively, are needed. The results of this study also indicate that the efficiency of early selection seems to be small in Jatropha since the coincidence rate of selected genotypes at early age (1 or 2 years of evaluation) and genotypes selected in adult age (4 years assessment) is small (17-23%). Finally, taking into account the repeatability coefficients and coefficients of determination, in a hypothetical period of 21 years (which is equivalent to three selection cycles using seven consecutive measurements - R2=80%), this paper demonstrates that higher cumulative genetic gains can be obtained (159% over 108%) by relaxing the degree of certainty in predicting the best families (R2=65% instead of R2=80%), since it makes possible to perform a greater number of selection cycles in the same period (7 cycles instead of 4). © 2013 Elsevier B.V. Source

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