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Composição química e atividade biológica de resíduos agroindustriais; Chemical composition and biological activity of agroindustrial residues

Melo, Priscilla Siqueira
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 10/09/2010 PT
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A agroindústria tem se expandido para atender a crescente demanda populacional por alimentos. Dentro deste contexto, o Brasil com sua economia fortemente baseada no agronegócio contribui para a geração de grande quantidade de resíduos agroindustriais resultantes das atividades de processamento. Estes resíduos, por sua vez, representam um grave problema, pois aparentemente sem aplicação viável, são descartados diretamente ao meio ambiente. Muitos deles são ricos em compostos bioativos, amplamente reconhecidos pelas suas propriedades promotoras de saúde e aplicações tecnológicas, tais como antioxidantes e antimicrobianos, representando, portanto, potenciais fontes naturais destas substâncias. Neste trabalho, foram analisados 15 resíduos agroindustriais coletados em Bento Gonçalves, RS, Petrolina, PE, Monte Alto e Jacareí, SP. São eles: bagaços de uva Pinot Noir, Petit Verdot, Cabernet Sauvignon, Isabel (tintas), Moscato, Verdejo (brancas); engaços de uva Cabernet Sauvignon; Syrah (tintas), Moscato, Verdejo (brancas); borras de vinho tinto e branco; bagaço de tomate; bagaço de goiaba e bagaço de malte. As amostras foram extraídas com solventes de diferentes polaridades (hexano, clorofórmio, acetato de etila...

Production of xylanase and CMCase on solid state fermentation in different residues by Thermoascus aurantiacus miehe

Silva, Roberto da; Lago, Ellen S.; Merheb, Carolina W.; Macchione, Mariana M.; Park, Yong Kun; Gomes, Eleni
Fonte: Sociedade Brasileira de Microbiologia Publicador: Sociedade Brasileira de Microbiologia
Tipo: Artigo de Revista Científica Formato: 235-241
ENG
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56.11%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); O emprego de residuos como matéria prima é importante como estrategia governamental e para o balanço ambiental. O propósito deste trabalho foi estudar a produção de CMCase e xilanase de uma linhagem de Thermoascus aurantiacus isolado de solo brasileiro em fermentação em estado sólido (SSF) usando diferentes resíduos agrícolas (farelo de trigo, bagaço de cana, bagaço de laranja, sabugo de milho, grama verde, grama seca, serragem de eucalipto e palha de milho) como substratos sem enriquecimento dos meios e caracterizar as enzimas. O estudo das enzimas hemiceluloliticas extracelulares mostrou que o fungo T. arantiacus é mais xilanolítico do que celulolítico. Ele produziu maiores níveis das enzimas em meios contendo sabugo de milho, grama e palha de milho. Todas as enzimas foram estáveis por 24 h à temperatura ambiente numa ampla faixa de pH (3,0 - 9,0) e também foram estáveis a 60ºC por 1 h. O pH ótimo e temperatura ótima para xilanase e CMCase foram 5,0- 5,5 e 5,0 e 75ºC, respectivamente. O microrganismo cresceu muito bem estacionariamente no meio simples, de baixo custo. As enzimas estáveis secretadas extracelularmente apresentam as características necessárias para sua aplicação industrial.; The use of waste as raw material is important for government economy and natural balance. The purpose of this work was to study the production of CMCase and xylanase by a Brazilian strain of Thermoascus aurantiacus in solid state fermentation (SSF) using different agricultural residues (wheat bran...

Assessment of the genotoxicity of two agricultural residues after processing by diplopods using the Allium cepa assay

Christofoletti, Cintya A.; Pedro-Escher, Janaína; Fontanetti, Carmem S.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica
ENG
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46.22%
Agroindustrial by-products and residues from treatment of sewage sludge have been recently recycled as soil amendments. This study was aimed at assessing toxic potential of biosolid, obtained from a sewage treatment plant (STP), vinasse, a by-product of the sugar cane industry, and a combination of both residues using Allium cepa assay. Bioprocessing of these samples by a terrestrial invertebrate (diplopod Rhinocricus padbergi) was also examined. Bioassay assembly followed standards of the Brazilian legislation for disposal of these residues. After adding residues, 20 diplopods were placed in each terrarium, where they remained for 30 days. Chemical analysis and the A. cepa assay were conducted before and after bioprocessing by diplopods. At the end of the bioassay, there was a decrease in arsenic and mercury. For the remaining metals, accumulation and/or bioavailability varied in all samples but suggested bioprocessing by animals. The A. cepa test revealed genotoxic effects characterized by different chromosome aberrations. Micronuclei and chromosome breaks on meristematic cells and F1 cells with micronuclei were examined to assess mutagenicity of samples. After 30 days, the genotoxic effects were significantly reduced in the soil + biosolid and soil + biosolid + vinasse groups as well as the mutagenic effects in the soil + biosolid + vinasse group. Similar to vermicomposting...

Detoxification of hemicellulosic hydrolysates from extracted olive pomace by diananofiltration

Brás, Teresa; Guerra, Vera; Torrado, Ivone; Lourenço, Pedro; Carvalheiro, Florbela; Duarte, Luís C.; Neves, Luisa A.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em //2014 ENG
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46.04%
Xylitol can be obtained from the pentose-rich hemicellulosic fraction of agricultural residues, such as extracted olive pomace, by fermentation. Dilute acid hydrolysis of lignocellulosic materials, produces the release of potential inhibitory compounds mainly furan derivatives, aliphatic acids, and phenolic compounds. In order to study the potential on the increase of the hydrolysate fermentability, detoxification experiments based on diananofiltration membrane separation processes were made. Two membranes, NF270 and NF90, were firstly evaluated using hydrolysate model solutions under total recirculation mode, to identify the best membrane for the detoxification. NF270 was chosen to be used in the diananofiltration experiment as it showed the lowest rejection for toxic compounds and highest permeate flux. Diananofiltration experiments, for hydrolysate model solutions and hydrolysate liquor, showed that nanofiltration is able to deplete inhibitory compounds and to obtain solutions with higher xylose content. Conversely to non-detoxified hydrolysates, nanofiltration detoxified hydrolysates enabled yeast growth and xylitol production by the yeast Debaryomyces hansenii, clearly pointing out that detoxification is an absolute requirement for extracted olive pomace dilute acid hydrolysate bioconversion.

Characterization and treatment of sisal fiber residues for cement-based composite application

Lima,Paulo R. L.; Santos,Rogério J.; Ferreira,Saulo R.; Toledo Filho,Romildo D.
Fonte: Associação Brasileira de Engenharia Agrícola Publicador: Associação Brasileira de Engenharia Agrícola
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/2014 EN
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46.26%
Sisal fiber is an important agricultural product used in the manufacture of ropes, rugs and also as a reinforcement of polymeric or cement-based composites. However, during the fiber production process a large amount of residues is generated which currently have a low potential for commercial use. The aim of this study is to characterize the agricultural residues by the production and improvement of sisal fiber, called field bush and refugo and verify the potentiality of their use in the reinforcement of cement-based composites. The residues were treated with wet-dry cycles and evaluated using tensile testing of fibers, scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy. Compatibility with the cement-based matrix was evaluated through the fiber pull-out test and flexural test in composites reinforced with 2 % of sisal residues. The results indicate that the use of treated residue allows the production of composites with good mechanical properties that are superior to the traditional composites reinforced with natural sisal fibers.

Use of maize cob for production of particleboard

Scatolino,Mário Vanoli; Silva,Danillo Wisky; Mendes,Rafael Farinassi; Mendes,Lourival Marin
Fonte: Editora da Universidade Federal de Lavras Publicador: Editora da Universidade Federal de Lavras
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2013 EN
Relevância na Pesquisa
46.19%
Agricultural residues are materials generated in large quantities in Brazil and can accumulate to such extent as to cause environmental problems. Among agricultural residues, maize cob is one worthy of notice, and an alternative use for maize cob would be to produce particleboard panels in association with wood particles. This study aimed to evaluate the feasibility of using maize cob for production of particleboard panels. The following maize cob percentages were used: 0%, 25%, 50%, 75% and 100%, in association with particles of Pinus oocarpa wood. Panels were made with 8% of urea formaldehyde and 1% of paraffin (based on dry weight of particles). For compressing the panels, a pressure of 3.92 MPa was applied at a temperature of 160º C, for 8 minutes. Increased replacement of pinewood by maize cob residue promoted significant improvements to the properties water absorption after two hours of immersion, thickness swelling after two and after twenty-four hours of immersion. Mechanical properties had a decreasing correlation with the maize cob percentage being incorporated.

Optimization of fibrinolytic protease production from Bacillus subtilis I-2 using agro-residues

Bajaj,Bijender Kumar; Singh,Satbir; Khullar,Mowkshi; Singh,Kaurab; Bhardwaj,Shikha
Fonte: Instituto de Tecnologia do Paraná - Tecpar Publicador: Instituto de Tecnologia do Paraná - Tecpar
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/2014 EN
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The aim of this work was to study the production of fibrinolytic protease by Bacillus subtilis I-2 on agricultural residues. Molasses substantially enhanced (63%) protease production (652.32 U/mL) than control (398.64 U/mL). Soybean meal supported maximum protease production (797.28 U/mL), followed by malt extract (770.1 U/mL), cotton cake (761.04 U/mL), gelatin (742.92 U/mL) and beef extract (724.8 U/mL). Based on the Plackett-Burman designed experiments, incubation time, soybean meal, mustard cake and molasses were identified as the significant fermentation parameters. Ammonium sulfate precipitation and DEAE sephadex chromatography resulted 4.8-fold purification of protease. Zymography showed the presence of three iso-forms in the partially purified protease preparation, which was confirmed by the SDS-PAGE analysis (42, 48, 60 kDa). Protease exhibited maximum activity at 50oC and at pH 8.0. Significant stability was observed at 30-50oC and at pH 7.0-10.0. Mg2+, Zn2+, Co2+, Ca2+, Mn2+ and Cu2+,EGTA, EDTA and aprotinin severely decreased the enzyme activity.

Production of xylanase and CMCase on solid state fermentation in different residues by Thermoascus aurantiacus miehe

Silva,Roberto da; Lago,Ellen S.; Merheb,Carolina W.; Macchione,Mariana M.; Park,Yong Kun; Gomes,Eleni
Fonte: Sociedade Brasileira de Microbiologia Publicador: Sociedade Brasileira de Microbiologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2005 EN
Relevância na Pesquisa
56.11%
The use of waste as raw material is important for government economy and natural balance. The purpose of this work was to study the production of CMCase and xylanase by a Brazilian strain of Thermoascus aurantiacus in solid state fermentation (SSF) using different agricultural residues (wheat bran, sugarcane bagasse, orange bagasse, corncob, green grass, dried grass, sawdust and corn straw) as substrates without enrichment of the medium and characterize the crude enzymes.The study of the extracellular cellulolytic and hemicellulolytic enzymes showed that T. arantiacus is more xylanolytic than cellulolytic. The highest levels of enzymes were produced in corncob, grasses and corn straw. All the enzymes were stable at room temperature by 24 h over a broad pH range (3.0-9.0) and also were stable at 60ºC for 1 h. The optimum pH and temperature for xylanase and CMCase were 5.0-5.5 and 5.0 and 75ºC, respectively. The microorganism grew quickly in stationary, simple and low cost medium. The secreted extracellular enzymes presented properties that match with those frequently required in industrial environment.

Hydrolysis of various thai agricultural biomasses using the crude enzyme from Aspergillus aculeatus iizuka FR60 isolated from soil

Boonmee,Atcha
Fonte: Sociedade Brasileira de Microbiologia Publicador: Sociedade Brasileira de Microbiologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2012 EN
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46.04%
In this study, forty-two fungi from soil were isolated and tested for their carboxymethyl cellulase (CMCase) and xylanase activities. From all isolates, the fungal isolate FR60, which was identified as Aspergillus aculeatus Iizuka, showed high activities in both CMCase and xylanase with 517 mU/mg protein and 550 mU/mg protein, respectively. The crude enzyme from A. aculeatus Iizuka FR60 could hydrolyze several agricultural residues such as corncob, and sweet sorghum leaf and stalk at comparable rates with respect to the tested commercial enzymes and with a maximum rate in rice hull hydrolysis (29 μg sugar g-1 dry weight substrate mg-1 enzyme hr-1). The highest amount of glucose was obtained from corncob by using the crude enzyme from A. aculeatus Iizuka FR60 (10.1 g/100 g dry substrate). From overall enzymatic treatment results, the lowest sugar yield was from rice hulls treatment (1.6 g/100 g dry weight) and the highest amount of reducing sugar was obtained from rice straw treatment (15.3 g/100 g dry weight). Among tested agricultural wastes, rice hull could not be effectively hydrolyzed by enzymes, whereas sugarcane leaf and stalk, and peanut shell could be effectively hydrolyzed (30-31% total sugar comparing with total sugar yield from acid treatment).

Glucose(xylose) isomerase production by Streptomyces sp. CH7 grown on agricultural residues

Chanitnun,Kankiya; Pinphanichakarn,Pairoh
Fonte: Sociedade Brasileira de Microbiologia Publicador: Sociedade Brasileira de Microbiologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2012 EN
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66.19%
Streptomyces sp. CH7 was found to efficiently produce glucose(xylose) isomerase when grown on either xylan or agricultural residues. This strain produced a glucose(xylose) isomerase activity of roughly 1.8 U/mg of protein when it was grown in medium containing 1% xylose as a carbon source. Maximal enzymatic activities of about 5 and 3 U/mg were obtained when 1% xylan and 2.5% corn husks were used, respectively. The enzyme was purified from a mycelial extract to 16-fold purity with only two consecutive column chromatography steps using Macro-prep DEAE and Sephacryl-300, respectively. The approximate molecular weight of the purified enzyme is 170 kDa, and it has four identical subunits of 43.6 kDa as estimated by SDS-PAGE. Its Km values for glucose and xylose were found to be 258.96 and 82.77 mM, respectively, and its Vmax values are 32.42 and 63.64 μM/min/mg, respectively. The purified enzyme is optimally active at 85ºC and pH 7.0. It is stable at pH 5.5-8.5 and at temperatures up to 60ºC after 30 min. These findings indicate that glucose(xylose) isomerase from Streptomyces sp. CH7 has the potential for industrial applications, especially for high-fructose syrup production and bioethanol fermentation from hemicellulosic hydrolysates by Saccharomyces cerevisiae.

Characterisation of Particulate Matter Emitted from Cofiring of Lignite and Agricultural Residues in a Fixed-Bed Combustor

Mantananont, Nattasut; Garivait, Savitri; Patumsawad, Suthum
Fonte: The Scientific World Journal Publicador: The Scientific World Journal
Tipo: Artigo de Revista Científica
Publicado em 02/05/2012 EN
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46.04%
This study is focused on the emission of fixed bed combustor batch operated. Real-time analyser ELPI (electrical low-pressure impactor) system was used to size-segregated particulate matter emission ranging from 40 nm to 10 μm. The results show that total number concentration were 3.4 × 103, 1.6 × 104, and 1.5 × 105 particles/cm3 · kgfuel, while total mass of particles were 12.2, 8.0, and 6.5 mg/Nm3 · kgfuel for combustion of lignite, rice husk and bagasse, respectively. But it can be noticed that cofiring released more particulate matter. Meanwhile it was found that the effect of ratio of over-fired air to total air supply is more pronounced, since decrease in this ratio, the amount of particles are decreased significantly. For particle size distribution, it can be observed that submicron-sized particles dominate and the most prevailing size is in the range: 50 nm

Glucose(xylose) isomerase production by Streptomyces sp. CH7 grown on agricultural residues

Chanitnun, Kankiya; Pinphanichakarn, Pairoh
Fonte: Sociedade Brasileira de Microbiologia Publicador: Sociedade Brasileira de Microbiologia
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
46.04%
Streptomyces sp. CH7 was found to efficiently produce glucose(xylose) isomerase when grown on either xylan or agricultural residues. This strain produced a glucose(xylose) isomerase activity of roughly 1.8 U/mg of protein when it was grown in medium containing 1% xylose as a carbon source. Maximal enzymatic activities of about 5 and 3 U/mg were obtained when 1% xylan and 2.5% corn husks were used, respectively. The enzyme was purified from a mycelial extract to 16-fold purity with only two consecutive column chromatography steps using Macro-prep DEAE and Sephacryl-300, respectively. The approximate molecular weight of the purified enzyme is 170 kDa, and it has four identical subunits of 43.6 kDa as estimated by SDS-PAGE. Its Km values for glucose and xylose were found to be 258.96 and 82.77 mM, respectively, and its Vmax values are 32.42 and 63.64 μM/min/mg, respectively. The purified enzyme is optimally active at 85°C and pH 7.0. It is stable at pH 5.5–8.5 and at temperatures up to 60°C after 30 min. These findings indicate that glucose(xylose) isomerase from Streptomyces sp. CH7 has the potential for industrial applications, especially for high-fructose syrup production and bioethanol fermentation from hemicellulosic hydrolysates by Saccharomyces cerevisiae.

China - Biomass Cogeneration Development Project : Fuel Supply Handbook for Biomass-Fired Power Projects

World Bank
Fonte: World Bank Publicador: World Bank
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This handbook provides an overview of the main topics that need consideration when managing the supply of biomass to large biomass power plants. It will help investors in China to develop, with assistance of local biomass supply experts, their own solutions. The focus is on biomass residues, in particular agricultural residues (mainly straw and stalks) and forestry residues (mainly residues from forestry operations). This handbook covers a wide range of topics related to biomass fuel supply risk in the planning and preparation stages for a biomass-fired power plant. Chapter two introduces the use of biomass as an energy source, including fuel selection considerations and the fuel standards and specifications required to match a particular fuel supply to a power generation system. Chapter three describes the use of biomass resource assessments at the project planning stage. Chapters four and five give insight into the biomass supply from straw and forestry residues, respectively. Finally, fuel supply management is covered in chapter six...

Transferring an Indigenous Practice for Soil Improvement : Cattle Manure with Groundnut Shells

World Bank
Fonte: Washington, DC Publicador: Washington, DC
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46.19%
Soil fertility never used to be a major constraint due to the age-old practices of recycling agricultural residues in several ways. However, in these days of inorganic fertilizers and quick returns, the problem of soil management and its related constraints are surfacing. In this context, indigenous practices related to soil and water conservation which can also be termed resource-conserving technologies need to be documented in a systematic way and also to be analyzed and introduced to potential new areas. Preparation of valuable manure from groundnut shells spread on the floor of the cattle shed is one such indigenous practice followed by farmers of Anantapur district in the state of Andhra Pradesh in India. This age-old practice is still practiced by the farmers of this region.

Decentralized Energy Services to Fight Poverty : Outcome Driven Engagement of Small and Medium-size Enterprises in the Provision of Energy Services in IDA Countries

World Bank
Fonte: Washington, DC Publicador: Washington, DC
EN_US
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46.11%
The Department for International Development (DFID)-Funded Energy Small and Medium Enterprises (SME) Program was created to support SMEs by helping countries unblock the factors that prevent their potential in the delivery of energy services. With thirteen energy projects in twelve countries and one regional program in Africa, the implementation of the program started considerably slower than expected but has demonstrated potential to make an impact in a relatively neglected area of delivering energy services to the poor. Lack of access to sufficient and sustainable supplies of energy affects as much as 90 percent of the population of many developing countries. Some 2 billion people are without electricity; a similar number remain dependent on fuels such as animal dung, crop residues, wood, and charcoal to cook their daily meals. Widespread inefficient production and use of traditional energy sources, such as fuel-wood and agricultural residues, pose economic, environmental, and health threats. Uneven distribution and use of modern energy sources, such as electricity, petroleum products, and liquefied or compressed natural gas, pose important issues of economics, equity, and quality of life. The Energy Sector Management Assistance Program (ESMAP) Energy SME program focused on off-grid electrification and biomass use as many communities and households that have yet to be electrified are relatively isolated...

Proceedings of the Workshop "Cereals Straw and Agricultural Residues for Bioenergy in European Union New Member States and Candidate Countries"

Fonte: OPOCE Publicador: OPOCE
Tipo: EUR - Scientific and Technical Research Reports Formato: Printed
ENG
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This document contains the Proceedings of the Workshop "Cereals straw and agricultural residues for bioenergy in New Member States and Candidate Countries" held in Novi Sad, Serbia on 2-3 October 2007. This Workshop was jointly organised by the Joint Research Centre ¿ Institute for Environment and Sustainability and University of Novi Sad, Faculty of Technical Sciences, and Academy of Sciences and Arts of Vojvodina, Serbia. The workshop addressed the availability and possible use of agricultural crop residues and especially of cereals straw for bioenergy production, status, problems and barriers for implementation, and perspectives for development in New Member States (NMS), Candidate Countries (CC) and Potential Candidate Countries (PCC). A better understanding of the situation on cereal straw and crop residues production and competitive use in NMS, CC and PCC was needed to assess their availability and potential for the use for energy production. The main topics addressed to 1) resources of cereal straw and agricultural residues, 2) environmental & agronomic constraints and 3) implementation issues.; JRC.H.8-Renewable energies

Baseline and Feasibility Assessment for Alternative Cooking Fuels in Senegal

Practical Action Consulting; Enda; World Bank
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Publications & Research :: Working Paper; Publications & Research
ENGLISH; EN_US
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This report was prepared by Practical Action Consulting for the Africa Clean Cooking Energy Solutions (ACCES) initiative of the World Bank. Most of Sub-Saharan Africa continues to rely overwhelmingly on traditional fuels and cooking technologies, both of which are a major cause of death and illness as well as a range of socio-economic and environmental problems. More than 90 per cent of the rural population of Senegal relies on solid fuels (charcoal and firewood in particular, but also dung and agricultural residues) to meet its household cooking needs. The primary objective of this study is, (a) to establish a baseline for the current level of penetration of four alternative cooking fuels in Senegal in a number of pre-identified regions, and (b) to assess the feasibility of adopting them in those regions. The four fuels are briquettes from charcoal dust and agricultural residues; ethanol, mainly from sugar cane residue (that is, molasses); pure plant oil (PPO) from locally grown, oil-bearing plants such as Jatropha curcas; and a household biogas system using mainly livestock waste. Against this background...

Advanced Biofuel Technologies : Status and Barriers

Cheng, Jay J.; Timilsina, Govinda R.
Fonte: Banco Mundial Publicador: Banco Mundial
Tipo: Publications & Research :: Policy Research Working Paper
ENGLISH
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46.11%
Large-scale production of crop based (first generation) biofuels may not be feasible without adversely affecting global food supply or encroaching on other important land uses. Because alternatives to liquid fossil fuels are important to develop in order to address greenhouse gas mitigation and other energy policy objectives, the potential for increased use of advanced (non-crop, second generation) biofuel production technologies has significant policy relevance. This study reviews the current status of several advanced biofuel technologies. Technically, it would be possible to produce a large portion of transportation fuels using advanced biofuel technologies, specifically those that can be grown using a small portion of the world's land area (for example, microalgae), or those grown on arable lands without affecting food supply (for example, agricultural residues). However, serious technical barriers limit the near-term commercial application of advanced biofuels technologies. Key technical barriers include low conversion efficiency from biomass to fuel...

Um sistema de informação para a análise multi-dimensional da actividade agrícola. Aplicação em diversos casos do panorama agrícola nacional; An information system for the multi-dimensional analysis of the agricultural activity - application in several cases of the national agricultural sector

Tristany, Miguel Nuno Guedes
Fonte: Universidade Técnica de Lisboa Publicador: Universidade Técnica de Lisboa
Tipo: Tese de Doutorado
Publicado em //2010 POR
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46.23%
Doutoramento em Engenharia Agronómica - Instituto Superior de Agronomia; In a globalised world that refuses progressively the externalization of any type of cost, especially environmental cost, it's urgent to look at the agricultural sector with a broad perspective, incorporating new decision variables and means of analysis. The agricultural activity is asked with increasing insistence to adapt to new tasks, respecting all types of demands directed to its production systems. This thesis involved the compilation of information on a broad spectrum of activities, resources and products, and the creation of a model that would allow a multi-dimensional analysis of the agricultural activities at national level, in order to respond to a possibly wide range of questions about economic and environmental performance, numerically or spatially. The case-studies presented, aimed at demonstrating the usefulness of the system in this multi-dimensional approach to agriculture, are four: analysis of suitability to irrigation of the Portuguese territory; technical and economical evaluation of land consolidation projects; the production of agricultural residues at national level; suitability of the Alqueva perimeter for several bioenergetic crops.

Agricultural residues for cellulolytic enzyme production by Aspergillus niger: effects of pretreatment

Salihu, Aliyu; Abbas, Olagunju; Sallau, Abdullahi Balarabe; Alam, Md. Zahangir
Fonte: Springer Berlin Heidelberg Publicador: Springer Berlin Heidelberg
Tipo: Artigo de Revista Científica
EN
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46.23%
Different agricultural residues were considered in this study for their ability to support cellulolytic enzyme production by Aspergillus niger. A total of eleven agricultural residues including finger millet hulls, sorghum hulls, soybean hulls, groundnut husk, banana peels, corn stalk, cassava peels, sugarcane bagasse, saw dust, rice straw and sheanut cake were subjected to three pretreatment (acid, alkali and oxidative) methods. All the residues supported the growth and production of cellulases by A. niger after 96 h of incubation. Maximum cellulase production was found in alkali-treated soybean hulls with CMCase, FPase and β-glucosidase yields of 9.91 ± 0.04, 6.20 ± 0.13 and 5.69 ± 0.29 U/g, respectively. Further studies in assessing the potential of soybean hulls are being considered to optimize the medium composition and process parameters for enhanced cellulase production.