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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Caracterização geoquímica e efeito térmico de intrusão de diabásio na matéria orgânica da Formação Irati, poço FP-12-SP, bacia do Paraná / Caracterização geoquímica e efeito térmico de intrusão de diabásio na matéria orgânica da Formação Irati, poço FP-12-SP, bacia do Paraná / Organic geochemistry characterization and thermal effect of diabase intrusions on organic matter of the Irati Formation, wel FP-12_SP, Bacia do Paraná / Organic geochemistry characterization and thermal effect of diabase intrusions on organic matter of the Irati Formation, wel FP-12_SP, Bacia do Paraná

Ingrid Alves Seifert 10 April 2013 (has links)
Agência Nacional do Petróleo / O estudo visou à caracterização geoquímica orgânica detalhada (carbono orgânico total, resíduo insolúvel, enxofre, pirólise Rock-Eval e biomarcadores) da Formação Irati através do furo pioneiro FP-12-SP localizado próximo da região de Anhembi (SP), e à análise das alterações destes parâmetros devido ao efeito térmico de intrusões de diabásio. A partir destes dados definiu-se 8 (oito) unidades quimioestratigráficas, determinou se o potencial gerador de cada unidade, o tipo de querogênio e a assinatura geoquímica através de parâmetros dos biomarcadores saturados e, por último, indicou-se as alterações causadas pelo efeito térmico de intrusivas nos sedimentos. O Membro Taquaral possui baixo teor de carbono orgânico total, querogênio tipo III/IV, com alta proporção de alcanos lineares e cicloalcanos, predominância dos esteranos C27 em relação ao C29, com indicações de ambiente marinho com salinidade normal. O Membro Assistência é caracterizado por apresentar valores de carbono orgânico total relativamente alto com aumento para o topo, intercalação de níveis siliciclásticos com carbonáticos, potencial gerador que chega a excelente e índice de hidrogênio predominante para óleo e condensado, baixa proporção de n-alcanos em relação aos cicloalcanos e alcanos ramificados, aparecimento do gamacerano, indicando ambiente marinho hipersalino com afogamento para o topo. O efeito térmico é visto a partir de 3 metros abaixo e 10 metros acima da soleira com maturação da matéria orgânica nos 9,5m mais próximos da soleira. A propagação de calor acima da soleira foi maior do que abaixo devido à diferença de condutividade térmica entre o carbonato e o folhelho, onde a máxima restrição com o aumento da salinidade na Unidade Quimioestratigráfica E, indicada pela presença de gamacerano, pode ter amplificado a passagem de calor para o topo. / The study aimed to detailed organic geochemistry characterization (total organic carbon, insoluble residue, sulfur , Rock-Eval pyrolysis and biomarkers) of the Irati Formation through pioneering well FP-12-SP located near the region of Anhembi (SP), and to analysis of changes in these parameters due to the thermal effect of diabase intrusions. From these data it was defined eight (8) chemostratigraphic units, as well as the potential generator of each unit, the type of kerogen and geochemical parameters through the saturated biomarkers, and, finally, it was indicated the changes caused by thermal effect of intrusives on sediments. The Taquaral Member has low content of total organic carbon, kerogen type III/IV, with a high proportion of linear alkanes and cycloalkanes, predominance of C27 steranes compared to C29, with indications of marine environment with normal salinity. The Member Assistência is characterized by relatively high levels of total organic carbon increasing to the top, interleaving siliciclastic levels with carbonate, generation potential reaching excellent and hydrogen index predominant to oil and condensate, low proportion of n-alkanes relative to cycloalkanes and branched alkanes and gammacerane indicating hypersaline marine environment with drowning to the top. The thermal effect is seen from 3 meters below and 10 meters above the sill with maturation of the organic matter at 9.5 m from the nearest sill. The propagation of heat above the threshold was higher than below due to difference in thermal conductivity between the shale and carbonate, where the maximum constraint with increasing salinity in Chemostratigraphic Unit E, indicated by the presence of gammacerane, may have amplified the passage of heat to the top.
42

Growth of filamentous fungi in pure olive oil : a fundamental study for application to vegetable oil-derived waste streams

Nazir, Tahir Muhammad January 2020 (has links)
Vegetable oil is more difficult to degrade by microorganisms in comparison to carbohydrates and protein. Thus, it creates serious environmental and health concerns if oil-derived waste streams produced by restaurants and industries remain untreated. In this study, a strategy has been developed to grow filamentous fungi in pure olive oil so that it can be used as a bench-mark for growth in olive oil mill sidestreams. The growth of different strains (Aspergillus oryzae, Neurospora intermedia and Rhizopus oryzae) was tested in pure olive oil. A pre-germination stage using glucose as carbon and energy source, or the addition of yeast extract, were found necessary for successful fungal growth in olive oil. Here, A. oryzae showed a superior performance in comparison to N. intermedia and R. oryzae. Medium pH did not impact A. oryzae growth in olive oil, whereas a concentration higher than 40 g/L of the latter impaired the growth of the ascomycete. Obtained biomasses from A. oryzae and N. intermedia cultivations in olive oil were analyzed and compared for protein, fat, ash, and alkali-insoluble material (cell wall content), where the presence of olive oil had a steering effect. The fungal biomass of A. oryzae, obtained from cultivation in the absence of olive oil, contained 0.33% fat and 48% protein, whereas the respective values in the presence of olive oil were 31% and 14%. Similar trends on fat and protein contents were observed for the biomass of N. intermedia. Sudan black staining was also performed on fresh biomass which clearly indicated the presence of oil globules inside the fungal cells. This research can be a fundamental step towards treatment of oil-based waste streams, which entails high-energy and costs if treated, or environmental impacts during informal discharges. Moreover, the fact that the composition of fungal biomass can be steered through addition of olive oil increases the versatility of the originated biomass for various applications, namely in feed, food and biofuel production.
43

Microbial Cell Disruption Using Pressurized Gases to Improve Lipid Recovery from Wet Biomass: Thermodynamic Analysis

Howlader, Md Shamim 04 May 2018 (has links)
Microbial cell disruption using pressurized gas is a promising approach to improve the lipid extraction yield directly from the wet biomass by eliminating the energy-intensive drying process, which is an integral part of traditional methods. As the process starts with the solubilization of the gas in lipid-rich microbial cells, it is important to understand the solubility of different potential gases in both lipid (triglyceride) and lipid-rich microbial cell culture to design efficient cell disruption processes. In this study, we determined the solubility of different gases (e.g., CO2, CH4, N2, and Ar) in canola oil (triglyceride) using a pressure drop gas apparatus developed in our laboratory. The solubility of different gases in triglyceride followed the trend CO2 > CH4 > Ar > N2. Since the solubility of CO2 was found to be higher compared to other gases, the solubility of CO2 in lipid rich cell culture, cell culture media, and spent media was also determined. It was found that CO2 is more soluble in triglycerides, but less soluble in lipid-rich cell culture compared to CO2 in water. From both thermodynamic models and Monte Carlo simulations, the correlated solubility was found to be in good agreement with the experimental results. CO2 was found to be the most suitable gas for microbial cell disruption because almost 100% cell death occurred when using CO2 whereas more than 85% cells were found to be active after treatment with CH4, N2, and Ar. The optimization of microbial cell disruption was conducted using the combination of Box-Behnken design of experiment (DOE) technique and response surface methodology. The optimized cell disruption conditions were found to be 3900 kPa, 296.5 K, 360 min, and 325 rpm where almost 100% cell death was predicted from the statistical modeling. Finally, it was found that 86% of the total lipid content can be recovered from the wet biomass after treatment with pressurized CO2 under optimized conditions compared to control where up to 74% of the total lipid content can be recovered resulting in 12% increase in the lipid extraction yield using pressurized CO2.
44

Pyrolysis Strategies for Effective Utilization of Lignocellulosic and Algal Biomass

Maddi, Balakrishna January 2014 (has links)
No description available.
45

Crescimento e qualidade de mudas de Pinhão Manso (Jatropha curcas L.) produzidas em ambiente protegido / Growth and quality of Physic Nut seedlings (Jatropha curcas L.) produced in greenhouse

Paulino, Janaina 22 January 2010 (has links)
Com a implantação do Plano Nacional de Produção de Biodiesel, surgiu o interesse na produção comercial de Pinhão Manso (Jatropha curcas L.), uma vez que essa oleaginosa apresenta características favoráveis para a produção do biodiesel. Informações sobre essa cultura ainda são escassas, principalmente no Brasil onde a pouco tempo iniciaram-se as pesquisas. A necessidade de informações locais também ressalta a importância da pesquisa com o Pinhão Manso, sendo que muito se comenta sobre a adaptabilidade dessa cultura sob diferentes condições. Com base nessas necessidades, no desenvolvimento deste experimento teve-se como objetivo avaliar o crescimento e a qualidade de mudas de Pinhão Manso produzidas em casa de vegetação até o momento de serem transplantadas para o campo, para isto foram proporcionadas diversas maneiras de produção, envolvendo diferentes tipos e volumes de recipientes, substratos e adubações, além de contabilizar a quantidade de água consumida pelas mudas para os diferentes recipientes e substratos durante a fase experimental. Conclui-se que as mudas que apresentaram melhor qualidade e que proporcionaram maior crescimento, obtendo condições adequadas para o transplantio na sexta semana após a emergência, foram obtidas com a combinação dos fatores: substrato comercial Plantmax®, recipiente tipo tubete com volume de 290 cm3 e o adubo de liberação lenta, Osmocote®. A combinação do substrato Plantmax® e o tubete de 290 cm3 proporcionaram um consumo de água de aproximadamente 1,4 L contabilizado a partir da emergência das mudas. / With the settlement of the National Plan of Biofuel Production, the interest aroused in the commercial production of Physic Nut (Jatropha curcas L.), once that oleaginous plant presents favorable characteristics for Biofuel production. Information on that crop is still scarce, mainly in Brazil where research is incipient. The need of information on local conditions also emphasizes the importance of research on Physic Nut, once much is commented on the adaptability of that crop to different conditions, but a few experiments to evaluate it have been performed. Therefore, during the development of this experiment we aimed to evaluate growth and quality of Physic Nut seedlings produced in greenhouse until the moment to be transplanted to the field. To do so, several production ways were analyzed, involving different types and volumes of dibble-tube containers, different substrate and fertilization. Besides, it was measured the amount of water consumed by the seedlings for different containers and substrate during the experimental phase. Results show that seedlings that presented best quality and largest growth, obtaining appropriate conditions to transplantation in the sixth week after germination, were obtained from the combination of the following factors: commercial substrate Plantmax®, dibble-tube container with volume of 290 cm3 and fertilizer of slow liberation, Osmocote®. The combination of the substrate Plantmax® and the dibble-tube container of 290 cm3 provided a consumption of water of approximately 1.4 L counted since the beginning of seedlings emergence.
46

Crescimento e qualidade de mudas de Pinhão Manso (Jatropha curcas L.) produzidas em ambiente protegido / Growth and quality of Physic Nut seedlings (Jatropha curcas L.) produced in greenhouse

Janaina Paulino 22 January 2010 (has links)
Com a implantação do Plano Nacional de Produção de Biodiesel, surgiu o interesse na produção comercial de Pinhão Manso (Jatropha curcas L.), uma vez que essa oleaginosa apresenta características favoráveis para a produção do biodiesel. Informações sobre essa cultura ainda são escassas, principalmente no Brasil onde a pouco tempo iniciaram-se as pesquisas. A necessidade de informações locais também ressalta a importância da pesquisa com o Pinhão Manso, sendo que muito se comenta sobre a adaptabilidade dessa cultura sob diferentes condições. Com base nessas necessidades, no desenvolvimento deste experimento teve-se como objetivo avaliar o crescimento e a qualidade de mudas de Pinhão Manso produzidas em casa de vegetação até o momento de serem transplantadas para o campo, para isto foram proporcionadas diversas maneiras de produção, envolvendo diferentes tipos e volumes de recipientes, substratos e adubações, além de contabilizar a quantidade de água consumida pelas mudas para os diferentes recipientes e substratos durante a fase experimental. Conclui-se que as mudas que apresentaram melhor qualidade e que proporcionaram maior crescimento, obtendo condições adequadas para o transplantio na sexta semana após a emergência, foram obtidas com a combinação dos fatores: substrato comercial Plantmax®, recipiente tipo tubete com volume de 290 cm3 e o adubo de liberação lenta, Osmocote®. A combinação do substrato Plantmax® e o tubete de 290 cm3 proporcionaram um consumo de água de aproximadamente 1,4 L contabilizado a partir da emergência das mudas. / With the settlement of the National Plan of Biofuel Production, the interest aroused in the commercial production of Physic Nut (Jatropha curcas L.), once that oleaginous plant presents favorable characteristics for Biofuel production. Information on that crop is still scarce, mainly in Brazil where research is incipient. The need of information on local conditions also emphasizes the importance of research on Physic Nut, once much is commented on the adaptability of that crop to different conditions, but a few experiments to evaluate it have been performed. Therefore, during the development of this experiment we aimed to evaluate growth and quality of Physic Nut seedlings produced in greenhouse until the moment to be transplanted to the field. To do so, several production ways were analyzed, involving different types and volumes of dibble-tube containers, different substrate and fertilization. Besides, it was measured the amount of water consumed by the seedlings for different containers and substrate during the experimental phase. Results show that seedlings that presented best quality and largest growth, obtaining appropriate conditions to transplantation in the sixth week after germination, were obtained from the combination of the following factors: commercial substrate Plantmax®, dibble-tube container with volume of 290 cm3 and fertilizer of slow liberation, Osmocote®. The combination of the substrate Plantmax® and the dibble-tube container of 290 cm3 provided a consumption of water of approximately 1.4 L counted since the beginning of seedlings emergence.
47

Caracterização e propriedades funcionais de óleos extraídos de castanhas e nozes /

Costa, Tainara. January 2011 (has links)
Orientador: Neuza Jorge / Banca: Sabria Aued Pimentel / Banca: Agdamar Affini Suffredini / Resumo: Estudos epidemiológicos têm demonstrado uma relação inversa entre a ingestão de castanhas e nozes e as doenças crônicas tais como doenças cardiovasculares e câncer. As castanhas e nozes possuem ácidos fenólicos e flavonoides, além de serem ricas em tocoferóis, fitosteróis e esqualeno. São fontes de carboidratos, ácidos graxos essenciais e minerais. Os possíveis efeitos benéficos destes compostos se devem à sua atividade antioxidante e antiproliferativa. Desta forma, o presente trabalho teve como objetivo caracterizar os óleos extraídos de castanhas e nozes a fim de identificar compostos bioativos benéficos para aplicação destes óleos especiais em alimentos. Foi realizada a determinação da composição centesimal de castanhas do Brasil (Bertholletia excelsa), Sapucaia (Lecythis pisonis), Cotia (Couepia edulis) e Gurguéia (Dipteryx lacunifera) e das nozes Pecã (Carya illinoensis) e Noz (Juglans regia). Os óleos extraídos das castanhas e nozes foram analisados quanto à caracterização físico-química (teor de ácidos graxos livres, índice de acidez, de peróxidos, de iodo, de refração, índice de saponificação, matéria insaponificável e estabilidade oxidativa), composição em ácidos graxos, tocoferóis e compostos fenólicos totais. Os resultados foram submetidos a análises de variância e testes de Tukey para médias a 5%, empregando o programa ESTAT versão 2.0. Pelos resultados, verificou-se que as castanhas e nozes estudadas possuem composição centesimal distinta, porém constituíram fontes significativas de lipídios (35,74-68,89%), sendo uma fonte alternativa para óleos vegetais comestíveis. As propriedades físico-químicas dos óleos extraídos das castanhas e nozes foram comparáveis às de óleos convencionais de boa qualidade, além de possuírem como ácidos graxos majoritários o palmítico, o esteárico, o oleico e o linoleico... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Epidemiological studies have proved an inverse relationship between the intake of nuts and the development of chronic illnesses such as cardiovascular disease and cancers. Nuts have phenolic acids and flavonoids, in addition to being rich in tocopherols, phytosterols and squalene. They are sources of carbohydrates, essential fatty acids and minerals. The possible beneficial effects of these compounds are due to their antioxidant and anti-proliferative activity. This study had as its objective to characterize the oils extracted from nuts to identify the beneficial bioactive compounds to the application of these oils in foods. Tests were conducted to determine the centesimal composition of Brazil nuts (Bertholletia excelsa), Sapucaia nuts (Lecythis pisonis), Cotia nuts (Couepia edulis) Gurguéia nuts (Dipteryx lacunifera), Pecan nuts (Carya illinoensis) and Walnuts (Juglans regia). The oils extracted from the nuts were analyzed to determine their physical-chemical characterization (content of free fatty acids, acid value, peroxide value, iodine value, refractive index, saponification value, unsaponifiable matter and oxidative stability), their composition of fatty acids, tocopherols, and total phenolic compound content. The results were submitted to analysis of variance and Turkey's range test for averages of 5% using the ESTAT program version 2.0. From the results, it was verified that the nuts studied had distinct centesimal compositions, but all constituted significant sources of lipids (35.74-68.89%), these oils being an alternative source of edible vegetable oils. The physical-chemical properties of the oils extracted from the nuts were comparable to the conventional oils of good quality; in addition they also have in their composition the majority of their fatty acids as palmitic, stearic, oleic and linoleic, amounting to 87-99% of the total. With regard to the content... (Complete abstract click electronic access below) / Mestre
48

Cultivo do girassol irrigado sob diferentes lâminas de água e doses de nitrogênio / Sunflower cultivation irrigated under different water blades and nitrogen doses

Freire, Jonas de Oliveira 29 August 2016 (has links)
Submitted by Lara Oliveira (lara@ufersa.edu.br) on 2017-02-14T19:11:01Z No. of bitstreams: 1 JonasOF_TESE.pdf: 3319263 bytes, checksum: 51b79bea8bd5a5a042d4db215bfe1a86 (MD5) / Approved for entry into archive by Socorro Pontes (socorrop@ufersa.edu.br) on 2017-02-15T14:50:14Z (GMT) No. of bitstreams: 1 JonasOF_TESE.pdf: 3319263 bytes, checksum: 51b79bea8bd5a5a042d4db215bfe1a86 (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2017-02-15T14:52:02Z (GMT) No. of bitstreams: 1 JonasOF_TESE.pdf: 3319263 bytes, checksum: 51b79bea8bd5a5a042d4db215bfe1a86 (MD5) / Made available in DSpace on 2017-03-21T14:53:47Z (GMT). No. of bitstreams: 1 JonasOF_TESE.pdf: 3319263 bytes, checksum: 51b79bea8bd5a5a042d4db215bfe1a86 (MD5) Previous issue date: 2016-08-29 / Sunflower adapts to different conditions of climate and soil, including the prevailing climate in the Northeast, but the water needs, as well as nitrogen fertilizer recommendations are not yet fully defined. The objective of this study was to evaluate sunflower productivity and efficiency of water and nitrogen use. The experiment was conducted between October 2013 to January 2014 in Unidade Agrícola Industrial Escola do Instituto Federal de Educação, Ciência e Tecnologia do Rio Grande do Norte (IFRN/Campus Apodi), Apodi, in the state of Rio Grande do Norte, Brazil. Statistical design used was in blocks in the 4 x 4 factorial scheme with four replications. The treatments consisted of four water slides 58, 80, 100 and 120% of crop evapotranspiration (ETc) associated with four doses of nitrogen 40, 100, 200 and 370% of the dose recommended for the cultivation of 70 kg ha-1. The depth water of 517 mm (108% ETc) associated with nitrogen dose of 77 kg ha-1 provided 91.3% of the maximum productivity, these being the doses recommended in the studied conditions. The oil productivity depending on depths water and nitrogen levels followed the trend surface function in oil yield of water depths and doses of nitrogen. The water factor was most limiting characteristics evaluated the nitrogen fertilization / O girassol se adapta a diferentes condições de clima e solo, inclusive ao clima predominante na Região Nordeste, porém, as necessidades hídricas, assim como as recomendações de adubação nitrogenada, ainda não estão perfeitamente definidas. Objetivouse com o presente estudo, avaliar a produtividade do girassol e a eficiência do uso da água e nitrogênio. O experimento foi conduzido no período de 29 outubro de 2013 a janeiro de 2014 na Unidade Agrícola Industrial Escola do Instituto Federal de Educação, Ciência e Tecnologia do Rio Grande do Norte (IFRN/Campus Apodi), Apodi, RN. O delineamento estatístico adotado foi em blocos no esquema fatorial 4 x 4 com quatro repetições. Os tratamentos consistiram em quatro lâminas de irrigação 58, 80, 100 e 120% da evapotranspiração da cultura (ETc) associadas a quatro doses de nitrogênio 40, 100, 200 e 370% da dose padrão de 70 kg ha- 1. A lâmina de água de 517 mm (108% da ETc) associada a dose nitrogenada de 77 kg ha-1 proporcionou 91,3% da produtividade máxima de grãos, sendo estas as doses recomendadas nas condições estudadas. A produtividade de óleo em função das doses de água e nitrogênio acompanhou a tendência da superfície do rendimento de óleo em função das lâminas de água e doses de nitrogênio. As lâminas de água foram mais limitantes às características avaliadas que a adubação nitrogenada / 2017-02-14
49

Caracterização e propriedades funcionais de óleos extraídos de castanhas e nozes

Costa, Tainara [UNESP] 25 February 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-25Bitstream added on 2014-06-13T20:50:18Z : No. of bitstreams: 1 costa_t_me_sjrp_parcial.pdf: 47814 bytes, checksum: 6c1a8276e877be23955b7f93345300f0 (MD5) Bitstreams deleted on 2015-08-28T16:08:58Z: costa_t_me_sjrp_parcial.pdf,. Added 1 bitstream(s) on 2015-08-28T16:10:00Z : No. of bitstreams: 1 000640583.pdf: 746185 bytes, checksum: 16347c250c43b09d0103a7481f5b4d4d (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Estudos epidemiológicos têm demonstrado uma relação inversa entre a ingestão de castanhas e nozes e as doenças crônicas tais como doenças cardiovasculares e câncer. As castanhas e nozes possuem ácidos fenólicos e flavonoides, além de serem ricas em tocoferóis, fitosteróis e esqualeno. São fontes de carboidratos, ácidos graxos essenciais e minerais. Os possíveis efeitos benéficos destes compostos se devem à sua atividade antioxidante e antiproliferativa. Desta forma, o presente trabalho teve como objetivo caracterizar os óleos extraídos de castanhas e nozes a fim de identificar compostos bioativos benéficos para aplicação destes óleos especiais em alimentos. Foi realizada a determinação da composição centesimal de castanhas do Brasil (Bertholletia excelsa), Sapucaia (Lecythis pisonis), Cotia (Couepia edulis) e Gurguéia (Dipteryx lacunifera) e das nozes Pecã (Carya illinoensis) e Noz (Juglans regia). Os óleos extraídos das castanhas e nozes foram analisados quanto à caracterização físico-química (teor de ácidos graxos livres, índice de acidez, de peróxidos, de iodo, de refração, índice de saponificação, matéria insaponificável e estabilidade oxidativa), composição em ácidos graxos, tocoferóis e compostos fenólicos totais. Os resultados foram submetidos a análises de variância e testes de Tukey para médias a 5%, empregando o programa ESTAT versão 2.0. Pelos resultados, verificou-se que as castanhas e nozes estudadas possuem composição centesimal distinta, porém constituíram fontes significativas de lipídios (35,74-68,89%), sendo uma fonte alternativa para óleos vegetais comestíveis. As propriedades físico-químicas dos óleos extraídos das castanhas e nozes foram comparáveis às de óleos convencionais de boa qualidade, além de possuírem como ácidos graxos majoritários o palmítico, o esteárico, o oleico e o linoleico... / Epidemiological studies have proved an inverse relationship between the intake of nuts and the development of chronic illnesses such as cardiovascular disease and cancers. Nuts have phenolic acids and flavonoids, in addition to being rich in tocopherols, phytosterols and squalene. They are sources of carbohydrates, essential fatty acids and minerals. The possible beneficial effects of these compounds are due to their antioxidant and anti-proliferative activity. This study had as its objective to characterize the oils extracted from nuts to identify the beneficial bioactive compounds to the application of these oils in foods. Tests were conducted to determine the centesimal composition of Brazil nuts (Bertholletia excelsa), Sapucaia nuts (Lecythis pisonis), Cotia nuts (Couepia edulis) Gurguéia nuts (Dipteryx lacunifera), Pecan nuts (Carya illinoensis) and Walnuts (Juglans regia). The oils extracted from the nuts were analyzed to determine their physical-chemical characterization (content of free fatty acids, acid value, peroxide value, iodine value, refractive index, saponification value, unsaponifiable matter and oxidative stability), their composition of fatty acids, tocopherols, and total phenolic compound content. The results were submitted to analysis of variance and Turkey’s range test for averages of 5% using the ESTAT program version 2.0. From the results, it was verified that the nuts studied had distinct centesimal compositions, but all constituted significant sources of lipids (35.74-68.89%), these oils being an alternative source of edible vegetable oils. The physical-chemical properties of the oils extracted from the nuts were comparable to the conventional oils of good quality; in addition they also have in their composition the majority of their fatty acids as palmitic, stearic, oleic and linoleic, amounting to 87-99% of the total. With regard to the content... (Complete abstract click electronic access below)
50

Implication du métabolisme carboné pour une production différentielle d'huile chez les plantes oléagineuses-Lin : modélisation des systèmes / Involvement of carbon metabolism for a differential oil production by oleaginous plants-Lin : systems modeling

Acket, Sébastien 09 January 2015 (has links)
Les graines de lin sont composées de teneurs élevées en huile (45 g d’huile/100g MS) stockées sous forme de triglycérides dans l’embryon (Venglat et al., 2011). Ces huiles hautement insaturées sont utilisées depuis de nombreuses années pour des applications industrielles (vernis, linoleum…). Toutefois, ces huiles riches en oméga-3 présentent également une grande importance pour la santé humaine. Pour cette raison, l’industrie alimentaire est particulièrement intéressée pour développer des produits enrichis en huile de lin. Pour répondre à cette demande, il est nécessaire de sélectionner des cultivars accumulant plus d’huile. Afin de sélectionner efficacement de telles plantes, il est nécessaire d'acquérir des connaissances sur les mécanismes de synthèse, d’accumulation et de régulation des huiles dans les graines oléagineuses (Sharma et Chauhan 2012). Pour comprendre les accumulations des huiles dans les graines de lin et leurs régulations, deux lignées de lin ayant des teneurs en huile différent ont été sélectionnées (Astral : 44,6 ± 0,2 g d’huile/100g MS ; 238 : 37,0 ± 0,7 g d’huile/100g MS). Dans ce travail, nous avons déterminé les différences d’accumulation des composées de la graines entre les deux lignées dans les embryons, les téguments, la différence d’expression des gènes dans ces embryons et ces téguments, et analyser les flux métaboliques dans les embryons des deux lignées de lin durant la synthèse des acides gras. Ces études ont montré : (i) que les embryons de lin Astral qui accumule plus d’huile dans ses embryons accumule moins de protéines dans les embryons, (ii) que les téguments de lin Astral accumule moins de proanthocyanidines et de protéines que dans les téguments de la lignée 238, (iii) qu’aucun lien avec l’accumulation différente en huile dans les embryons et la différence d’accumulation dans les téguments n’a pu être mis en évidence, (iii) que le glucose est le précurseur carboné permettant la synthèse des acides gras, (iv) que le flux de carbone permettant la synthèse des acides gras passe majoritairement par la glycolyse cytosolique jusqu’au PEP cytosolique qui est transporté dans le plaste pour être convertie en pruvate puis acétylCoA, précurseur de la synthèse des acides gras, (v) que le flux permettant la synthèse de G3P est 29 fois plus élevée que dans les embryons de lin 238 que dans les embryons de lin Astral, (vi) : que la surexpression du gène codant pour la DHAP synthase (genolin_c54022 317) et la G3PDH (genolin_c10324 594) dans les embryons de la lignée Astral/238, pourraient induire une synthèse plus importante de G3P nécessaire à la formation des triglycérides. / Flax seeds are composed oh high levels of oil (45 g oil / 100 g DM) stored as triglycerides in their embryos (Venglat et al., 2011). These highly unsatured oils have been used for many years for industrial applications (varnish, linoleum,...). However, these oils rich in omega-3 are also a great importance to human health. for this reason, the food industry is particularly interesed to develop innovative products enriched in linseed oil. To meet these requirements, it is necessary to develop linseed cultivars that accumulate more oils. In order to select such plants, it is necessary to acquire knowledge on mechanisms, accumulation and regulation of oils synthesis in oilseeds (Sharma and Chauhan, 2012). To better understand oil accumulation in flaxseed, two linseed genotypes presenting different level in oil content were selected (Astral : 44,6 ± 0,2 g oil / 100 MS ; 238 : 37,0 ± 0,7 g oil / 100 g DM). In this work, we determined the differences in accumulation between the two lines in embryos, integumen, the difference in gene expression in the embryos and the integument, and we analysed the metabolic flux in the embryos of both flax lines during the synthesis of fatty acids. These studies have shown : (i) the flax embryos Astral accumulates more oil in its embryo accumulates less protein in embryos, (ii) that the Astal flax husks accumulates less proanthocyanidins and proteins in teguments of the line 238, (iii) no link with the different oil accumumation in embryos and the difference in accumulation the integument could be demonstrated, (iv) that the glucose is the carbon precursor for the synthesis of fatty acids, (v) thet the flow of carbon to the synthesis of fatty acids predominantly through cytosolic glycolysis to PEP cytosolic, that is transported into the plastic for conversion to pruvate then acetylCoA, precursor synthesis of fatty acids, (vi) the flow for the synthesis of G3P in Astral embryos is 29 times higher than in the 238 embryos, (vii) the overexpression of the gene encoding the DHAP synthase (genolin_c54022 317) and G3PDH (genolin-c10324 594) in embryos of the Astral / 238, could induce a higher synthesis G3P necessary for the triglycerides.

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