190 resultados para JATROPHA CURCAS


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Pós-graduação em Biologia Animal - IBILCE

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Access to affordable and renewable sources of energy is crucial to reducing poverty and enhancing rural development in countries of the global South. Straight vegetable oil was recently identified as a possible alternative to conventional biomass for rural energy supply. In this context, the Jatropha curcas Linn. species has been extensively investigated with regard to its potential as a biofuel feedstock. In contrast, only little is known about Jatropha mahafalensis Jum. & H. Perrier, which is an indigenous and endemic representative of the Jatropha genus in Madagascar. This paper explores the potential and suitability of J. mahafalensis as a biofuel feedstock. Seed samples were collected in the area of Soalara in south-western Madagascar in February and September 2011. Two agro-ecological zones (coastal area and calcareous plateau) and two plant age groups (below and above 10 years) were considered. These four sample groups were analyzed with regard to oil properties, element contents, and fatty acid profiles. Measured values differed greatly between the two harvests, probably owing to different climatic or storage conditions. No direct relation between age of trees or location and oil quality could be established. The analyses indicate that J. mahafalensis oil can be used in oil lamps, cooking stoves and stationary combustion engines for electrification or for biodiesel production. However, modifications in storage and extraction methods, as well as further processing steps are necessary to enable its utilization as a straight vegetable oil and feedstock for biodiesel production. If these technical requirements can be met, and if it turns out that J. mahafalensis oil is economically competitive in comparison with firewood, charcoal, paraffin and petroleum, it can be considered as a promising feedstock for rural energy supply.

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In many parts of the eastern African region wood-based fuels will remain dominant sources of energy in coming decades. Pressure on forests, especially in semi-arid areas will therefore continue increasing. In this context, the role of liquid biofuels as substitutes for firewood and charcoal, to help reducing pressure on woody biomass and contributing to a better energy security of rural communities, has remained controversial among researchers and practitioners. At household level, the economic and technical feasibility of straight vegetable oil (SVO) was assessed mainly on Jatropha curcas, with unpersuasive results. So far nothing is known about the suitability as an energy carrier of Jatropha mahafalensis Jum. & H. Perrier, the only endemic representative of the Jatropha genus in Madagascar. This paper explores the potential of this plant as a biofuel feedstock in the agro-pastoral area of Soalara, in the semi-arid south-western part of Madagascar. Only hedge-based production was considered to rule out competition over land with food crops. Yield data, the length of currently existing hedges and energy consumption patterns of households were used to assess the quantitative potential and economic viability of J. mahafalensis SVO for lighting and cooking. Tests were conducted with cooking and lighting devices to assess their technical suitability at household level. The paper concludes that J. mahafalensis hedges have some potential to replace paraffin for lighting (though without much economic benefit for the concerned households), but not to replace charcoal or firewood for cooking. The paper recommends that rural energy strategies in similar contexts do not focus only on substituting current fuels with SVO, but should also take into consideration other alternatives. In the case of cooking, there seems to be substantially more potential in increasing the efficiency of current fuel production and consumption technologies (kilns and stoves); and in the case of lighting, solutions based on SVO need to be compared against other options such as portable solar devices.

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Doutoramento em Engenharia dos Biossistemas - Instituto Superior de Agronomia - UL

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The objective of this research is to produce alternative food sources of protein by optimizing the potential of jatropha curcas which is agroindustry waste. This study is planned in two years and is a series of jatropha seed exploration through fermentation using Lactobacillus acidophilus. Specific targets in the first year of study were to assess the optimization of the fermentation process by supplementing the source of N soybean meal and fish meal. Experiments using Completely Randomized Design (RAL) factorial pattern with first factor was supplementation (F) and second factor was incubation time (W), fermentation optimization consisted of: F1 (F0 + 2.5% soybean meal flour), F2 (F0 + 2.5% fish meal), F3 (F1 + 0.45% Dicalsium Phosphat) and F4 (F2 + 0.45% Dicalsium Phosphat). The incubation time is differentiated W1: 3 days, W2: 5 days and W3: 7 days. It can be concluded that: dry matter, gross energy, calcium and phospor are influenced by interaction between type of supplementation of source of N + DCP with fermentation time, whereas fat content is only influenced by fermentation time with optimal time decrease of fat content is 5,92 days. Total protein and amino acid levels are only influenced by different types of supplementation. Phorbolester antinutrition levels are influenced by the duration of the fermentation.  Based on antinutritive as a limiting factor. F4W5 is the best treatment and can used as a feed ingredient.

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Biodiesel is a renewable fuel that has been shown to reduce many exhaust emissions, except oxides of nitrogen (NOx), in diesel engine cars. This is of special concern in inner urban areas that are subject to strict environmental regulations, such as EURO norms. Also, the use of pure biodiesel (B100) is inhibited because of its higher NOx emissions compared to petroleum diesel fuel. The aim of this present work is to investigate the effect of the iodine value and cetane number of various biodiesel fuels obtained from different feed stocks on the combustion and NOx emission characteristics of a direct injection (DI) diesel engine. The biodiesel fuels were chosen from various feed stocks such as coconut, palm kernel, mahua (Madhuca indica), pongamia pinnata, jatropha curcas, rice bran, and sesame seed oils. The experimental results show an approximately linear relationship between iodine value and NOx emissions. The biodiesels obtained from coconut and palm kernel showed lower NOx levels than diesel, but other biodiesels showed an increase in NOx. It was observed that the nature of the fatty acids of the biodiesel fuels had a significant influence on the NOx emissions. Also, the cetane numbers of the biodiesel fuels are affected both premixed combustion and the combustion rate, which further affected the amount of NOx formation. It was concluded that NOx emissions are influenced by many parameters of biodiesel fuels, particularly the iodine value and cetane number.

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Research on alternative fuel for the vehemently growing number of automotivesis intensified due to environmental reasons rather than turmoil in energy price and supply. From the policy and steps to emphasis the use of biofuel by governments all around the world, this can be comprehended that biofuel have placed itself as a number one substitute for fossil fuels. These phenomena made Southeast Asia a prominent exporter of biodiesel. But thrust in biodiesel production from oilseeds of palm and Jatropha curcas in Malaysia, Indonesia and Thailand is seriously threatening environmental harmony. This paper focuses on this critical issue of biodiesels environmental impacts, policy, standardization of this region as well as on the emission of biodiesel in automotive uses. To draw a bottom line on feasibilities of different feedstock of biodiesel, a critical analysis on oilseed yield rate, land use, engine emissions and oxidation stability is reviewed. Palm oil based biodiesel is clearly ahead in all these aspects of feasibility, except in the case of NOx where it lags from conventional petro diesel.

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Biofuels are under discussion all over the world today. There are fears that the farming of biofuel plants hurts food production and weakens the food security of the poor. On the other hand, biofuel production could lessen the green house gas emissions caused by transportation, and it could also spread the profits from fuel markets more evenly between countries. The aim of this thesis is to find out how an oil plant called jatropha curcas L., which is used for biodiesel production, can affect the sustainability of livelihoods in Vietnam from the point of view of land use. Special attention is given to the effects of jatropha farming on food production, land productivity, natural resources of livelihoods and global livelihood. Jatropha belongs to the family Euphorbiaceae, and it grows naturally in tropical and subtropical areas. It can be grown on poor soils, its seeds have high oil content, and it cannot be eaten due to its toxicity. The plant grows naturally in Vietnam, and during the past few years it has also begun to be farmed for making biodiesel. Population growth in Vietnam has slowed down, but the population's standard of living and energy consumption are still rising quickly. An interest in the international biodiesel markets has awoken following Vietnam's opening up to international trade. Jatropha diesel plays a significant part in Vietnam’s clean fuel strategy, and many companies have set up jatropha plantations to produce raw material for biodiesel. Diesel made from jatropha is planned to be used both locally and for export. This thesis uses a theoretical concept of sustainable livelihoods. According to the theory, the resources that people have shape their livelihood possibilities. Farming of jatropha affects the livelihoods of people especially through land use, as land use changes have effects on many of the livelihood resources. In addition to the written sources, the material of the thesis is based on 14 interviews in Vietnam and Finland, and on observation during a field trip to Northern Vietnam in the spring of 2008. The results of the thesis show that jatropha diesel can support the sustainability of livelihoods at different scales if it is produced with deliberation. However, positive results are only possible if decisions are made carefully and more experience is collected. The possibilities of sustainable jatropha farming depend mainly on the previous land use methods and ways of production. Farming of jatropha does not threaten food production in Vietnam if the farming plans are implemented as planned. Jatropha may take some land from cassava, but at the same time, food production can be increased if mixed farming is used on some farms. Plenty of new research information and practical experiences on jatropha farming has to be collected before results of the real sustainability of the farming are ready. Carefully considered continuation and documentation of present and future projects would help to understand the possibilities of jatropha diesel in Vietnam and elsewhere.

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麻疯树(Jatropha curcas L.)属大戟科麻疯树属多年生亚乔木,耐干旱、高温和贫瘠等,具很强的抗逆性,在干热河谷等边际土地上生长良好。其种子富含油脂,是制备生物柴油的理想材料,为重要的能源植物之一。油体(oil body)是种子细胞中重要的细胞器, 脂肪酸以三脂酰甘油(triacylglyeerols,TAG)的形式储存其内,是种子萌发和幼苗生长时所需碳骨架和能量的主要来源。种子萌发为生命萌动并构建成自养个体的过程,是高等植物生长发育中的重要事件。 本论文运用高通量的蛋白质组学研究手段,结合电镜技术和生理学分析,对麻疯树种子油体以及种子萌发过程中蛋白质表达、生理学响应和细胞结构变化进行了研究。 从麻疯树种子胚乳中分离油体,再从油体中提取蛋白,经双向凝胶电泳后,得到油体蛋白质组的二维表达谱,这些蛋白质主要分布在等电点5 ~ 10、分子量12 ~ 66 kDa的范围内;图像分析表明,油体蛋白质组至少有141个蛋白点,其中酸性蛋白74个,碱性蛋白67个,表达丰度较高的多为低分子量碱性蛋白。对其中36个重要蛋白点进行LC-MS/MS质谱分析,得到鉴定的蛋白分别为30个基因的表达产物,主要包括油体重要的结构蛋白油质蛋白(oleosin)和caleosin,麻疯树种子毒蛋白curcin,以及新鉴定得到的另一种可能的麻疯树种子毒蛋白,人体过敏反应蛋白橡胶延伸因子(REF)。还有四个与脂肪酸代谢相关的酶,其中3-羟酰-酰基载体蛋白(ACP)脱水/催化酶和醇酰基转移酶与脂肪酸合成有关,而脂氧合酶和磷脂酶D在脂肪酸降解中发挥作用,显示部分脂肪酸代谢相关的酶在油体储存状态就已附着在油体上,为种子萌发时动员油脂做好了准备。 麻疯树种子胚乳发达,在32℃湿润土壤中很快就会萌动,胚轴伸长露出胚根,长出新根,约4天后形成出土子叶幼苗。种子萌发过程中胚乳主要成分含量测定表明,含水量在前24小时迅速上升,至48小时增加缓慢,此后开始较快上升,可分为三个阶段,呈现“S”型的变化;粗脂肪和粗蛋白在前两个阶段变化不大,进入第三阶段后其含量迅速下降,前者先于后者,分别在萌发后72小时和96小时后开始明显减少,说明被大量降解、转化,供萌发生长利用,其中主要组分亚油酸最为明显。细胞超微结构观察发现,排列整齐充满整个胚乳细胞的油体和嵌合在油体中的蛋白储存泡在种子萌发过程中,随着线粒体、乙醛酸循环体和液泡的出现增多或增大而被逐渐解体、减少或消失;同时,发现脂肪酸主要在乙醛酸循环体、蛋白颗粒主要在液泡中被降解或转化。 蛋白质组学分析表明,麻疯树种子在萌发72小时过程中变化量在两倍以上的差异蛋白点共有141个,所有的差异蛋白均通过LC-MS/MS分析和NCBI蛋白数据库搜索得到鉴定。其中包括多个参与降解储藏油脂的酶,如乙醛酸循环途径中的顺乌头酸酶,异柠檬酸裂解酶和苹果酸脱氢酶等,均从种子萌发48小时开始表达量明显上升;葡糖异生途径中的酶在种子萌发中的积累略晚于乙醛酸循环途径,如烯醇酶,磷酸甘油酸变位酶,磷酸甘油酸激酶,磷酸丙糖异构酶和醛缩酶大多在萌发约60小时后表达量开始上调。分析结果表明,乙醛酸循环途径在种子萌发48小时后被激活,与电镜观察胚乳细胞发现油脂在萌发48小时时开始被动员相一致,因而大规模的油脂动员开始于种子萌发的第三阶段。 同时,蛋白质组学的分析结果也得到了种子胚乳组分变化分析及电镜观察结果的印证。超微细胞结构观察显示种子储藏蛋白降解在萌发第二阶段启动,主要在液泡中进行降解。粗脂肪的含量在72小时时显著降低,而电镜观察显示此时胚乳细胞中出现中央大液泡,出现大量的线粒体和乙醛酸循环体,细胞结构发生重大变化,萌发96小时后仅有少量油体残留于胚乳细胞中,这些都为储藏油脂在麻疯树种子萌发过程中的降解方式提供了重要证据。许多其他的功能蛋白在种子萌发过程中也发生了变化,表明种子萌发过程中不仅发生储藏物质的动员,也发生抗逆反应以及植物形态的构建等众多其他生理生化反应。 本研究首次对麻疯树种子油体进行了蛋白组成分析,并结合电镜技术及生理分析深入探讨了种子储藏物质在萌发中的降解方式,为更好的理解油体结构、木本油料种子的萌发机制和对麻疯树进行品种的改良提供了参考。

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Os biocombustíveis têm estado na linha da frente das políticas energéticas mundiais visto que as suas vantagens conseguem colmatar as incertezas e resolver alguns dos problemas associados aos combustíveis fósseis. O biodiesel tem provado ser um combustível muito fiável, alternativo ao petrodiesel. É uma mistura de ésteres alquílicos produzidos a partir de óleos vegetais e gorduras animais através de uma reacção de transesterificação. Como combustível, o biodiesel é economicamente viável, socialmente responsável, tecnicamente compatível e ambientalmente amigável. O principal desafio associado ao seu desenvolvimento tem a ver com a escolha de matéria-prima para a sua produção. Nos países do terceiro mundo, óleos alimentares são mais importantes para alimentar pessoas do que fazer funcionar carros. Esta tese tem como objectivos produzir/processar biodiesel a partir de recursos endógenos de Timor-Leste e medir/prever as propriedades termodinâmicas do biodiesel, a partir das dos esteres alquílicos. A síntese do biodiesel a partir dos óleos de Aleurites moluccana, Jatropha curcas e borras de café foram aqui estudados. As propriedades termodinâmicas como densidade, viscosidade, tensão superficial, volatilidade e velocidade do som também foram medidas e estimadas usando modelos preditivos disponíveis na literatura, incluindo as equações de estado CPA e soft-SAFT. Timor-Leste é um país muito rico em recursos naturais, mas a maioria da população ainda vive na pobreza e na privação de acesso a serviços básicos e condições de vida decentes. A exploração de petróleo e gás no mar de Timor tem sido controlado pelo Fundo Petrolífero. O país ainda carece de electricidade e combustíveis que são cruciais para materializar as políticas de redução da pobreza. Como solução, o governo timorense criou recentemente o Plano Estratégico de Desenvolvimento a 20 anos cujas prioridades incluem trazer o desenvolvimento do petróleo do mar para a costa sul de Timor-Leste e desenvolver as energias renováveis. É neste último contexto que o biodiesel se insere. O seu desenvolvimento no país poderá ser uma solução para o fornecimento de electricidade, a criação de empregos e sobretudo o combate contra a pobreza e a privação. Para ser usado como combustível, no entanto, o biodiesel deve possuir propriedades termodinâmicas coerentes com as especificadas nas normas da ASTM D6751 (nos Estados Unidos) ou EN 14214 (na Europa) para garantir uma adequada ignição, atomização e combustão do biodiesel no motor.

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The biofilms microbial forms of association are responsible for generating, accelerating and / or induce the process of corrosion. The damage generated in the petroleum industry for this type of corrosion is significatives, representing major investment for your control. The aim of this study was to evaluate such tests antibiograms the effects of extracts of Jatropha curcas and essential oil of Lippia gracilis Schauer on microrganisms isolated from water samples and, thereafter, select the most effective natural product for further evaluation of biofilms formed in dynamic system. Extracts of J. curcas were not efficient on the complete inhibition of microbial growth in tests type antibiogram, and essential oil of L. gracilis Schauer most effective and determined for the other tests. A standard concentration of essential oil of 20 μL was chosen and established for the evaluation of the biofilms and the rate of corrosion. The biocide effect was determined by microbial counts of five types of microorganisms: aerobic bacteria, precipitating iron, total anaerobic, sulphate reducers (BRS) and fungi. The rate of corrosion was measured by loss of mass. Molecular identification and scanning electron microscopy (SEM) were performed. The data showed reduction to zero of the most probable number (MPN) of bacteria precipitating iron and BRS from 115 and 113 minutes of contact, respectively. There was also inhibited in fungi, reducing to zero the rate of colony-forming units (CFU) from 74 minutes of exposure. However, for aerobic and anaerobic bacteria there was no significant difference in the time of exposure to the essential oil, remaining constant. The rate of corrosion was also influenced by the presence of oil. The essential oil of L. gracilis was shown to be potentially effective

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Trata-se do primeiro registro de ocorrência de Guyalna cuta (Walker) (Hemiptera: Cicadidae) em pinhão-manso, Jatropha curcas L. (Euphorbiaceae) no Estado de Mato Grosso do Sul. Adultos desse inseto foram observados na parte aérea da planta, durante novembro e dezembro de 2008 e de 2009. em Mato Grosso do Sul, existem plantios comerciais e experimentais do pinhão-manso, tornando-se necessários estudos relacionados a este inseto, a fim de prevenir eventuais danos à cultura.

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Official rules for seed analysis don't establish criteria to execute germination tests for all species. This way, the aim of this research was to determinate the substrate, temperature and counting time for the germination test of physic nut seeds. For the germination test, four replications of 20 seeds were used, evaluating daily the normal seedlings until the end of germination. Initially, the substrates with sowing in vermiculite, were evaluated in rolled paper towels, in sand and in soil using alternating temperature of 20-30 degrees C. The most favorable substrates for germination were evaluated with another stage, using constant temperatures of 25, 30 and 35 degrees C and alternating ones, of 15-35 degrees C, 20-35 degrees C and 20-30 degrees C. One concluded that the germination test of physic nut seeds must be performed with the alternating temperature of 20-30 degrees C in sand or paper towel and with final counting 10 days after sowing.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)