Orientadores: Durval Rodrigues de Paula Junior, Sylvio Luis Honório / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola / Made available in DSpace on 2018-08-23T17:03:06Z (GMT). No. of bitstreams: 1 Aguiar_RosaHelena_D.pdf: 2411611 bytes, checksum: cc0a7bb404d742457c915d8126132bf5 (MD5) Previous issue date: 2013 / Resumo: O saneamento além de ser importante para a preservação dos recursos naturais representa uma ação preventiva eficaz para a melhoria do bem estar e da qualidade de vida da população nas questões relacionadas à saúde pública. A prática do uso de água residuária tem grandes vantagens, sobremaneira no aporte de nutrientes às plantas, fator que contribui para um crescimento mais rápido. Nesta pesquisa optou-se por utilizar o girassol (Helianthus annuus L.) ornamental que foi irrigado com águas residuárias. Objetivou-se a viabilidade do uso da área com disposição de esgoto tratado em reatores anaeróbios, por meio da avaliação do seu desenvolvimento e da sua produtividade durante três diferentes épocas de semeadura, visando reduzir os custos com nutrientes. Realizou-se esse experimento na área experimental da Faculdade de Engenharia Agrícola FEAGRI/UNICAMP, e foram avaliados cinco diferentes experimentos, dois deles por meio de reuso de efluentes de reatores - Upflow Anaerobic Sludge Blanket (UASB) e Reator Anaeróbio Compartimentado (RAC) associado a filtros anaeróbios, enquanto que os outros foram constituídos de: Testemunha, sem qualquer tipo de irrigação; com irrigação, utilizando somente água tratada, e com água tratada em área fertilizada com NPK. Foram avaliados respostas fitomorfológicas da cultura, assim como: diâmetro dos caules (DC); altura das plantas (HP); diâmetro dos capítulos (DCp); massa seca dos caules e das folhas (MS); número de folhas (NF) e sua produtividade. Os sistemas modulares (UASB e RAC) de tratamento de esgoto apresentaram um bom desempenho, com elevados valores de remoção de SSed (98,72; 98,36%), e DQO (72,37; 75,79%) não havendo diferença significativa entre os sistemas de tratamento. Constatou-se também que os canteiros com tratamentos com reuso de efluentes promoveram alteração na fertilidade do solo, com o aumento nos valores de saturação por bases (V%) na profundidade de 0 - 20 cm. Analisando os efeitos sobre a cultura nos três plantios, verificou-se um melhor desenvolvimento nos canteiros com os tratamentos do efluente, quando comparado com os demais tratamentos principalmente no segundo e terceiro plantio. Sistemas modulares de tratamento de esgotos associados ao reuso agrícola de seus efluentes podem agregar valores à produção agrícola, podendo ser utilizado inclusive no período de chuvas e em locais onde há escassez de água pluvial / Abstract: Sanitation is also important for the preservation of natural resources, represents an effective preventive action to improve the well-being and quality of life of the population on issues related to public health. The practice of using wastewater has great advantages, particularly in the supply of nutrients to plants, factor that contributes to a faster growth. In this research we decided to use the Sunflower (Helianthus annuus L.) ornamental that was irrigated with wastewater. The viability of the use of the area with provision of treated sewage in anaerobic reactors, by assessing their development and their productivity during three different periods of sowing to reduce costs with nutrients. This research was developed in the experimental area of the Faculty of agricultural engineering FEAGRI/UNICAMP, and evaluated five different treatments, two of them by means of Upflow Anaerobic Sludge Blanket reactors (UASB) and Anaerobic Reactor Chambered (ARC) associated with anaerobic filters, while the others were made up of: witness, without any kind of irrigation; with irrigation, using only treated water and treated water in the area fertilized with NPK. Fitomorfológicas culture responses were evaluated as: diameter of stems (DS); plant height (HP); diameter of the chapters (DCp); dry mass of stems and leaves (DM); number of leaves (NF) and your productivity. Modular systems (UASB and ARC) sewage treatment showed a good performance, with high values of removing SSed (98.72; 98.36), and COD (72.37; 75.79) with no significant difference between the treatment systems. It was noted also that the flower beds with wastewater reuse treatments promoted change in the fertility of the soil, with the increase in base saturation values (V%) at the depth of 0-20 cm. Analyzing the effects on culture in three plantations, there was a better development in the flower beds with the effluent treatments, when compared with the other treatments mainly in the second and third planting. Modular wastewater treatment system associated with the agricultural reuse of wastewater can add value to their agricultural production, and can be used throughout the year even in places where there is scarcity of rainwater / Doutorado / Agua e Solo / Doutor em Engenharia Agrícola

L'extraction aqueuse des lipides de la graine de tournesol est étudiée en contacteur agité. La diffusion à l'intérieur des particules est le facteur limitant de l'échange de matière. Les protéines sont impliquées dans l'entraînement et la stabilisation des lipides par l'eau. Le fractionnement de la plante entière est également étudié avec l'eau en extrusion bi-vis. Un extrait et un raffinat sont obtenus séparément et en une seule étape continue. Des rendements d'extraction en huile de 55 % peuvent être obtenus sous forme d'émulsions huile/eau. Leur stabilité est assurée par la présence à l'interface de tensioactifs : les phospholipides et les protéines voire les pectines. Les extraits se composent aussi d'une phase hydrophile. Prépondérante, elle contient des composés hydrosolubles (protéines, pectines…). Riches en fibres, les raffinats présentent une teneur significative en protéines au comportement thermoplastique. Ils peuvent être transformés en agromatériaux par thermomoulage.

The renewed interest in energy for biomass is supported by the need for different energy sources and the need to protect the environment. Recently, because of increases in crude oil prices, limited resources of fossil oil and environmental concerns there has been renewed focus on vegetable oils and animal fats to make a biodiesel fuel. What is known as biodiesel (methyl or ethyl esters) is a vegetable oil or animal fat chemically treated to replace traditional diesel fuel. Performance parameters and exhaust emissions of a diesel engine fuelled with sunflower and beef tallow ethyl esters and a blend of ethyl and methyl esters, subjected to pre-heating at two temperatures ranges, namely T55 (50 to 60ºC) and T75 (70 to 80ºC), in order to lower its viscosities, have been investigated. Tests were carried out at full load conditions in a four cylinders, four-stroke indirect injection diesel engine. Engine tests, short-term, were conducted at a range speed from 1900 to 4400 rpm. The injection timing was retarded from the manufacturer s recommended setting. The tests were carried out using the same engine and test procedures so that comparative assessments may be made. The tests data were used for evaluating the brake power, exhaust gas temperatures, specific fuel consumption and gaseous emissions. The analysis of the results determined that the level of pre-heating have influence on the performance for used esters. The tests performed at T55 showed the best values of torque (N.m), power (kW) and specific fuel consumption (g.kW-1.h-1) that the tests performed at T75. The bests experiments results were obtained with sunflower ethyl ester and the blend containing 50,0% sunflower ethyl ester and 50,0% beef tallow methyl ester, at -2º BTDC and T55 temperature range. The findings showed that, by using biodiesel, harmful emissions (CO, HC and NOx) can be reduced to some extent of B2 by adjusting the injection pump timing properly and pre-heating of fuel. / O renovado interesse por energia da biomassa é apoiado na necessidade de fontes alternativas de energia e de proteção ambiental. Recentemente, devido ao aumento dos preços do óleo cru, a limitação de seus recursos e as questões relacionadas ao ambiente, um renovado foco passou a existir sobre os óleos vegetais e gorduras animais para produção de um biodiesel combustível. O que é conhecido como biodiesel (éster metílico ou etílico) é um óleo vegetal ou gordura animal tratado quimicamente para substituir o combustível diesel tradicional. Parâmetros de desempenho e emissões de exaustão foram investigados para um motor diesel alimentado com ésteres etílicos de óleo de girassol e de sebo bovino e por uma mistura composta pelo éster etílico de óleo de girassol e pelo metílico de sebo bovino numa proporção volumétrica igual (50,0%+50,0%). Os ésteres estavam sujeitos ao pré-aquecimento segundo duas faixas de temperaturas, chamadas de T55 (50 a 60ºC) e T75 (70 a 80ºC), como forma de redução da viscosidade. Os testes foram conduzidos sob condição de carga máxima em um motor diesel de quatro cilindros, quatro tempos e de injeção indireta de combustível. Os ensaios de curta duração foram efetuados em uma faixa de rotações compreendida entre 1900 e 4400 rpm. O ponto de avanço de injeção foi atrasado em relação ao ponto original recomendado pelo fabricante. Os testes foram conduzidos utilizando o mesmo motor e os mesmos procedimentos de testes para permitir a comparação dos valores obtidos. Nos ensaios foram obtidos os valores de potência, torque, consumo específico de combustível e gases de exaustão. A análise dos resultados indica que o nível de pré-aquecimento tem influência sobre o desempenho dos ésteres utilizados. Os ensaios conduzidos à T55 mostraram melhores valores para torque (N.m), potência (kW) e consumo específico de combustível (g.kW-1.h-1) que os testes executados à T75. Os melhores resultados do experimento foram obtidos pelo éster etílico de girassol e pela mistura contendo 50,0% de éster etílico de girassol e 50% de éster metílico de sebo bovino, sob 2º (P2) de atraso no ponto de injeção e aquecidos na faixa de temperaturas de T55. Os resultados indicam que, pelo uso do biodiesel, as emissões prejudiciais (CO, HC e NOx) podem ser reduzidas aos mesmos níveis do B2 através do ajuste apropriado do ponto de avanço da injeção e o pré-aquecimento do combustível.

Le phoma (Phoma macdonaldii / Leptosphaeria linquistii) et le phomopsis (Phomopsis / Diaporthe helianthi) sont deux champignons pathogènes majeurs du tournesol. Dans un contexte d’objectif de réduction de la lutte chimique, une meilleure compréhension des interactions peuplement-agents pathogènes-environnement-conduite de culture est nécessaire. Des essais menés au champ et en serre à Auzeville en 2010 et 2011 ont permis de décomposer les effets de la conduite de culture du tournesol sur l’apparition et le développement des deux maladies. Les variables clés de l’architecture des plantes en peuplement et du microclimat, modifiées par la conduite de culture (choix variétal, densité de semis, fertilisation azoté, irrigation) ont été décrites et mises en relation avec les composantes de la maladie. Ainsi, pour le phomopsis, le rôle déterminant du microclimat résultant du niveau de développement de la couverture foliaire lors des phases initiales d’infection a été confirmé. La taille des feuilles et le diamètre des tiges sont des caractères déterminants de la progression des dégâts sur feuille et tige. Les conséquences des attaques de phomopsis sur feuille en termes de mécanismes de nuisibilité ont été analysées finement et modélisées. Pour le phoma, le rôle du statut nutritionnel azoté dans la progression des attaques sur tige et collet a été confirmé. La fonction régulatrice du phoma vis-à-vis des attaques de phomopsis sur feuille a été quantifiée. Sur le plan de la modélisation, plusieurs approches ont été menées : (i) Evaluation de la qualité prédictive d’Asphodel, modèle épidémiologique prévoyant les émissions de ascospores de Phomopsis ; application à différentes conduites de culture et extension au phoma pour la partie inoculum primaire ; (ii) développement d’un modèle prédictif de l’incidence du phoma prenant en compte les effets climatiques, microclimatiques et agronomiques ; (iii) proposition d’une modélisation conceptuelle des interactions plante-agent(s) pathogène(s)-environnement-conduite de culture. Ce travail pourra, à terme, contribuer à la conception de stratégies de gestion des principales maladies du tournesol, à l’échelle de la parcelle ou du territoire. / Phoma (Phoma macdonaldii / Leptosphaeria linquistii) and phomopsis (Phomopsis / Diaporthe helianthi) are two major sunflower fungal diseases. In a context of reduction of pesticides, a better understanding of the interactions between crop canopy, pathogens, environment and cropping practices is needed. Field and greenhouse experiments set up at Auzeville in 2010 and 2011 allowed to dissect the impact of sunflower crop management on disease appearance and development. Key variables of plant architecture and microclimate, modified by cropping practices (variety choice, sowing density, nitrogen fertilization, irrigation) were described and related to disease components. Thereby, for phomopsis, the key role of microclimate resulting from the level of development of leaf area during the initial stages of infection was confirmed. Leaf length and stem diameter are key characters for necrosis progression on leaf and stem. The impact of phomopsis leaf infection in term of damage mechanism was analysed and modelled. For phoma, the effect of nitrogen nutrition status on necrosis progression on stem and stem base was confirmed. The regulatory function of phoma towards phomopsis leaf infection was quantified. In terms of modelling, several approaches were developed: (i) evaluation of the predictive quality of Asphodel, an epidemiological model predicting Phomopsis ascospore release; application to different cropping practices and extension to phoma for primary inoculum; (ii) development of a predictive model for phoma incidence taking into account the climatic, microclimatic and agronomic effects; (iii) proposal of a conceptual model of the interactions between crop canopy, pathogens, environment and cropping practices. This study could contribute to the design of integrated management strategies for the main sunflower diseases, at field or at territory scale.

Made available in DSpace on 2016-05-02T13:55:17Z (GMT). No. of bitstreams: 1 Luiz Silva Souza-dissertacao.pdf: 3490471 bytes, checksum: c67d9a32f1552af2738fbcd53645873e (MD5) Previous issue date: 2012-07-10 / In addition to being an important source of nutrients, the potential therapeutic effectiveness of H. annuus L. seeds has been previously demonstrated; the beneficial properties of H. annuus L. seeds include an ability to relieve asthmatic symptoms, protective effects on the stomach, benefits to healing, and anti-inflammatory and anti-microbial properties. This research evaluated the mutagenicity and anti-mutagenicity of oil and tincture of H. annuus L. seeds using the micronucleus assay in bone marrow of mice. The interaction between these preparations and the genotoxic effects of doxorubicin (DOX) was also analyzed. Experimental groups were evaluated after 24-48 h of treatment with N-Nitroso-N-ethylurea (NEU) and DOX (positive controls), NaCl (a negative control), a sunflower tincture (250-2,000 mg.Kg-1 of THALS) and two sources of sunflower oils (250-2,000 mg.Kg-1 of POHALS and FOHALS). Anti-mutagenic assays were carried out using the sunflower tincture and oils separately and in combination with these controls. The frequency of micronucleated polychromatic erythrocytes (MNPCEs) was significantly different (p &#61500; 0.05) between (i) the positive and negative control treatments, (ii) the positive controls and animals treated with THALS and (iii) animals treated with THALS and and THALS combined with the positive controls. However, a slight genotoxicity was observed in the animals treated with the combination of THALS+DOX. Both sources of oils (FOHALS and POHALS) revealed similar results; in these groups, the frequencies of MNPCEs were similar to those observed in negative controls. Statistically significant differences were also observed between the sunflower oil treatments and their associated positive controls. There was no genotoxicity (clastogenicity/aneugenicity) observed in THALS, POHALS and FOHALS regardless of the dose, time (except FOHALS) and gender of mouse (except POHALS and FOHALS). The moderate anti-genotoxic effects of THALS suggest a potential slight protective mechanism against DOX-induced genotoxic effects. / A efetividade terapêutica potencial das sementes de H. annuus L. tem sido demonstrada (alívio dos sintomas da asma, efeitos da proteção gástrica, cicatrização, propriedades anti-inflamatórias e antimicrobianas), em adição à sua importante fonte de nutrientes. Esta pesquisa avaliou a mutagenicidade e anti-mutagenicidade do óleo e da tintura de sementes de H. annuus L. usando o ensaio do micronúcleo em medula óssea de camundongos. A associação sobre os efeitos genotóxicos induzidos pela doxorrubicina (DOX) também foi analisada. Grupos experimentais foram avaliados após 24-48h de tratamento com N-Nitroso-N-ethylurea (NUE) e DOX (controles positivos), NaCl (controle negativo), tintura (250-2.000 mg.Kg-1 de THALS) e duas fontes de óleo de girassol (250-2.000 mg.Kg-1 de POHALS e FOHALS). Ensaios anti-mutagênicos foram realizados usando os controles positives associados com a tintura e óleos de girassol, separadamente. A frequência de eritrócitos policromáticos micronucleados (MNPCEs) foi estatisticamente diferente (p < 0,05) entre (i) os tratamentos controles positives e negativo, (ii) controles positivos e tratamento com THALS e (iii) tratamento com THALS e sua associação aos controles positivos. Contudo, uma leve genotoxicidade foi observada na associação THALS+DOX. Ambas as fontes de óleos (FOHALS e POHALS) revelaram resultados similares, cujas frequências de MNPCEs foram consistentes com aqueles observados no controle negativo. Diferenças significativas também ocorreram entre os tratamentos de óleos e suas associações com os controles positivos. A ausência de genotoxicidade (clastogenia/aneugenia) da THALS, POHALS e FOHALS pode ser inferida independentemente da dose, tempo (exceto para FOHALS) e gênero de camundongo (exceto para POHALS e FOHALS). Efeitos anti-genotóxicos moderados de THALS sugerem um potencial mecanismo ligeiramente protetor sobre os efeitos genotóxicos induzidos pela DOX.

Orientador: Rogério Pinto Mota / Resumo: Esta tese teve como o intuito o estudo e caracterização de jatos de plasma com diferentes diâmetros no tratamento do polímero Politereftalato de Etileno (PET), visando estudar a uniformidade e a área de alcance dos tratamentos. Posteriormente, um desses jatos foi utilizado para o tratamento de sementes de girassol, com o objetivo de investigar as modificações superficiais, físico-químicas e o comportamento biológico das sementes após os tratamentos a plasma, buscando compreender os mecanismos de interação do plasma com as sementes. A caracterização superficial do PET foi realizada através de medições de ângulo de contato, rugosidade e análise das mudanças químicas com a Espectroscopia de Fotoelétrons Excitados por Raios X (XPS). Enquanto que, as caracterizações realizadas nas sementes foram medidas de ângulo de contato, absorção de água e corante, perda de massa, Espectroscopia no Infravermelho com Transformada de Fourier por Refletância Total Atenuada (FTIR-ATR) e Microscopia Eletrônica de Varredura (MEV). Para avaliação da parte biológica foram realizados ensaios de taxa de germinação e de taxa de crescimento. Os tratamentos no PET com os três jatos de plasma utilizados demonstraram uma diminuição considerável nos valores de ângulo de contato e a área de tratamento alcançada por cada jato foi devidamente calculada. Através do aumento dos valores da rugosidade foi possível verificar que o tratamento a plasma estendeu-se para fora do cone do jato. Houve também incorporação de... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The purpose of this thesis was to study and characterize plasma jets with different diameters in the treatment of polyethylene terephthalate (PET) in order to study the treatment range and uniformity. Subsequently, one of these jets was used for the treatment of sunflower seeds, with the objective to investigate the seeds surface, physicochemical changes and the biological behavior of the seeds after the plasma treatments, seeking to understand the mechanisms of the interaction of the plasma with the seeds. The superficial characterization of the PET was performed through measurements of water contact angle, roughness and analysis of chemical changes with X-ray Photoelectron Spectroscopy (XPS). While, the characterizations performed on sunflower seeds were water contact angle, water and dye absorption, mass loss, Fourier Transform Infrared Spectroscopy by Total Attenuated Reflectance (FTIR-ATR) and Scanning Electronic Microscopy (SEM). For the biological evaluation germination rate and growth rate tests were performed. The treatments on PET with the three plasma jets showed a considerable decrease in water contact angle values and the treatment area obtained by each jet was calculated. By increased roughness values it was possible to verify that the plasma treatment extended outside the cone of the jet. There was also incorporation of functional groups of O, increase of small amounts of N and removal of contaminants in the plasma treated PET samples confirmed by the XPS analy... (Complete abstract click electronic access below) / Doutor

In dieser Arbeit wird die Eignung eines Haarwurzelsystems (HR) aus transgenen Sonnenblumen-hairy roots zur biotechnologischen Produktion von α-Tocopherol untersucht. Es wurden hairy roots mit und ohne Transgene erzeugt. Transgene HR exprimieren Tocopherolbiosynthesegene aus Arabidopsis thaliana. Die HR wurden unterschiedlichen Stressoren unterworfen, um die α-Tocopherolproduktion binnen eines Zeitraums zu überprüfen. Stressoren waren verringerte Kohlenstoffquelle, Beleuchtung und der Zusatz von Zytokininen. Die Produktionsleistung des Systems ist schlussendlich ungenügend zur kostengünstigen Produktion von α-Tocopherol.

M. Tech. (Department of Chemical Engineering, Faculty of Engineering and Technology), Vaal University of Technology. / The industrialisation of the twenty-first century and the worldwide population growth led to the high demand for energy. Fossil fuels are the leading contributor to the global energy, and subsequently, there is a high demand of fuels. The decrease of global fossil fuels and the environmental air pollution caused by these fuels are concerning. Therefore, eco-friendly and renewable fuel such as biodiesel is one the leading alternative. Chromatography and Spectroscopy are the most used analytical methods and proven reliable but are time-consuming, requires qualified personal, extensive samples preparation, costly and do not provide in-situ real-time monitoring. Fourier Transform Infrared (FTIR) has mainly been used for qualitative analysis of biodiesel, but not much work has been reported in real-time monitoring. This study focused on the modelling of in-situ real-time monitoring of the biodiesel production from sunflower oil using FTIR (Fourier Transform Infrared). The first part of the study investigated the effect of catalyst ratio and methanol to oil ratio on biodiesel production by using central composite design (CCD). Biodiesel was produced by transesterification using Sodium Hydroxide as a homogeneous catalyst. A laboratory-scale reactor consisting of; flat bottom flask mounted with a reflux condenser, a hot plate as heating element equipped with temperature, timer and stirring rate regulator was used. Key parameters including, time, temperature and mixing rate, were kept constant at 60 minutes, 60 oC and 600 RPM, respectively. From the results obtained, it was observed that the biodiesel yield depends on catalyst ratio and methanol to oil ratio. The highest yield of 50.65 % was obtained at a catalyst ratio of 0.5 wt% and methanol to oil mole ratio 10.5. The analysis of variances of biodiesel yield showed the R2 value of 0.8387. A quadratic mathematical model was developed to predict the biodiesel yield in the specified parameters range. The same set-up was used to produce waste margarine biodiesel using a homogeneous catalyst, potassium hydroxide (KOH). The effects of four reaction parameters were studied, these were: methanol to oil ratio (3:1 to 15:1), catalyst ratio (0.3 to 1.5 wt. %), temperature (30 to 70 oC), time (20 to 80 minutes). The highest yield of 91.13 % was obtained at 60°C reaction temperature, 9:1 methanol to oil molar ratio, 0.9 wt. % catalyst ratio and 60 minutes. The important biodiesel fuel properties were found to be within specifications of the American Standard Test Method specifications (ASTM). It was concluded that waste margarine can be used to produce biodiesel as a low-cost feedstock. The core of the study was performed using EasyMax Mettler Toledo reactor equipped with a DiComp (Diamond) probe. The quantitative monitoring of the biodiesel production was performed by building a quantitative model with multivariate calibration using iC Quant module from iC IR 7.0 software. Fourteen samples of known concentrations were used for the modelling which were taken in duplicate for model calibration and cross-validation, data were pre-processed using mean centring and variance scale, spectrum math square root and solvent subtraction. These pre-processing methods improved the performance indexes from 7.98 to 0.0096, 11.2 to 3.41, 6.32 to 2.72, 0.9416 to 0.9999, RMSEC, RMSECV, RMSEP and R2Cum, respectively. The R2 values of 1 (training), 0.9918 (test), 0.9946 (cross-validation) indicated the fitness of the model built. The model was tested against the univariate model; small discrepancies were observed at low concentration due to unmodelled intermediates but were quite close at concentrations above 18%. The software eliminated the complexity of the Partial Least Square (PLS) chemometrics. It was concluded that the model obtained could be used to monitor transesterification of sunflower oil at industrial and lab scale. The model thus obtained, a batch reactor setup, EasyMax Mettler Toledodo reactor was used, the experiments were designed and monitored using iControl software. The results were recorded and quantified using iC IR software based on the biodiesel calibrated monitoring model built. The optimisation of the biodiesel was performed using three key parameters (methanol to oil ratio, catalyst ratio and temperature) while keeping time at 60 minutes and mixing rate at 150RPM. The highest yield of 97.85 % was obtained at 60 oC, 0.85 wt % catalyst ratio and 10.5 methanol to oil mole ratio. The analysis of variances of biodiesel production showed the values of 0.9847, 0.9674 and 0.8749, for R-squared, adjusted R-squared and predicted R-squared, respectively. A quadratic mathematical model was developed to predict the biodiesel conversion in the specified parameters ranges. Using the Arrhenius equation, activation energy (Ea) and frequency factor were found to be 41.279 kJ.mole-1 and 1.08 x10-4 M-1. s-1, respectively. The proposed kinetics model was a pseudo-first-order reaction. It was concluded that the model obtained can be used for industrial and laboratory-scale biodiesel production monitoring.

Les protéines extraites des végétaux sont des matériaux relativement peu coûteux, non toxiques, biocompatibles et biodégradables. Elles représentent une bonne alternative aux protéines d’origine animale et aux polymères dérivés du pétrole. Dans le cadre de cette étude, les protéines extraites de graines de soja et de tournesol ont été utilisées en tant que matériaux enrobants pour la microencapsulation de la matière active hydrophobe (α-tocophérol) ou hydrophile (acide ascorbique) par le procédé d’atomisation. Les protéines de soja sont largement utilisées dans les applications alimentaires et non-alimentaires, notamment en microencapsulation. Elles sont donc étudiées dans ce travail comme matériau enrobant de référence. Les protéines de tournesol n’ont quant à elles pas d’application industrielle concrète, si ce n’est sous la forme de tourteaux dans l’alimentation animale. C’est pourquoi il nous semble pertinent de trouver des nouvelles voies de valorisation pour ce coproduit d’origine agricole. Plusieurs modifications des protéines, telles que l’hydrolyse enzymatique, l’acylation, la réticulation enzymatique et la cationisation ont été étudiées dans le but d’améliorer les propriétés encapsulantes du matériau enrobant. Dans le contexte de la chimie verte, toutes les modifications ont été effectuées sans utilisation de solvants organiques ni de catalyseurs chimiques. L’influence des modifications chimiques et enzymatiques des protéines, et des paramètres du procédé (pression d’homogénéisation, ratio matériau enrobant/matière active et concentration en protéines) sur les différentes caractéristiques des préparations liquides et des microparticules (viscosité, taille des gouttelettes dans le cas des émulsions, morphologie et taille des microparticules), ainsi que sur les paramètres liés au procédé d’atomisation (rendement et efficacité de microencapsulation) a été particulièrement étudiée au cours de ce travail. Les résultats obtenus confirment que l’extrait protéique de tournesol est tout à fait pertinent comme matériau enrobant et permet d’obtenir des efficacités de microencapsulation significativement plus élevées par rapport à celles obtenues avec l’extrait protéique de soja. / Proteins extracted from vegetables are relatively low-cost, non-toxic, biocompatible and biodegradable raw materials. They represent a good alternative to animal-based proteins and petroleum-extracted polymers. In this study, proteins derived from soybean and sunflower seeds were used as wall materials for microencapsulation of hydrophobic (-tocopherol) or hydrophilic (ascorbic acid) active material by spray-drying technique. Soybean proteins are widely used in food and non-food applications, especially in microencapsulation. They were studied in this work as wall material of reference. Sunflower proteins are not actually used in industrial application, but only in the form of oil-cake for animal feeding. That’s why new ways of valorization of this agricultural by-product should be investigated. Several proteins’ modifications such as enzymatic hydrolysis, acylation, cross-linking and cationization were studied in order to improve encapsulating properties of wall material. In the context of green chemistry, all the modifications and preparations were performed without use of organic solvents and chemical catalysts. The effect of protein chemical and enzymatic modifications, and process parameters (homogenization pressure, wall/core ratio and protein concentration) on different characteristics of liquid preparations and microparticles (viscosity, emulsion droplet size, microparticle size and morphology) and on parameters related to the spray-drying process (yield and efficiency of microencapsulation) was particularly investigated in this study. The obtained results confirmed that sunflower proteins are quite suitable as encapsulating agent and provide the microencapsulation efficiencies significantly higher compared to those obtained with soy proteins.

Orientador: João Batista Kochenborger Fernandes / Banca: Elisabeth Criscuolo Urbinati / Banca: Maria Cristina Thomaz / Banca: Teresa Cristina Ribeiro Dias Koberstein / Banca: Antônio Cleber da Silva Camargo / Resumo: O objetivo deste estudo foi avaliar o efeito da utilização de dietas contendo diferentes ingredientes fibrosos (farelo de soja, casca de soja, farelo de girassol e polpa cítrica, este ultimo avaliado em dois níveis de inclusão) sobre o tempo de trânsito gastrointestinal, as digestibilidades da proteína e da energia, o desempenho, a composição corporal, os parâmetros bioquímicos, os índices organométricos e a morfometria intestinal de juvenis de pacu (Piaractus mesopotamicus). Os peixes alimentados com as dietas contendo farelo de soja e farelos de girassol tiveram os melhores resultados de digestibilidade e desempenho, sem apresentar alterações fisiológicas e metabólicas. A inclusão casca de soja na dieta atrasou o tempo de trânsito gastrointestinal, piorou a digestibilidade da proteína e da energia, prejudicou o desempenho, diminuiu as proteínas totais sangüíneas e aumentou a porcentagem de lipídeo muscular. A dieta contendo 45% polpa cítrica acelerou o tempo de trânsito gastrointestinal, piorou o desempenho, provocou alterações na composição corporal e na morfometria intestinal. Cada ingrediente fibroso, em função de sua composição de fibras alimentares e carboidratos complexos, altera o funcionamento do sistema digestório e o aproveitamento de nutrientes, com conseqüências sobre a fisiologia, o metabolismo e o desempenho dos juvenis de pacu / Abstract: This study aim was to evaluate the effects of diets containing different fiber sources (soybean meal, soybean hulls, sunflower meal and citrus pulp, this last evaluated at two inclusion levels) on gastrointestinal transit time, protein and energy digestibility of protein, performance, body composition, biochemical parameters, organometric index and intestinal morphology of juvenile pacu (Piaractus mesopotamicus). Fish fed diets containing soybean meal and sunflower meal had best digestibility and performance results, with no physiological and metabolic diseases. The inclusion of soybean hulls in the diet delayed gastrointestinal transit time, decreased the digestibility of protein and energy, worsened performance, reduced total blood proteins and increased the percentage of muscle lipid. Diet containing 45% citrus pulp accelerated gastrointestinal transit time, worsened performance, led to changes in body composition and affects the intestinal morphology. Each fibrous ingredient, depending on dietary fiber and complex carbohydrates composition, differently affects the digestive system functioning and nutrient use, with consequences on physiology, metabolism and performance of juvenile pacu / Doutor