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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.
1

Dramatická výchova a práce s dětmi se zrakovým postižením / Drama In Education and education of children with impared seeing

Kyselovičová, Hana January 2013 (has links)
Keywords Drama in education, Visual impairment, Multiple impairment, Mental disability, Method, Technique, Lesson, Methodological material, Integration Abstract The thesis deals with the possibilities of using methods and techniques of Drama in Education with visually impaired children and examines the possibilities of such work with children with a combination of visual impairments and mental disability. The theoretical part is focused on the classification and characterization of visual impairment and its impact on mental and physical development of preschool aged children. It also describes the basic principles of Drama in Education, Drama in Education as an educational field, as it is integrated into framework educational programme for special elementary school and specifies the conditions under which is possible to work with visually impaired children using methods and techniques of Drama in Education, which are also individually analysed. Practical part contains ten lessons of Drama in Education with notes that reflect their progress. For the purpose of thesis the lessons were realized in a group of children with visual and multiple impairments, which is also in thesis described.
2

Micropropagation "in vitro" et effets des polyamines sur la microtubérisation de l'igname du complexe "Dioscorea cayenensis - D. rotundata"

Ondo Ovono, Paul 22 October 2009 (has links)
Les Dioscorea cultivées, dont la reproduction sexuée est aléatoire, sont multipliées essentiellement par voie végétative, ce qui entraîne la dissémination dagents pathogènes dans les plantations, provoquant une baisse de rendement et de qualité des récoltes. Dans ces conditions, les besoins en semences sont rarement comblés et les possibilités dextension de la culture restent limitées. En effet, devant une demande quantitative toujours croissante et qualitative de plus en plus restrictive, les techniques classiques encore employées aussi bien pour la multiplication que pour lamélioration de la production des végétaux sont relativement lentes. En revanche, les opportunités offertes par les cultures de tissus peuvent remédier efficacement aux insuffisances et offrir des améliorations irréalisables par les autres méthodes. La multiplication en alternance par bourgeonnement axillaire à partir de nuds pendant 28 semaines et par mise en germination des microtubercules découpés pendant 16 semaines peut remédier à cette situation. Plusieurs facteurs peuvent avoir un impact sur lefficacité de cette approche: la présence ou labsence de régulateurs de croissance, la teneur en saccharose ou en éléments minéraux du milieu de culture. Dans le cadre de cette étude, les tests réalisés ont montré une formation plus précoce du tubercule en présence de polyamines et dacide jasmonique. Si les teneurs en polyamines endogènes et leur métabolisme sont significativement affectés par les polyamines exogènes, les modifications des teneurs en polyamines endogènes, quant à elles, ne peuvent être directement corrélées avec la formation du tubercule. Un retard dans la formation des tubercules lors dune réduction de la teneur en sucre du milieu de culture a aussi été constaté. Ce retard dans nest pas lié à une réduction de losmolarité du milieu de culture, comme nous avons pu le montrer en remplaçant partiellement le saccharose par du sorbitol. La putrescine et ses précurseurs larginine et lornithine favorisent aussi le développement des tubercules, ceux- ci sont plus longs et plus lourds lorsque ces composés sont ajoutés au milieu de culture à faible concentration. Une augmentation de la teneur endogène en putrescine et en auxine a été observée dans ces conditions. Laddition dacide jasmonique a un effet similaire. Une réduction du développement des tubercules est, par contre, observée en présence dune teneur en saccharose réduite. La réduction de la teneur en sucre dans le milieu de tubérisation a aussi un effet négatif sur la germination ultérieure des microtubercules. Pour pouvoir utiliser les microtubercules comme semences, il faut être assuré dun taux de germination élevé et dun stockage possible. Les microtubercules récoltés après 9 mois de culture et transférés sur un nouveau milieu sans régulateur de croissance germent très rapidement. Aucune dormance nest observée. Les microtubercules peuvent aussi être stockés pendant au moins 18 semaines. Les meilleures conditions pour une germination élevée sont une conservation à lobscurité, sous ± 50% dhumidité relative et à 25°C. Une période de dormance secondaire sinstalle une fois le stockage en cours qui varie entre 20 et 28 semaines respectivement pour les microtubercules les plus rapides et les plus lents. Seuls les tubercules de taille supérieure à 350 mm devront être utilisés pour la germination in vitro ou ex vitro.
3

Bumpy light curves of interacting supernovae

Nyholm, Anders January 2017 (has links)
A supernova (SN) is the explosive destruction of a star. Via a luminous outpouring of radiation, the SN can rival the brightness of its SN host galaxy for months or years. In the past decade, astronomical surveys regularly observing the sky to deep limiting magnitudes have revealed that core collapse SNe (the demises of massive stars) are sometimes preceded by eruptive episodes by the progenitor stars during the years before the eventual SN explosion. Such SNe tend to show strong signatures of interaction between the SN ejecta and the circumstellar medium (CSM) deposited by the star before the SN explosion, likely by mass-loss episodes like the ones we have started to observe regularly. The complex CSM resolved around certain giant stars in our own galaxy and the eruptions of giant stars like η Car in the 19th century can be seen in this context. As the SN ejecta of an interacting SN sweep up the CSM of the progenitor, radiation from this process offers observers opportunity to scan the late mass loss history of the progenitor. In this thesis, interacting SNe and eruptive mass loss of their progenitors is discussed. The SN iPTF13z (discovered by the intermediate Palomar Transient Factory, iPTF) is presented. This transient was followed with optical photometry and spectroscopy during 1000 days and displayed a light curve with several conspicuous re-brigthenings ("bumps"), likely arising from SN ejecta interacting with denser regions in the CSM. Around 200 days before discovery, in archival data we found a clear precursor outburst lasting >~ 50 days. A well-observed (but not necessarily well understood) event like SN 2009ip, which showed both precursor outbursts and a light curve bump, makes an interesting comparison object. The embedding of the (possible) SN in a CSM makes it hard to tell if a destructive SN explosion actually happened. In this respect, iPTF13z is compared to e.g. SN 2009ip but also to long-lived interacting SNe like SN 1988Z. Some suggestions for future investigations are offered, to tie light curve bumps to precursor events and to clarify the question of core collapse in the ambiguous cases of some interacting SNe.
4

Encapsulação de extratos vegetais em leito fluidizado / Encapsulation of herbal extract in fluidized bed

Benelli, Lucimara 19 February 2016 (has links)
Este trabalho objetivou investigar o processo de revestimento/aglomeração de extratos vegetais em leito fluidizado com atomização top spray, visando melhorar a estabilidade dos compostos bioativos dos extratos e suas propriedades farmacotécnicas. Açúcar cristal, pellets de açúcar e de celulose microcristalina, grânulos de celulose microcristalina, grânulos de arroz e farinha de mandioca foram utilizados como partículas sementes. Inicialmente, avaliou-se a influência do tamanho das partículas e diferentes composições de alimentação contendo extrato vegetal de Rosmarinus officinalis (alecrim). Farinha de mandioca e pellets de açúcar de diferentes granulometrias foram empregados como partículas semente. O desempenho do processo foi avaliado através da eficiência de revestimento e porcentagem de aglomeração. Os grânulos formados foram caracterizados quanto ao tamanho, fluidez e retenção de compostos bioativos (polifenóis). As formulações estudadas também foram submetidas à secagem em spray dryer para comparação entre os produtos obtidos. Os resultados obtidos mostraram que a eficiência de revestimento/aglomeração e a porcentagem de aglomeração dependem das propriedades físico-químicas das partículas sementes e das composições alimentadas. As viscosidades das formulações contendo o extrato vegetal e suas interações com as partículas iniciais influenciaram significativamente o processo. Os grânulos formados em leito fluidizado apresentaram ótima fluidez e maior retenção de polifenóis que os produtos obtidos por spray drying. Pellets de celulose microcristalina de diferentes granulometrias foram utilizados como partículas semente para investigar a dinâmica do sistema durante a encapsulação/aglomeração em leito fluidizado, por meio de análises de sinais de flutuação de pressão associados à cinética de crescimento dos grânulos e ao desempenho do processo. Dois modos operacionais foram avaliados: o modo intermitente (com interrupção da atomização da composição de alimentação em um período específico para redução do teor de umidade no sistema) e o modo contínuo (sem interrupção da atomização de alimentação). O aumento na porcentagem de aglomeração, até certo valor durante o processo, ocasionou aumento no desvio padrão nos sinais da amplitude da flutuação de pressão enquanto o sistema permaneceu estável, indicando poucas mudanças no padrão de circulação de sólidos. Este comportamento ocorreu até que a porcentagem de aglomeração atingiu um valor capaz de ocasionar instabilidades no sistema e, assim, o aumento adicional na percentagem de aglomeração acarretou o colapso do sistema. Neste momento, o desvio padrão da amplitude da flutuação de pressão tende a diminuir, sendo este comportamento mais evidente no modo operacional contínuo e com partículas semente de menor granulometria. Mudanças no desvio padrão da amplitude dos sinais da flutuação de pressão evidenciam que este método é capaz de detectar alterações na dinâmica do sistema e pode ser uma ferramenta útil para o controle e monitoramento do processo. Ensaios para avaliação da influência de diferentes variáveis operacionais, vazão de atomização e velocidade do ar de fluidização, no desempenho do processo foram realizados em modo operacional intermitente utilizando pellets de celulose microcristalina como partículas sementes. As condições operacionais mais adequadas, com maior eficiência de revestimento e menor porcentagem de aglomeração, foram selecionadas para avaliação de duas composições de alimentação contendo extrato vegetal com diferentes agentes de encapsulação, goma Arábica e concentrado proteico de soro de leite, associados à maltodextrina, ácido esteárico e Poloxamer 407. O desempenho dos processos foi avaliado através da eficiência de revestimento e porcentagem de aglomeração e os produtos quanto à fluidez e teor de compostos bioativos do alecrim: ácido cafeico, ácido rosmarínico, carnosol e ácido carnósico, determinados por HPLC-DAD. As duas formulações mostraram-se adequadas quanto ao desempenho do processo, eficiência de revestimento maior que 70% e à retenção de compostos bioativos, eficiência de encapsulação maior que 60%. Os grânulos foram submetidos testes de estabilidade acelerada e de longa duração. Os compostos bioativos sofreram degradação durante os testes com perda total de carnosol e ácido carnósico nos grânulos obtidos com as duas formulações diferentes. Também foi realizado teste de digestão gastrointestinal in vitro com os dois produtos diferentes. As concentrações de ácidos cafeico e rosmarínico não sofreram alterações significativas no decorrer do processo, tanto na simulação das condições gástricas quanto intestinais. O carnosol e o ácido carnósico sofreram perda total ao final da fase intestinal nos dois tipos de grânulos. Os grânulos com diferentes agentes encapsulantes, foram revestidos com Opadry® II visando proporcionar maior estabilidade contra degradação dos compostos bioativos. Ocorreu maior proteção do carnosol nos grânulos contendo goma Arábica submetidos ao teste de estabilidade de longa duração, a 30 °C e 75 % UR, porém esta proteção não foi efetiva para nenhum dos grânulos submetidos ao teste de estabilidade acelerada a 40 °C. Este estudo demonstrou a viabilidade do processo de encapsulação de extratos vegetais em leito fluidizado como um método promissor para produção de composições fitoterápicas com propriedades farmacotécnicas e físico-químicas adequadas. / This work aimed to investigate coating/agglomeration process of herbal extracts in fluidized bed with top spray atomization in order to improve stability of bioactive compounds and their pharmacotechnical properties. Crystal sugar granules, sugar and microcrystalline cellulose pellets, microcrystalline cellulose, cassava flour and rice granules, were used as seed particles. First, coating/agglomeration processes with cassava flour and sugar pellets as seed particles and feed compositions loaded with herbal extract of Rosmarinus officinalis (rosemary) were investigated. Fluidized bed performance was evaluated based on coating efficiency and agglomeration percentage. Products were characterized by determining the particle sizes, flow properties and retention of bioactive compounds (polyphenols). Herbal compositions were also spray dried to compare the product generated by both processes. Results showed that coating efficiency and percentage of agglomeration depend on seed particles and feed compositions physicochemical properties. The viscosity of the feed formulations and the interaction with seed particles influenced process performance. Fluidized bed granules exhibited higher efficiency of coating/agglomeration, higher retention of bioactive compounds and better flow properties than the powder obtained by spray drying. Microcrystalline cellulose pellets of different sizes were used as seed particles to investigate system dynamic during fluidized bed encapsulation/agglomeration by analysis of pressure fluctuation signals associated with growth kinetics and process performance. Two distinct operating modes were investigated: intermittent (interrupting the composition atomization for a specific period of time in order to reduce the system humidity) and continuous (without interruption of feed atomization). The increase in the agglomeration percentage to a certain value during the processes caused an increase in the standard deviation of the amplitude of the pressure fluctuations signals while the system remained stable, indicative of slight change on solids circulation patterns. However, the standard deviation of the amplitude of the pressure fluctuations signals tended to decrease when agglomeration percentage reached a value able to affect significantly the system stability, in which agglomerates growth tended to cause the system collapse. This behavior was most evident for small size seed particles and continuous operating mode. The changes in the standard deviation of the amplitude of pressure fluctuation signals showed strong evidence that this method would be able to detect changes in system dynamics and can be a useful tool for process control and system monitoring. Different operational variables, feed flow rate and fluidizing air flow rate, were used to analyze fluidized bed performance using intermittent mode and microcrystalline cellulose pellets as seed particles. Operating conditions that promoted higher coating efficiency and lower percentage of agglomeration were selected to be used in processes to evaluated different feed compositions loaded with herbal extract and encapsulating agents of two types, Arabic gum and whey protein, associated with stearic acid and poloxamer 407. Process performance was evaluated by coating efficiency and percentage of agglomeration. Products were evaluated by flow properties and the retention of bioactive compounds: cafeic acid, rosmarinic acid, carnosol and carnosic acid, determined by HPLC-DAD. Both compositions presented high coating efficiency and retention of bioactive compounds. Products were submitted to accelerated and long-term stability tests. Bioactive compounds of all granules suffered degradation during the tests with total loss of carnosol and carnosic acid. In vitro gastrointestinal digestion assays were carried out with the two types of products obtained. The concentrations of caffeic and rosmarinic acids did not change significantly during the digestion process, both in the simulation of gastric as intestinal conditions. The carnosol and carnosic acid have undergone total loss at the end of the intestinal phase in both types of products. The two types of granules with different encapsulating agents, were coated with Opadry® II aiming to provide greater stability against degradation of bioactive compounds. Higher protection of carnosol occurred in the granules containing gum Arabic subjected to long term stability test at 30 ° C, 75% RH, but this protection was not effective for any of the granules subjected to accelerated stability testing at 40 °C. The results provide strong evidence of the feasibility of the fluidised bed as a promising method for production of encapsulated phytopharmaceutical compositions with adequate pharmacotechnical and physicochemical properties.
5

Elaboração e caracterização de biomateriais granulados microporosos de fosfatos de cálcio: teste in vivo em ovinos / Elaboration and synthesis of granulates biomaterials of calcium phosphates: in vivo test in sheep

Dalmonico, Gisele Maria Leite 20 November 2015 (has links)
Made available in DSpace on 2016-12-08T15:56:19Z (GMT). No. of bitstreams: 1 Gisele Dalmonico.pdf: 8818399 bytes, checksum: 54cd754bf0a330bb5a3710ceaea2c8ed (MD5) Previous issue date: 2015-11-20 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Treatments for bone loss are research topics and involve different areas of scientific knowledge, engineering, physics, chemistry, biology and biomedicine. The biomaterials that stand out as replacement in bone structure treatments are hydroxyapatite, β and α calcium phosphate, biphasic hydroxyapatite/calcium phosphate β and α and hydroxyapatite matrix nanocomposite biomaterials. These biomaterials stand out as bone substitutes because they present a crystallography similar to that of human skeleton bone apatite, being bioactive and biocompatible. Nanostructured biphasic bioceramics are researched and show potential to be bone substitutes in surgical repairing procedures and reconstruction of bone tissue. This project was developed based on research of biomaterials of calcium phosphates, involving the synthesis of two matrices of calcium phosphates: β-calcium phosphate (β-TCP) and hydroxyapatite (HA) and the preparation of microporous granular biomaterials of β-TCP, HA and biphasic compositions HA/β-TCP. All biomaterials were characterized by different techniques: X-ray diffraction, infrared spectroscopy in Fourier transform (FTIR), Raman spectroscopy, specific surface area for BET, particle size by laser diffraction, density of helium pictometria, porosimetry mercury and hydrostatic porosity by Arthur, differential scanning calorimetry, dilatometry, scanning electron microscopy, atomic force microscopy, confocal microscopy, optical microscopy, polarized light microscopy. The interest of this research was to evaluate the performance of biomaterials in in vivo tests for the time periods of 90 and 180 days, in relation to osseointegration and the formation of neoformed bone tissue and determine which biomaterials presented potential as bone replacement for biomedical applications. The results found are encouraging and demonstrate that the granulated microporous biomaterials of calcium phosphate proves to be ability to repair and bone reconstruction for the two test times in vivo evaluated, revealing the osseointegration and bone formation similar between the compositions. / Os tratamentos de perdas ósseas são temas de pesquisa que envolve diferentes áreas do conhecimento científico, engenharia, física, química, biologia e biomédica. Os biomateriais que se destacam como substitutos em tratamentos da estrutura óssea são a hidroxiapatita, os fosfatos de cálcio-β e α, os bifásicos hidroxiapatita/fosfato de cálcio-β, α e os biomateriais nanocompósitos de matriz hidroxiapatita. O destaque destes biomateriais como substitutos ósseos, se deve, por apresentarem cristalografia similar à da apatita óssea do esqueleto humano, por serem bioativos e biocompatíveis. As biocerâmicas bifásicas nanoestruturadas são pesquisadas e demonstram ser promissoras como substitutos ósseos em procedimentos cirúrgicos de reparação e reconstrução do tecido ósseo. Este projeto se desenvolveu com base na investigação de biomateriais de fosfatos de cálcio, envolvendo a síntese de duas matrizes de fosfatos de cálcio: Fosfato de cálcio-β (TCP-β) e hidroxiapatita (HA) e elaboração de biomateriais granulados microporosos de TCP-β, HA e bifásicos HA/TCP-β. Todos os biomateriais granulados foram caracterizados por diferentes técnicas: difratometria de raios X, espectroscopia de infravermelho por transformada de Fourier (FTIR), espectroscopia Raman, área superficial específica por BET, tamanho de partícula por difração a laser, densidade por pictometria de hélio, porosimetria de mercúrio e hidrostática com método de Arthur. Com relação ao comportamento térmico utilizou-se a calorimetria exploratória diferencial, dilatometria. A caracterização microestrutural foi realizada com a microscopia eletrônica de varredura, microscopia de força atômica, microscopia confocal, microscopia óptica, microscopia de luz polarizada. Esse projeto de pesquisa envolveu a elaboração de biomateriais granulados microporosos de fosfatos de cálcio, o interesse foi avaliar o desempenho destes em teste in vivo, para os tempos de 90 e 180 dias em tíbia de ovinos, em relação ao desempenho dos mesmos sobre a osseointegração e a neoformação do novo tecido ósseo. Os resultados encontrados são animadores e demonstram que todas as composições de biomateriais granulados microporos de fosfatos de cálcio, demonstraram capacidade de reparação e reconstrução óssea para os dois tempos de teste in vivo avaliados, revelando a osseointegração e a neoformação óssea semelhante entre as composições.
6

Observational Aspects Of Core Collapse Supernovae

Gurugubelli, Uday Kumar January 2010 (has links) (PDF)
The discovery of several bright supernovae (SNe) in recent years has evoked a great deal of interest in these objects. The study of these objects are of importance not only as probes to the end stages of stellar evolution, but also as probes for cosmology. Though the basic classification of supernovae was restricted to type I and type II, pecularities became apparent over the last two decades that have been confirmed into new classes, currently designated as types Ia, Ib, Ic, IIL, IIP, IIn and IIb. Diversity in the behaviour of supernovae within a class has also become apparent, such as photometric and spectroscopic sequence in type Ia, and the existence of the super-luminous‚ hypernovae‚ which, at times are found to be associated with GRB events. Core collapse supernovae are the end stages of most stars, more massive than ~ 8M . As such, they provide a key test of stellar evolution. Further, they play a major role in driving the chemical and dynamical evolution of galaxies, and have also been proposed to be major contributors to dust epochs when the Universe was still young. SNe explosions provide unique natural laboratories for studying, in real time, the physics of a variety of combustion, hydrodynamic, nuclear and atomic processes. All subclasses of SNe, except for type Ia, are core collapse events. The differences in the observed properties of the various subclasses, and even within a single subclass, may be attributed to the progenitor mass, metallicity and environment. The light curve and the spectral development would enable obtaining certain critical parameters related to the progenitor. It is hence important to study individual SNe events. The aim of this work is to (a) study the individual objects in detail and obtain critical parameters such as the radioactive Nickel mass ejected during the explosion, the mass of the ejected material, velocity with which the material has been ejected, the explosion energy and the distance to the supernova; (b) estimate progenitor mass and radius; (c) group the individual events according to certain common properties and inter-compare the properties of the various groups to arrive at a possible evolutionary sequence of the progenitors. This thesis consists of 6 chapters. Chapter 1 gives a general introduction to the evolution of massive stars and supernovae. Chapter 2 describes the telescope and instrument, observations and reduction procedures. All data were obtained using the 2m Himalayan Chandra Telescope (HCT), Hanle, India. The technical details of telescope and instrument are given in the chapter. This chapter also discusses in detail the various techniques used in photometric and spectroscopic data reductions. Chapter 3 discusses the properties of Type IIP supernovae with a detailed study of SN 2004A and SN 2008in. The distances to the supernovae are estimated using the Standard Candle Method (SCM) (Hamuy & Pinto, 2002) and the Expanding Photosphere Method (EPM)( Krishner & Kwan, 1974, 1975, Hamuy et al. 2001) . In addition, the explosion energy, radius of progenitor, the nickel mass and the mass ejected during the explosion are estimated using the observed light curves and the spectra (Hamuy 2003, Elmahamdi 2003, Litvinova & Nadyozhin 1985). The progenitor mass is also estimated based on the estimate of the ejected mass. Chapter 4 describes the evolution of the Type IIn supernova SN2005kd, which is characterized by narrow emission lines in the early spectra. Some Type IIn supernovae show a plateau phase in the light curve, and SN 2005kd is of this kind. The narrow emission lines in the spectra show that the SN ejecta interacted with the pre-supernova circumstellar material that is a result of mass loss from the progenitor during its evolution. Chapter 5 discusses the properties of stripped envelope core collapse supernovae using the observations of type Ib/c supernovae SN 2006jc, SN 2007ru, and SN 2009jf. SN 2006jc was found to be peculiar, with narrow He I emission lines arising due to the SN ejecta interaction with a helium enriched pre-supernova circumstellar material. SN 2007ru shows very broad lines in the spectra indicating a velocity of 20,000 kms−1 . The light curve evolution of SN 2007ru indicates a fast rise time and post-maximum decline more rapid than other broad-line Ic supernovae. The light curves of SN 2009jf are broad, with slow decline, indicating the presence of massive ejecta. He I line is identified with velocity of 16,000 km−1 . The photometric and spectroscopic evolution of all the above SNe are described in detail and compared with other similar supernovae. The various physical parameters related to the explosion and progenitors of SNe are also estimated. Chapter 6 is devoted to conclusions and future plans for the work in this thesis.
7

Propriétés nutritionnelles et fonctionnelles des protéines de tourteaux, de concentrats et d'isolats de Ricinodendron heudelotii (Bail.) Pierre ex Pax et de Tetracarpidium conophorum (Müll. Arg.) / Nutritional and functional properties of proteins from defatted flours, concentrates and isolates of Ricinodendron heudelotii (Bail.) Pierre ex Pax and Tetracarpidium conophorum (Müll. Arg)

Mezajoug Kenfack, Laurette Blandine 07 April 2010 (has links)
Cette étude a été menée dans le but d’explorer les nouvelles sources de protéines à valeur nutraceutique. Les graines de Ricinodendron heudelotii (Bail. Pierre ex Pax) et de Tetracarpidium conophorum (Müll. Arg) ont d’abord été cuites dans de l’eau bouillante pendant 90 et 30 min qui sont respectivement leurs temps optimums de cuisson. Après délipidation et tamisage des tourteaux, la fraction 400 - 500 µm s’est révélée la plus représentative avec plus de 70 % et riche en azote protéique (6–7% MS). Les concentrats et les isolats protéiques ont été préparés à partir des tourteaux respectivement dans l’eau distillée à pH 4,5 et dans une solution de NaOH à 0,2 % (R. heudelotii), une solution de NaCl 0,6 M (T. conophorum) à pH 11. Ces concentrats (65 – 75 % MS de protéines) et ces isolats protéiques (81 – 92 % MS de protéines) ont une composition physico-chimique différente (P < 0,05) de celle des tourteaux. Pour les deux Euphorbiacées, les capacités de rétention d’eau (367 – 467 g / 100 g d’échantillon), de rétention d’huile (256 – 410 g / 100 g d’échantillon) et moussante (68 – 71 %) sont maximales dans les isolats protéiques tandis que les capacités gélifiante (6 – 14 %) et émulsifiante (63 – 87 %) le sont dans les concentrats protéiques. Les teneurs en acides aminés essentiels des tourteaux de R. heudelotii et de T. conophorum sont comparables à celle de la protéine de référence. L’étude de la digestibilité enzymatique in vitro a montré que l’azote libéré après 6 h est supérieur à 90 % dans les concentrats et les isolats protéiques. La digestibilité protéique in vivo indique que le gain de poids des rats mâles âgés de 21 ± 3 jours durant 15 jours d’expérimentation ainsi que les paramètres de rétention azotée sont plus importants avec les régimes à base de l’aliment de référence (caséine) et du tourteau de T. conophorum. Les valeurs corrigées des paramètres de digestibilité par l’indice chimique des acides aminés laissent apparaître que le tourteau de T. conophorum renferme les protéines de très bonne qualité nutritionnelle, autant que la caséine / This study was conducted in order to look for alternative sources of proteins having nutraceutic value. The grains of Ricinodendron heudelotii (Bail.) and Tetracarpidium conophorum (Müll. Arg) were first cooked in boiled water at their optimal cooking time for 90 and 30 min respectively. After defating, sieving of the defatted cakes showed that samples with a granulometry of 400 - 500 µm were most representative (more than 70%), containing more proteic nitrogen (6–7 %). Protein concentrates and protein isolates were prepared from defatted cakes respectively in distilled water at pH 4.5 and in NaOH 0.2% (R. heudelotii) and NaCl 0.6M (T. conophorum) at pH 11. Physico-chemical properties of protein concentrates (65 – 75 % of proteins) and protein isolates (81–92 % of proteins) were different from those of the defatted cakes. Water holding (367 – 467 g / 100 g of sample), oil holding (256 – 410 g / 100 g of sample) and foaming capacities (68 – 71 %) were highest with protein isolates whereas gelling (6 – 14 %) and emulsion capacities (63 – 87 %) were highest with concentrates. The amounts of essential amino acids in both defatted flours were comparable to the value in FAO / WHO (2007) scoring pattern. Nitrogen liberated after 6 h of enzymatic digestibility was more than 90 % both in the proteins concentrates and isolates. In vivo studies carried out on 21 ± 3 days old Sprague Dawley male rats for 15 days showed that gain of weight and nitrogen retention parameters were higher for rats that consumed casein and T. conophorum defatted cake. Corrected values of nitrogen digestibility of the analysed samples showed that T. conophorum defatted cake contains protein source with good nutritional quality

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