Дисертації: "Liquid extraction purification"

1

Pinheiro, Regiane Silva. "Study of liquid-liquid extraction for methyl biodiesel purification process." Universidade Federal do CearÃ, 2013. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=14103.

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CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior
In the process of purification of biodiesel is of extreme importance washing methyl or ethyl ester rich- phase, since in conventional processes there is a great amount of water. During the washing is extracted primarily excess alcohol. Composition data for the washing process of biodiesel is still scarce in the literature and the study of liquid-liquid equilibrium provides the means to develop equipment and to optimize the extraction processes. Thus the main goal of this work is to determine equilibrium data for three different ternary systems: water - methanol - soybean biodiesel; corn biodiesel â methanol â water; methanol - coconut biodiesel - water at 20 Â C and 40 Â C. The experiments were carried out in equilibrium cells where the temperature was kept constant by thermostat control. The experimental determination was made by the method of densimetry. The consistency of data obtained for the tie lines was verified by correlations. It was verified by the ternary graphs, little influence of temperature on the systems studied. The equilibrium data were correlated liquid-liquid models for the activity coefficient NRTL, UNIQUAC and UNIFAC and proved quite satisfactory.
No processo de purificaÃÃo do biodiesel, a lavagem da fase rica em metil ou etil Ãster Ã de extrema importÃncia, visto que nos processos convencionais hÃ um grande gasto de Ãgua. Durante a lavagem Ã extraÃdo principalmente Ãlcool em excesso. Dados de composiÃÃes para a lavagem de biodiesel ainda sÃo escassos na literatura e o estudo do equilÃbrio lÃquido-lÃquido pode fornecer meios para o desenvolvimento de equipamentos e otimizaÃÃo dos processos de extraÃÃo. Dessa forma, o principal objetivo dessa dissertaÃÃo foi determinar dados de equilÃbrio lÃquido- lÃquido para os sistemas ternÃrios contendo biodiesel de soja + metanol + Ãgua, biodiesel de milho + metanol e Ãgua e biodiesel de coco + metanol + Ãgua, a 20 ÂC e 40 ÂC. Os experimentos foram feitos em cÃlulas de equilÃbrio mantendo a temperatura constante. A determinaÃÃo experimental das misturas ternÃrias foi feita pelos mÃtodos de titulaÃÃo e densimetria. A consistÃncia dos dados das linhas de amarraÃÃo foi verificada pelas correlaÃÃes de Othmer-Tobias e Hand. Verificou-se por meio de grÃficos ternÃrios, pouca influÃncia da temperatura sobre os sistemas estudados. Os dados de equilÃbrio lÃquido-lÃquido foram correlacionados pelos modelos para coeficiente de atividade NRTL, UNIQUAC e UNIFAC e mostraram-se bastante satisfatÃrios.

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2

Hewitson, Peter. "Intermittent counter-current extraction : a new continuous dynamic liquid-liquid extraction methodology." Thesis, Brunel University, 2014. http://bura.brunel.ac.uk/handle/2438/13900.

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For the pharmaceutical industry, the manufacture of high value pharmaceuticals from natural products, chemical synthetic routes or fermentation processes all require intensive downstream processing steps to produce a pure final product. A small footprint liquid-liquid processing method would help to reduce the capital cost and process development time of this downstream processing. In this thesis, it is hypothesised that continuous liquid-liquid extraction can be achieved using a standard hydrodynamic counter-current chromatography (CCC) instrument by switching the flow of the liquid phases between normal phase and reversed phase intermittently, so separating a feed stream into two eluant flows. A model of the process was derived and tested on three scales of instrument, from the semipreparative to the pilot scale. The method developed, Intermittent Counter-current Extraction (ICcE) was compared to dual-flow counter-current chromatography (DFCCC), the classical method of applying continuous extraction using a counter-current chromatograph. ICcE was found to be advantaged due to the more stable phase volume ratio achievable in the columns and the ability to operate the procedure on standard commercial twin-column CCC instruments which operate at high g-field. The robustness of the ICcE method was successfully demonstrated across a range of phase system polarities and at high throughput (1kg/day on a preparative instrument) with model mixtures of pharmaceutical compounds. The effectiveness of this new processing method was confirmed on three industrially relevant case studies. Firstly a polar extract from natural senna pods to extract important sennosides, secondly an intermediate polarity highly complex active pharmaceutical ingredient waste stream to recover the main active component and thirdly a non-polar natural product extract to recover macrocarpal compounds. In summary, the ICcE method now offers another tool in the range of liquid-liquid separation methods available to the pharmaceutical and other high value industries.

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3

Campos, Assunção Mariana. "Etude physicochimique et formulation d'un nouveau solvant d'extraction pour la purification de l'acide phosphorique." Thesis, Paris 6, 2017. http://www.theses.fr/2017PA066045/document.

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Cette thèse avait pour objectif de développer de nouveaux systèmes d’extraction liquide-liquide compatibles avec le procédé Prayon pour la purification de l’acide phosphorique produit par voie humide. Une étude bibliographique complète des solvants d’extraction étudiés dans la littérature pour l’extraction liquide-liquide de l’acide phosphorique nous a permis d’identifier des candidats potentiellement intéressants. Une étude approfondie des propriétés d’extraction de ces systèmes et de leur sélectivité vis-à-vis des espèces métalliques nous a finalement permis de nous focaliser par la suite sur trois solvants d’extraction : le dibutyl éther (DBE), le diisobutyl carbinol (DiBC) dilué dans le diisopropyl éther (DiPE) et la Fentamine T0810 (ATS) dilué dans le DiPE. La formulation de ces mélanges a ensuite été optimisée en veillant à étudier le comportement de ces systèmes à chaque étape du procédé d’extraction liquide-liquide, c’est à dire l’extraction, la désextraction et le lavage. Cette étude a également permis de fixer les conditions opératoires optimales, notamment le rapport des volumes des phases. Au cours de cette étude, des phénomènes complexes de transitions de phases réversibles de la phase organique de monophasique vers biphasique (formation de troisième phase) et biphasique vers monophasique (retour à une phase organique unique) ont été mis en évidences expérimentalement. Pour finir, un modèle physicochimique d’extraction fondé sur des bilans de masse a été développé. Ce modèle s’avère très utile pour décrire l’extraction de l’acide phosphorique et de l’eau et la variation des volumes des phases au cours de l’extraction
This PhD thesis was focused on the development of new extraction systems to purify phosphoric acid from wet phosphoric acid (WPA). The new system should be respectful of the current Prayon’s process flowsheet designed for the use of the mixture tri-n-butyl phosphate(TBP) and diisopropyl ether (DiPE) as extraction solvent. Firstly, extractants exhibiting different structures and functional groups were screened in order to assess their efficiency and selectivity towards phosphoric acid. Three new promising extraction systems were identified: diisobutyl ether (DBE), diisocarbinol (DiBC) in DiPE, and Fentamine T0810 (ATS) in DiPE. Secondly, our effort was directed to the comprehension of the physico-chemical phenomena involved in the extraction of phosphoric acid by the mixture TBP/DiPE at first, and enriched to describe the other systems studied later. Finally, a simulation model describing the solvent extraction of phosphoric acid by the solvent currently employed by Prayon is presented. This model accounts for the significant volume variation during the extraction of phosphoric acid and allows performing optimizations of extraction parameters even at very high phosphoric acid concentrations (6-14M)

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4

Alenazi, Mohrah. "Extraction and Purification of Biologically Active Metabolites from Rhodococcus sp. MTM3W5.2." Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/etd/3507.

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Rhodococcushas been recognized as a potential antibiotic producer. Recently, a strain of Rhodococcussp. MTM3W5.2 was isolated from a soil sample collected in Morristown, Tennessee and was found to produce an inhibitory compound which is active against other related species. The purpose of this research is to extract, purify and analyze the active metabolite. The compound was extracted from RM broth cultures and purified by preliminary fractionation of crude extract through a Sephadex LH-20 column. Further purification was completed using semi-preparative reversed phase column chromatography. Final purification was obtained using multiple rounds of an analytical C18 HPLC column. Based on the results achieved in the UV-Vis spectroscopy and high-resolution mass spectroscopy, the two desired compounds at a retention time of at 57 and 72 min could be polyketides with the molecular formulas C52H78O13 and C19H32O1N1/C13H34O1N1, respectively.

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5

Gilbert, Christopher Donald. "Non-Newtonian conversion of emulsion liquid membranes in the extraction of lead and zinc from simulated wastewater." Diss., Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/10911.

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6

Lane, Marshalle. "Dispersive liquid-liquid micro-extraction coupled with gas chromatography for the detection of trihalomethanes in different water sources in the Western Cape, South Africa." Thesis, Cape Peninsula University of Technology, 2018. http://hdl.handle.net/20.500.11838/2852.

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Thesis (MTech (Chemistry))--Cape Peninsula University of Technology, 2018.
Trihalomethanes (THMs) are a group of four compounds that are formed, along with other disinfected by-products. This happens when chloride or other disinfectants are used to control microbial contamination in drinking water, which then reacts with natural organic or inorganic substances in water. Trihalomethanes are better known by their common names such as chloroform, bromodichloromethane, chlorodibromomethane and bromoform. These four compounds are known to be classified as cancer group B carcinogens (shown to cause cancer in laboratory animals). Trihalomethane levels tend to increase with pH, temperature, time and the level of “precursors" present. Precursors are known to be organic substances which react with chloride to form THMs. One significant way of reducing the amount of THMs in water is to eliminate or reduce chlorination before filtrations and reduce precursors. There are guideline limits for THMs in the SANS 241:2015 document, but they are not continuously monitored and their levels in natural water are not known. The aim of this study is to develop a rapid, fast and reliable liquid-liquid microextraction technique, to determine the presence of THMs in natural water sources. This study particularly focuses on different water sources e.g. river, underground, borehole and chlorinated water. Chlorinated water is the water that has been presumably treated for bacteria and fungus growth. The results that were obtained for chlorinated water are as follow, 10.120 μg/L − 11.654 μg/L for chloroform, 2.214 μg/L - 2.666 μg/L for bromodichloromethane, 0.819 μg/L − 0.895 μg/L chlorodibromomethane and 0.103 μg/L - 0.135 μg/L for bromoform from validation data. All these THMs concentrations have been found to be below the SANS 241:2015 limits. Natural water shows a very high affinity for chloroform. This is what is expected under normal conditions as chloroform is the most abundant THM of all THMs present in natural water. The liquid-liquid microextraction technique that was optimized and used for the determination of THMs in this study is a rapid, simple and inexpensive technique that provides low limits of detection (LOD) e.g. 0.1999 μg/L chlorodibromomethane and 0.2056 μg/L bromoform and wide dynamic range (LOQ) of 0.6664 μg/L chlorodibromomethane and 0.6854 μg/L bromoform for the determination of THMs.

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7

Manikindi, Pushpavathi Reddyvari. "Extraction, Purification and Characterization of an Antibiotic-like Compound Produced by Rhodococcus sp. MTM3W5.2." Digital Commons @ East Tennessee State University, 2016. https://dc.etsu.edu/etd/3116.

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The bacterium Rhodococcus is a potential source for novel antimicrobial metabolites. Recently, the Rhodococcus strain MTM3W5.2 was isolated from a soil sample collected from Morristown, East Tennessee and was found to produce an inhibitor molecule that is active against similar Rhodococcus species. The aim of this research is to extract, purify, and characterize the active compound. The compound was obtained from both agar and broth cultures of strain MTM3W5.2 and purified by primary fractionation of crude extract on a Sephadex LH-20 column, followed by semi-preparative reversed phase column chromatography. Final purification was achieved using multiple rounds of an analytical C18 HPLC column. Based on the results obtained from UV-Vis, FT-IR, and HR-MS, the molecule is a polyketide with a molecular formula of C52H78O13 and an exact mass of 911.5490 amu. The partial structure of this compound has been determined using 1D and 2D NMR spectroscopy.

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8

Pereira, Matheus Mendonça. "Ionic-liquid-based aqueous biphasic systems as concentration and purification platforms of cancer biomarkers." Doctoral thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/21532.

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Doutoramento em Engenharia Química
Cancer is worldwide a major cause of death, with ca. 14 million new diagnosed cases each year. Therefore, the search for more efficient early-stage diagnosis methods is crucial aiming at increasing the treatment rate and survival of patients, as well as to decrease the expenses associated to advanced treatment. Prostate specific antigen (PSA) and lactate dehydrogenase (LDH) are proteins commonly found in human fluids (urine and serum), and have been considered as cancer biomarkers and in the monitoring of cancer treatment. However, due to their low concentration and the complexity of biological matrices with a large amount of other metabolites present (proteins, DNA, RNA), the pretreatment of samples for their concentration and purification is usually applied. In this work, alternative pretreatment techniques based on aqueous biphasic systems (ABS) composed of ionic liquids (ILs) have been studied to extract, concentrate and purify proteins that can be used as cancer biomarkers, such as PSA and LDH. To this end, several preliminary works were performed to identify the most promising phase-forming components and conditions to create ABS that could be used for the extraction of proteins. These works comprise studies on the extraction of amino acids and model proteins in ABS, followed by investigations on their use with more complex matrices. Finally, ABS were investigated for the extraction and concentration of tumor biomarkers, namely PSA and LDH. In summary, the versatility of ILs allows the tailoring of the ABS extraction and concentration capacity, selectivity, and/or induced precipitation of cancer biomarkers from human fluids. The systems here developed are a viable and efficient alternative for the pretreatment of biological samples (serum and urine), thus contributing to the development of early-stage methods of cancer diagnosis.
O cancro é mundialmente uma das principais causas de morte, com cerca de 14 milhões de novos casos diagnosticados por ano. Neste sentido, o desenvolvimento de métodos de diagnóstico mais eficientes em estágio inicial da doença é crucial para auxiliar o tratamento e aumentar a taxa de sobrevida dos pacientes, além de diminuir as despesas associadas aos tratamentos avançados. O antígeno específico da próstata (PSA) e a lactato desidrogenase (LDH) são proteínas comumente encontradas nos fluidos humanos (urina e soro) e têm sido alvo de atenção como biomarcadores do cancro e na monitorização do seu tratamento. No entanto, devido à sua baixa concentração e à complexidade das matrizes biológicas com uma grande quantidade de outros metabólitos presentes (proteínas, DNA, RNA), é geralmente aplicado um ou mais passos de pré-tratamento de amostras. Neste trabalho, foram estudadas técnicas alternativas de pré-tratamento baseadas em sistemas aquosos bifásicos (SAB) constituídos por líquidos iónicos (LIs) para extrair, concentrar e purificar proteínas que podem ser usadas como biomarcadores de cancro, como a PSA e LDH. Para este fim, foram realizados vários trabalhos preliminares para identificar os componentes e condições de formação mais promissores para criar SAB que possam ser utilizados para a extração de proteínas. Estes trabalhos contemplam a utilização de SAB para a extração de aminoácidos e proteínas modelo, assim como a utilização de SAB em matrizes mais complexas. Finalmente, os SAB foram aplicados para a extração e concentração de biomarcadores tumorais, nomeadamente PSA e LDH. Em suma, com este trabalho verificou-se que a versatilidade dos LIs permite adaptar a capacidade de extração e concentração, seletividade, e/ou precipitação induzida de biomarcadores de cancro a partir de fluidos humanos. Os sistemas aqui desenvolvidos são uma alternativa viável e eficiente para o pré-tratamento de amostras biológicas (soro e urina), contribuindo assim para o desenvolvimento de métodos de diagnóstico de cancro precoces.

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Duran, Renan Ravetti. "Procédés d’extraction et de purification de molécules à haute valeur ajoutée issues de la biomasse bois." Thesis, Université de Lorraine, 2015. http://www.theses.fr/2015LORR0325.

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Les sous-produits qui proviennent de l’industrie du bois, particulièrement les nœuds, contiennent différents types de molécules qui peuvent être valorisées comme source de composants bioactifs pouvant répondre à des besoins thérapeutiques. C’est sur cette idée que le projet "Le Bois Santé" a été conçu. Grâce à la collaboration de plusieurs partenaires, le présent travail vise dans un premier temps à développer des procédés d’extraction "verts" (solide-liquide et supercritique) pour obtenir un extrait riche en lignanes à partir d’un mélange de nœuds d’épicéa commun et de sapin pectiné. Les effets des conditions opératoires sur le rendement d’extraction de chaque composé cible et sur l’activité anti-oxydante des extraits ont été déterminés. Afin d’étudier le procédé complet, le projet vise à étudier l’impact des procédés de concentration et de séchage de l’extrait à partir de l’évaporation sous vide et de la lyophilisation. De plus, la séparation et la purification des composés ont été développées et optimisées par simulation grâce à la technique de chromatographie frontale
By-products from wood industry, particularly knots, contain different types of molecules that can be valued as a source of bioactive components meeting therapeutic needs. It is on this idea that the project "Le Bois Santé" was designed. Through the collaboration of several partnerships, the present work aims initially to develop a "green" extraction processes (solid-liquid and supercritical) to obtain an extract rich in lignans from a mixture of norway spruce and silver fir knots. The effects of operating conditions on the extraction yield of each target compound and the antioxidant activity of the extracts were determined. To understand the entire process, the project aims to investigate the impact of concentration and drying processes using vacuum evaporation and lyophilisation. Moreover, the separation and purification of the compounds have been developed and optimized using frontal chromatography technique

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10

Gomes, Joana Margarida Mota. "Purification of IgY using aqueous biphasic systems composed of good’s buffers ionic liquids." Master's thesis, Universidade de Aveiro, 2015. http://hdl.handle.net/10773/15391.

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Mestrado em Bioquímica - Métodos Biomoleculares
The increased inefficiency of antibiotics observed in the past few years, derived from the growing number of drug-resistant organisms and the appearance of individuals with impaired immune system, led to a significant research on antibodies for use in passive immunotherapy. Antibodies obtained from the egg yolk of immunized hens, immunoglobulin Y (IgY), are a promising alternative to mammalian antibodies. They can be obtained in higher titres and by less invasive techniques, thus opening the door for a new kind of more economic biopharmaceuticals. However, the available techniques for the IgY extraction and purification are time-consuming, labor intensive, low yielding, provide low-purification levels, are of high cost and cannot easily be scaled-up for industrial applications. In this work, ABS composed of C6H5K3O7 and ILs synthetized by the combination of anions with buffer capacity (Good’s buffers), with the tetrabutylphosphonium ([P4444]+) and tetrabutylammonium ([N4444]+) cations, were investigated. The use of different ILs allowed the study of the cation and anion nature on the phase diagrams behaviour and thus on their ability to form ABS. Further, the ability of these systems as an alternative purification platform for IgY, by a selective extraction, was studied. The complete extraction and purification of IgY was not achieved in a single with the investigated ABS. However, the study of the proteins profile of the coexisting phases allowed to conclude that all proteins migrate for the top phase during the partitioning process, and that a complex between the ILs and the different proteins present in the water-soluble fraction of proteins from egg yolk was formed. Still, the results obtained reveal that the system composed of 20.1 wt % [N4444][CHES] + 16.9 wt % C6H5K3O7 is the most promising ABS for the IgY extraction.
Recentemente, a utilização de anticorpos para imunoterapia passiva tornou-se uma área de investigação atrativa. Tal facto deve-se à diminuição da eficiência dos antibióticos pelo aumento do número de organismos resistentes. Os anticorpos obtidos a partir da gema do ovo de galinhas imunizadas, imunoglobulinas Y (IgY), são uma alternativa viável e promissora aos anticorpos de mamíferos. Estes apresentam inúmeras vantagens, dado que podem ser obtidos em maior quantidade e serem recolhidos por técnicas menos invasivas. Apesar das vantagens apresentadas, as técnicas disponíveis para a extração e purificação de IgY são demoradas, trabalhosas, apresentam baixo rendimento, levam a baixos fatores de pureza, apresentam custos elevados e não são facilmente aplicáveis a nível industrial. Assim, o principal objetivo deste trabalho consistiu no desenvolvimento de uma plataforma de purificação alternativa para a extração e purificação de IgY, utilizando sistemas aquosos bifásicos (SAB) constituídos por líquidos iónicos com capacidade tampão. Neste trabalho foram estudados SAB constituídos por C6H5K3O7 e líquidos iónicos, sendo os últimos sintetizados pela combinação de aniões com capacidade tampão (Good’s buffers), com os catiões tetrabutilamónio ([N4444]+) e tetrabutilfosfónio ([P4444]+). Os líquidos iónicos utilizados permitiram o estudo da influência do anião e do catião nos diagramas de fase, ou seja sob a capacidade dos diferentes líquidos iónicos para formar SAB. De seguida, foi testada a capacidade destes sistemas como uma plataforma alternativa para a extração seletiva, e posterior purificação, de IgY. A purificação de IgY não foi conseguida num único passo de extração com os sistemas estudados. No entanto, o estudo do perfil proteico de ambas as fases dos sistemas permitiu concluir que, durante a partição, todas as proteínas migraram para a fase superior e que houve formação de um complexo entre o IL e algumas das proteínas constituintes da fração aquosa proteica da gema do ovo. Os resultados obtidos revelaram que, entre os vários SAB estudados, o mais promissor para a extração de IgY, é aquele constituído por 20.1 (m/m) % [N4444][CHES] + 16.9 (m/m) % C6H5K3O7.

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11

Mouhib, Mohamed. "Equilibres entre phases liquides et solides dans les systèmes H₂O-H₃PO₄-Solvant (DIPE ; TBP ; MIBK ; Hexane) en vue de la purification de l’acide phosphorique : Étude expérimentale et modélisation thermodynamique." Electronic Thesis or Diss., Lyon 1, 2024. http://www.theses.fr/2024LYO10276.

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L'acide phosphorique (H3PO4) est le deuxième acide inorganique le plus produit au monde, principalement utilisé dans la fabrication d'engrais. Cependant, son utilisation dans des applications technologiques de pointe, telles que l'industrie des semi-conducteurs, nécessite une pureté extrêmement élevée qui ne peut être obtenue qu’après élimination poussée des cations métalliques et matière organique dissous, dont l’origine est la roche phosphatée initiale. Pour optimiser la purification de l'acide phosphorique élaboré par voie humide (WPA), il est primordial de maîtriser les équilibres entre phases mis en jeu dans deux méthodes complémentaires et efficaces : l'extraction liquide-liquide et la cristallisation. Dans ce cadre, le présent travail est focalisé sur l’étude systématique et la modélisation des équilibres entre phases liquide-liquide, solide-liquide, liquide-liquide-solide impliquant l’acide phosphorique, l’eau et divers solvants organiques. La 1ère partie présente une analyse systématique des équilibres liquide-liquide des systèmes quaternaires (H2O-H3PO4-DIPE-TBP, H2O-H3PO4-DIPE-MIBK, et H2O-H3PO4-TBP-MIBK) pour évaluer l’effet synergique de ces solvants mixtes sur l'efficacité d’extraction de l'acide phosphorique. En outre, dans le système ternaire H2O-H3PO4-DIPE, l'efficacité est également évaluée en tenant compte de l'influence de l’addition des solvants TBP et MIBK sur la formation d’une troisième phase liquide. La deuxième partie se concentre sur l’étude des équilibres solide-liquide dans le système H2O-P2O5, incluant l'étude des systèmes binaires H2O-H3PO4 et H3PO4-H4P2O7 par des mesures de solubilité, calorimétrie et diffraction des rayons X. Cette étude permet de délimiter les domaines de stabilité de l’acide phosphorique et de ses hydrates, et de mettre en évidence l’existence de nouvelles phases stables, métastables, ainsi que d'éventuels polymorphismes. Ensuite, une modélisation par le modèle quasi-idéal permet d’affiner les données expérimentales et d'obtenir des informations sur la structure des solutions. Enfin, la troisième partie explore les équilibres liquide-liquide-solide (LLSE) du système H₂O- H3PO4-C6H14 en fonction de la température. Les données expérimentales sont modélisées dans le domaine de température entre 283.2 K et la température de fusion de l’acide phosphorique anhydre, offrant une représentation précise des équilibres de démixtion et des SLE dans tout le domaine de composition
Phosphoric acid (H3PO4) is the second most widely produced inorganic acid in the world, mainly used in fertilizer manufacturing. However, its use in advanced technological applications, such as the semiconductor industry, requires extremely high purity, which can only be achieved after extensive removal of dissolved metal cations and organic matter, from the original phosphate rock. To optimize the purification of wet-process phosphoric acid (WPA), it is essential to master the phase equilibria involved in two complementary and effective methods: liquid-liquid extraction and crystallization. In this context, the present work focuses on the systematic study and modeling of liquid-liquid, solid-liquid, and solid-liquid-liquid phase equilibria involving phosphoric acid, water, and various organic solvents. First part presents a systematic liquid-liquid equilibrium analysis of quaternary systems (H2O-H3PO4-DIPE-TBP, H2O-H3PO4-DIPE-MIBK, and H2O-H3PO4-TBP-MIBK) to assess the synergistic effect of these mixed solvents on phosphoric acid extraction efficiency. In addition, in the ternary H2O-H3PO4-DIPE system, the efficiency was also evaluated taking into account the influence of the addition of TBP and MIBK solvents on the formation of a third liquid phase. The second part focuses on the study of solid-liquid equilibria in the H2O-P2O5 system, including the study of the binary systems H2O-H3PO4 and H3PO4-H4P2O7 by solubility measurements, calorimetry and X-ray diffraction. This study delimits the stability domains of phosphoric acid and its hydrates, and highlights the existence of new stable, metastable phases, as well as possible polymorphisms. Then, the Quasi-ideal model was used to refine the experimental data and obtain information on the structure of the solutions. Finally, the third part explores the solid-liquid-liquid equilibria (SLLE) of the H2O-H3PO4-C6H14 system as a function of temperature. Experimental data was modeled from 283.2 K to the melting temperature of anhydrous phosphoric acid, providing an accurate representation of demixing equilibria and SLLE throughout the composition range

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Elias, Moacyr Jorge. "Determinação das condições de atividade otima, da estabilidade termica e da cinetica da hidrolise enzimatica de bromelina presente na casca e no talo do abacaxi (Ananas comosus L. Merril) variedade perola." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/267036.

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Orientador: Elias Basile Tambourgi
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica
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Resumo: A bromelina, enzima presente no abacaxi, hidrolisa ligações peptídicas das proteínas; tem aplicação em diversas áreas envolvendo alimentos, medicina e nutrição animal. No abacaxi a bromelina está presente no talo, na polpa e na casca do fruto. Visando avaliar a bromelina presente no fruto brasileiro Ananás comosus L. Merril, variedade pérola, enfocando seu aproveitamento quando recuperada a partir dos resíduos da industrialização, foram pesquisadas, em comparação com a bromelina pura, condições de pH e temperatura para maior atividade, estabilidade térmica ao longo do tempo em várias temperaturas e a cinética da sua atividade catalítica, empregando caseína como substrato. O extrato foi obtido pela trituração da casca e do talo interno do fruto e a reação de hidrólise, com pH controlado, efetuada em reator com 75 mL de volume útil sob constante agitação. Após a reação foi retirada amostra, adicionada em tubo contendo ácido tricloroacético e centrifugado, analisando a absorbância do sobrenadante. Atividade e a cinética foram expressas em mmol tirosina / L.minuto pela absorbância a 280 nm dos aminoácidos aromáticos gerados na hidrólise da caseína. Foram empregadas três relações enzima / substrato (em massa): 1 / 25, 1 / 50 e 1 / 125 para os ensaios relativos ao planejamento experimental em estrela tendo como ponto central pH em 7,0 e temperatura de 35 °C, os resultados foram tratados fornecendo as equações do modelo e as superfícies de resposta; as equações foram tratadas matematicamente fornecendo gráficos da melhor atividade em função da temperatura; os resultados do planejamento experimental mostraram similaridade entre a bromelina dos resíduos do fruto e a bromelina pura tomada como padrão. Para a estabilidade térmica os ensaios foram efetuados determinando a atividade para a relação 1 / 25 sob temperaturas variando entre 25 °C e 62 °C ao longo de 180 minutos com duas faixas de pH: a de melhor atividade definida no planejamento experimental (5,5 a 6,5) e entre 3,3 e 3,5; os resultados foram tratados analisando o gráfico da atividade em função do tempo mostrando que o modelo de ordem um é adequado para descrever a inativação térmica da enzima e que ela ocorre de maneira mais acentuada na faixa de pH 3,3 a 3,5 com valor do fator de freqüência k0 (minuto-1) 2,5 x1032 vezes maior para o extrato. Os ensaios para determinar a cinética da atividade catalítica da bromelina sobre a caseína foram efetuados a temperatura constante de 35 °C e pH de máxima atividade definido no planejamento experimental para cada uma das três relações enzima / substrato estudadas; foram elaboradas as curvas da concentração de aminoácidos formados ao longo do tempo (zero a 15 minutos) e os resultados tratados calculando a derivada das curvas no tempo zero (velocidade inicial); o modelo de Michaelis - Menten mostrou ser adequado para descrever o mecanismo de hidrólise da caseína pela bromelina e os resultados indicam que os valores da velocidade máxima (Vmax) e da constante de Michaelis (Km) são maiores para o extrato dos resíduos do fruto do que para a bromelina pura.
Abstract: The bromelain, enzyme found in pineapple, hydrolyses peptide protein bonds; there is application in several areas involving food, medicine and animal nutrition. In pineapple the bromelain is present in the flesh, skin and core of the fruit. Aiming to evaluate the bromelain present in Brazilian fruit Ananas comosus L. Merril, pérola type, focusing its use from industrialization residues recovering, it was searched, comparing with pure bromelain, pH conditions and temperature for higher activity, thermal stability along the time under several temperatures and the kinetics of its catalytic activity, using casein as a substrate. The extract was obtained crushing the skin and core of the fruit and the hydrolysis reaction, with controlled pH, done in a 75 mL net volume reactor under constant stirring. After reaction a sample was taken, added to a tube with tri chloroacetic acid and centrifuged, analyzing the supernatant absorbance. Activity and kinetics were expressed as mmol of tyrosine / L.min from absorbance at 280 nm of aromatic amino acids generated by casein hydrolysis. Three enzyme / substrate ratio were employed (weight basis):1 / 25, 1 / 50 and 1 / 125 for star type experimental design assays with central point at 7.0 for pH and at 35 °C for temperature, the results were processed giving the model equation and surface responses, the equations were mathematically treated giving graphics of best activity as a function of temperature; the experimental design results showed similarity between bromelain from fruit residues and pure bromelain taken as reference. The assays for thermal stability were carried out by activity determination for 1 / 25 ratio under temperatures varying from 25 °C and 62 °C during 180 minutes for two pH ranges: that for best activity defined from experimental design (5.5 to 6.5) and between 3.3 to 3.5; the results were treated by the analysis of the graphics of activity as a function of time showing that the order one model is adequate to describe the enzyme thermal inactivation and that it is stronger at pH range of 3.3 to 3.5 with values of frequency factor k0 (minute-1) 2.5 x1032 times bigger for the extract.The assays to determine the kinetics of bromelain catalytic activity on casein were carried out at constant temperature of 35 °C and pH of maximum activity defined by experimental design for each one of the three studied enzyme / substrate ratio; curves were built for the concentration of formed amino acids along the time (from zero to 15 minutes) and the results treated calculating the curves derivative at time zero (initial rate); the Michaelis - Menten model showed to be adequate to describe the casein hydrolysis mechanism of casein by bromelain and the results indicate that the maximum reaction rate (Vmax) values and the Michaelis constant (Km) values are bigger for the fruit residues extract than that for pure bromelain.
Doutorado
Sistemas de Processos Quimicos e Informatica
Doutor em Engenharia Química

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13

Barros, Kleber Vanio Gomes. "Caracterização e purificação da enzima bromelina derivada do curaua (Ananas erectifolius) em sistema bifasico aquoso PEG/fosfato." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/267111.

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Orientador: Elias Basile Tambourgi
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica
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Resumo: O curauá (Ananas erectifolius) é uma planta fibrosa proveniente da Amazônia brasileira, pertencente à família Bromeliaceae e ao gênero Ananas. A bromelina é uma protease de origem vegetal, obtida de diversas espécies da família Bromeliaceae. A bromelina tem utilização bastante difundida em processos industriais nas áreas alimentícia e farmacêutica. Efeitos antiinflamatórios da enzima, como também, o seu uso no tratamento da angina, na indigestão entre outros, estão documentados na literatura científica. Estudos de métodos para purificação de biomoléculas que viabilizem a sua obtenção em larga escala com custo reduzido são importantes áreas de pesquisa na biotecnologia. A extração líquido-líquido através de sistemas bifásicos aquosos (SBA) pode ser usada como técnica de pré-purificação de bioprodutos. Estes sistemas formam duas fases aquosas imiscíveis ou parcialmente miscíveis entre si. Podem ser formados a partir da mistura de dois polímeros ou de um polímero e um sal, a exemplo do sistema PEG (polietilenoglicol)/fosfato de potássio. Foi estudada a enzima bromelina derivada das folhas de ambas as variedades: curauá branco e curauá roxo. Pesquisou-se também a recuperação da enzima por extração líquido-líquido em sistemas de duas fases aquosas PEG/fosfato. Realizou-se ensaios em batelada para a extração e recuperação da enzima, utilizando como indicador o coeficiente de partição. Obteve-se fatores de purificação da enzima bromelina para o sistema fosfato de potássio e polietileno glicol 4000 e 6000, nos pH de 7,0; 8,0 e 9,0 a 25 °C. Estudou-se a partição em três diferentes "tie-lines". Analisou-se a influência do pH e do comprimento das linhas de amarração no coeficiente de partição da enzima. Na purificação da bromelina derivada das folhas do curauá branco, observou-se os melhores resultados no sistema bifásico aquoso PEG 4000/Fosfato em pH 7,0. Observou-se que o sistema PEG 6000/Fosfato em pH 7,0 apresentou os melhores resultados em relação à purificação da enzima bromelina derivada das folhas do curauá roxo.
Abstract: The curauá (Ananas erectifolius) is a fibrous plant from brazilian Amazon, belonging to the Bromeliaceae family and Ananas genus. Bromelain is a protease from vegetable origin, obtained from several species of this family. The bromelain has widespread use in industries process, such as in food and pharmaceutical areas. Antiinflammatory effects enzyme and also it uses in angina treatment, indigestion among others are documented in scientific literature. Methods' studies to purification of biomolecules that allow their achievement in large scale with low cost are important research's areas in biotechnology. The liquid-liquid extraction through aqueous twophase system (ATPS) can be used as technical of pre-purification of bioproduct. These systems form aqueous two-phase immiscible or partially miscible within themselves. They can be obtained by the addition of two polymers or one polymer and a salt, such as the PEG - poly(ethyleneglycol) - and potassium phosphate salt system. In the present report we characterized the bromelain enzyme that comes from the leaves of white curauá and purple curauá, and also investigated the recuperation of the enzyme by liquid-liquid extraction in aqueous two-phases PEG-phosphate systems (ATPS). The assays to extraction and recovery of the enzyme were carried out in batch mode, using the partition coefficient as indicator. Getting to factors purification of the enzyme bromelin to PEG 4000 and 6000 and potassium phosphate salt in ATPS, at pH 7.0, 8.0 and 9.0 at 25 ºC. We studied the partition through three different tie-lines. The influences of pH and tie-line length in partition coefficient of enzyme were analyzed. In the purification of bromelain derived from the leaves of white curauá, we observed the best results in PEG 4000/phosphate ATPS at pH 7.0. Furthermore, the system PEG 6000/phosphate at pH 7.0 showed the best results in relation to the purification of the enzyme bromelain derived from the leaves of purple curauá.
Mestrado
Sistemas de Processos Quimicos e Informatica
Mestre em Engenharia Química

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14

Sbruzzi, Dalva. "Análise da viabilidade econômica da purificação da bromelina das folhas de curauá em sistema bifásico aquoso PEG/Fosfato." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266969.

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Анотація:

Orientador: Elias Basile Tambourgi
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química
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Resumo: O curauá (Ananas Erectifolius L.B. Smith), espécie vegetal de porte herbáceo, é uma monocotiledônea pertencente à família Bromeliaceae, nativa da região norte do Brasil, especialmente da Amazônia, de onde pode ser extraída a bromelina. Essa faz parte de um grupo de enzimas proteolíticas, usadas na indústria alimentícia e como medicamento, pois oferece amplo espectro de eficácias terapêuticas: antiedemas, anti-inflamatórias, antitrombóticas e atividades fibrinolíticas. O desenvolvimento de novos processos de extração e purificação de proteínas é muito importante, uma vez que essa é uma etapa limitante na produção de bioprodutos. Sistemas de duas fases aquosas são amplamente utilizados para a separação e purificação de biomoléculas. As vantagens da extração em duas fases aquosas, em comparação com outros métodos de purificação, são o elevado rendimento, a faixa de trabalho próxima do equilíbrio, a fácil ampliação de escala e o uso em processos contínuos. Esta pesquisa propõe a caracterização da bromelina do curauá e a sua purificação por extração líquido-líquido em duas fases aquosas, formadas por um polímero (polietilenoglicol) e um sal (fosfato de potássio). Apresenta também um estudo sobre os custos do processo e o preço de venda estimado, e demonstra a sua viabilidade econômica, quer seja para uso como pré-processo nos tradicionais sistemas cromatográficos, quer para a comercialização direta, como alternativa para a bromelina do abacaxi. Os resultados da caracterização mostraram que as condições ideais de trabalho são pH 8,5 e temperatura 35º C para a variedade branca, e pH 8,5 e 30º C de temperatura para a variedade roxa. A massa molar é de 24 kDa, e o melhor sistema de partição da bromelina foi o SBA PEG 4000 em pH 9. A solução enzimática dos melhores sistemas contém 7 U de bromelina e, aproximadamente, 17 mg/L de proteína total medida por Bradford (curauá branco); e 6 U de bromelina e, aproximadamente, 23 mg/L de proteína total medida por Bradford (curauá roxo). O preço de venda calculado para um litro dessa solução enzimática, quando não se obtém lucro (margem de lucro desejada é 0%), foi estimado em R$75,06. Assim, pode-se concluir que o processo de purificação da bromelina das folhas de curauá, ao ser utilizado sistema bifásico aquoso, PEG/sal, é promissor no que diz respeito a sua possibilidade de produção em escala industrial
Abstract: Curaua (Ananas erectifolius L.B. Smith) is a mocotyledonous herbaceous specie belonging to the Bromeliaceae family and it is native to the north region of Brazil, especially the Amazonian Complex, that we can extract bromelain which belongs to a group of proteolytic enzymes derived from herbaceous species of Bromeliaceae family, which are used in food industries and as drugs as such as they offer a wide spectrum of therapeutic efficacies: antiedemateous, antiinflammatory, antithrombotic and fibrinolytic activities. The development of new extraction and purification processes of proteins is very important, as this is a limiting step in the production of bioproducts. Aqueous two-phase systems are widely used for separation and purification of biomolecules. The advantages of aqueous two-phase extraction compared to other purification methods lie in high productivity, working range close to equilibrium, easy scale up and use in continuous processes. This research proposes the curaua's bromelain characterization, and its purification by a liquid-liquid extraction in aqueous two-phase system, formed by a polymer (polyethylene glycol) and a salt (potassium phosphate). It also presents a study about the costs of this process and the estimated sale price, showing its economic viability, whether it is for use as a pre-process in traditional chromatographic systems or direct commercialization, as an alternative for the bromelain of pineapple. The curaua's bromelain characterization results showed that the ideal working conditions are pH 8.5 and 35 ºC of temperature to white variety and pH 8.5 and 30°C of temperature to purple variety. The curaua's molecular weight is 24 kDa and the best bromelain partitioning system was the SBA PEG 4000 at pH 9. The enzyme solution of the best purification system contains 7 U of bromelain and about 17 mg/L of total protein measured by Bradford (white curaua) and 6 U of bromelain and about 23 mg/L of total protein measured by Bradford (purple curaua). The estimated sale price for a liter of this enzyme solution, when profit is not achieved (0% of desired markup), was estimated at R$ 75, 06. So, the curaua's bromelain purification process using an aqueous two-phase system, PEG/salt, is promising with regard to the possibility of industrial scale production
Mestrado
Sistemas de Processos Quimicos e Informatica
Mestre em Engenharia Química

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15

Mekaoui, Nazim. "Contribution à l'étude de la chromatographie à contre-courant : partage de composés ionisables, nouvelles colonnes et purification séquentielles." Thesis, Lyon 1, 2012. http://www.theses.fr/2012LYO10249/document.

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La chromatographie à contre courant (CCC) est une technique de purification chimique préparative quitravaille avec un système biphasique liquide. Une phase est la phase mobile, l'autre phase est la phasestationnaire. Il n'y a aucun support solide: un champ de force centrifuge est utilisé pour maintenir en place laphase stationnaire. Ce travail est une contribution à l'étude de la purification préparative par CCC. Après uneimportante étude bibliographique des procédés de purification en continu tant en CCC qu'autres, il est montréque la méthode dite "multi-dual-mode", ou MDM, est une solution possible. Elle consiste à utiliser le fait queles deux phases liquides peuvent servir de phase stationnaire: il suffit d'inverser le sens de circulation et lanature de la phase mobile (méthode dual-mode). Le mélange est séparé de façon classique pendant untemps chronométré, puis on inverse le rôle des phases: la phase mobile devient stationnaire et vice versa eton inverse également le sens de circulation (ascendant devient descendant ou vice versa). On sort lescomposants du mélange soit d'un coté de la colonne CCC, soit de l'autre. La méthode est mise en oeuvrepour purifier le Bleu de Coomassie en le débarassant des ses composés polaires (d'un coté) et apolaire (del'autre coté de la colonne et en accumulant dans la colonne la fraction de polarité intermédiaire, fractiond'intérêt. Une nouvelle colonne hydrostatique de petit volume (30 mL) a également été testée: elle permetde tester un nouveau système liquide très rapidement
Counter-current chromatography (CCC) is a preparative purification technique that works with the twoliquid phases of a biphasic liquid system. One phase is used as the mobile phase when the other phase isused as the stationary phase. There is no solid support: centrifugal fields are used to obtain a support-freeliquid stationary phase. This work contains an exhaustive bibliographic study of what can be found in theliterature concerning continuous chromatographic processes. The multi-dual-mode (MDM) process was foundto be the best one able to purify large amount of crude mixtures. The MDM method starts with a classicalseparation of the mixture followed by a switch of both the liquid phase nature and the flowing direction. Themobile phase flowing e.g. in a descending direction becomes the stationary phase. The previous stationaryphase becomes the mobile phase flowing in the ascending direction (or vice versa). The purified compoundsof the introduced mixture are eluted at one side of the column or the other according to their polarity. TheMDM method was used to purify a crude sample of Coomassie Blue: the polar part of the dye was eluted atthe column top (or head) and the apolar part at the column bottom (or tail) while the essential part of the dyewas trapped inside the CCC column. The work also presents a new small volume (30 mL) hydrostatic CCCcolumn. It is shown that this column could be used to test quickly the potential of a given biphasic liquidsystem

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Ferreira, Juliana Ferrari. "Caracterização e purificação da enzima bromelina em sistema de duas fases aquosas PEG/Fosfato." [s.n.], 2007. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266254.

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Анотація:

Orientador: Elias Basile Tambourgi
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica
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Resumo: A bromelina é uma protease de origem vegetal, obtida de diversas espécies da família Bromeliaceae, que está presente no talo e no fruto do abacaxi. O uso da bromelina é baseado em sua atividade proteolítica nas indústrias alimentícias e principalmente na farmacêutica brasileira. A bromelina é muito bem documentada pelos seus efeitos curativos em todas as condições inflamatórias, além de ter sua eficácia provada na cura de vários outros problemas de saúde, tais como: angina, indigestão e problemas respiratórios. Vários métodos de purificação da bromelina estão em estudo, sobretudo da bromelina do talo. A extração líquido-líquido é aplicada há muitos anos como uma valiosa técnica laboratorial de separação. Esta pode ser usada como um passo da pré-purificação usando um sistema de duas fases aquosas. Esses sistemas foram testados com sucesso, são sistemas formados por duas fases aquosas imiscíveis ou parcialmente miscíveis entre si, obtidas pela mistura de polímeros hidrofílicos ou um desses polímeros e um sal, como o sistema PEG (polietileno glicol) e o fosfato de potássio. O presente trabalho estudou a caracterização da enzima e a recuperação da bromelina presente na casca e talo do abacaxi, por extração líquido-líquido em sistemas de duas fases aquosas PEG/ fosfato. Realizou-se ensaios em batelada para a extração e recuperação da enzima, utilizando como indicador o coeficiente de partição. Obtiveram-se diagramas de fases para o sistema fosfato de potássio e polietileno glicol 1500 e 4000 nos pH¿s de 6 a 11, a 25 °C. Estudou-se três diferentes ¿tie-lines¿. Analisou-se a influência do pH e do comprimento das ¿tie-lines¿ no coeficiente de partição da enzima
Abstract: The bromelains are proteases from vegetable origin, obtained from several species of Bromeliaceae family, which are found in pineapple¿s stem and fruit. The bromelains uses are based on its proteolytic activity on food industries and mostly at Brazilian pharmaceutical industry. The bromelains has been documented by its therapeutic effects at all inflammatory conditions, in addition to its attested efficiency of cure of various health problems, such as angina, indigestion and respiratory problems. Various bromelains¿ purification methods has been studied, particularly of stem¿s bromelain. Aqueous two-phase systems has been applied for several years as a good laboratorial separation technique and they can be used as a prepurification step. These systems have been tested with large success. The systems are formed by two aqueous phases immiscible or partially miscible within themselves, obtained by the addition of hydrophilic polymers or one hydrophilic polymer and a salt, such as the poly(ethylene glycol) ¿ PEG ¿ and potassium phosphate salt systems. This work studied the enzyme characterization and recuperation presented in the pineapple¿s stem and skin, by aqueous two-phase systems liquid-liquid extraction. Batch assays were performed aiming the enzyme extraction and recuperation, using the partition coefficient as indicator. The phase diagrams from PEG and potassium phosphate salts aqueous two-phase systems were obtained for PEG molecular weight of 1500 and 4000 at pH 6.0 to 11.0, at 25 ºC. Three different tie-lines were also studied. The pH and tieline length influence on the enzyme partition coefficient were analysed.
Mestrado
Sistemas de Processos Quimicos e Informatica
Mestre em Engenharia Química

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17

Diemer, Étienne. "Intensification du procédé d’extraction, de purification et de fonctionnalisation des acides caféoylquiniques à partir de coproduits de la culture de l’endive." Electronic Thesis or Diss., Compiègne, 2024. http://www.theses.fr/2024COMP2821.

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La racine forcée d’endive est un coproduit de la culture de l’endive, produit caractéristique du Nord de la France, de la Belgique et des Pays-Bas. Actuellement sous utilisé en méthanisation ou en alimentation animale, ce coproduit contient pourtant des molécules d’intérêts à haute valeur ajoutée : les acides caféoylquiniques. Ces molécules possèdent des activités antioxydantes, anti-inflammatoires et permettent de limiter les maladies du désordre métabolique. Ce travail de thèse vise à intensifier le prétraitement, l’extraction, la purification et la fonctionnalisation des acides caféoylquiniques à partir des racines forcées pour développer de nouvelles molécules bioactives biosourcées potentiellement intéressantes pour le secteur cosmétique et nutraceutique. Une dernière partie de la thèse porte sur l’étude technico-économique du procédé pour estimer sa rentabilité économique en fonction du secteur d’application visé. La première partie porte sur l’effet des prétraitements conventionnels (découpe et séchage) ainsi que l’effet d’un prétraitement électrique par champs électriques pulsés sur les teneurs en acides caféoylquiniques dans la biomasse. L’effet de l’ajout d’une solution antioxydante lors de l’extraction est également étudié. Dans un deuxième temps, une optimisation de l’extraction est réalisée à partir de biomasse sèche et fraiche. L’influence de facteurs tels que la température, le ratio solide/liquide, ainsi que la nature du solvant a été étudiée. De plus, des cinétiques d’extraction ont été tracées pour étudier les paramètres cinétiques à l’aide d’un modèle empirique. La pureté de l’extrait obtenu étant faible, des étapes de purification sont donc nécessaires. Par la suite, les travaux se sont portés sur la purification de l’extrait brut à l’aide de résines macroporeuses ainsi que par extraction liquide/liquide. Pour la purification par résine, un screening de résines est réalisé suivi d’une optimisation des conditions opératoires de purification avec la résine choisie. Des modélisations des phénomènes d’adsorption sont réalisées pour déterminer les étapes limitantes ainsi que la capacité maximale d’adsorption. Pour l’extraction liquide/liquide, un screening de solvants verts est effectué à partir d’un milieu aqueux et hydro-éthanolique puis une optimisation des conditions opératoires avec le meilleur solvant est réalisée. La pénultième partie de la thèse cherche à fonctionnaliser par estérification les acides caféoylquiniques à partir d’une solution modèle puis d’un extrait réel. Les conditions d’estérification sont optimisées pour augmenter la vitesse de réaction ainsi que le taux de conversion. Des esters avec différentes longueurs de chaine sont obtenus et l’activité antioxydante ainsi que les propriétés anti-UV sont étudiées. La fonctionnalisation est par la suite effectuée sur un extrait réel. Une étude technico-économique conclut la thèse permettant d’ouvrir sur des perspectives quant aux conditions nécessaires à l’industrialisation du procédé de valorisation des racines forcées d’endive
Forced chicory root is a by-product of Belgian endive culture, a typical crop of northern France, Belgium and the Netherlands. Currently under-utilized in methanation or animal feed, this by-product contains molecules of interest: caffeoylquinic acids. These molecules have antioxidant and anti-inflammatory properties, and a potential for reducing metabolic disorders. This thesis aims to intensify the pre-treatment, extraction, purification and functionalization of caffeoylquinic acids from forced chicory roots to develop new bioactive biosourced molecules of potential interest to the cosmetics and nutraceutical sectors. The final part of the thesis deals with a technico-economical study of the process to estimate its economic profitability in relation to the targeted application sector. The first part focuses on the effect of conventional pretreatments (cutting and drying) and the effect of pulsed electric field pretreatment on caffeoylquinic acid content in biomass. The effect of adding an antioxidant solution during extraction is also investigated. Secondly, extraction optimization is carried out using dry or fresh biomass. The influence of factors such as temperature, solid/liquid ratio and solvent type were studied. In addition, extraction kinetics were performed to study kinetic parameters using empirical models. As the purity of the extract obtained is low, purification steps are needed. The thesis then focused on purifying the crude extract obtained using macroporous resins and liquid/liquid extraction. For resin purification, resin screening was carried out, followed by optimization of the purification operating conditions with the chosen resin. Models of adsorption phenomena are carried out to identify the limiting stages and the maximum adsorption capacity. For liquid/liquid extraction, green solvent screening is carried out on aqueous and hydro-ethanolic media, followed by optimization of operating conditions with the best solvent. The penultimate part of the thesis seeks to functionalize caffeoylquinic acids by esterification, starting with a model solution and then a real extract. Esterification conditions are optimized to increase both reaction speed and conversion rate. Esters with different chain lengths were obtained, and biological activities such as antioxidant activity and anti-UV properties were studied. Functionalization is also performed with real extract. A technico-economic study concludes the thesis, opening up prospects for the industrialization of the forced chicory roots valorization process

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Solastiouk, Pierre. "Application de l'extraction liquide-liquide au traitement et a la revalorisation d'effluents industriels." Université Louis Pasteur (Strasbourg) (1971-2008), 1986. http://www.theses.fr/1986STR13140.

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Proposition d'une nouvelle approche de l'elimination des effluents des ateliers de traitement de surface. Separation zinc/nickel en solution concentree et separation du chrome hexavalent dans des effluents chromates

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19

Haddou, Boumediene. "Purification d'effluents par extraction à deux phases aqueuses." Toulouse, INPT, 2003. http://www.theses.fr/2003INPT009G.

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La plupart des composés hydrophobes présents dans une solution aqueuse, peuvent être solubilisés dans les micelles d'un tensioactif non ionique, puis concentrés dans le petit volume du coacervat, après séparation des phases. Dans ce travail, afin d'étudier l'extraction du phénol ou de l'alcool benzylique (soluté) de leurs solutions aqueuses (pollution soluble), nous avons choisi de travailler avec des alcools plyéthoxylés aisément et rapidement biodégradables. Les résultats expérimentaux d'extraction du phénol ou d'alcool benzylique en solution aqueuse à 0. 15% massique, sont exprimés par les quatre grandeurs suivantes : pourcentage de phénol soluté, concentrations résiduelles en soluté et en tensio-actif dans la phase diluée, fraction volumique de coacervat à l'équilibre. Le procédé dérivé de l'extraction à deux phases aqueuses, consiste en l'élimination d'une pollution dispersée par désémulsification. Le cas des boues polluées par des huiles de coupe utilisées dans le sciage, le taillage et le pollissage du granit en fournit un excellent exemple.

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Esteves, Pedro Duarte de Oliveira. "Extraction and purification of theobromine using ionic liquids." Master's thesis, Universidade de Aveiro, 2015. http://hdl.handle.net/10773/16056.

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Mestrado em Bioquímica - Bioquímica Clínica
Theobromine is an alkaloid present in cocoa and it is used in the treatment of atherosclerosis, hypertension, angina, among others. Due to its importance, the aim of this work consists on the development of an efficient and sustainable technology for the extraction of theobromine from cocoa beans. For the development of a purification technique for theobromine extracted from cocoa, aqueous biphasic systems (ABS) composed of ionic liquids (ILs) were initially studied to infer on the most promising systems. Cholinium-based ILs, based on a non-toxic and biocompatible cation, were used combined with two polymers (PPG 400 and PEG 400) and an inorganic salt (K3PO4). The respective phase diagrams at 298 K and atmospheric pressure were determined, as well as their extraction efficiencies for theobromine. The results obtained indicate that K3PO4 has a greater ability to induce the formation of ABS compared to PEG 400 and PPG 400. ABS consisting of K3PO4 also have a high potential for the extraction of theobromine, with extraction efficiencies ranging between 96.4 and 99.9 %. Based on the most promising ILs for the purification step, they were further used in aqueous solution to extract theobromine from cocoa beans, with extraction yields ranging between 4.5% and 6.5 wt%. Finally, ABS were applied to the aqueous solutions containing theobromine from the cocoa extract, with extraction efficiencies ranging between 96.7 and 99.0%.
A teobromina é um alcaloide utilizado no tratamento de aterosclerose, hipertensão, angina, entre outros. Dada a sua importância medicinal, o principal objetivo deste trabalho consistiu no desenvolvimento de uma técnica eficiente e sustentável para extrair teobromina das sementes de cacau. Visando o desenvolvimento de uma técnica de purificação para o extrato obtido a partir do cacau, primeiramente estudaram-se sistemas aquosos bifásicos (SABs) constituídos por líquidos iónicos (LIs) para inferir sobre os sistemas mais promissores. Foram utilizados LIs à base do catião colínio, catião não tóxico e biocompatível, em conjunto com 2 polímeros (PPG 400 e PEG 400) e um sal inorgânico (K3PO4) para a formação de SABs. Determinaram-se os diagramas de fase, à temperatura de 298 K e à pressão atmosférica, assim como as eficiências de extração destes sistemas para a teobromina. Os resultados obtidos indicam que o K3PO4 apresenta uma maior capacidade de induzir a formação de SABs do que o PPG 400 e o PEG 400. Os SABs constituídos por K3PO4 também demonstraram ter um grande potencial para a extração da teobromina, com eficiências de extração entre 96,4 e 99,9 %. Tendo por base os LIs mais promissores para a etapa de purificação, estes foram posteriormente utilizados em solução aquosa para a extração de teobromina a partir das sementes de cacau, tendo sido obtidos valores de extração de teobromina entre 4,5 e 6,5 (m/m) %. Por fim, procedeu-se à utilização de SABs como método de purificação a partir da solução aquosa contendo o extrato, e obtiveram-se valores de eficiências de extração entre 96,7 e 99,0 %.

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Santangelo, Francesca [Verfasser]. "Ionic Liquids as extraction solvents for Biobutanol purification / Francesca Santangelo." München : Verlag Dr. Hut, 2013. http://d-nb.info/1045989274/34.

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22

Haj, Youssef Mouna. "Extraction liquide - liquide et extraction par émulsions appliquées à la purification de l'acide phosphorique vis-à-vis du cadmium." Châtenay-Malabry, Ecole centrale de Paris, 2008. http://www.theses.fr/2008ECAP1108.

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Dans cette thèse nous nous intéressons à la purification de l'acide phophorique par extraction du cadmium. Deux techniques ont été utilisées : l'Extraction liquide liquide et l'Extraction par membrane liquide émulsionnée. Notre apport par rapport à la première technique consiste en l'utilisation d'un nouveau couple extractant-desextractant qui sont respectivement l'acide di (2) éthylheryl dithiophosphorique synthétisé au sein du laboratioire et le (HCl 4M ou HCl 1M+NaCl 3M). Les essais expérimentaux réalisés ont permis de montrer l'efficacité de ce nouveau couple extractant-desextractant et de déduire les mécanisme d'extraction et de désextraction. L'étude de l'Extraction par membrane liquide émulsionnée nous a permis de démontrer expérimentalement que cette technique permet d'extraire la même quantité de cadmium tout en utilisant moins de D2EHDTPA. En optimisant la formulation de l'émulsion, nous avons montré qu'on peut atteindre un facteur de concentration élevé. Ceci signifie qu'on peut concentrer le cadmium dans un volume très réduit de la phase aqueuse de l'émulsion, ce qui est intéressant de point de vue de protection de l'environnement. L'étude de ces deux techniques d'extraction est accompagnée par l'étude des tests de faisabilité de procédés industriels. Le procédé retenu est sous forme d'un étage en mélangeur décanteur. Le pilote proposé en extraction liquide-liquide comporte deux étages d'extraction dont la performance de chacun est de 99% et 6 étages en désextraction. Avec un tel montage on a pu concentrer le cadmium 50 fois et ceci en partant d'une concentration initiale de cadmium égale à 40 mg. L-1.

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Sukhbaatar, Tamir. "Approche multi-échelle pour la compréhension de mécanismes d'extraction de l'uranium en utilisant des liquides ioniques." Thesis, Montpellier, Ecole nationale supérieure de chimie, 2018. http://www.theses.fr/2018ENCM0002.

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En raison de leurs propriétés intéressantes telles que faible tension de vapeur, non-inflammabilité et grande fenêtre électrochimique, les Liquides Ioniques sont considérés comme alternatifs aux solvants organiques volatils et font l’objet d’études dans diverses applications comme par exemple en extraction liquide-liquide qui est l’une des techniques de séparation la plus utilisée en hydrométallurgie. L’influence de ces nouveaux diluants sur les propriétés d’agrégation des molécules extractantes et sur leurs propriétés extractantes n’a jusqu’à aujourd’hui pas été appréhendée de façon générale, et encore moins, quant à l’extraction de l’uranium d’un lixiviat acide. Les travaux de cette thèse se focalisent donc sur l’étude de l’effet de l’agrégation des extractants usuels (mélange synergique HDEHP/TOPO et trioctylamine respectivement) et des nouveaux composés bifonctionnels issus des familles amidophosphonates et oxyde d’aminophosphines sur l’extraction de l’uranium i) des milieux phosphates et ii) des milieux sulfates. Les propriétés extractantes ont pour la première fois été comparées à leurs propriétés d’agrégation dans un liquide ionique sélectionné, par des mesures de diffusion des rayons X et des neutrons aux petits angles. Ces données en complément des mesures de tension de surface ont permis de déterminer pour chaque système, la Concentration d’Agrégation Critique, analogue de la Concentration de Micellisation Critique pour les tensioactifs, qui est reliée à l’énergie libre de micellisation. Les mécanismes d’extraction ainsi que la nature des espèces extraites ont également été recherchés afin de comparer les résultats du milieu liquide ionique à ceux du milieu classique
Due to their attractive properties such as negligible vapor pressure, non-flammability and large electrochemical window, Ionic Liquids are considered to be good substitutes to volatile organic compounds and have been main topic of many research studies for different applications including solvent extraction, which is one of the widely used techniques in hydrometallurgy. Despite a large number of reported mechanistic studies, effect of such diluents on both of extracting agents’ capacity and self-assembling feature has not been elucidated so far and even less concerning uranium extraction from a leachate produced by ore leaching. In this context, main focus of the present thesis has been uranium extraction from i) phosphate media and ii) sulfate media by using ionic liquid as a diluent of an extracting phase. First of all, a screening test of different ionic liquids has been performed with the reference extracting agents (HDEHP/TOPO mixture for extraction from phosphate media and trioctylamine from sulfate media) as well as with amidophosphonate and aminophosphine oxide bifunctional compounds. Then, uranium extraction mechanisms in a selected ionic liquid with these extractants have been investigated at molecular and supramolecular scales. As an analogy to the Critical Micellar Concentration which is related to the Gibbs free energy of Micellization in a case of surfactants, a Critical Aggregation Concentration has been determined by using results obtained by Small-Angle X ray, Neutron Scattering techniques and interfacial tension measurements. Finally, the results obtained in the ionic liquid have been compared to those obtained in a conventional molecular diluent

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Vadon, Mathieu. "Extraction de bore par oxydation du silicium liquide pour applications photovoltaïques." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAI067/document.

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L'extraction du bore du silicium liquide est une étape d'une chaîne de procédés de purification de silicium de qualité suffisante pour les applications photovoltaïques. Cette thèse étudie en priorité le procédé dit "gaz froid" qui consiste en l'injection d'un mélange de gaz Ar-H2-H2O sur du silicium liquide chauffé électromagnétiquement. Une deuxième méthode similaire ("procédé plasma") où on injecte un plasma thermique issu d'un mélange Ar-H2-O2 a également été étudiée. Un modèle est nécessaire afin d'optimiser le procédé pour économiser de l'énergie.Les trois objectifs du modèle sont la prédiction du flux de silicium issu de la surface (vitesse d'oxydation), du flux de bore issu de la surface (pour avoir la vitesse de purification), et du seuil de passivation. Le seuil de passivation est la limite de concentration d'oxydant au-delà de laquelleil apparait une couche de silice passivante qui empêche la purification. Afin de minimiser la consommation d'énergie en accélérant le procédé, on cherche à injecter une concentration d'oxydant juste en dessous du seuil de passivation.De précédentes études ont montré que le facteur limitant pour les flux de bore et de silicium est le transport d'oxydant dans la phase gaz. Ainsi, nous avons fait un modèle monodimensionnel réactif-diffusif à l'équilibre thermodynamique de la couche limite gazeuse. Selon ce modèle, l'effet de la formation d'aérosols de silice est de diviser par deux le flux d'oxydant vers la surface, ce qui sert aux simulations CFD. Cet effet des aérosols de silice sur les flux d'oxydant peut aussi se retrouver si on enlève l'hypothèse d'équilibre thermodynamique des aérosols de silice avec la phase gaz, ce qui est confirmé par des simulations CFD et des expériences.Pour ce qui concerne l'estimation de la vitesse de purification, les données les plus réalistes concernant l'enthalpie de formation de HBO(g) et le coefficient d'activité du bore dans le silicium liquide ont été sélectionnées. Nous obtenons une bonne prédiction de la vitesse de purification à différentes températures et concentrations d'oxydant, y compris pour le cas plasma que nous avons étudié, en utilisant ces données thermodynamiques et en supposant que les produits de réaction de surface SiO(g) et HBO(g) diffusent de manière similaire. Ces coefficients de transfert identiques pour HBO(g) et SiO(g) peuvent s'expliquer par une précipitation simultanée et commune de HBO(g) et SiO(g), selon des mécanismes de germination et croissance restant à déterminer.Un dispositif expérimental de lévitation électromagnétique de silicium sous un jet oxydant a été monté. La mesure et le contrôle de température d'une bille de silicium ont été mis en oeuvre ce qui permettra la mesure sans contaminations de données thermodynamiques concernant les impuretés .Le seuil de passivation mesuré sur quelques expériences disponibles peut être prédit par notre modèle d'oxydation (associé au facteur deux représentant les aérosols de silice), si on l'associe à un critère proposé dans la littérature, qui couple la fraction du flux d'oxydant arrivant à la surface à une loi d'équilibre entre SiO(g), Si(l) et SiO2(s/l). Nous montrons dans cette thèse que la couche passivante n'est compatible avec des aérosols de silice que si ces aérosols ne sont pas en équilibre avec la phase gaz. La cinétique de formation des aérosols de silice doit donc être étudiée plus en détails
Boron extraction from liquid silicon is a step within a new chain of processes aimed to purify silicon that meets purity requirements specific to photovoltaic applications. This thesis focuses mostly on cold gas processes that involve the injection of a mixture of Ar-H2-H2O gases onto electromagnetically stirred liquid silicon. A second similar method ("plasma processes") that involves the injection of thermal plasma made from an Ar-H2-H2O mixture has also been studied. A model is needed to minimize energy consumption by optimizing the process.We want to be able to predict the flow of silicon from the reactive surface (oxidation speed), the flow of boron from the surface (to have the purification speed) and the passivation threshold. For a given setting, the passivation threshold is the limit oxydant partial pressure at injection beyond which a passivating silica layer appears on the surface of the liquid silicon, which interrupts the purification. In order to minimize the energy consumption, and for that matter , in order to speed up the process, we want to inject oxydant in a quantity just below the passivation threshold.Previous studies have shown that the limiting factor for the oxidation and purification speed is the transport of oxidant in the gas phase. That's why we have made a 1D reactive-diffusive model at thermodynamical equilibrium of the gaseous boundary layer. According to this model the effect of the formation of silica aerosols is to divide by two the flow of oxydant towards the surface, which is useful for the simplification of CFD simulations. This effect of the formation of silica aerosols on oxidant flows can also be found without the hypothesis of thermodynamical equilibrium of silica aerosols with the gas phase, as confirmed by simulations and experiments.Regarding the estimation of the purification speed, we have selected the most realistic values of the enthalpy of formation of HBO(g) and of the activity coefficient of boron in liquid silicon.We could get good estimates of the purification speed at different temperatures and levels of oxidant concentrations at injection, by using the selected thermodynamical values and by supposing that the surface reaction products HBO(g) and SiO(g) diffuse similarly. A reason for this similar diffusion of SiO(g) and HBO(g) might be a common and simultaneous precipitation , due to specific dynamics of nucleation and growth that need to be investigated further. Those results for cold gas processed could also be obtained for a plasma experiment.However for the plasma experiment, silica aerosols can be formed only in a very thin layer near the surface and this result needs confirmation from other experiments.Temperature measurement and control for electromagnetically levitating liquid silicon under a flow of oxidant were achieved. With more time, quantitative results could be achieved to measure thermodynamical data on impurities without contaminations.Regarding the prediction of the passivation threshold, we justified a thermodynamical equilibrium at surface of SiO(g) with Si(l) and SiO2(s/l) at passivation threshold with the spreading of silica particles over the liquid silicon surface with the stirring. We show that the passivation layer is compatible with silica aerosols only if those aerosols are not in equilibrium with the gas phase. Therefore the kinetics of formation of silica aerosols should be studied further. A previous empirical formula on the prediction of the passivation threshold for experiments where H2O is the oxidant has been confirmed using our CFD model. A passivation experiment has shown the absence of impact of silica aerosols on oxidant transport when the oxidant is O2

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Faustino, Vânia Filipa Martins. "Extraction and purification of immunoglobulin G with aqueous biphasic systems." Master's thesis, Universidade de Aveiro, 2015. http://hdl.handle.net/10773/16144.

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Mestrado em Biotecnologia - Biotecnologia Industrial e Ambiental
The immune system is able to produce antibodies, which have the capacity to recognize and to bind to foreign molecules or pathogenic organisms. Currently, there are a diversity of diseases that can be treated with antibodies, like immunoglobulins G (IgG). Thereby, the development of cost-efficient processes for their extraction and purification is an area of main interest in biotechnology. Aqueous biphasic systems (ABS) have been investigated for this purpose, once they allow the reduction of costs and the number of steps involved in the process, when compared with conventional methods. Nevertheless, typical ABS have not showed to be selective, resulting in low purification factors and yields. In this context, the addition of ionic liquids (ILs) as adjuvants can be a viable and potential alternative to tailor the selectivity of these systems. In this work, ABS composed of polyethylene glycol (PEG) of different molecular weight, and a biodegradable salt (potassium citrate) using ILs as adjuvants (5 wt%), were studied for the extraction and purification of IgG from a rabbit source. Initially, it was tested the extraction time, the effect on the molecular weight of PEG in a buffer solution of K3C6H5O7/C6H8O7 at pH≈7, and the effect of pH (59) on the yield (YIgG) and extraction efficiency (EEIgG%) of IgG. The best results regarding EEIgG% were achieved with a centrifugation step at 1000 rpm, during 10 min, in order to promote the separation of phases followed by 120 min of equilibrium. This procedure was then applied to the remaining experiments. The results obtained in the study of PEGs with different molecular weights, revealed a high affinity of IgG for the PEG-rich phase, and particularly for PEGs of lower molecular weight (EEIgG% of 96 % with PEG 400). On the other hand, the variation of pH in the buffer solution did not show a significant effect on the EEIgG%. Finally, it was evaluated the influence of the addition of different ILs (5% wt) on the IgG extraction in ABS composed of PEG 400 at pH≈7. In these studies, it was possible to obtain EEIgG% of 100% with the ILs composed of the anions [TOS]-, [CH3CO2]-and Cl-, although the obtained YIgG% were lower than 40%. On the other hand, the ILs composed of the anions Br-, as well as of the cation [C10mim]+, although not leading to EEIgG% of 100%, provide an increase in the YIgG%. ABS composed of PEG, a biodegradable organic salt and ILs as adjuvants, revealed to be an alternative and promising method to purify IgG. However, additional studies are still required in order to reduce the loss of IgG.
O sistema imunitário tem como ferramenta mais poderosa a produção de anticorpos, pois estes têm a capacidade de reconhecer e ligar-se a moléculas/organismos patogénicos. Atualmente, existem uma série de doenças que podem ser tratadas com anticorpos, nomeadamente com as imunoglobulinas G (IgG). Assim, o desenvolvimento de processos mais baratos e eficazes para a sua extração e purificação é uma área de interesse em biotecnologia. Os sistemas aquosos bifásicos (SAB) têm sido estudados para o efeito pois permitem a redução de custos e do número de passos envolvidos no processo, em comparação com os métodos convencionais. No entanto, os SAB tradicionais têm-se mostrado pouco seletivos, resultando em baixos fatores de purificação e rendimentos. Neste sentido, a incorporação de líquidos iónicos (LIs) nos SAB pode ser uma alternativa promissora para manipular a seletividade destes sistemas. Neste trabalho, estudaram-se SAB constituídos por polietileno glicol (PEG) de diferentes massas moleculares e um sal biodegradável (citrato de potássio), utilizando LIs como adjuvantes (5% m/m) para a extração de IgG de origem leporídea (coelho). Inicialmente, estudaram-se o tempo de extração, o efeito da variação da massa molecular do PEG em solução tampão de K3C6H5O7/C6H8O7 a pH≈7 e o efeito da variação de pH (5-9) sobre o rendimento (YIgG) e eficiência de extração (EEIgG%) de IgG. Os melhores resultados obtidos em termos de EEIgG% foram conseguidos com uma centrifugação a 1000 rpm durante 10 min para promover a separação de fases e equílibrio seguidos de 120 min de repouso. Este procedimento foi posteriormente aplicado aos restantes ensaios experimentais. Os resultados obtidos no estudo de PEGs de diferentes pesos moleculares revelaram uma elevada afinidade da IgG para a fase de PEG, principalmente com os PEGs de menor peso molecular (96% de EEIgG% com o PEG 400). Por outro lado, a variação de pH da solução tampão não mostrou um efeito significativo sobre a EEIgG%. Por fim, foi avaliada a influência da adição de vários LIs (5% m/m) na extração de IgG nos SABs compostos por PEG 400 a pH≈7. Nestes estudos foi possível obter uma EEIgG% de 100% com os LIs constituídos pelos aniões [TOS]-, [CH3CO2]- e Cl-, apesar dos YIgG% obtidos serem inferiores a 40%. Por outro lado, com LIs constituídos pelos aniões Br-, assim como pelos catião [C10mim]+, não se conseguiram obter valores de 100% para a EEIgG%, mas obtiveram-se melhores resultados em termos de YIgG%. Os SAB constituídos por PEG, um sal orgânico biodegradável e LIs como adjuvantes revelaram-se um método alternativo e promissor para a purificação de IgG. No entanto, são necessários ainda estudos adicionais de modo a reduzir a perda de IgG durante o processo.

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26

Nait-Si, Youssef. "Extraction, purification, comportement chimique de l'hypéricine et de la pseudohypéricine du millepertuis (hypericum perforatum)." Aix-Marseille 3, 2002. http://www.theses.fr/2002AIX30073.

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Le millepertuis est une plante médicinale à activités multiples qui contient deux caractéristiques, l'hypéricine et la pseudohypéricine, aux quelles on a attribué certaines de ces activités. Ce travail a eu pour objet la mise au point de procédés permettant d'obtenir les deux naphthodianthrones pures. Un critère de pureté des deux composés a d'abord été élaboré. Ensuite des protocoles d'extraction de la plante et de purification ont été mis au point jusqu'à l'obtention d'un extrait enrichi en hypéricine et pseudohypéricine. Les deux composés sont ensuite séparés par deux chromatographies successives sur silice et silice greffée et obtenus purs par précipitation. L'étude de leur comportement a montré que l'hypéricine est stable en milieu hydraté alors que la pseudohypéricine est transformée en isopseudohypéricine, nouvelle naphthodianthrone. Nous avons mis en évidence un équilibre entre la pseudo et isopseudohypéricine en milieu hydraté neutre et le déplacement total de l'équilibre vers l'isopseudohypéricine en milieu faiblement alcalin et vers la pseudohypéricine en milieu faiblement acide
St. -John's-wort (Hypericum perferatum) is a medical plant with multiple activities which contains two characteristic compounds, hypericin and the pseudohypericin, in wich one attributed some of these activities. This work had for object the settling of processes allowing to obtain the two naphthdianthrons at an high degree of purity. Firstly a criterion of purity of the two compound was elaborated. Subsequently, protocols for extracting the plant and purifying extracts were finalized for obtaining an extract enriched in hypericin and pseudohypericin. The compounds are then separated by two successive chromatographies using silica gel and silica gel C-18 reversed phase and obtained pure up to 95 % by precipitation. The study of their behavior showed that the hypericin is stable in hydrated medium while the pseudohypericin is transformed into isopseudohypericin, a new naphthodianthron. We shown an equilibrum between pseudo and isopseudohypericin in neutral hydrated medium and the a full deplacement of the equilibrum to isopseudohypericin in weakly alkaline medium and to pseudohypericin in weakly acid one

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QUEIROZ, CARLOS A. da S. "Terras raras: fracionamento, purificação e controle analítico." reponame:Repositório Institucional do IPEN, 1988. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11634.

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Made available in DSpace on 2014-10-09T12:54:09Z (GMT). No. of bitstreams: 0
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Dissertacao (Mestrado)
IEA/D
Instituto de Quimica, Universidade de Sao Paulo - IQ/USP

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Sá, Fernando Luís de Góis Rodrigues de. "Separation and purification of microbial bioplastics." Master's thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/22681.

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Mestrado em Biotecnologia - Biotecnologia Industrial e Ambiental
Os polihidroxialcanoatos são poliésteres biodegradáveis produzidos por inúmeros organismos. Possuem características muito semelhantes às dos plásticos, apresentando-se como um possível substituto dos mesmos. Os PHAs são produzidos na forma de corpos de inclusão, sendo necessária a sua extração. Os surfactantes são compostos tensioativos capazes de extrair os PHAs, através da sua incorporação, e consequente saturação, nas membranas bacterianas, auxiliando na sua lise. Neste trabalho começou-se por testar a eficácia de uma variedade de surfactantes, e alguns líquidos iónicos, na extração de PHA de culturas mistas. O Tween 20 destacou-se dos restantes visto praticamente não apresentar acumulação de surfactante na amostra de PHA, tendo igualmente sido responsável pelo isolamento e análise do mesmo, de forma eficiente. Com este composto realizaram-se testes onde se variaram a quantidade de biomassa, a concentração de surfactante e o tempo de digestão. Quanto às concentrações de surfactante utilizadas, 50mM, 150mM, 250mM, 400mM e 500mM, os melhores rendimentos de extração (56-61%) foram conseguidos com menores concentrações de surfactante (50mM e 150mM). Com os tempos de digestão (2h, 4h, 6h, 8h e 14h) e com a quantidade de biomassa (0.3g e 0.8g), verificou-se que com quantidades e tempos mais reduzidos (4h e 0.3g) foi possível obter melhores ou semelhantes resultados aos obtidos com valores superiores de tempo e biomassa. O clorofórmio foi substituído pelo dimetil carbonato no passo de purificação, reduzindo bastante a toxicidade do processo. Foi também elaborada uma extração utilizando apenas digestão com surfactante, sem purificação, atingindo-se um rendimento de 16.17%. Para além dos semelhantes resultados obtidos neste trabalho, um novo processo foi testado e redesenhado para a extração de PHAs em culturas mistas, verificando-se até aqui uma redução dos custos e da toxidade do processo, com a possibilidade de remover totalmente o passo de solubilização do polímero num solvente orgânico.
Polyhydroxyalkanoates (PHA) are biodegradable polyesters produced by a variety of organisms. Their characteristics are very similar to those found on plastics, making them a viable replacement for this important product. Inside cells, PHA are produced under the form of inclusion bodies, and its extraction is required. Surfactants are compounds able to carry out PHA extraction by incorporating, and consequently saturating, the bacterial membrane, facilitating the lysis process. In this thesis, we begun by testing the extraction efficiency of a screening of surfactants, and some ionic liquids, on mixed cultures. Tween 20 stood out from the rest, as the PHA biofilm obtained was free from any surfactant and was possible to isolate and analyse the polymer efficiently. Using Tween 20 as extractive agent, more tests were carried out, where the amount of biomass, concentration of surfactant, and time of digestion were studied. As for the surfactant concentrations 50mM, 150mM, 250mM, 400mM e 500Mm, better extraction yields (56-61%) were achieved with lower concentrations (50mM and 150mM). As for digestion times (2h, 4h, 6h, 8h and 14h) and biomass quantity (0.3g and 0.8g), it was verified that with lower values and times (4h and 0.3g), results obtained were very similar, or better, than those obtained with overnight digestion and 0.8g of biomass. Chloroform was replaced by dimethyl carbonate, greatly reducing the process toxicity in the purification step. An extraction using solely surfactant digestion, without a purification step, was also performed, achieving an extraction yield of 16.17%. In addition to the similar yields obtained in this work, a new process was tested, and later redesigned, for PHA extraction in mixed cultures, with a reduction of costs and toxicity of the process, and with the future possibility of completely removing the step based on the solubilization and isolation of the polymer in an organic solvent.

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Tachon, Romain. "Apport de la chromatographie en phase liquide couplée à la spectrométrie de masse pour l'analyse de traces d'explosifs : optimisation des conditions d'extraction et de purification pour le traitement d'échantillons récupérés sur une scène d'attentat." Paris 6, 2008. http://www.theses.fr/2008PA066669.

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Les investigations menées après attentat par les services de police technique et scientifique ont pour but d’identifier la nature de la charge explosive employée mais la tâche peut se révéler particulièrement difficile d’un point de vue analytique. En effet, les résidus de charge explosive sont le plus souvent présents à l’état de traces dans des matrices variées et difficiles à traiter d’où la nécessité de disposer de protocoles analytiques performants. Ces travaux ont tout d’abord consisté à développer une méthode d’analyse basée sur le couplage entre chromatographie en phase liquide et spectrométrie de masse. L’utilisation d’un support de séparation en carbone graphite poreux et l’optimisation du couplage a rendu possible l’analyse simultanée des explosifs organiques les plus couramment rencontrés. Les effets de matrice sur les performances de la méthode ont ensuite été évalués puis éliminés en partie avec la mise en place d’une procédure de purification de l’échantillon par extraction sur phase solide. Enfin, un protocole général de traitement de l’échantillon incluant les étapes d’extraction, de purification et de concentration a été proposé puis validé avec l’analyse d’échantillons réels obtenus lors de simulations d’attentats avec engins explosifs improvisés

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Eddhif, Balkis. "Développement d'une approche analytique non ciblée pour l'étude des protéines dans les milieux complexes, environnementaux et biologiques." Thesis, Poitiers, 2017. http://www.theses.fr/2017POIT2291/document.

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Grâce aux récents progrès en terme d'instrumentation analytique, la protéomique, en tant que science qui étudie le protéome d'un organisme ou d'un milieu, a connu un véritable tournant et a permis d'étendre le champ des connaissances sur le fonctionnement du vivant dans son ensemble (structure, fonction, métabolisme, dynamisme). Néanmoins, l'étude des protéomes représente un challenge pour de nombreux biologistes, chimistes et biochimistes, en raison notamment de la complexité des échantillons étudiés. De nombreux protocoles analytiques ont d'ores et déjà été développés. Cependant, dans leur ensemble, ces stratégies sont relativement longues et multi-étapes et le plus souvent ciblées sur une protéine donnée.Dans ce contexte, ce travail de thèse a pour objectif de simplifier les protocoles expérimentaux existants afin de limiter les pertes en protéines et ainsi amplifier leurs signaux au cours d'une analyse « Bottom-up » par LC-HRMS (analyse « hors gel »). Chaque étape du processus a été décortiquée et optimisée. Dans un premier temps, les paramètres UPLC-HRMS/MS ont été optimisés afin d'améliorer la détection et la quantification des protéines présentes à des concentrations très variables dans les milieux étudiés. Ensuite, une approche de purification simplifiée qui repose sur une seule et unique étape de lavage et solubilisation des protéines a été mise au point. La démonstration de son efficacité « chimique » et « biologique » a ensuite été réalisée via une étude mécanistique au cours de laquelle les changements de conformation des protéines ont été étudiés à chacune des étapes de purification proposées. Enfin, certains paramètres influençant l'extraction des protéines à partir de ces mêmes matrices ont été étudiés afin de proposer à terme un protocole d'extraction à la carte compatible avec une analyse directe par LC-HRMS/MS
Recent advances in proteomics have been spurred by the rapid development of hybrid and/or high-resolution mass analysers (HRMS/MS). These powerful instrumentations have led to significant improvements in « Bottom-up » approach and have enabled to deepen our knowledge on the functionality of biological systems (structure, function, metabolism, dynamic, etc).Despite their high sensibilities, the potential of such instruments could be significantly lessened by an imperfect sample pre-treatment. In this context, current sample pretreatments follow multi-steps experimental workflows, which alternatively lead to low recoveries of proteins. In this line, this study aims at developing a simple and versatile strategy in order to reduce protein losses and enhance their detection in gel-free LC-MS analysis. First, an analytical method based on liquid chromatography and tandem mass spectrometry was developed to detect and quantify complex peptides mixture. Secondly, a universal, simple and fast purification approach was designed with the aim to purify protein extracts in only one-step. For this purpose, the molecular reactivity, dynamics and conformational changes of proteins at each development step were comprehensively investigated with a set of spectroscopic techniques, in order to select the best strategy. Finally, different factors influencing extraction of proteins were investigated with the goal in the long term to propose an on-demand extraction protocol for direct analysis of proteins by LC-HRMS/MS

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Holste, Angela Sarah. "Développement des méthodes bio analytique pour l’analyse quantitative et qualitative des peptides et protéines marqués par le couplage de la chromatographie et la spectrométrie de masse." Thesis, Pau, 2014. http://www.theses.fr/2014PAUU3004/document.

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Cette thèse est le résultat d’une cotutelle entre l'Université de Pau et des Pays de l'Adour (UPPA) à Pau, en France et l'Université Christian Albrecht (CAU) à Kiel, en Allemagne. Dans le cadre de cette collaboration internationale, des méthodes bio-analytiques sont développées pour analyser quantitativement et qualitativement des peptides et protéines marquées par le couplage de la chromatographie avec la spectrométrie de masse. Les peptides et les digestats des protéines sont marquées selon un protocole optimisé par des lanthanides en utilisant des composés à base de DOTA. La séparation des peptides est réalisée par IP-RP-nanoHPLC. Des données complémentaires sont acquises par MALDI-MS pour l'identification et par ICP-MS pour la quantification. Dans ce contexte, une étape de pré-nettoyage en ligne est développée et mise en œuvre dans le protocole de séparation par nanoHPLC. Cette étape permet l'élimination efficace des réactifs appliqués en excès et ainsi la diminution du bruit de fond lié à la présence de métaux lors des analyses par ICP-MS. Les données obtenues sont alors plus facile à interpréter, la sensibilité des signaux des peptides n’étant par ailleurs pas modifié. L'extraction en phase solide (SPE) appliquée comme alternative entraîne des pertes importantes de peptides et peut être considérée comme inadaptée pour l'analyse quantitative. Des additifs pour éluants de nanoHPLC, tels que l'EDTA et le HFBA sont testés et jugés non bénéfiques pour l'analyse des échantillons peptidiques normaux. HFBA peut être reconsidéré pour une application spéciale sur des peptides très hydrophiles. Des peptides marqués sont développés. Leur utilisation en quantité connue pourrait permettre la quantification rapide et simple d'un échantillon de digestat à faible complexité. De plus, cet ensemble de peptides permet la superposition fiable des chromatogrammes, et ainsi de comparer des données complémentaires obtenues par l’analyse d’échantillon par ICP-MS et MALDI-MS. Expériences d'application avec le couplage laser femtoseconde avec ICP-MS sont effectuées sur des plaques métalliques de MALDI MS et montrent des résultats très prometteurs. Pour cela, les échantillons préalablement identifiés par MALDI-MS sont analysés par fsLA-ICP-MS. Les premières tentatives de quantification sur la plaque en acier modifiée sont satisfaisantes et donnent des résultats répondant aux attentes. L’optimisation des paramètres de MALDI-MS facilite l’identification des peptides
This PhD thesis was a Cotutelle between the Université de Pau et des Pays de l’Adour (UPPA) in Pau, France and the Christian-Albrechts University (CAU) in Kiel, Germany. In the course of this international collaboration, bio-analytical methods for the quantitative and qualitative analysis of labelled peptides and proteins were developed, which were based on the hyphenation of chromatography with mass spectrometry. Peptides and protein digests were lanthanide labelled using DOTA-based compounds according to an optimised protocol. Separation on the peptide level was performed using IP-RP-nanoHPLC. Complementary data sets were acquired using MALDI-MS for identification and ICP-MS for quantification. In this context, an online precleaning step was developed and implemented in the nanoHPLC separation routine, which allowed for effective removal of excess reagents. This lead to lowered metal backgrounds during ICP-MS measurements and thus better data interpretability, while guarding peptide recovery at a maximum level. An alternative offline purification using solid phase extraction (SPE) resulted in important peptide losses and can be considered unsuitable for quantitative analysis. Additives to the nanoHPLC eluents, such as HFBA and EDTA were tested and not deemed beneficial for the analysis of normal peptide samples. HFBA can be reconsidered for special application on very hydrophilic peptide species. A set of labelled peptides was developed, which due to application of known quantities could be employed for quick and simple quantification of a low complexity digest sample. In addition this peptide set allowed for the reliable superposition of chromatograms, enabling sample comparability especially for complementary ICP-MS and MALDI-MS data. Experiments for application of fsLA-ICP-MS on MALDI-MS target plates were conducted and showed very promising results. For this purpose, samples that were already identified using MALDI-MS were supposed to be remeasured using fsLA-ICP-MS. First quantification attempts on the modified steel target plate were successful and in the range of expectance. Adjusted parameters for MALDI-MS allowed for proper peptide identifications

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Valente, Ana Isabel Bastos. "RuBisCOs’ extraction and purification: from residual biomass to value added protein." Master's thesis, 2020. http://hdl.handle.net/10773/30462.

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With the growth of the world population, new sources of proteins are needed. Vegetable biomass is a promising source, as it allows the use of agricultural crop residues with the ability to be a continuous source of biomass without harming existing ecosystems, and the extraction of biomass proteins while still fresh. Currently, with the methods used, a final product is obtained that cannot be applied in the food industry. Furthermore, the methods developed until today are not selective and do not allow simultaneously reaching purities and extraction efficiencies close to 100%. RuBisCO (Ribulose-1,5-bisphosphate carboxylase/oxygenase) is the most abundant protein (enzyme) on the planet and can be applied in the most diverse areas, from pharmaceuticals to food and feed. Thus, in this master's thesis, a new method of extracting RuBisCO and subsequent separation and purification was developed. For this purpose, aqueous solutions of biocompatible ionic liquids (ILs) (glycine-betaine analogues and cholinium derivatives) were used in the solid-liquid extraction of RuBisCO from the spinach leaf. Through the response surface methodology, the extraction conditions (pH, solid-liquid ratio, and IL concentration) were optimized. Under optimum conditions, a maximum extraction of 2.00 mg/ mL of RuBisCO and a yield of 10.93 mg of RuBisCO/ g of biomass for cholinium acetate ([Ch][Acetate]) and 1.86 mg/ mL and a yield of 10.12 mg RuBisCO / g biomass for cholinium chloride ([Ch]Cl). The optimum points determined were: solid-liquid ratio of 0.184, IL concentration of 2,68 M and a pH of 9.09 for [Ch]Cl and 11.2 for [Ch][Acetate]. After extraction, the separation and purification of RuBisCO were performed through the application of aqueous biphasic systems (ABSs). The extracts from the solid-liquid extraction with [Ch]Cl and [Ch][Acetate] containing IL and RuBisCO were individually mixed with polypropylene glycol 400 g.mol-1 (PPG 400) or polyethylene glycol 1000 g.mol - 1 (PEG 1000) and dipotassium phosphate (K2HPO4) forming two types of ABSs composed of IL and polymer or salt. After this process, it was possible to obtain a RuBisCO extraction efficiency of 100% for the IL phase in the system composed of PPG400 + [Ch][Acetate] and K2HPO4 + IL ([Ch][Acetate] and [Ch]Cl), however, it was not possible to separate RuBisCO from the remaining proteins, having demonstrated that these ABSs (IL + polymer and IL + salt) are not selective for the purification of RuBisCO.
Com o crescimento da população mundial são necessárias novas fontes de proteínas. A biomassa vegetal é uma fonte promissora, pois permite a utilização de resíduos de culturas agrícolas com a capacidade de ser uma fonte contínua de biomassa sem prejudicar os ecossistemas já existentes, e a extração de proteínas de biomassa ainda fresca. Atualmente, com os métodos utilizados, é obtido um produto final que não pode ser aplicado na indústria alimentar além de que, os métodos até hoje desenvolvidos não são seletivos nem permitem atingir simultaneamente purezas e eficiências de extração próximas de 100 %. A RuBisCO (Ribulose-1,5-bifosfato carboxilase/oxigenase) é a proteína (enzima) mais abundante no planeta e pode ser aplicada nas mais diversas áreas, desde a farmacêutica à alimentar e de rações. Deste modo, nesta tese de mestrado foi desenvolvido um novo método de extração da RuBisCO e posterior separação e purificação. Para tal, foram usadas soluções aquosas de líquidos iónicos (LIs) biocompatíveis (análogos da glicina-betaína e derivados de colínio) na extração sólido-líquido da RuBisCO da folha do espinafre. Através da metodologia de superfície de resposta, foram otimizadas as condições da extração (pH, razão sólido-líquido e a concentração de LI). Nas condições ótimas, foi obtida uma extração máxima de 2.00 mg /mL de RuBisCO e um rendimento de 10.93 mg de RuBisCO /g de biomassa para o acetato de colínio ([Ch][Acetato]) e 1.86 mg /mL e um rendimento de 10.12 mg de RuBisCO /g de biomassa para o cloreto de colínio ([Ch]Cl). Os pontos ótimos determinados foram: razão sólido-líquido de 0.184, concentração de LI de 2.68 M e um pH de 9.09 para o [Ch]Cl e 11.2 para o [Ch][Acetato]. Após a extração, a separação e a purificação da RuBisCO foi realizada através da aplicação de sistema aquoso bifásicos (SABs). Os extratos provenientes da extração sólido-líquido com [Ch]Cl e [Ch][Acetato] que contêm LI e RuBisCO foram misturados individualmente com polipropileno glicol 400 g.mol-1 (PPG 400) ou polietileno glicol 1000 g.mol-1 (PEG 1000) e fosfato dipotássico (K2HPO4) formando-se dois tipos de SABs compostos por LI e polímero ou sal. Após este processo foi possível obter uma eficiência de extração da RuBisCO de 100% para a fase de LI no sistema composto por PPG400+ [Ch][Acetato] e por K2HPO4 + LI ([Ch][Acetato] e [Ch]Cl), no entanto, não foi possível separar a RuBisCO das restantes proteínas, tendo demonstrado estes SABs (LI+polímero e LI+sal) não serem seletivos para a purificação da RuBisCO.
Mestrado em Biotecnologia

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Rocha, Ana Mafalda Rodrigues Almeida. "Development of purification platforms for immunoglobulin y using aqueous biphasic systems." Doctoral thesis, 2018. http://hdl.handle.net/10773/24863.

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With the increase of antibiotic-resistant microorganisms and diseases that are unresponsive to conventional drugs, it is imperative the development of alternative, economical and effective therapeutics. The use of biopharmaceuticals, and in particular antibodies/immunoglobulins, is a promising alternative over common synthetic pharmaceuticals. Among these, antibodies obtained from chicken egg yolk, namely immunoglobulin Y (IgY), can be obtained in high titers by non-invasive methods, opening the door to low-cost biopharmaceuticals. Nevertheless, the production cost of high-quality and high-purity IgY remains higher than other drug therapies due to the lack of cost-efficient purification techniques. Aiming at producing IgY that could ultimately be used as a recurrent and widespread biopharmaceutical, this work is focused on the selective extraction of IgY from egg yolk using aqueous biphasic systems (ABS) as alternative purification platforms. Since egg yolk is a complex matrix, a first step including the lipids/lipoproteins precipitation and the water-soluble protein fraction (WSPF) recovery is required. The WSPF was recovered and characterized by mass spectrometry (LC‑MS/MS) and the main proteins identified (IgY, serum albumin (α-livetin), ovalbumin, ovotransferrin, vitellogenin 1 and vitellogenin 2). ABS composed of ionic liquids (ILs) and polymers or salts were initially investigated to purify IgY from the egg yolk WSPF, namely ABS composed of biocompatible and self-buffering ILs and PPG 400 (poly(propylene) glycol) or K3C6H5O7. This study allowed to conclude on the ILs cation and anion, and polymer and salt effects on the selective extraction of IgY to one of the ABS phases. Subsequently, polymer-salt-based ABS were investigated, namely ABS composed of PEG (polyethylene glycol) and Na2SO4 or phosphate salt buffer (K2HPO4/ KH2PO4, pH 5.5 - 8.0). These systems were also applied in centrifugal partitioning chromatography (CPC) while foreseeing the technology scale-up. The effect of the molecular weight of PEG, pH, mixture composition of the ABS, and CPC operating conditions (mobile phase flow rate, rotation, and the operation mode) were evaluated. The IgY stability/activity in various aqueous solutions of ILs, salts, and polymers was assessed. The best results regarding purity and yield of IgY were obtained with polymer-based ABS. In particular, the ABS composed of 18 wt% PEG 1000 + 13 wt% phosphate buffer at pH 6.0 allows obtaining IgY with a purity of 39% and yield of 100% in a single step. By the application of this ABS in CPC, IgY with a purity of 51% was obtained
Com o aumento de microrganismos resistentes a antibióticos e doenças que não respondem a terapias comuns, torna-se fundamental o desenvolvimento de terapias alternativas, económicas e eficazes. A utilização de biofármacos, e em particular anticorpos/imunoglobulinas, é uma alternativa promissora relativamente aos fármacos sintéticos comuns. Dentro da classe dos anticorpos, os obtidos a partir da gema do ovo de galinha, nomeadamente a imunoglobulina Y (IgY), podem ser obtidos em quantidades elevadas por métodos não invasivos, o que pode resultar na produção de biofármacos mais acessíveis. No entanto, o custo de produção da IgY de excelente qualidade e/ ou elevada pureza é ainda superior às terapias comuns devido à escassez de técnicas de purificação rentáveis. Com o objetivo de produzir IgY que possa ser utilizado como um biofármaco recorrente e comum, este trabalho foca-se no estudo de sistemas bifásicos aquosos (SAB) como plataformas de purificação alternativas. Uma vez que a gema de ovo é uma matriz complexa, é necessário um primeiro passo de precipitação dos lipídios/lipoproteínas e recuperação da fração de proteínas solúveis em água (FPSA). A FPSA foi caracterizada por espectrometria de massa (LC-MS/MS) e as principais proteínas presentes nesta fração foram identificadas (IgY, albumina sérica (α-livetina), ovalbumina, ovotransferrina, vitelogenina 1 e vitelogenina 2). Primeiramente foram estudados SAB constituídos por líquidos iónicos (LIs) e polímeros ou sais para a purificação da IgY a partir da FPSA, nomeadamente SAB constituídos por LIs biocompatíveis e capacidade tampão e PPG 400 (polipropilenoglicol) ou K3C6H5O7. Este estudo permitiu avaliar o efeito do catião e do anião dos LIs, do polímero e do sal na extração seletiva da IgY para uma das fases dos SAB. Posteriormente, foram investigados SAB constituídos por polímeros e sais, nomeadamente SAB compostos por PEG (polietilenoglicol) e Na2SO4 ou tampão fosfato (K2HPO4/ KH2PO4, pH 5,5 - 8,0). Estes sistemas também foram aplicados em cromatografia de partição de força centrífuga (CPC) visando a sua aplicação em larga escala. Avaliou-se o efeito do peso molecular do PEG, o valor de pH, a composição do SAB, e as condições operacionais da CPC (fluxo da fase móvel, rotação e modo de operação). A estabilidade/atividade da IgY foi também avaliada em várias soluções aquosas de LIs, sais e polímeros. Os melhores resultados em termos de pureza e rendimento de IgY foram obtidos com o SAB do tipo polímero-sal. Em particular, o SAB constituído por 18% de PEG 1000 + 13% de tampão fosfato a pH 6,0 permite obter IgY com uma pureza de 39% e um rendimento de 100% num único passo. Pela aplicação deste SAB em CPC, obteve-se IgY com uma pureza de 51%
Programa Doutoral em Bioquímica

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34

Dinis, Teresa Beatriz Vide. "Characterization and development of aqueous biphasic systems envisioning their application in the purification of nucleic acids." Doctoral thesis, 2020. http://hdl.handle.net/10773/30469.

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Non-viral vectors, such as plasmid deoxyribonucleic acid (pDNA), are gaining momentum in gene therapy. However, the pDNA manufacture still requires the development of cost-effective downstream bioprocesses, able to correspond to all requirements of regulatory agencies and to provide high quantities of these biotherapeutics at lower cost. Amongst the possible downstream processes for pDNA, aqueous biphasic systems (ABS) composed of ionic liquids (ILs) were investigated in this thesis, since IL-based ABS allow to circumvent some technical limitations of the traditional polymer-polymer and salt-polymer ABS, namely the lack of tailored extraction performance and improved selectivity. Despite their potential, there is still a deficiency in the investigation of IL-based ABS to purify nucleic acids. Based on the exposed, this thesis starts with the development of a model to predict the formation of IL-based ABS, which will allow their faster analysis and design to a specific application, followed by the characterization of novel IL-based ABS comprising mixtures of polymers or mixtures of ILs towards a better understanding of the mechanisms ruling the ABS formation. These fundamental studies are essential towards the optimization of IL-based ABS as separation strategies. Finally, the implementation of IL-based ABS to purify DNA-based therapeutics was investigated. In this context, a new model, able to predict with good accuracy the formation of IL-based systems, was developed, based on thermodynamic calculation models and information taken from pure ILs. Thereafter, the determined phase diagrams and partition coefficients of the two novel types of IL-based ABS comprising mixtures of polymers or mixtures of ILs allowed to conclude that ABS with mixtures of ILs do not behave as pseudo-ternary systems, contrarily to ABS composed of mixtures of polymers. Based on the tunable character of IL-based ABS, phase-forming components were successfully designed and demonstrated to be able to preserve the DNA stability, while allowing the selective separation of the deoxyribonuclease I (DNase I) enzyme from the target nucleic acid. As evidenced in this thesis, IL-based ABS have the potential to perform “one-pot” extraction, purification and long-term preservation of DNA, being promising candidates to integrate several downstream steps in the pDNA manufacture.
Os vetores não-virais, tais como os ácidos desoxirribonucleicos plasmídicos (pADN), estão a ganhar relevância na terapia genética. No entanto, o bio processamento de pADN deve satisfazer as normas regulamentares e permitir a sua produção em elevada quantidade e a um menor custo. Entre os possíveis processos de extração e purificação de pADN, nesta tese foram estudados sistemas aquosos bifásicos (SAB) constituídos por líquidos iónicos (LI), uma vez que estes sistemas são capazes de “contornar” as principais limitações técnicas associadas aos SAB tradicionais compostos por polímeros e sais, nomeadamente baixa eficiência de extração e baixa seletividade. Apesar do seu potencial, os SAB constituídos por LIs têm sido ainda pouco estudados na purificação de ácidos nucleicos. Face ao exposto, a presente tese inicia-se com o desenvolvimento de um modelo capaz de prever a formação de SAB constituídos por LIs, que permita uma análise e seleção mais rápidas de um determinado SAB para uma aplicação específica, seguido da caracterização e otimização de novos SAB constituídos por misturas de polímeros ou misturas de LIs de forma a obter informação acerca dos mecanismos de formação destes sistemas. Estes estudos fundamentais permitem otimizar SAB constituídos por LIs enquanto processos de separação. Finalmente, foram implementados SAB constituídos por LIs na purificação de ADN. Neste contexto, foi desenvolvido um modelo capaz de prever com precisão a formação de SAB compostos por LIs, recorrendo a modelos de cálculo termodinâmico e propriedades de LIs puros. Os diagramas de fase e os coeficientes de partição determinados para os novos SAB constituídos por misturas de polímeros ou misturas de LIs permitiram concluir que os SAB constituídos por misturas de LIs não apresentam um comportamento de sistemas pseuso-ternários, contrariamente aos SAB com misturas de polímeros. Por fim, a comprovada versatilidade dos SAB constituídos por LIs permitiu identificar SAB capazes de assegurar a estabilidade do ADN e a separação da enzima desoxirribonuclease I do ácido nucleico. Tal como evidenciado nesta tese, os SAB constituídos por LIs apresentam potencial para extrair, purificar e preservar, simultaneamente, o ADN, sendo candidatos promissores para integrar vários passos no bio processamento de pADN.
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35

Ruan, Xian-Sheng, and 阮咸盛. "Ionic liquids based extraction of resveratrol from the fermented powder of Polygonum cuspidatum and the following purification." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/02664932599860731382.

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碩士
國立臺灣大學
化學工程學研究所
101
Resveratrol, one of the polyphenolic compounds, is commonly found in grapes, peanuts, mulberries and Japanese knotweeds. Since the French Paradox was first described in 1979, there has been an increased focus on resveratrol due to its health benefits. Aside from its cardioprotective effects, resveratrol is considered to possess anti-oxidative, anti-carcinogenic, anti-inflammatory, and anti-aging activities, mitigate Alzheimer’s disease, and prevent diabetes. It is worth noting that, while resveratrol’s mechanism of actions involved in these diseases remain elusive, it has promising applications in the fields of pharmaceuticals and dietary supplements. A number of methods have been used for extracting resveratrol. Among them, ultrasound-assisted extraction method has several advantages, including simplicity, cost-effectiveness, and, nice extraction efficiency. To increase the amount of resveratrol, we used ionic liquids to extract resveratrol from the powder of fermented Polygonum cuspidatum. Ionic liquids are organic salts which are composed of anion and cation and have melting points below 100oC. Ionic liquids possess diverse properties, including non-volatility, high viscosity, a wide range of liquid phase, good chemical and thermal stabilities. Their excellent salvation capacity for many inorganic and organic substances is suitable for extraction. Several investigations have indicated that the extraction efficiency or the selectivity of the target products could be enhanced by using the ionic liquid-based extraction method. In this study, 1.0M [BMIM] [Br] (aq) was used to extract resveratrol. We found in this study that, while a high selectivity between resveratrol and emodin was obtained when 1.0M [BMIM] [Br] (aq) was used in the extraction step, a further purification/separation step was needed to obtain the product with higher purities. Given that the majority of the published work only focused on the examination of the optimum conditions of extraction with no further purification/separation of the target compounds, we performed liquid-liquid extraction using ethyl acetate to separate resveratrol from the crude extract. Our results demonstrated that the recovery and purity of resveratrol in the final product was found to be approximately 80% and 40%, respectively.

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Quental, Maria João Valente. "Aqueous biphasic systems for the purification and preservation of biologically active compounds." Doctoral thesis, 2019. http://hdl.handle.net/10773/29439.

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Events involving biomolecules with biological activity have a central role in biological processes and functions. Based on their relevance, the development of techniques for their separation/purification without compromising their stability and biological activity is of upmost importance. In this work, aqueous biphasic systems composed of ionic liquids (IL-based ABS) were investigated as alternative techniques for the extraction, purification and preservation of bioactive compounds. The biocompounds investigated comprise antioxidants, amino acids, proteins (including antibodies), and nucleic acids. It is first demonstrated the development of new ABS comprising tetraalkylphosphonium- and tetraalkylammonium-based ILs and carbohydrates or amino acids as salting-out agents. These systems proved to be competitive extraction platforms for antioxidants and aromatic-aliphatic amino acid mixtures when compared to more conventional ABS. Furthermore, it was demonstrated that it is possible to recover the target compounds by a solid-phase extraction step, allowing the IL recycling. In the following set of works, novel ABS for the separation of proteins were considered. Self-buffering ILs of a biological-derived nature were synthesized and used to form ABS to extract bovine serum albumin. In the same line, cholinium-based ILs combined with anions derived from natural acids were combined with a polymer to form ABS to extract antibodies, namely immunoglobulin G (IgG). In both works, the complete extraction of the proteins to the IL-rich phase was achieved in a single step, without compromising the proteins integrity. The last set of works is related with the use of ILs aqueous solutions and IL-based ABS to preserve and extract nucleic acids. It was demonstrated that the RNA integrity and stability are maintained in aqueous solutions of appropriate ILs, and that most ILs at 20 wt% display no cytotoxicity towards human cell lines. Finally, ABS were investigated as integrated extraction-preservation strategies. RNA completely partitions to the IL-rich phase in one-step, which could act as the preservation medium. In both works, RNA was successfully recovered and the IL recycled. Although additional research is still required, the high versatility of IL-based ABS as alternative extraction and preservation media was demonstrated in this thesis, while highlighting their potential to be used in a variety of biotechnological processes.
As biomoléculas com atividade biológica apresentam um papel central em diversos processos e funções biológicas. Dada a sua importância, o desenvolvimento de técnicas de separação/purificação que não comprometam a sua estabilidade e atividade biológica é de extrema relevância. Neste trabalho, foram estudados sistemas aquosos bifásicos constituídos por líquidos iónicos (LI-SABs), para a extração, purificação e preservação de compostos bioativos. Os biocompostos estudados compreendem antioxidantes, aminoácidos, proteínas (incluindo anticorpos) e ácidos nucleicos. Inicialmente foram estudados SABs constituídos por LIs com catiões da família do tetrabutilfosfónio e tetrabutilamónio, e hidratos de carbono ou aminoácidos como agentes de salting-out. Estes novos sistemas demonstraram ser plataformas de extração muito competitivas quando comparados com os SABs convencionais na extração de antioxidantes e de misturas de aminoácidos alifáticos-aromáticos, permitindo ainda a recuperação dos compostos alvo através de uma etapa de extração em fase sólida e a reciclagem do LI. Nos trabalhos seguintes, foram desenvolvidos novos SABs para a extração e purificação de proteínas. Foram sintetizados LIs com capacidade tampão e aplicados na formação de SABs para a extração da albumina do soro de bovino. Posteriormente, SABs constituídos por um polímero e por LIs compreendendo o catião colinío e aniões derivados de ácidos naturais foram desenvolvidos para a extração de anticorpos, nomeadamente imunoglobulina G (IgG). Com estes sistemas foi possível, numa única etapa, a extração completa de ambas as proteínas para a fase rica em LI, sem comprometer a sua estabilidade. O último conjunto de trabalhos desenvolvido foca-se na aplicação de soluções aquosas de LIs para a estabilização e preservação de ácidos nucleicos, nomeadamente o ácido ribonucleico (RNA). Nestes trabalhos provou-se ser possível manter a integridade e estabilidade do RNA em soluções aquosas de LIs, e que a maioria dos LIs a 20% não apresentam citotoxicidade para linhas celulares humanas. Finalmente, avaliaram-se SABs como estratégias integradas de preservação-extração. O RNA foi extraído na totalidade e num único passo para a fase rica em LI, que pode atuar como meio de preservação. Em ambos os trabalhos, o RNA foi recuperado e o LI reciclado. Embora ainda sejam necessários alguns estudos adicionais, nesta tese demonstrou-se a versatilidade de SABs constituídos por LIs como técnica alternativa de extração e preservação, destacando-se também o seu potencial de aplicação em diversos processos biotecnológicos.
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37

Custódio, Margarida Henriques. "Bioprivileged Fluorinated Ionic Liquids in the Purification of Proteins: Towards Enhanced Tunability of Aqueous Biphasic Systems." Master's thesis, 2021. http://hdl.handle.net/10362/125765.

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Proteins are high value biomolecules with application in several fields, therefore the study of novel extraction methods using more biocompatible techniques is in large extent. Aqueous Biphasic Systems are increasingly being studied for that purpose, due to presenting two aqueous phases, usually protein-friendly. Fluorinated Ionic Liquids (FILs) are an emerging category of Ionic Liquids due to their unique properties, namely self-aggregation behavior, and already showing protein benign behavior. In this work, Lysozyme was used as model protein, and used to be partitioned by systems composed by IL and FIL, besides several salting-out agents, specifically inorganic salt, carbohydrates and a dihydrogen phosphate choline ([N1112OH][H2PO4]). These studies revealed favored partition to FIL-aqueous rich phase comparing with IL-rich phase. Lysozyme activity was tested for each component and after partition protocol, and maintained for most cases. Turbidimetry was used to infer the presence of some interactions between the protein and some systems elements; Tryptophan Intrinsic Fluorescence studies were carried to verify some conformation changes in the presence of IL, FIL and N1112OH][H2PO4]. Then, nano-Differential Scanning Calorimetry (nano-DSC) was used to confer the maintenance of thermal stability of Lysozyme, and determination of melting temperature (Tm). These studies have revealed the presence of some interaction between IL/FIL and protein, besides different conformational changes in Lysozyme provoked by these compounds compared to reference. Also, was observed a decrease on Tm with increasing IL and FIL concentration, however at partition conditions, FIL presented more Tm conservation than IL. This work permitted a higher insight on FIL application in ABS for protein extraction, and reveled their promising assets for this end; however more studies relatively to Lysozyme structure and thermodynamic parameters in the presence of IL/FIL are needed.
As proteínas são biomoléculas de elevado valor e aplicabilidade em diversas áres, desta forma o estudo de novas formas para a sua extração usado metodologias mais biocompatíveis é cada vez mais aprofundado. Os Sistemas Aquosos Bifásicos são cada vez mais estudados para este efeito, por apresentarem duas fases aquosas, tornando-os sistemas de extração mais biocompatíveis. Os Líquidos Iónicos Fluorados (FIL) são uma categoria de Líquidos Iónicos (IL) emergente devido às suas características únicas, nomeadamente a sua capacidade de fazerem “self-aggregations” e demonstrarem propriedades compatíveis com as proteínas. Neste trabalho, a Lisozima foi usada como modelo e usada para estudo da partição em sistemas aquosos bifásicos compostos por IL, para além de uma variedade de agentes de “salting-out”, especificamente sais inorgânicos, carbohidratos e colina dihidrogenofostato ([N1112OH][H2PO4]). Estes estudos revelaram uma partição maioritária para as fases ricas em FIL, em comparação com as fases ricas em IL. A atividade enzimática foi também testada para cada componente e após o procedimento de partição, e mantida para a maioria dos casos. Turbidimetria foi usada para aferir a presença de interações entre a proteína e alguns compostos usados na partição; Fluorescência Intrínseca do Triptofano foi usado para verificar algumas alterações conformacionais na presença de IL, FIL e [N1112OH][H2PO4]. Em seguida, nano-Calorimetria de Varrimento Diferencial (nano-DSC) foi usada para conferir a manutenção da estabilidade térmica da Lisozima provocada por estes componentes e determinação da Temperatura de Fusão (Tm). Estes estudos revelaram a presença de interações entre o IL/FIL e a proteína, para além de diferentes alterações na conformação provocados por estes compostos, comparando com a referência em água. Foi também verificada uma diminuição de Tm com o aumento da concentração de IL e FIL, contudo às condições de partição, o FIL apresentava maior conservação da Tm. Este trabalho permitiu uma maior análise da aplicação de FILs em ABS para extração das proteínas, e revelou características únicas para este fim; contudo são necessários mais estudos relativamente à estrutura da Lisozima e aos parâmetros termodinâmicos na presença de IL e FIL.

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38

Capela, Emanuel Augusto Vieira. "Innovative and sustainable platforms for the downstream processing of antibody-based biopharmaceuticals." Doctoral thesis, 2022. http://hdl.handle.net/10773/33484.

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Antibodies, and in particular immunoglobulin G (IgG), are considered as one of the spearheads of the biopharmaceutical industry, presenting high relevance for the treatment of several diseases and being sometimes the only available therapy for some pathologies. Despite their wide potential, the extraction and purification of these biomolecules from their complex biological media with high quality and purity is still based on multi-step approaches and is of high cost. Therefore, the development of alternative and cost-effective downstream processes able to provide high amounts of therapeutic antibodies at lower cost is highly demanded. Novel ionic-liquid-based (IL-based) strategies for the downstream processing of antibodies were investigated in this PhD thesis. ILs were chosen mainly due to their designer solvents character. This feature of ILs allows to tailor the polarity, interactions and selectivity of the developed processes, allowing to overcome some technical limitations of the conventional ones. Three types of IL-based platforms for antibodies downstream processing were investigated, namely aqueous biphasic systems (ABS), three-phase partitioning (TPP) and supported ionic liquids (SILs). ABS containing ILs as adjuvants were investigated, allowing the extraction and purification of human antibodies (polyclonal and monoclonal antibodies) with good performance in a single-step. More biocompatible and sustainable ILs were also studied as phase-forming compounds of ABS, while showing the possibility of using TPP approaches based on ABS for the purification and recovery of human antibodies. Finally, new chromatographic matrices were proposed based on SILs materials, able to capture and/or purify antibodies from their complex biological media through two different mechanisms, namely through the flowthrough-like and bind-and-elute-like modes. In summary, in this PhD thesis it is shown that ILs, if properly designed, can be successfully applied in the extraction, purification and/or recovery of human antibodies, being promising alternative platforms for the downstream processing of antibody-based biopharmaceuticals.
Os anticorpos, e em particular a imunoglobulina G (IgG), são considerados uma das pontas de lança da indústria biofarmacêutica, apresentando elevada relevância para o tratamento de várias doenças e sendo, por vezes, a única terapia disponível para algumas patologias. Apesar do seu amplo potencial, a extração e purificação destas biomoléculas a partir dos seus meios biológicos complexos com elevada qualidade e pureza é ainda baseada em abordagens com várias etapas e com elevado custo associado. Portanto, o desenvolvimento de processos a jusante alternativos, económicos e eficientes, capazes de fornecer elevadas quantidades de anticorpos terapêuticos a um custo reduzido é altamente necessário. Novas estratégias baseadas em líquidos iónicos (LIs) foram então investigadas nesta tese de Doutoramento para o processamento a jusante de anticorpos. Os LIs foram escolhidos principalmente devido ao seu carácter de solventes customizáveis. Esta característica dos LIs permite adequar a polaridade, interações e seletividade dos processos desenvolvidos, permitindo superar algumas limitações técnicas dos processos convencionais. Três tipos de plataformas baseadas em LIs foram investigadas para o processamento a jusante de anticorpos, nomeadamente sistemas aquosos bifásicos (SAB), partição trifásica e líquidos iónicos suportados. SAB contendo LIs como adjuvantes foram investigados, permitindo a extração e purificação de anticorpos humanos (anticorpos policlonais e monoclonais) com um bom desempenho em uma única etapa. LIs mais biocompatíveis e sustentáveis foram também estudados como compostos formadores de fases de SAB, demonstrando em simultâneo a possibilidade de utilizar abordagens de partição trifásica baseadas em SAB para a purificação e recuperação de anticorpos humanos. Finalmente, foram propostas novas matrizes cromatográficas baseadas em líquidos iónicos suportados, capazes de capturar e/ou purificar anticorpos a partir dos seus meios biológicos complexos através de dois mecanismos distintos, nomeadamente através dos modos negativo e positivo. Em suma, nesta tese de Doutoramento foi demonstrado que os LIs, se adequadamente concebidos, podem ser aplicados com sucesso na extração, purificação e/ou recuperação de anticorpos humanos, sendo plataformas alternativas promissoras para o processamento a jusante de biofármacos baseados em anticorpos.
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