Tesis sobre el tema "Lignine sulfatée"

Ce travail sur l’amélioration de la protection solaire suivant un concept éco-participatif propose 2 parties, (i) l’élaboration d’une formulation simple, (ii) la synthèse d’une mélanine de substitution. La formulation contient seulement 8 ingrédients, dont 2 filtres organiques sélectionnés sur leur photostabilité, caractéristiques physicochimiques, et l'absence d'impact (santé, écosystèmes), le BEMT et le DHHB. Une protection totale est atteinte par l’addition de lignine sulfatée (LiS), polymère largement disponible, non toxique, antiradicalaire et soluble dans l’eau. Des méthodologies expérimentales ont permis de minimiser les concentrations, débouchant sur 2 formules stables, SPF30 et SPF50, contenant respectivement 9 et 12% de filtres, et 5% de LiS chacune. De l'effet booster observé, des hypothèses sur les interactions LiS-filtres sont émises. La deuxième partie concerne la production de pyomélanine. Alors que les quantités produites par les microorganismes restent faibles, 3 procédés sont comparés: une autooxydation du HGA-Mn2+ (rendement 0,317 g/g de substrat), une culture induite d’Halomonas titanicae (0,55 g/L), et une polymérisation par une laccase (PyoENZ, 1,25 g/g). Les 3 structures ont été caractérisées par 13C RMN (CP-MAS) et FTIR, une réaction de décarboxylation biologique partielle conduit à la formation d'alcool gentisique et de gentisaldéhyde incorporés dans le polymère. PyoENZ est hyperthermostable, non (photo)cytotoxique, piège les ROS, réduit efficacement le Fe3+, et est proposée pour des applications
This work on the improvement of solar protection according to an eco-participatory concept proposes 2 parts, (i) the elaboration of a simple formulation, (ii) the synthesis of substitute melanin. The formulation contains only 8 ingredients, including 2 organic filters selected on their photostability, physicochemical characteristics, and absence of impact (health, ecosystems), BEMT and DHHB. Total protection is achieved by the addition of lignosulfonate (LiS), a widely available, non-toxic, anti-free radical, and a water-soluble polymer. Experimental design allowed to minimize the concentrations, resulting in 2 stable formula, SPF30 and SPF50, containing 9 and 12% filters respectively, and 5% LiS each. From the observed booster effect, hypotheses on LiS-filter interactions were proposed. The second part concerns the production of pyomelanin. While the quantities produced by the microorganisms remain low, 3 processes are compared: autooxidation of HGA-Mn2+ (yield 0.317 g/g substrate), an induced culture of Halomonas titanicae (0.55 g/L), and a method based on a laccase polymerization (PyoENZ, 1.25 g/g). The 3 structures had been characterized by 13C NMR (CP-MAS) and FTIR, a partial biological decarboxylation reaction was occurred and led to the formation of gentisic alcohol and gentisaldehyde which are incorporated in the polymer. PyoENZ is hyperthermostable, non-(photo)cytotoxic, traps ROS, effectively reduces Fe3+, and is proposed for applications

Chemoenzymatically synthesized low molecular weight lignin polymers have been previously found to be potent inhibitors of a number of serine proteases via allosteric mechanisms targeting heparin binding sites. Herein, we describe the creation of synthetic sulfated β-O4 lignin (SbO4L) polymer, which is more homogenous compared to previous lignins with respect to its inter-monomeric linkage. SbO4L is a selective inhibitor of thrombin and plasmin. SbO4L was found to act via a unique mechanism targeting thrombin exosite 2 in a manner similar to platelet glycoprotein Ibα (GPIbα). Advanced hemostasis and thrombosis assays demonstrated that SbO4L acts via a dual mechanism: as an anticoagulant, by allosteric inhibition of thrombin catalysis; and as an antiplatelet agent, by competing with platelet GPIbα. These mechanisms are comparable in potency to low molecular weight heparins currently used in the market, indicating that targeting exosite 2 may yield clinically useful drugs in the future. Since the β-O4 type lignin was found to be selective for thrombin and plasmin, we hypothesized that other scaffolds from lignins could be potent inhibitors of other serine proteases. In particular, we screened a library of synthetic sulfated small molecules against factor XIa – an emerging target for prophylactic anticoagulation. Our search identified a sulfated benzofuran trimer (a mimic of β-5 type linkage found in lignins) as a potent inhibitor of factor XIa. Surprisingly, this inhibitor did not compete with heparin. A plausible binding site in the A3 domain of factor XIa was proposed by using molecular modeling techniques. The binding pose demonstrated good correlation with the structure activity data from in vitro studies. Further confirmation that the apple domains were required was proved by testing the trimer against recombinant catalytic domain. A 40-fold decrease in activity was observed. A temperature-dependant perrin plot demonstrated that factor XIa undergoes a large conformational change in the presence of the trimer, which is possibly converting the enzyme back into the zymogen-like shape. In general, the synthetic sulfated lignins can act as a useful foundation to develop anticoagulant, antiplatelet, and anti-inflammatory molecules in the future.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
The processes of separation and isolation of Kraft lignin obtained have been insufficiently resear ched, since much of the lignin of liqueurs obtained industrially is burned for energy recovery and carbon sources in the industrial processes. Currently, with the technological innovation targeting the pulp and paper industries, it is increasingly importan t to obtain lignin in simple and economically viable way. In addition, it is very important to find conditions under which the proceedings begin minimum degradation into lignin structures. In this work, the concentrated liquor lignin from Kraft pulp proces s was precipitated in acid medium in different conditions of pH and variable times of exposure to acid conditions of precipitation. It was done later, ash analysis, calorific power, Scanning Electron Microscopy with X - ray Spectroscopy (SEM/EDS); Fourier Tr ansform Infrared Spectroscopy (FTIR) and Ultraviolet - Visible Spectrophotometry precipitated (UV - VIS) for the characterization of the lignins and the filtered, for the characterization of the soluble fractions. A general analysis of the results showed that the best yield has occurred in 15 minutes of precipitation time for the pH of 6.71 (less acidic) among all employees. In the second test, the precipitations were performed at pH 2, 4 and 6 and with a time of 5 and 15 minutes, in which was got better yields and lower salt content in lignin. It has been applied statistical analysis in all the results, which many of them were considered equal. Thus, the best case was considered carried out at pH 6 at the time of 5 minutes , since it uses less hydrochloric acid are to perform precipitation. In parallel, it has been done tests to assess the possibility of separate fragments of lignin and sugars. The preliminary tests were conducted with phenol, simulating the lignin, and glucose, simulating the sugars. In order t o carry out this separation was used cellulose acetate Hydrogel as stationary phase in a preparative scale. In the first test conducted in a time of 30 minutes, it was possible to observe that there was a clear separation of phenol and glucose. In the seco nd test, in which the parameters were refined, like the elution time (55 minutes), it was possible to note a great improvement in the separation. The test of fractionation was carried out in order to simulate future tests to improve the conditions of ferme ntation of residual sugar produced by hydrolysis of cellulose waste involved in the production of second - generation ethanol.
Os processos de separação e isolamento da lignina kraft obtidas são pouco estudadas, uma vez que grande parte da lignina de licores obtidos industrialmente é queimado para recuperação de energia e fontes de carbono nos processos industriais. Atualmente, com a inovação tecnológica voltada para as indústrias de papel e celulose, torna - se cada vez mais importante a obtenção de lignina de forma simples e economicamente viável. Além disso, é muito importante que as condições do processo provoquem mínimas degradações nas estruturas da lignina. Neste trabalho, a lignina a partir da pasta de lixívia concentrada do processo kraft foi precipitada em meio ácido, em diferentes condições de pH e tempos de exposição variáveis a condições ácidas da precipitação. Posteriormente foi realizado análise de cinzas, poder calorífico, microscopia eletrônica de varredura com detector de energia dispersa de raio s - x (MEV/EDS), espectroscopia de infravermelho por transformada de Fourier (FTIR) e espectrofotometria no ultravioleta - visível (UV - VIS). Os precipitados foram empregados na caracterização das ligninas e os filtrados, na caracterização das frações solúveis. A análise geral dos resultados mostrou que o melhor rendimento ocorreu em 15 minutos de tempo de precipitação para o pH de 6,71 (menos ácida) entre todos os processos. No segundo teste as precipitações foram realizadas em pH 2, 4 e 6 e com tempo de 5 e 15 minutos, nas quais se obtiveram melhores rendimentos e menores teores de sais na lignina. Foi aplicada análise estatística em todos os resultados. A condição mais eficaz foi obtida em pH 6 no tempo de 5 minutos. Em paralelo, foram realiza dos os testes para avaliar a possibilidade de separação de fragmentos de lignina e açúcares. Os testes preliminares foram realizadas com fenol, simulando a lignina, e glicose, simulando os açúcares. Para realizar esta separação foi usado acetato de celulos e hidrogel como fase estacionária em uma escala preparativa. No primeiro teste realizado em um tempo de 30 minutos, foi possível verificar a separação de fenol e glicose. No segundo teste, em que os parâmetros foram refinados, como o tempo de eluição (55 minutos), foi possível ver uma grande melhoria na separação. O teste de fracionamento foi realizado, a fim de simular ensaios futuros para melhorar as condições de separação dos açúcares residuais produzidos pela hidrólise de resíduos de celulose envolvido na produção de etanol de segunda geração.

Les lignines sont des polymères naturels et renouvelables. C’est le polymère le plus abondant sur la terre après la cellulose. De nos jours, les lignines sont sous-exploitées et seulement 2 % de la lignine est valorisée par an, leur application capital restant comme combustible dans les industries papetières pour la production d'énergie. Au Québec, 130 000 tonnes de liqueur noire contenant de la lignine pourraient être extraites par an afin de les valoriser, sans perturber la production dans ces industries papetières. Sa valorisation pourrait contribuer à créer de nouveaux produits à valeur ajoutée tels que les biocomposites avec une matrice de polyéthylène, polystyrène recyclé ou encore le bois. Ces nouveaux produits de ces industries pourraient améliorer la situation économique dans ce domaine, mais aussi pourraient apporter de nouvelles connaissances dans le domaine des écomatériaux tout en contribuant à la diminution des gaz à effet de serre en favorisant le produit naturel contre le produit de synthèse. Les structures des lignines diffèrent selon certains paramètres (origine, le processus d'isolation ...). Dans ce projet, deux lignines Kraft seront précipitées à partir de liqueur noire de deux industries papetières québécoises en utilisant du dioxyde de carbone comme réactif. Ces lignines seront purifiées et comparées analytiquement à d’autres lignines; une lignine Kraft commerciale, une lignine pyrolytique et une lignine Protobind Soda 2400. Connaissant la structure des lignines, il sera plus facile de les modifier. Les lignines Kraft ont été estérifiées avec l'anhydride maléique et l'anhydride succinique et comparée aux lignines non modifiées par plusieurs techniques d'analyse telles que FT-IR, TGA, DSC, RMN. Les lignines Wayagamack maléatées et non maléatées ont été incorporées dans un biocomposite de polystyrène recyclé et les propriétés mécaniques et thermiques ainsi que la morphologie ont été étudiées. Les composites avec la lignine non modifié ont montré de bonnes propriétés mécaniques et thermiques par rapport au composite avec la lignine maléate où la lignine maléatée était pourtant compatible avec le polystyrène recyclé. Les lignines Windsor non estérifiée et succinate ont été utilisées en tant que liant dans un panneau de bois et leurs propriétés mécaniques ont également été étudiées. Les résultats ont montré les meilleures propriétés mécaniques pour le panneau de bois contenant de la lignine Kraft non modifié. Les réactions de condensation de la lignine Kraft au cours de la compression à chaud du panneau améliorerait la solidité du panneau contrairement à des réactions d'estérification qui pourraient avoir lieu entre la lignine estérifié et les hydroxyles de bois. Mots clés : Liqueur noire, Lignine, Procédé Kraft, Estérification, Caractérisation, Composite, Valorisation, polystyrène, bois.
Lignins are renewable and natural polymers. It is the most abundant polymer on the earth after cellulose. Nowadays, lignins are not fully exploited and only 2% of lignin is valorised per year, their principal application remaining as a combustible in pulp industries for energy production. In Quebec, 130000 tons of black liquor containing lignin could be available from Kraft industry, per year, in order to valorise them, without disturbing the mill production. Its valorisation could contribute to create new value added products like bio composites with a matrix of polyethylene, recycled polystyrene or even wood. These new products of these industries could improve the economic situation in this field, but also could bring new knowledge in the eco materials field, in contributing of the decrease of greenhouse gases in favoring the natural product against the synthetic product. Lignin structure is different depending on several parameters (origin, isolation process…). In this project, two Kraft lignins will be precipitated from black liquor of two Quebecoise paper industries using carbon dioxide as the reagent. These lignins will be purified and compared analytically to others lignins; one Kraft softwood commercial lignin, one pyrolytic lignin and one Soda lignin Protobind 2400. With the knowledge of the Kraft lignin structure, it will be easier to modify these lignins. The esterified Kraft lignins with maleic anhydride and succinic anhydride will be compared to the unmodified lignin according to several analytical technical as FT-IR, TGA, DSC, NMR. Maleated and non modified Wayagamack lignins were incorporated in biocomposite of recycled polystyrene and the mechanical and thermal properties and the morphology were studied. The composite with non modified lignin showed good mechanical and thermal properties compared to the composite with maleated lignin where the maleated lignin was still compatible with the recycled polystyrene The Windsor succinated and non modified lignin were used as a binder in a wood panel and their properties were also studied. The results showed the best mechanical properties for the wood panel containing non modified Kraft lignin. Condensation reactions of Kraft lignin during the hot-pressing of the panel improve the solidity of the panel unlike esterification reactions that could take place between esterified lignin and the wood hydroxyls. Key words: Black liquor, Lignin, Kraft process, Characterisation, Esterification, Composite, Valorization, Polystyrene, Wood.

Orientadores: Rubens Maciel Filho, Eduardo Coselli Vasco de Toledo
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica
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Resumo: Em nível global, a indústria de celulose e papel está começando a experimentar os beneficios dos recentes desenvolvimentos na área de modelagem e controle de processos.Técnicas avançadas de simulação e controle oferecem ferramentas que permitem a análise e o projeto eficiente para processos multivariáveis não lineares e que envolvem o projeto, a inferência, a otimização e o controle automático do processo. A indústria de celulose utiliza cozinhadores, conhecidos como digestores, que são vasos de pressão onde os cavacos de madeira são tratados com licor de cozimento (hidróxido de s ódio e sulfeto de sódio) de composição determinada, a pressão e temperatura estabeleci das, visando a produção de polpa celulósica. Dentro deste contexto, os digestores podem ser classificados como contínuo (Kamyr) e descontínuo (Batch). O objetivo deste trabalho é estudar o processo de obtenção da polpa celulósica a partir da análise dos principais fenômenos fisico - químicos que ocorrem em um digestor kraft descontínuo. As predições a partir do modelo utilizado (Mirams e Nguyen, 1994) permitem a avaliação do comportamento dinâmico e a análise da sensibilidade paramétrica do processo, observando-se quais os parâmetros operacionais e as variáveis do processo que mais influenciam o comportamento do reator. O modelo do digestor descontínuo considera a difusão nos poros da madeira iniciada durante a impregnação dos cavacos. Outra característica do modelo é a sua adaptação de modo a considerar as reações de deslignificação como reações simultâneas de três diferentes tipos de lignina, sendo que a mais reativa reage mais rapidamente. Esta abordagem apresenta um novo ponto de vista para a teoria das três fases da reação, uma vez que seus resultados podem ser interpretados como se a reação de cada lignina fosse responsável por uma fase específica da reação (deslignificação inicial, principal e residual). Com relação à solução do modelo, esta foi baseada no Método das Linhas, a qual consiste na utilização do Método da Colocação Ortogonal para a discretização das equações parciais do modelo. A integração temporal das equações diferenciais ordinárias foi resolvida pelo integrador LSODE, (V asco de Toledo, 1999). Os resultados obtidos pelo modelo reproduziram as principais características dinâmicas do sistema, possibilitando compreender as etapas principais na obtenção da celulose sob determinadas condições operacionais do digestor. Isso permite a sua utilização para estudos de controle, otimização e projeto de reator descontínuos de forma segura e eficiente
Abstract: Global1y, the Kraft pulping process is beginning to get use of the benefits of the recent developments in the modeling area and process control. Advanced techniques of simulation and control offer tools that allow the analysis and efficient design of multivariable non-linear process, involving the optimization and the advanced control of the process. The pulp industry uses some equipment named digesters, which are pressure vessels where the chip of wood are treated with cooking liquor (sodium hydroxide and sodium sulfide) with defined composition, established pressure and temperature, aiming to the cellulosic pulp production. In this context, the digesters can be c1assified as continuous (Kamyr) and discontinuous digester (Batch). The aim of this work is to study the production process of the cellulosic pulp from the analysis of the Physical-Chemical Phenomena that occur in a discontinuous kraft digester. The predictions from the considered model (Mirams e Nguyen, 1994) allow the evaluation of the dynamic behavior and the analysis of the parametric sensitivity of the process, observing which is the operational parameter and variable of process that influence the most reactor behavior. The model for a descontinuous digester considers the diffusion into the wood pores initiated during the impregnation of the chips. Another characteristic of the model is its adaptation in order to consider the delignification reactions as simultaneously reactions with three different types of lignin, with the most reactive lignin reacting more quickly. This approach present a new point of view for the theory of three phases of the reaction, interpreting its results as if the reaction qf each lignin was responsible for a specific phase of the reaction (initial delignification, bulk and residual). Regarding the solution of the model it was based on "Line Method", which consist on usaged of Orthogonal Collocation for discretization of the partial differential equations. The temporal integration of the ordinary differential equations was solved by integrator LSODE (Vasco de Toledo, 1999). The obtained results from the model reproduced the main dynamic characteristics of the system, making possible the knowledge of the main stages in the production of the cellulose under determined operational conditions of the digester. These results can them be used in control, optimization and design studies in a safe and efficient way
Mestrado
Desenvolvimento de Processos Químicos
Mestre em Engenharia Química

The herpes virus family consists of more than hundred members that infect organisms, of which eight, differing markedly in the biology are known to infect humans. HSV- I is the most common one, causing oral lesions and sporadic encephalitis. These infections are highly prevalent affecting at least one in three individuals in the United States.The entry of the herpes virus into the cell is a two-step process. The initial step involves the cell surface heparan sulfate and glycoproteins in the viral envelope which enables the virus to penetrate into the cell. The second step is the fusion step. Depending on the nature of interaction and size of HS chain, a single chain may bind multiple viral ligands on a virion. There is substantial evidence showing that HS plays an important role in viral binding.HS is a heterogeneous, linear sulfated oligosaccharide composed of alternating glucosamine and uronic acid residues, which could specify distinct receptor for various viral ligands. HS, present on most exposed cell surfaces, make an ideal snare for the capture of most herpes viruses and may facilitate subsequent interactions with other co-receptors required for entry. Number of viruses, including HSV- I, HSV- II, HIV- I and dengue virus use sites of HS as receptors for binding to cells. Recently 2000 Liu et.al have characterized a HS based octasaccharide that binds to HSV-I gD. The distinguished feature in the composition of the octasaccharide is the presence of 3-O-sulfate glucosamine residue, which is an uncommon structural modification in HS. Its presence in the HSV-I gD binding sequence may confer specificity of interaction and assist HSV-I entry into the cell.Numerous sulfated molecules have been explored as mimics of HS in the inhibition of HSV-1 entry into cells. To date, most of the sulfated molecules screened for anti-viral activity have been carbohydrates. So, we reasoned that it should be possible to mimic critical interactions of HS with one or more viral glycoprotein using synthetic, non-polysaccharide, sulfated compounds. Further, it may be possible to mimic specific sequence(s) in HS, which play a role in HSV infection, with small synthetic, sulfated, non-carbohydrate molecules. In a search for synthetic mimics of HS as inhibitors of HSV-I infection, we screened a small, synthetic, sulfated flavonoids to discover a potent inhibitory activity arising from sulfation of a macromolecule present as an impurity in a crude natural product.The active principle was identified through an array of biophysical and chemical analyses as lignin sulfate, a heterogeneous; polydisperse network polymer composed of substituted phenylpropanoid monomers. Further, LC-MS with APCI in negative ionization mode, which have been reported in here for the first time for analysis of lignin, has been successfully used to deduce oligomeric structures present in the precursor of the active macromolecule based on the spectrum of the depolymerized lignin. This corroborates well with the structural information obtained using other analytical techniques. We hypothesize that the structural heterogeneity and polydispersity of lignin coupled with optimal combination of sulfate charge and hydrophobicity result in high potency. Given that the native lignin is inactive, lignin sulfate discovered here provides a variety of organic scaffolds that with the critical sulfate groups in space can mimic the HSV-I gD binding sequence.

Anticoagulants are used as the first line therapy for management and prevention of thrombotic disorders. Thrombin and factor Xa have been the prime targets for regulation of the coagulation cascade. In this work, a small library of 17 benzofuran derivatives were synthesized and screened against thrombin and factor Xa. The derivatives that displayed inhibitory potential were docked on the exosite-II of factor Xa using a docking protocol that was developed in our research group. These compounds were based on the β-5 structural unit found in the oligomer -'CDSO3‘, which was prepared in our lab and was found to inhibit both thrombin and factor Xa by an exosite-II mediated allosteric disruption of the catalytic triad.The results revealed that these β-5 like derivatives are inhibitory against thrombin and factor Xa, although their potency is weak. Thrombin and factor Xa appear to recognize different structural features suggesting a significant selectivity in recognition. Furthermore, a slight preference for the benzofuran scaffold was observed with factor Xa. Probing the mechanism of inhibition using Michaelis-Menten kinetics reveal that these compounds display uncompetitive inhibition of these proteases and the mechanism of inhibition is allosteric. Docking of these compounds on factor Xa were done using GOLD (Genetic algorithm for ligand docking) and the results, explain the observed inhibition profile. The computed docked poses also give an idea of the residues on the exosite-II of factor Xa critical for inhibition. The molecules studied here are radically different in terms of structure and mechanism of inhibition from any other ligand described in literature. This represents an opportunity to discover novel molecules with a possibly different pharmacological and toxicological profile.

Le but de cette these est d'etudier les modifications structurales de la lignine residuelle lors de la cuisson kraft et les stades de blanchiment des pates papetieres chimiques (stades c, d, p, o et z). La premiere partie est un rappel bibliographique des mecanismes proposes pour les reactions de la lignine lors de ces traitements. Le second chapitre concerne la mise au point de la methode d'extraction de la lignine residuelle des pates kraft, en procedant a une hydrolyse enzymatique des hydrates de carbone. Dans la troisieme partie, nous exposons les methodes que nous avons developpees pour le dosage des fonctions de la lignine (alcools, phenols, carboxyles et carbonyles). Ces methodes qui sont basees sur l'analyse par la rmn du fluor de derives fluores de la lignine, se sont montrees tres prometteuses et fiables. Enfin, le dernier chapitre regroupe les resultats des differentes analyses (uv, ir-tf, rmn, chromatographie d'exclusion sterique, dosage des methoxyles,. . . ), ceux-ci sont alors confrontes aux mecanismes donnes par la litterature

The occurrence of thrombosis in several pathophysiological conditions creates a huge need for anticoagulation therapy. Thrombin and factor Xa have been prime targets for regulation of clotting through the direct and indirect mechanism of inhibition. This work investigates chemo-enzymatically prepared oligomers of 4-hydroxycinnamic acids (DHPs) as potential anticoagulants. Oligomers were prepared through peroxidase-catalyzed oxidative coupling of 4-hydroxycinnamic acids. The products resulting from this reaction are called CDs, FDs and SDs. Structurally, these sulfated DHPs are unique and do not resemble any of the anticoagulants known in the literature.DHP oligomers were found to increase clotting times at concentrations comparable to heparin. Studies in blood and plasma show that DHPs possess an anticoagulation profile similar to enoxaparin. To understand the mechanism of action of DHPs, we studied the inhibition of thrombin, FXa, FIXa, and FVIIa in the presence and absence of antithrombin. CDs and FDs display a preference for direct inhibition of thrombin and FXa, and exhibit a high level of specificity over FIXa and FVIIa. In the presence of AT, CDs and FDs displayed weaker inhibition of FXa and thrombin suggesting that binding to AT is a competitive side reaction. SDs exhibited potent inhibition of FXa and thrombin in the absence of antithrombin, but was inactive against FIXa and FVIIa representing the best selectivity among the DHPs. For SDs, inhibition of all the pro-coagulant enzymes favored the antithrombin dependent pathway. Binding studies were performed to determine how CDs directly inhibits thrombin. Competitive binding studies suggest that CDs interacts with exosite II and disrupts the catalytic triad of thrombin. These results indicate that the preferred mechanism of CDs action is exosite II mediated allosteric disruption of thrombin. CDs appears to be the first exosite II mediated DTI and this represents a novel mechanism of inhibitor function. The inhibition characteristics of DHPs are unique and radically different in structure from all the current clinically used anticoagulants. To the best of our knowledge this dual mechanism of anticoagulation and unique binding mode has not been described as yet in literature and represents a novel strategy that our laboratory has discovered.

Il existe actuellement des motivations industrielles pour developper davantage les procedes de delignification par l'oxygene. L'objectif de ce travail est de reconsiderer les mecanismes reactionnels de o#2 sur les principaux constituants du bois et des pates chimiques, afin de surmonter les limites du procede. L'action de o#2 sur les hydrates de carbone seuls d'une pate kraft est evaluee, et un mecanisme decrivant l'origine de leur degradation est propose. L'influence d'un traitement par o#2 sur les constituants d'une pate kraft ecrue est egalement etudiee, ce qui met en evidence le role de la lignine sur la degradation de la cellulose. L'extraction de lignines residuelles permet de montrer l'influence d'un traitement intensif par l'oxygene sur leurs structures, et de predire leur comportement lors des stades de blanchiment ulterieurs. Cette etude montre que les cations des metaux de transition jouent un role important au cours des traitements par l'oxygene, leur comportement est mis en evidence par les techniques de rpe et de chimiluminescence. Les causes de la degradation de la cellulose etant etablies, des solutions sont recherchees pour y remedier : en particulier, des traitements reducteurs efficaces des pates sont ici developpes et optimises. L'ensemble des resultats obtenus permet finalement de proposer des applications pratiques, qui permettent d'intensifier l'usage de o#2, en delignification et en blanchiment, sur differents types de pate.

L'objectif de ce travail est d'analyser les effets de l'ozone sur les hydrates de carbone et la lignine contenus dans les pates a papier chimiques, et en particulier dans les pates kraft de résineux, ainsi que les conséquences de ces effets sur la qualité des pates blanchies a l'ozone, et sur les résultats obtenus dans des stades de blanchiment ultérieurs. Apres un premier chapitre consacre a une revue de la littérature sur l'ozone en milieu aqueux, sur son action sur les hydrates de carbone et la lignine, ainsi que sur son utilisation dans le blanchiment des pates a papier chimiques, un deuxième chapitre porte sur l'analyse des effets de l'ozone sur les hydrates de carbone et la lignine résiduelle d'une pate kraft de résineux, et plus globalement sur diverses pates a papier de différentes natures. Dans le troisième chapitre sont étudiés les effets des cations métalliques sur le blanchiment a l'ozone, en distinguant les cations présents dans la pate de ceux éventuellement présents dans l'eau du procédé. Le quatrième chapitre traite du cas de l'ozone dans des séquences de blanchiment sans composes chlores, et plus particulièrement des conséquences des modifications apportées par l'ozonation a la cellulose et a la lignine sur un stade de blanchiment ultérieur. L'optimisation de la séquence choisie est également réalisée. Dans le cinquième chapitre l'ensemble des résultats obtenus est explique en faisant appel, entre autres, a des techniques de détection des radicaux hydroxyles, et a des expérimentations de gamma radiolyse de l'eau. Les actions respectives de l'ozone moléculaire et des radicaux hydroxyles générés sont ainsi précisées. En conclusion les perspectives de l'utilisation de l'ozone en blanchiment sont discutées

L'etude realisee entre dans le cadre de la recherche de nouveaux reactifs non chlores pour le blanchiment papetier. Deux peroxyacides ont ete evalues : l'acide peroxyacetique et l'acide peroxymonosulfurique. La premiere partie a ete consacree a l'optimisation des procedes de blanchiment. Differents aspects de l'usage de ces reactifs en application au blanchiment des pates a papier chimiques kraft ont ete envisages. Ces travaux montrent que les peroxyacides sont des agents de blanchiment efficaces pouvant etre utilises pour la delignification de pates cellulosiques a fortes teneurs en lignine, comme pour parfaire la decoloration de pates comportant de faibles taux de lignine residuelle. Une application industielle a pu voir le jour decoulant de ces travaux. La seconde partie, a developpe l'etude de la caracterisation de lignines residuelles issues de pates traitees par les peroxyacides. Ce travail constitue en fait une reponse a des travaux anterieurs a cette these, sur l'effet activateur des peroxyacides. Les resultats obtenus par mesure en rmn#1#3c montrent que, contrairement au modele propose pour interpreter cet effet, les lignines issues des pates traitees ne presentent pas un enrichissement en unites phenoliques. En revanche, une reduction sensible de la teneur en unites aromatiques totales, assortie d'une conservation du ratio groupements phenoliques / groupements aromatiques totaux a ete note. Par ailleurs, les lignines residuelles se sont enrichies en groupements carboxyliques. Enfin, la troisieme partie, a etudie l'action de certains cations metalliques sur les peroxyacides. Ainsi, les peroxyacides sont decomposes catalytiquement par les metaux les plus couramment rencontres dans les pates, tels le fer ou le cuivre. De plus, les mecanismes de decomposition peuvent conduire a la generation de radicaux hydroxyles nefastes pour la qualite de la cellulose. D'autre part, l'etude de l'influence du cobalt s'est averee interessante, dans la mesure ou ce metal decompose efficacement les peroxyacides en conduisant a la generation d'especes sans consequence pour la cellulose, mais tres actives pour oxyder des molecules modeles de lignine. Ce point ouvre un champ d'applications potentiel des peroxyacides en blanchiment, en presence d'activateurs tels le cobalt ou encore les complexes de celui-ci.

Mise en uvre d'un procede de delignification utilisant un reacteur a lit fixe et faible temps de passage, concernant plus particulierement le traitement du bois de peuplier par les procedes a la soude, soude-anthraquinone et kraft. Dans chaque cas, l'etude cinetique fait apparaitre trois regimes distincts et confirme le role essentiel du ph. L'addition de na#2s et/ou de aq ameliore remarquablement la cinetique et la selectivite de la delignification. L'analyse des procedes montre que les reactions de recondensation de la lignine sur les fibres sont peu prononcees. Ceci permet d'obtenir plus rapidement des pates mieux delignifiees et moins degradees qu'en reacteur clos. Ce phenomene est confirme par la caracterisation chimique, spectrometrique et macromoleculaire des lignines recuperees en cours de traitement. Les resultats mettent en evidence des reactions d'hydrolyse et de degradation diverses. Ils confirment le role selectif de na#2s. Il apparait que, quel que soit le type de delignification alcaline, ces reactions de degradation sont les memes

L'obtention de pâte à papier chimique nécessite de réaliser une serie de traitements (cuisson, blanchiment) dont l'objectif principal est d'éliminer la lignine. En effet la lignine porteuse de groupements colorés entrave le blanchiment des pâtes. Dans ce travail est proposé une nouvelle méthode d'analyse des fonctions carbonyle de la lignine (responsables de la coloration des pâtes). Cette méthode met en ouvre la dérivation par la trifluoromethylphenylhydrazine suivie par une analyse quantitative en RMN #1#9F. Elle permet de doser simultanément les carbonyles aldéhydiques et cétoniques d'une part et quinoniques d'autre part. Cette méthode rapide, précise est supérieure aux méthodes décrites dans la littérature. L'optimisation du blanchiment passe par la connaissance de la structure de la lignine résiduelle. Ceci nécessite de savoir l'isoler afin de pouvoir l'analyser correctement. Une étude comparative des méthodes d'extraction de la lignine résiduelle a été réalisée. Ceci a permis de préciser les avantages et inconvénients de chacune de ces méthodes. Dans le cas de l'extraction enzymatique, la structure de la lignine n'est pas modifiée ; cependant la lignine obtenue est fortement contaminée par des protéines et par des hydrates de carbone. Dans le cas de l'acidolyse utilisant un milieu dioxane-eau (80/20 v/v) contenant 0,1 n d'acide chlorhydrique, la lignine est dépolymérisée. L'extraction en milieu acide acétique-eau-chlorure de zinc, optimisée dans l'étude, n'affecte peu les liaisons ether de la lignine issue de pâte kraft et donne des rendements élevés. Les résultats obtenus sur les lignines résiduelles issues des pâtes kraft et bisulfite ont permis de confirmer la plupart des mécanismes réactionnels décrits dans la littérature. Par ailleurs, ils ont permis également de préciser les facteurs régissant l'aptitude au blanchiment des pâtes (facilité d'une pâte à être blanchie indépendamment de la nature du réactif de blanchiment employé).

Sulfated low molecular weight lignins (LMWLs), CDSO3 and FDSO3, designed recently as macromolecular mimetics of heparin, were found to exhibit potent anticoagulant activity. Small molecules based on the same scaffold, SBD and SBT, showed promising thrombin inhibition. We were able to address the mechanism of the inhibition using Michaelis-Menten kinetics. All the molecules were found to be allosterically impairing thrombin activity using either noncompetitive or uncompetitive mechanism. Absence of competition with hirugen, an exosite 1 ligand, and competition with polymeric heparin points to exosite 2 as the site of interaction for these inhibitors. Yet mixed competition results with other exosite 2 ligands indicated that the molecules utilize different sub-sites within exosite 2 for interaction. Site-directed mutagenesis was used to pin point the key residues important for inhibition. All of all positively charged exosite 2 residues were mutated one at a time to alanine to abolish its charge. The data showed that Arg93 and Arg175 are the major residues involved in CDSO3 binding. FDSO3 showed a progressively greater defect in inhibition with double point mutations, the triple mutant Arg93,97,101Ala displayed a 50 fold drop in inhibition. A single mutant, Arg173Ala, displayed 22-fold reduction in IC50 of SBD, while Arg233Ala was the only mutation that impaired SBT inhibition. This proves the fact that inspite of the structural similarity between the two polymers and the two small molecules, thtey do not share the same binding space in exosite 2. To understand the types of interactions involved in thrombin interaction with the polymers, we resorted to salt-dependence studies. This showed that CDSO3 had fewer ionic contacts with thrombin, with most of its binding energy derived from non-ionic interactions. FDSO3 on the other hand had a balanced contribution of ionic and non-ionic forces. Thermodynamic studies showed that both polymers have a positive ΔCp of binding, which proves the involvement of electrostatic forces and signals the burial of the polar residues on thrombin exosite 2. These molecules offer a rare chance to study thrombin allostery. Little is known about the interplay between exosite 2, active site and sodium binding site. The allosteric nature of inhibition indicated that, for the first time, a link is proven to exist between exosite 2 and the active site that could be used to inhibit the enzyme. The presence of sodium was found to enhance the binding of FDSO3 at exosite 2, which establish the energetic coupling between exosite 2 and sodium binding site. The results identify novel binding sub-sites within exosite 2 that are energetically coupled to thrombin’s catalytic function and linked to the sodium binding site. The design of high affinity small molecules based on LMWLs scaffold presents major opportunities for developing clinically relevant, allosteric modulators of thrombin.

La cyclophiline B (CyPB) est une protéine qui catalyse l'isomérisation cis/trans de la liaison prolyle et qui se complexe à la cyclosporine A, un médicament immunosuppresseur. Bien que résidente des vésicules du réticulum endoplasmique et de la voie de sécrétion, la CyPB est également retrouvée dans le lait et le plasma. Deux types de site de fixation ont été mis en évidence à la surface des lymphocytes T, des récepteurs protéiques et des protéoglycannes à chaînes héparanes sulfates (HSPG). La CyPA, isoforme incapable de se fixer aux HSPG, et la CyPB ont en commun des activités chimioattractantes et la capacité à activer des voies de signalisation dépendantes du calcium. En revanche, seule la CyPB est capable d'augmenter l'adhésion cellulaire à la fibronectine via l'activation des intégrines α4β1 et α4β7. Cette activité pro-adhésive de la CyPB met en jeu un mécanisme dépendant des interactions avec les HSPG. En utilisant le modèle cellulaire HL-6O, nous avons montré l'implication des syndécan-l et -2 dans la modulation des réponses cellulaires induites par la fixation de la CyPB sur son récepteur. En utilisant l'héparine comme modèle, nous avons ensuite montré que la taille minimale du motif glycannique reconnu par la CyPB est un octasaccharide. Ce motif peut se loger dans une gouttière délimitée par les deux séquences 3KKK5 et 14YFD16 de la CyPB. L'interaction nécessite la présence de groupements N-, 2-, et 6-O-sulfates. Nos travaux sont également enfaveur de l'implication d'un groupement aminé libre porté par une glucosamine. La fréquence de tels groupements est rare, ce qui explique l'étroite sélectivité de fixation de la CyPB. L'ensemble de nos résultats suggère que les syndécan-l et -2 interviennent dans l'activité pro-adhésive de la CyPB en tant que molécules de co-activation. En outre, les chaînes héparanes de ces HSPG possèderaient des motifs structuraux particuliers responsables de la haute spécificité d'action dela CyPB.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
A few years ago, several studies have been conducted to transformatio n of raw matter into renewable biodegradable materials, since it is necessary to rethink consumption and rationalize the use of packaging derived from synthetic polymers. Among these raw materials can be detached corn starch produced worldwide, with low cost and high potential for biodegradability. In this paper, aiming a possible application in biodegradable packaging, starch polymeric films were developed using native corn starch with the incorporation of 1 to 4% of fibers sugarcane bagasse from industrial wastes, 2.5, 5 and 10% of castor oil, and 2.5, 5% epoxidized soy bean oil, and modified corn starch films with the incorporation of 1 to 3% fibers sugarcane bagasse, and 2.5, 5 % of epoxidized soybean oil. Some mechanical and thermal analysis for characterization of the films were made. The mechanical p roperties were analyzed by tensile test in Dynamic-Mechanical Thermal Analysis (DMTA) equipment. Among the films tested in tension, they stood the native corn starch films that have the best tensile strength results (1.05 MPa) and elongation at break (77.66%), followed by the native starch containing film 3% fiber (0.81 MPa) and native starch films containing 2.5% epoxidized soybean oil (58.55%). The fractured samples were analyzed by Scanning Electron Microscopy (SEM). Thermal an alysis of all kinds of developed films were made by Differential Scanning Calo rimetry (DSC), Thermogravimetric Analysis (TGA) and Thermogravimetric Analysis Derivative, where the DSC curves showed higher thermal stability for native starch films containing castor oil and epoxidized soybean, in which the thermal decomposition was observed between 270 and 291 o C, being higher than the temperatures of other films , and four stages of degradation for these films, and the others had only three stages of degradation. Native starch films with incorporation o f 3% fiber and 2.5% epoxidized soybean oil were buried in soils incubated for completion of the biodegradability test, and analysis of the emissions o f CO2, CH4, and N2O were performed by gas chromatography, it was possible to observe high CO2 emission rates in the first month of incubation for all films. After 90 days, the films were dug up, and the polymer matrix was completely biodegraded.
Há alguns anos, vários estudos têm sido realizados para transformação de matéria- prima de fontes renováveis em materiais biodegradáveis, visto que se faz necessário repensar o consumo e racionalizar a utilização de embalagens derivada s de polímeros sintéticos. Dentre estas matérias-primas pode ser destacado o amido de milho, produzido mundialmente com baixo custo e alto potencial de biodegradabilidade. Neste trabalho, visando uma possível aplicação em embalagens biodegradáveis, filmes poliméricos de amido foram desenvolvidos, utilizando amido de milho nativo, com a incorporação de 1 a 4% de fibras de bagaço de cana- de - açúcar proveniente de resíduos industriais, 2,5, 5 e 10% de óleo de mamona, e 2,5 e 5% de óleo de soja epoxidado, e filmes de amido de milho modificado com a incorporação de 1 a 3% de fibras de bagaço de cana, e 2,5 e 5% de óleo de soja epoxidado. Foram realizadas algumas análises mecânicas e térmicas para caracterização dos filmes. As propriedades mecânicas foram analisadas através de ensaio de tração em equipamento de Análise Térmica Dinâmico-Mecânica (DMT A). Dentre os filmes ensaiados em tração, se destacaram os filmes de amido de milho nativo que obtiveram os melhores resultados de resistência à tração (1,05 MPa) e a o alongamento na ruptura (77,66%), seguido do filme de amido nativo contendo 3% de fibras (0,81 MPa) e do filme de amido nativo contendo 2,5% de óleo de soja epoxidado (58,55%). As amostras fraturadas em tração foram analisadas por Microscopia Eletrônica de Varredura (MEV). Análises térmicas foram realizadas por Calorimetria Exploratória Diferencial (DSC), Termogravimetria (TG) e Termogravimetria Derivada (DTG), onde as curvas de DSC mostraram maior estabilidade térmica para os filmes de amido nativo contendo óleos de mamona e de soja epoxidado, em que foi observada a decomposição térmica entre 270 e 291 o C, sendo mais elevadas que as temperaturas dos demais filmes, além de, quatro estágios de degradação para estes filmes, sendo que os demais obtiveram apenas três estágios de degradação. Filmes de amido nativo com incorporação de 3% de fibras e 2,5% de óleo de soja epoxidado, foram enterrados em solos incubados, para realização do teste de biodegradabilidade, e as análises das emissões do s gases CO 2 , CH 4 e N 2 O foram efetuadas por cromatografia gasosa, onde foi possível observar altas taxas de emissão de CO 2 no primeiro mês de incubação para todos os filmes. Após 90 dias, os filmes foram desenterrados, e a matriz polimérica foi totalmente biodegradada.

Un reacteur a lit fixe et a faible temps de passage a ete utilise pour etudier les principes de la delignification prolongee du procede kraft dans les conditions optimales. En appliquant ces principes (cuisson modifiee), il est possible de fabriquer des pates chimiques de resineux et feuillus d'indices kappa 9-10 et 4-6, respectivement, tout en gardant des proprietes equivalents a celles de pates issues de cuisson conventionnelle. Cependant, la prolongation de la cuisson entraine une perte en hydrates de carbone, ce qui se traduit par une baisse du rendement. Une pate issue de cuisson modifiee presente une aptitude au blanchiment meilleure que celle d'une pate issue de cuisson conventionnelle. Ceci est du a des differences dans la structure de la lignine residuelle qui ont ete etudiees par rmn #1#3c. L'alcalinite plus elevee dans la cuisson conventionnelle conduit a la formation plus importante de structures stables en milieu alcalin qui s'opposent a la degradation ulterieure de la lignine. De plus, la presence de matiere organique dissoute en plus grande quantite dans le cas de la cuisson conventionnelle conduit a la formation de liaisons carbone-carbone qui sont egalement stables. La lignine residuelle d'une pate modifiee, moins affectee par ces reactions, est plus reactive et donc plus facile a eliminer. Enfin, l'application des principes de la delignification prolongee augmente egalement la selectivite d'une delignification soude-anthraquinone. Plusieurs traitements ont ete etudies afin d'ameliorer davantage la cuisson. Un pretraitement avec de la liqueur noire (liqueur en fin de cuisson) augmente la selectivite du procede kraft. Un post-traitement avec le peroxyde d'hydrogene effectue dans le reacteur de cuisson augmente le rendement et baisse l'indice kappa d'une pate par rapport a une cuisson conventionnelle. Un post-traitement avec le sulfite de sodium en milieu alcalin effectue dans le reacteur de cuisson permet de fixer des groupements acides sulfoniques sur la lignine residuelle et d'augmenter ainsi l'aptitude au blanchiment des pates.

Dans la nature les champignons degradent la lignine du bois par l'action de peroxydases. L'une d'elles, la manganese-peroxydase agit par l'intermediaire de l'ion mn#i#i#i sous forme complexe. Dans ce travail nous avons cherche a reproduire l'action de cette enzyme a l'aide de complexes manganiques. La stabilite de ces complexes et leur action sur les monosaccharides, polysaccharides et la lignine ont ete etudiees. Les complexes manganiques sont sans action sur les mono et polysaccharides dans une gamme de ph de 3 a 7. 5. Ce n'est que lorsque le ph est abaisse a 1,5 que les monosaccharides sont oxydes sur la fonction reductrice, dans un mecanisme de decarboxylation. En revanche des composes modeles de la lignine comme la vanilline et une lignine extraite par autohydrolyse flash sont oxydes a ph 4. 5. L'oxydation a ete suivi par evolution des spectres uv et ir, par un test indirect a l'abts. Des experiences de stabilisation de l'ion manganique ont ete conduit par une argile, la montmorillonite acide k#1#0. L'argile ainsi dopee se revele un excellent outil pour l'oxydation de la lignine soluble. Dans une seconde partie de l'etude, l'action des complexes manganiques seuls sur pate kraft de pin provoque une certaine degradation de composes aromatiques et entraine une baisse importante des caracteristiques mecaniques de la pate. Les xylanases, seules, liberent des oligomeres de xylane associes a des fragments de lignine, et provoquent des delaminations importantes aussi bien au sein des pates kraft que dans le bois. La manganese-peroxydase, seule, est incapable d'attaquer la paroi lignocellulosique entiere. Cependant la synergie d'action de xylanases et d'un complexe manganique resulte en une perte de cohesion des fibres accompagnee d'une forte defibrillation due a l'action specifique des ions mn#i#i#i

CAPES
Atualmente há preocupação da sociedade em relação aos impactos gerados pelas indústrias ao meio ambiente. Para produção de celulose e de papel é usada grande quantidade de água, madeira e produtos químicos, sendo gerado efluente nos diferentes processos produtivos da indústria. A matéria orgânica e a cor do efluente do processo Kraft se devem à presença de moléculas derivadas da lignina que são difíceis de serem removidas ou biodegradadas. Com vistas à remedição deste efluente, o presente trabalho busca avaliar a remoção de cor e matéria orgânica residual de efluente de celulose Kraft pré-tratado biologicamente, usando carvão ativado de casca de coco e argila montmorilonita pelo método de adsorção através de delineamentos experimentais. Para remoção de cor e matéria orgânica foram avaliados os fatores: a) pH do efluente; b) massa do material adsorvente no processo de adsorção e c) temperatura. A capacidade de adsorção de matéria orgânica e cor no carvão ativado e argila montmorilonita foram determinados pelo modelo matemático de Langmuir e Freundlich, por meio de ensaios de construção de isotermas de adsorção em efluente Kraft. O efluente foi caracterizado quanto a DQO, DBO5,20, COT e cor verdadeira antes e depois do tratamento terciário. Para o tratamento do efluente foram empregadas duas temperaturas: 25 e 40°C, seguiu-se planejamento fatorial completo 32 em triplicata com ponto central tendo como variáveis pH (5,0; 6,0 e 7,0) e massa de material adsorvente (0,5; 1,0 e 1,5 g). O planejamento experimental utilizado permitiu obter os melhores resultados com carvão ativado em 40 °C, pH 7,0 e 1,5 g de adsorvente com remoção de: 98% de COT, 83% de DQO, 97% de DBO5,20 e 95% de cor verdadeira e para argila em temperatura de 40 oC, pH 7, e 1,5 g de adsorvente com remoção de: 55% de COT, 50% de DQO, 90% de DBO5,20, e 56% de cor verdadeira. A principal variável responsável pela remoção de cor e matéria orgânica foi a massa de adsorvente seguida do pH. Também foi avaliada a possibilidade de aproveitamento do resíduo obtido a partir do processo de adsorção na incorporação de cinzas de carvão na produção de argamassas com teores de 0,4%, 1,0% e 1,2%; em cimento portland, areia e água com tempos de cura de 7 e 28 dias fazendo testes de resistência à compressão. Para a reutilização da argila foram utilizados 15% de argila do processo de adsorção, 25% de vidro e 60% de argila vermelha, para a confecção de corpos de prova cerâmico à temperatura de 1100 oC a 1150 oC. De modo geral, o processo de tratamento proposto neste trabalho utilizando carvão ativado, demostrou ser boa alternativa comparado com argila montmorilonita para redução de cor e matéria orgânica residual do efluente de processo Kraft, tendo-se em vista a utilização da cinza do carvão utilizado no processo de adsorção como um agregado para formação de argamassas na construção civil e argila utilizada na adsorção como material cerâmico.
Nowadays, there is a concern of society regarding the impacts caused by the industries on the environment. Large amounts of water, wood and chemichal are used to produce cellulose and paper, and contaminated effluents are generated through the various industrial processes associated. The organic matter and the color of the Kraft effluent are due to the presence of lignin-derived molecules that are difficult to be removed or biodegraded. With intent to remediate this effluent, this study aim to evaluate the removal of color and residual organic matter from biologically pretreated Kraft effluent, using activated carbon from coconut shell and montmorillonite clay by adsorption method through experimental designs. For the color and organic matter removal, the following factors were evaluated: a) pH of the effluent; b) the mass of the adsorbent material in the adsorption process and c) temperature. The adsorption capacity of organic matter and color in the activated carbon and in the montmorillonite clay were determined by the mathematical model of Langmuir and Freundlich, by means of isotherm adsorption construction in Kraft effluent.The effluent was characterized by COD, DBO5,20, COT and true color before and after the tertiary treatment. For it treatment two temperatures were employed: 25 °C and 40 °C, followed by a 32 full factorial design with center point in triplicate, using pH (5.0, 6.0 and 7.0) and masses of adsorbent material (0.5, 1.0 and 1.5 g) as variables. The experimental design used showed that the best results with activated carbon are obtained at 40 ° C, pH 7.0 and 1.5 g of adsorbent with removals of 98% of TOC, 83% of COD, 97% of BOD5,25 and 95% of true color. With clay, the best results occurred at temperature of 40 ° C, pH 7, and 1.5 g of adsorbent to remove 55% of COT, 50% of COD, 90% of BOD5,20 and 56% of true color. The main responsible for the removal of color and organic matter was the mass of adsorbent, followed by the pH. It was also evaluated the possibility of using the residue obtained from the adsorption process in the incorporation of carbon ash to produce mortars with levels of 0.4%, 1.0% and 1.2% in Portland cement, sand and water, with curing times of 7 and 28 days, for which compressive strength tests were performed. To reuse the clay, 15% of the clay from the adsorption process was used, together with 25% of glass and 60% of red clay, in order to construct ceramics bodies specimen generated at temperatures from 1100 °C to 1150 °C. The treatment process proposed in this work using activated carbon demonstrated to be, in general, a good alternative compared to montmorillonite clay for the color reduction and residual organic matter removal from Kraft process effluent, while residues from both process can be used as aggregates for mortars and ceramic body production.