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Towards an Understanding of Dissolved Organic Matter Molecular Composition and Reactivity in the EnvironmentCottrell, Barbara 07 January 2014 (has links)
Dissolved organic matter (DOM), one of the most complex naturally occurring mixtures, plays a central role in the biogeochemistry and the photochemistry of natural waters. A complete understanding of the environmental role of DOM will come only from the elucidation of the relationship between its structure and function. This thesis presents new work on the separation, characterization, and reactivity of DOM in rainwater, freshwater, and seawater. A new separation technique based on counterbalance capillary electrophoresis was developed for the separation of Suwannee River NOM. A comparative study of the organic content of rainwater was accomplished using nuclear magnetic resonance (NMR) with spectral database matching ,Fourier transform ion cyclotron mass spectrometry (FT-ICR-MS), and comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (GCxGC-TOFMS). Three complementary, non-overlapping datasets identified of over 400 compounds. Analysis of the FT-ICR-MS data using van Krevelen diagrams and the carbon oxidation state showed variation in the elemental composition and molecular size. Over 50% of the compounds identified in this study were known components of secondary organic aerosol (SOA) and volatile organic carbon (VOCs). Dissolved organic matter (DOM) plays a central role in the photochemistry of natural waters through the production of reactive oxygen species and the triplet excited state of DOM (3DOM*). These reactive species are central to the reactivity, transport, and fate of both natural and anthropogenic chemicals in the environment. Laser flash photolysis (LFP) was used to demonstrate that particulate organic matter (POM) generates a triplet excited state species (3POM*). LFP of seawater from the Pacific Ocean and the Bermuda Atlantic Time Series Station detected similar excited state species from surface to 4535m. Metal speciation has been implicated in the photochemistry of natural waters. Copper immobilized metal affinity chromatography (IMAC) of seawater and freshwater isolated a low and a high affinity fraction that generated excited state transients. Excitation-emission matrix spectroscopy showed that while the seawater fractions were autochthonous, freshwater fractions enriched in chromophoric DOM (CDOM), were allochthonous. The discovery of these different classes of compounds in freshwater and seawater has important implications both for the mineralization of DOM and the removal of xenobiotics in the aquatic environment.
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The Study of Molecular Composition of Dissolved Organic Matter in Two Different Ecosystems: Inle Lake and Bago Mountains in Myanmar / 2つの異なる生態系における溶存有機物質の分子組成に関する研究: ミャンマー, インレー湖およびバゴ山地Tint, May Thet Su Kyaw 23 January 2023 (has links)
京都大学 / 新制・課程博士 / 博士(農学) / 甲第24325号 / 農博第2530号 / 新制||農||1096(附属図書館) / 学位論文||R5||N5427(農学部図書室) / 京都大学大学院農学研究科森林科学専攻 / (主査)教授 德地 直子, 教授 柴田 昌三, 教授 舘野 隆之輔 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DGAM
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Étude des COV issus de la dégradation thermique et oxydative des matériaux polymères / Study of VOC emitted by thermal and oxidative degradation of polymeric materialsLatappy, Hubert 10 July 2014 (has links)
Les matériaux polymères sont aujourd'hui très présents dans notre environnement et deviennent irremplaçables pour de nombreuses applications : emballage, textile, mobilier,... La connaissance du cycle de vie de ces matériaux, de la production à leur destruction, devient importante pour nos sociétés. Par exemple ces matériaux peuvent émettre des Composés Organiques Volatils qui sont souvent toxiques et leur impact sur le milieu doit être évalué. L’objectif de ce travail de thèse a été de développer une méthode au laboratoire pour identifier et quantifier ces émissions. La difficulté provient de la grande diversité des composés qui peuvent être émis. Par ailleurs la méthode nécessite une fréquence de mesure élevée (temps réel) souvent incompatible avec les techniques actuelles. Une solution analytique couplant un four et un spectromètre de masse haute résolution associé à une méthode d’ionisation chimique contrôlée a été développée. Celle-ci est basée sur un spectromètre FT-ICR compact à bas champ magnétique : BTrap. Les points forts de cette technique sont la très haute résolution en masse qui permet de mesurer la masse exacte des composés et la détection multi composés, simultanée sur toute la gamme de masse. L’ionisation chimique contrôlée permet l'ionisation douce et quantitative des molécules d’intérêt. Le transfert de proton à partir de l’ion H₃O⁺ (PTRMS) a montré son potentiel pour la détection des COV dans de nombreux domaines. Après une présentation du contexte et du besoin, le dispositif expérimental développé est détaillé. La validation de celui-ci pour l'analyse de gaz traces a été effectuée au LPGP, sur un système de dépollution par plasma froid. Les résultats de dégradation de l'acétaldéhyde en fonction des conditions de fonctionnement du réacteur sont présentés.L’ionisation par PTR conduit habituellement à la molécule protonée ce qui simplifie l’identification. Cependant des fragmentations peuvent être observées. L’utilisation d’un précurseur d’ionisation chimique plus lourd et moins réactif que H₃O⁺ pourrait minimiser ces phénomènes. L’utilisation du diflurobenzène protoné a été testée et comparée à celle de l’ion H₃O⁺. Pour cela, des études cinétiques ont été menées sur une série d’alcools connus pour fragmenter avec H₃O⁺, et confirment l'intérêt du nouveau précurseur.Le poly(méthacrylate de méthyle) (PMMA) est un matériau très répandu : plexiglass. Sa dégradation est a priori relativement simple puisqu’il s’agit très majoritairement d’une dépolymérisation, accompagnée de la formation de produits minoritaires. En conséquence, son étude nous a paru intéressante pour la mise au point et la validation de la méthode. La dégradation du PMMA a été étudiée sous atmosphère inerte, puis oxydante. Les résultats obtenus sont présentés : produits émis, bilan en masse, et apport du suivi en temps réel de la dégradation, montrant en particulier que les produits minoritaires sont émis après le monomère.Enfin une dernière partie de conclusion présente les perspectives pour cette nouvelle méthode. / Polymeric materials are now ubiquitous in our environment and become irreplaceable for many applications such as packaging, textile or furniture. Knowledge of the life cycle of these materials from production to destruction becomes important for our societies. For instance, plastics may release Volatile Organic Compounds: VOCs are often toxic and their impact on the environment must be evaluated. The aim of this thesis work is the development of a laboratory method for identification and quantification of these emissions. The difficulty arises from the wide variety of compounds being potentially emitted. Moreover the desired method requires a high measurement rate ("real time") often incompatible with existing techniques. An analytical device coupling a furnace and a high-resolution mass spectrometer associated with a controlled chemical ionization method has been developed. This device is based on a low magnetic field FT-ICR compact mass spectrometer. The strengths of this technique are (i) high mass resolution allowing exact mass measurements, (ii) recording of the whole mass range simultaneously, allowing detection of a large variety of compounds. Controlled chemical ionization allows soft and quantitative ionization of molecules of interest. Proton transfer from H₃O⁺ ion (PTRMS) has shown its potentialities for VOC detection in many areas. After presenting the background and need, the developed experimental device is described in detail.The validation of this instrument for trace gas analysis has been performed at LPGP, using a nonthermal plasma depollution device. The results of acetaldehyde degradation according to operating conditions in the discharge reactor are presented.PTR ionization usually leads to the protonated molecule, so that identification is simplified. However fragmentations are sometimes observed. Use of a chemical ionization precursor ion heavier and less reactive than H₃O⁺ may minimize these drawbacks. Protonated difluorobenzene was selected as a precursor and its reactivity was tested and compared with H3O+ reactivity. In this purpose, kinetic studies were performed on a series of alcohols known for their fragmentation behavior with H₃O⁺. The results confirm the interest of the new precursor.Polymethyl methacrylate (PMMA) is a widespread material: plexiglass. Its degradation process is relatively simple since it consists in predominant depolymerization, along with formation of minor products. Consequently, PMMA study appeared interesting for method development and validation. Thermal degradation of PMMA has been studied under inert, then oxidative atmosphere conditions. The presented results include identification of minor products and mass balance under different temperature conditions. Real-time monitoring of VOC emission showed time differences in emission peaks of MMA monomer and minor products, each of them being emitted slightly later than MMA. Finally, a conclusive part presents the perspectives opened for this new method.
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Développement de méthodes séparatives pour la caractérisation d’une glycoprotéine intacte : application à l’hormone chorionique gonadotrophine humaine / Development of separation methods for the characterization of a glycoprotein at the intact level : application to the human chorionic gonadotropin hormoneCamperi, Julien 08 November 2018 (has links)
La glycosylation est la forme la plus courante de modification post-traductionnelle (PTM) des protéines humaines, puisque plus de 70% d’entre elles sont glycosylées. Celle-ci régule de nombreuses propriétés biologiques comme leur stabilité, leur demi-vie et leur activité. Néanmoins, les protéines peuvent également présenter d'autres types de PTM, ce qui peut conduire pour une protéine donnée à un très grand nombre d'isoformes variant par leur masse, leurs propriétés biologiques et physico-chimiques et leur concentration dans les échantillons biologiques. Ainsi, caractériser une glycoprotéine comporte de nombreux défis et nécessite la mise en œuvre de méthodes séparatives très performantes et de détection très sensibles et informatives.La gonadotrophine chorionique humaine (hCG) est l’hormone spécifique de la grossesse humaine. Elle est essentielle au développement du placenta et du fœtus. Elle est composée de deux sous-unités hCGα et hCGβ qui sont fortement glycosylées (4 sites de N-glycosylation et 4 sites d’O-glycosylation). Récemment, des travaux ont montré une corrélation entre sa glycosylation et une bonne implantation du fœtus. Une caractérisation des ces glycoformes s’avère donc nécessaire.Par conséquent, de nouvelles méthodes en LC/CE-MS ont été développées pour la caractérisation de la hCG à l’échelle intacte en utilisant deux médicaments à base de hCG ayant des glycosylations différentes. Alors que la méthode en CZE-MS (TQ) a permis de différencier les profils des glycoformes de la sous-unité hCGα des deux médicaments, la complémentarité des méthodes RP- et HILIC-MS (qTOF) a conduit à leur identification.Pour limiter les erreurs potentielles d’identification dues au chevauchement des profils isotopiques, le profil de chaque isoforme a été résolu par FT-ICR MS. Dans ce but, une séparation au format nanoLC en mode RP a été développée, améliorant ainsi la sensibilité de la méthode d’un facteur 500 par rapport au format conventionnel. Cette méthode a permis de confirmer l’identification des glycoformes de la sous-unité hCGα. D’autre part, il a été possible d’obtenir des profils différents de glycosylation de la sous-unité hCGβ en favorisant leur ionisation par réduction de la hCG. Enfin, un traitement à la PNGase a conduit à l’élimination des N-glycanes pour l’obtention des profils d’O-glycosylation de la sous-unité hCGβ. / Glycosylation is the most common form of post-translational modifications (PTMs) of human proteins, since more than 70% are glycosylated. It regulates numerous biological properties including their stability, half-life, and activity. Nevertheless, proteins can also exhibit other types of PTMs that lead to a very large number of isoforms, varying in mass, properties and concentration in the biological samples. Therefore, the characterization of a glycoprotein is highly challenging and requires the use of powerful separation techniques and sensitive and informative detection modes.The human chorionic gonadotropin (hCG) is the hormone specific to human pregnancy. It is essential for the development of placenta and fetus. It is based on two heavily glycosylated subunits, hCGα and hCGβ, having 8 glycosylation sites (4 N- and 4 O-glycosylation sites). Some recent studies demonstrated that here is a correlation between the hCG glycosylation state and the fetus implantation. This is why the characterization of the hCG glycoformes is needed.Therefore, new LC/CE-MS methods were developed for the characterisation of hCG at the intact level using two hCG-based drugs having different glycosylation profiles. While the CZE-MS (TQ) method showed its potential for glycosylation fingerprinting, the complementarity of LC-(qTOF) MS methods in RP and HILIC modes allowed the identification of the glycoforms of the hCGα subunit.To limit the identification errors due to the overlapping of isotopic distribution patterns, the profile of each isoform was resolved by FT-ICR MS. For this purpose, a nanoLC separation in RP mode was developed, thus improving the sensitivity of the method by a factor 500 compared to the conventional format. This method allowed the confirmation of the identification of hCGα glycoforms. Then, it was possible to obtain different glycosylation patterns of the hCGβ by promoting its ionization after hCG reduction. Then, a PNGase treatment was carried out to remove the N-glycans in order to obtain the O-glycoprofiles of hCGβ isoforms.
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Etude des interactions levures/bactérie par métabolomique / A metabolomic study of yeast/bacteria interactionsLiu, Youzhong 24 November 2015 (has links)
Le vin en tant qu’écosystème complexe est un modèle particulièrement intéressant pour l’étudie des interactions entre les microorganismes. L’interaction sans contact celluaire (interaction indirecte) entre la levure Saccharomyces cerevisae et la bactérie lactique Oenococcus oeni a un effect direct sur l’induction et l'achèvement de la fermentation malolactique (FML), une fermentation très importante pour la qualité du vin. Une souche levurienne peut être classée FML+ si elle stimule la croissance bactérienne et FML- si elle a un effet inhibiteur. Les métabolites connus qui inhibent ou stimulent la FML ne permettent pas toujours d’expliquer cette distinction phénotypique. Dans ce travail de thèse, nous avon développé un workflow multidisciplinaire qui combine l’approche métabolomique non ciblée, l’analyse classique ciblée, les statistiques et les réseaux. L’objectif premier était de dévoiler des métabolites levuriens impliqués dans l’interaction entre levures et bactéries par une comparaison directe des exométabolome des deux phénotypes.À cet effet et pour la première fois dans l’éude d’interactions inter-espèces, la Spectrométrie de Masse à Résonance Cyclotronique des Ions et à Transformée de Fourier (FT-ICR-MS) et la Chromatographie Liquide couplée à la Spectrométrie de Masses (UPLC-Q-TOF-MS) ont été combinées. Pour mieux visualiser les données à haut débit générées par les deux plate-formes, une méthode statistique non supervisée MetICA a été developpée et validée. Par rapport à l’analyse en composantes principales (ACP), cette nouvelle méthode peut réduire la dimension des données d'une façon plus robuste et fiable. Afin d’extraire des métabolites impliquées dans la distinction phénotypique, nous avons comparé différentes methodes de classification et choisi la meilleure pour chaque jeu de données. Les structures putatives de ces biomarqueurs ont été validés par la spectrométrie de masse MS/MS et leurs rôles physiologiques sur la croissance bactérienne ont été confirmées in vitro. La découverte de biomarqueurs a été complétée par l’analyse ciblée réalisées par Chromatographie en Phase Liquide à Haute Performance (HPLC). La complémentarité entre les différentes techniques métabolomiques a conduit à l’identification de nouveaux biomarqueurs de familles distinctes, comme des composés phénoliques, des sucres, des nucléotides, des acides aminés et des peptides. En outre , l'analyse des réseaux métaboliques a révélé des liens entre les biomarqueurs de levure et a suggéré des voies bactériennes influencés par l’exo-métabolome de levure.Notre workflow multidisciplinaire a révélé une réelle capacité à identifier des signatures moléculaires nouvelles et inattendues de l’interaction levure-bactérie. / As a complex microbial ecosystem, wine is a particularly interesting model for studying interactions between microorganisms. Contact-independent interactions (indirect interactions) between the yeast Saccharomyces cerevisae and the lactic acid bacterium Oenococcus oeni have a direct effect on malolactic fermentation (MLF), induction and completion, which is an important factor in wine quality. Yeast strains could be classified as MLF+ phenotype if it usually stimulates the bacterial growth or MLF- in the opposite case. The known metabolites that stimulate or inhibit the MLF cannot always explain the phenotypic distinction. In this work, a multidisciplinary workflow combining non-targeted metabolomics, targeted analysis, statistics and network was developed. The main objective was to unravel diverse yeast metabolites involved in yeast-bacteria interaction via a direct comparison of exo-metabolomes of MLF+ and MLF- phenotypes.To that purpose, and for the first time in the research of interspecies microbial interactions, two metabolomics platforms, Fourier Transform Ion Cyclotron Resonance -Mass Spectrometry (FT-ICR-MS) and Liquid Chromatography coupled with Mass Spectrometry (UPLC-Q-TOF-MS) were used in combination. To better visualize the high-throughput data generated from the two platforms, a novel unsupervised statistical method, the MetICA was developed and validated. Compared to classical principal component analysis (PCA), the new method reduced the data dimension in a more robust and reliable way. To extract metabolic features involved in the phenotypic distinction, we have compared different statistical classifiers and selected the best one for each dataset. Putative structures of these biomarkers were validated via MS/MS fragmentation analysis and their physiological roles to bacteria were confirmed in vitro. The discovery of biomarkers was complemented by targeted HPLC (high performance liquid chromatography) analysis. The complementarities between different analytical techniques led to new biomarkers of distinct chemical families, such as phenolic compounds, carbohydrates, nucleotides, amino acids and peptides. Furthermore, metabolic network analysis has revealed connections between yeast biomarkers and suggested bacterial pathways influenced by yeast exo-metabolome.Our multidisciplinary workflow has shown its ability to find new and unexpected molecular evidence of wine yeast-bacteria interaction.
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Aplicações da Espectrometria de Massas de Ressonância Ciclotrônica de Íons por Transformada de Fourier (FT-ICR MS) em PetroleômicaPereira, Thieres Magaive Costa 23 August 2013 (has links)
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Previous issue date: 2013-08-23 / O petróleo é uma mistura complexa, sendo uma das misturas mais desafiadoras para as análises químicas. Muitas técnicas são empregadas para a caracterização dos constituintes do óleo. Entretanto, quando combinamos o altíssimo poder de resolução e exatidão da espectrometria de massas, em especial a Ressonância Ciclotrônica de Íons com Transformada de Fourier, (FT-ICR MS) com fontes de ionização a pressão atmosférica, uma atribuição precisa de mais de 20 000 compostos orgânicos do petróleo pode ser obtida. Na indústria do petróleo existe um grande interesse na análise de ácidos naftênicos e asfaltenos devido a problemas como corrosão e formação de depósitos, que aumentam os custos de produção. Portanto este trabalho tem como objetivo a avaliação da termodegradação de ácidos naftênicos, além do emprego das fontes de ESI, APCI, APPI, LDI e MALDI para aquisição de novos dados relativos a caracterização de asfaltenos. Dois petróleos foram utilizados nos ensaios de termodegradação, o petróleo A com acidez de 2,38 mg KOH g-1 e o petróleo B com 4,79 mg KOH g-1 os quais foram tratados a 280, 300 e 350 ºC pelo período de 2, 4 e 6 horas. De uma maneira geral, as principais classes identificadas para ambas às amostras foram O2, N e NO2, respectivamente. Uma leve redução do NAT e da abundância relativa referente à classe O2 foram observado em função da temperatura e do tempo de envelhecimento (T = 280 → 300 oC e t = 2 → 6 h), sendo que a temperatura de tratamento térmico a 350 ºC demonstrou-se determinante na remoção de compostos da classe O2. O perfil químico de amostras de asfaltenos brasileiros foi avaliado utilizando-se cinco diferentes métodos de ionização em ambos os modos de ionização: positivo e negativo, depois, a distribuição de peso molecular, distribuição de classe, parcelas típicas de número de carbono contra DBE e diagramas van Krevelen foram obtidos e discutidos. Um comportamento atípico foi observado para a fonte de LDI e MALDI (±) FT-ICR MS. Um amplo perfil, de m/z 500-3000, apresentando espaçamento de 24 Da foi observado, e este corresponde a formas alotrópicas de fulereno, C60. Em geral, os asfaltenos apresentaram um elevada proporção de espécies heteroatómicas como: HC, HC [H], N, N [H], N2O, N2O [H], N2, N2 [H], O, O[H] para o modo (+) e N, N [H], NO, NO [H], NO, NO2[H], N2O, N2O[H] para o modo negativo. Nos diagramas de DBE contra o número de carbono, os asfaltenos mostraram para cada valor de DBE uma pequena amplitude de compostos com respeito à NC, proporcionando assim, imagens que formam uma linha de 45 ° entre os eixos CN e DBE. Isto indica que estes compostos não exibem grandes cadeias de alquílicas, sendo composta principalmente por anéis aromáticos. Em geral os diagramas de van Krevelen mostraram alta proporção de compostos com razão H/C ~0,7, corroborando com a existência de espécies altamente aromáticas / Petroleum is a complex mixture, being one of the most challenging mixtures for chemical analyzes. Many techniques are employed to characterize constituents of the oil. However , when we combine the highest resolving power and accuracy of mass spectrometry , especially Ion Cyclotron Resonance Fourier Transform ( FT - ICR MS ) with sources of atmospheric pressure ionization , an assignment need more than 20 000 organic compounds in the oil can be obtained. In the oil industry there is a great interest in the analysis of asphaltenes and naphthenic acids due to problems such as corrosion and deposit formation, which increases production costs. Therefore this study aims to evaluate the thermodegradation of naphthenic acids, besides the use of sources of ESI, APCI, APPI, MALDI and LDI for the acquisition of new data on the characterization of asphaltenes . Two test oils were used in thermodegradation of the oil with an acidity of 2.38 mg KOH g -1 and Oil B with 4.79 mg KOH g- 1 which were treated at 280 , 300 and 350 ° C for a period of 2 , 4 and 6 hours. Generally, the major classes identified for both samples O2, NO2, and C, respectively. A slight reduction of NAT and relative abundance refers to the class O2 were observed as a function of temperature and aging time (T = 280 → 300 ° C t = 2 → 6 h), and the heat treatment temperature at 350 ° C showed a determinant for the removal of class O2. The chemical asphaltenes Brazilian samples was evaluated using five different methods of ionization in both modes of ionization: positive and negative, then the molecular weight distribution, distribution class, typical plots versus carbon number and DBE van Krevelen diagrams were obtained and discussed. An unusual behavior was observed for the LDI and MALDI source ( ± ) FT - ICR MS . A comprehensive profile of m / z 500-3000, with spacing of 24 Da was observed, and this corresponds to allotropes of fullerene C60. In general, the asphaltenes had an heteroatómicas high proportion of species such as HC , HC [ H] , N, [ H] , N2O N2O [ H] N2, N2 [ M ] O O [ H] to mode (+) and N, [ H ] , NO [ H] , NO , NO2, [ H] , N2O N2O [ H ] for the negative mode . In the diagrams DBE against the carbon number , the asphaltenes shown for each value of DBE composed of a small amplitude with respect to NC, thus providing images that form a line of 45 ° between the axes CN and DBE. This indicates that these compounds do not exhibit large chain alkyl, composed mainly of aromatic rings. In general diagrams van Krevelen showed a high proportion of compounds ratio H / C ~ 0.7, confirming the existence of highly aromatic species
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Oleorresina de Copaifera spp.: caracterização, verificação da atividade antimicrobiana in vitro e avaliação preliminar de uma formulação em vacas leiteiras com mastite / Oleoresin of Copaifera spp.:characterization, verification antimicrobial activity in vitro and preliminary evaluation a formulationFaria, Maria Juíva Marques de 07 May 2014 (has links)
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Dissertação - Maria Juíva Marques de Faria - 2014.pdf: 3781718 bytes, checksum: 5a98e4c3d48dde6e80b58427a1a73012 (MD5)
Previous issue date: 2014-05-07 / Bovine mastitis is an inflammatory/infectious process of the mammary gland, its etiology is complex and multivariate. The most common mastitis has bacterial origin. Because of the high cost to treat this disease, and the bacterial resistance to antibiotics, beyond the losses due to the milk discard or the presence of drug residues in milk, studies are necessary to find out alternative methods to circumvent these problematic. The medicinal plants with antimicrobial activity have been making room in veterinary medicine with the objective to reduce the impact and the use of drugs indiscriminately, as well as maintain the integrity of the animal and control the dissemination of resistant bacterial lineage. Therefore, the aim of this work was characterize the oleoresin Copaifera spp., verify the antimicrobial activity in vitro of oleoresin and essential oil of Copaifera spp. in combating against aerobic and facultative isolated bacteria from cows’ milk with subclinical grade III mastitis diagnostic and evaluate preliminarily, in vivo, phytotherapic formulation composed of Copaifera spp. The tests for characterization of the oleoresin, confirmed its authenticity and quality, considered appropriate for use. The analyzes performed by gas chromatography coupled to mass spectrometry (GC/MS) and electrospray ionization Fourier transformed íonic cyclotron resonance mass spectrometry (ESI FT-ICR MS) identified sesquiterpenes and diterpenes present in the essential oil and oleoresin of Copaifera spp., respectively. The technique of High Performance Liquid Chromatography (HPLC) for sesquiterpenes, especially for β-caryophyllene, can be used in quality control of essential oil and oleoresin of Copaifera spp., as well as in phytotherapic formulation using oleoresin of Copaifera spp. The oleoresin showed better antimicrobial activity than the essential oil of Copaifera spp. (ρ<0,0001) in combating the 55 isolated bacteria. The antibiogram test of the three phytotherapic formulations demonstrated that the oleoresin had antimicrobial activity against the isolated microorganisms. The preliminary evaluation, in vivo, of a phytotherapic formulation containing 20% oleoresin of copaiba was neither effective nor safe, because it intensified the inflammatory process, requiring further tests, such as cytotoxicity and irritability of the raw material plant and of the vehicle used.
Key words: Bovine Mastitis. Oleoresin. Essential Oil. Copaifera spp. Minimum Inhibitory Concentration. ESI FT-ICR MS. / Mastite bovina é um processo inflamatório/infeccioso da glândula mamária, de etiologia complexa e multivariada, sendo a de origem bacteriana a mais frequente. Devido aos elevados custos dos tratamentos dessa enfermidade, resistência bacteriana aos antibióticos, além dos prejuízos inerentes ao descarte do leite ou à presença de resíduos de medicamentos no mesmo, faz-se necessário estudos que busquem métodos alternativos para contornar essa problemática. As plantas medicinais com potencial antimicrobiano vêm ganhando espaço na medicina veterinária com o objetivo de reduzir o impacto e o uso de medicamentos de forma indiscriminada, bem como manter a integridade do animal e controlar a disseminação de linhagens bacterianas resistentes. Diante disso, o objetivo desse trabalho foi caracterizar a oleorresina de Copaifera spp., verificar atividade antimicrobiana in vitro da oleorresina e do óleo essencial de Copaifera spp. frente às bactérias aeróbias e facultativas isoladas de leite de vacas diagnosticadas com mastite subclínica grau III e avaliar preliminarmente, in vivo, formulação fitoterápica à base de Copaifera spp. Os testes de caracterização da oleorresina de Copaifera spp. demonstraram sua autenticidade e qualidade, a qual foi considerada adequada para o uso. As análises realizadas por cromatografia gasosa acoplada à espectrometria de massas (CG/EM) e por espectrometria de massas com ionização por electrospray de ressonância ciclotrônica de íons por transformada de Fourier (ESI FT-ICR MS) identificaram os sesquiterpenos e diterpenos presentes no óleo essencial e na oleorresina de Copaifera spp., respectivamente. A técnica Cromatografia Líquida de Alta Eficiência (CLAE) para sesquiterpenos, em especial para β-cariofileno, pode ser utilizada no controle de qualidade de oleorresina e óleo essencial de Copaifera spp., bem como em formulação fitoterápica utilizando oleorresina de Copaifera spp. como matéria-prima vegetal. A oleorresina apresentou melhor atividade antimicrobiana do que o óleo essencial de Copaifera spp. (ρ<0,0001) frente às 55 bactérias isoladas. O teste de antibiograma das três formulações fitoterápicas demonstrou que a oleorresina de copaíba reproduziu a sua atividade antimicrobiana frente aos micro-organismos isolados. A avaliação preliminar, in vivo, de uma formulação fitoterápica contendo 20% oleorresina de copaíba não foi eficaz e nem segura, pois intensificou o processo inflamatório, havendo necessidade de testes futuros, como de citotoxicidade e de irritabilidade dessa matéria-prima vegetal e do veículo utilizado.
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Estendendo a caracterização dos compostos nitrogenados em resíduo de vácuo por FT-ICR MS / Extending the characterization of nitrogen compounds in vacuum residue by FT-ICR MSVasconcelos, Géssica Adriana 10 March 2016 (has links)
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Previous issue date: 2016-03-10 / Outro / Petroleomics by FT-ICR MS was able to characterize petroleum and its derivatives at molecular level. The most used ionization source on the analysis of these compounds is electrospray. However, species that are more basic or more acidic suppress the ionization of other compounds with less strength. This disadvantage consists of, especially in positive mode, only detecting compounds with higher pKa values preventing the mass spectrometer from reading less basic species that is also present in the sample. In view of this, the development of new methods whose purpose is to minimize these effects is essential. An alternative is to use fast techniques of extraction and separation followed by analysis by FT-ICR MS. This study pursued two goals: first, to perform an extraction of vacuum residue into basic and neutral nitrogen compounds using different methods, and second, to fractionate the basic nitrogen compounds present in RV according to their mass/ratio. Three methods were tested to achieve the first objective: solvent extraction (LLE), column chromatography (LC), and solid phase extraction (SPE). The results showed that LLE was the less selective technique among all three studied procedures. SPE and LC showed similar results, and they allowed to partially separate the basic nitrogen compounds from neutral species. To accomplish the second goal, a fractionation using SPE was applied to the vacuum residue sample. This procedure permitted to detect compounds that apparently were not present in the untreated sample as a consequence of a reduction on ion suppression effect. Electrospray ionization and high resolution mass spectrometry (FT-ICR MS) were employed on the analysis of each sample. / A petroleômica por FT-ICR MS foi capaz de caracterizar o petróleo e seus diferentes derivados a nível molecular. A fonte de ionização mais utilizada na análise destes compostos é o electrospray. Componentes mais básicos e mais ácidos, entretanto, suprimem a ionização de outras espécies com menor força. A grande desvantagem deste fato consiste, especialmente no modo positivo, detectar somente os compostos com elevado pKa impedindo a leitura das espécies menos básicas presentes na mesma amostra. À vista disso, é fundamental o desenvolvimento de novos métodos que tenham por finalidade minimizar estes efeitos. Uma alternativa é fazer o uso de técnicas rápidas de extração e separação seguida pelas análises por FT- ICR MS. Desta forma, este estudo teve dois objetivos principais: primeiro, realizar uma extração dos compostos nitrogenados de resíduo de vácuo em suas frações básica e neutra utilizando diferentes métodos e, segundo realizar um fracionamento dos compostos nitrogenados básicos presentes em RV de acordo com a sua massa. Para se alcançar o primeiro objetivo, três métodos foram testados: Extração líquido-líquido (LLE), cromatografia em coluna clássica (LC) e extração em fase sólida (SPE). Os resultados mostraram que o LLE foi a menos seletiva dentre os três procedimentos estudados. SPE e LC apresentaram resultados semelhantes e foi possível separar parcialmente os compostos básicos das espécies neutras. Para alcançar o segundo objetivo, um fracionamento utilizando extração em fase sólida foi empregado na amostra de resíduo de vácuo. Este procedimento permitiu detectar compostos que aparentemente não estavam presentes na amostra não tratada como consequência da redução do efeito de supressão iônica. A ionização por electrospray e por espectrometria de massa de alta resolução (FT-ICR MS) foram utilizados na análise de cada amostra.
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Condensed tannin characterization with FT-ICR MALDI mass spectrometry and separation with saw-tooth gradient HPLCReeves, Savanah Gail 03 June 2020 (has links)
No description available.
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Vliv kovalentně vázané fluorescenční značky na strukturu a funkci proteinů / Effect of binding of a fluorescent label on the protein structure and functionPetrovová, Gabriela January 2013 (has links)
Fluorescent labeling is a method used for visualization of various types of biomolecules including proteins and protein complexes. However, the effect of protein labeling on protein structure and functions has not been investigated so far. The goal of the diploma thesis was to examine an influence of NHS-fluorescein binding on structure and function of human carbonic anhydrase I (hCA-I). The particular aims of this work were to prepare recombinant 15N-hCA-I which was used for NMR structure analysis of carbonic anhydrase upon fluorescent labeling. Furthermore, enzyme activity was measured in order to find out a correlation between the concentration of NHS- fluorescein and protein function. In addition, the reaction mixtures were systematically analyzed by ESI FT-ICR mass spectrometry. The analysis revealed experimental conditions for fluorescent labeling of human carbonic anhydrase I with minimal effect on protein structure and function. The results of this study show that the calculation of molar excess of NHS-fluorescein cannot rely on a simple procedure provided by manufacturer. However, due to decrease of enzyme activity upon fluorescent labeling, it is better to take into count the influence of NHS-fluorescein concentration on the relative enzymatic activity. Moreover, the calculation of molar...
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