Orientadores: Luzia Koike, Eugenio Vaz dos Santos Neto / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-19T14:25:27Z (GMT). No. of bitstreams: 1 Fontes_RosaneAlves_D.pdf: 10963624 bytes, checksum: 8162d4b98904d9afe273a093366e9221 (MD5) Previous issue date: 2011 / Neste trabalho foram sintetizados quatro biomarcadores ácidos, a saber: ácido 5b (H) colânico (2), 5a (H) homopregnânico (4), 8,13-tetraidrocopálico (6) e 15-isocopálico (7). Para tanto, foram utilizadas matérias primas comerciais (ácido litocólico e estigmasterol) e o ácido copálico (extraído e purificado a partir de bálsamo de copaíba). Também foi preparado o biomarcador hidrocarboneto 5b (H) colano (8). Estas moléculas foram sintetizadas com o objetivo de serem utilizadas como padrões de referência na quantificação de biomarcadores ácidos e hidrocarbonetos presentes em dois conjuntos de óleos provenientes da Bacia Potiguar. O conjunto I contém cinco óleos de diferentes origens, sendo dois lacustres (LC-1 e LC-2), um marinho evaporítico (ME) e dois mistos (M-1 e M-2) e o conjunto II contém quatro óleos de mesma evolução térmica e mesma origem (ME-a, ME-b, ME-c e ME-d), todos marinho evaporíticos. O que os distingue são os diferentes níveis de biodegradação. Utilizou-se também o isocopalano (9), previamente preparado e cedido pelo Dr. Imamura (2011), na quantificação de biomarcadores terpanos. Os resultados das análises quantitativas dos biomarcadores terpanos e esteranos, quantificados com os padrões de referência 9 e 8, respectivamente, mostraram que quando se utiliza somente o 8 como padrão referência para quantificação de todos os biomarcadores saturados, a quantidade de hopanos fica subestimada em quase 60% quando comparada a quantificação dos mesmos utilizando-se 9. No entanto, isto não significa que este seja um padrão mais adequado a quantificação de todos os terpanos. Quanto às análises dos extratos ácidos de petróleo utilizando-se a técnica de espectrometria de massas seqüencial Trap Linear-Quadrupolo/Orbitrap (LTQ-Orbitrap), observou-se que os resultados foram satisfatórios contribuindo com informações qualitativas úteis para distinção de origem e biodegradação quando relacionadas às distribuições dos ácidos carboxílicos, de acordo com o grau de insaturação destas moléculas. Os perfis moleculares encontrados para os extratos ácidos são muito similares aos que se obtinham com os métodos convencionais de análise de ácidos carboxílicos de petróleo, quando convertidos a ésteres metílicos ou reduzidos a hidrocarbonetos e analisados por CG-EM. A principal vantagem da utilização do Orbitrap na análise qualitativa de ácidos carboxílicos está na redução drástica do tempo de análise atrelada à dispensa de reações de derivatização. Contudo, apesar da altíssima resolução de massas (100.000) o Orbitrap não é capaz de distinguir íons moleculares de estereoisômeros, os quais são altamente difundidos entre os biomarcadores de petróleo. Deste modo, no presente trabalho não foi possível realizar as análises quantitativas dos biomarcadores ácidos. Evidentemente, as técnicas convencionais de análise de biomarcadores ácidos, como CG-EM, permanecem altamente relevantes para estudos geoquímicos. Com relação aos estudos realizados de EM com os padrões de biomarcadores ácidos, sintetizados neste trabalho, foi observado que existe uma correlação direta entre as suas estruturas químicas e os fragmentos gerados a partir da dissociação induzida por colisão dos mesmos. Isto revela o grande potencial desta técnica para obtenção de fragmentos disgnósticos de famílias de biomarcadores ácidos presentes em petróleo a partir da análise direta de extratos ácidos / Four acidic biomarkers were synthesized in this work, namely: 5 b (H) Cholanic acid (2), 5a (H) homopregnanic acid (4), 8, 13-tetrahydrocopalic acid (6) and 15-isocopalic acid (7). For this purpose, were used commercial raw materials (lithocolic acid and stigmasterol) and copalic acid (extracted and purified from copaiba balsam). It was also assembled a hydrocarbon biomaker 5 b (H) Colane (8). These molecules were synthesized in order to be used as reference standards in the quantification of acids and hydrocarbons biomarkers present in two sets of oils from the Potiguar Basin. The set I contains five oils from different sources, two lacustrine (LC-1 and LC-2), a marine evaporitic (ME) and two mixed (M-1 and M-2) and set II contains four oils from the same source (ME-a, ME-b, ME-c and ME-d), all marine evaporitic and the same thermal evolution. What distinguishes them are the biodegradation levels. We also used the isocopalane (9), previously prepared and given by Imamura (2011) in the quantification of terpanes biomarkers. The results of quantitative analysis of terpanes and steranes biomarkers, quantified with reference standards 9 and 8, respectively, showed that when using only the 8 as the reference standard for quantification of all saturated biomarkers, the amount of hopanes is underestimated by almost 60 % when compared to quantification using 9. However, this does not mean that it is a more appropriate standard to quantify all terpanes. Concerning acidic biomarkers analysis using sequential mass spectrometry Linear-Quadrupole/Orbitrap (LTQ-Orbitrap) the results were satisfactory, contributing with qualitative useful information for distinction of origin and the of biodegradation levels. Results are very similar to that obtained with conventional methods of analysis of carboxylic acids from oil, when converted to methyl esters, or reduced to hydrocarbons and analyzed by GC-MS. The main advantage of using the Orbitrap, in the qualitative analysis of acids biomarkers, is the drastic reduction in the time consumed of analysis linked to absence of derivatization reactions. However, despite the very high mass resolution (100,000), Orbitrap is not able to distinguish molecular stereoisomers, which are highly disseminated among the biomarkers of oil. Thus, it was impossible to carry out the quantitative analysis of acidic biomarkers. Of course, conventional techniques of analyses of acidic biomarkers, such as GC-MS, remain highly relevant to geochemical studies. With regard to studies of MS with standard acidic biomarkers, synthesized in this work, the results showed that there is a direct correlation between their chemical structures and fragments generated from the collision induced dissociation. This shows the great potential of this technique to obtain diagnostic fragments of biomarker families present in oils from the direct analysis of acidic extracts / Doutorado / Quimica Organica / Doutor em Ciências

The objectives of this project were to determine the reaction schemes of formanilide and substituted formanilides in acidic and alkaline solutions, to quantiate the kinetics of hydrolysis, to propose reaction mechanisms, and to assess the role of ortho words substitution in formanilide hydrolysis kinetics. A set of thirty substituted formanilides were synthesized and characterized. Hydrolysis of the formanilides was carried out under first order conditions in hydrochloric acid (0.01-8 M, 40°C) and in hydroxide solutions (0.01-3 M, 25°C and 40°C). Hydrolysis kinetics were evaluated in terms of temperature (20°C- 60°C), solvent composition (0-50 % dimethyl sulfoxide, dioxane, ethanol and acetone) and ionic strength (0.1-1) effects. The degradation products were separated and identified using RP-HPLC, and the alkaline and acidic reaction schemes were proposed. For acidic hydrolysis of formanilides, the observed rate constants were proportional to the hydronium concentrations. Modified Hammett plots constructed using the second order rate constants for specific acid catalysis were linear. The ortho effect was analyzed using the Fujita-Nishioka method. In alkaline solutions the observed rate constants showed mixed first and second order dependences with respect to hydroxide concentration. A complex degradation scheme was used to estimate individual rate constants and to construct Hammett plots. Ortho effects were examined for the first order hydroxide concentration dependent pathway. Arrhenius plots for substituted formanilides were linear in both acidic and alkaline media. Ionic strength did not show any effect on the acidic and alkaline hydrolysis rates. In both acidic and alkaline media the rate of hydrolysis decreased with increase in organic solvent content. Formanilide hydrolyzes in acidic solutions by specific acid catalysis and the kinetic study results were consistent with AAC2 mechanism. Ortho substitution led to reduction in rates. The orthoeffect could be split in steric inhibition of resonance, retardation due to steric bulk and through space interactions. In alkaline solutions a complicated kinetic scheme was used to describe the multiple pathways of degradation. The results from the kinetic studies could be explained using a modified BAC2 mechanism. The hydrolysis of meta and parasubstituted formanilides in alkaline conditions did not show substituent effects however ortho substitution led to an decrease in rate constants proportional to the steric bulk of the substituent.

Eukaryotes organize their genomes by wrapping DNA around positively charged proteins called histones to form a structure known as chromatin. This structure is ideal for keeping the genome safe from damage, but also becomes an obstacle for the transcriptional machinery to access information stored in the DNA. To facilitate a balance between storage and accessibility, eukaryotes utilize a family of enzymes known as ATP-dependent chromatin remodelers to directly manipulate chromatin structure. The diverse activities of these chromatin remodeling enzymes range from simply sliding nucleosomes to reveal transcription start sites, to editing the composition of a nucleosome by exchanging canonical histones for histone variants. Chromatin remodeling enzymes recognize features of the nucleosome that activate their ATPase domains and enable proper remodeling function. One nuclear epitope that has been extensively studied is the nucleosomal acidic patch. This negatively charged region on the face of the nucleosome has been shown to be essential for remodeling enzymes like Chd1, ISWI, and INO80C. The chromatin remodeler SWR1C edits nucleosomes by removing the canonical histone H2A from nucleosomes and exchanges it for the histone variant H2A.Z, but the role of the acidic patch in this process has not been investigated. In this work, I showed that SWR1C has normal binding affinity to acidic patch mutant nucleosomes and retains ATPase stimulation but can no longer exchange dimers on this substrate. This work also identified a novel arginine anchor on the essential SWR1C subunit, Swc5, that binds specifically to the nucleosomal acidic patch. The data in this work suggest a mechanism where SWR1C engages nucleosomes and uses the Swc5 subunit to recognize the nucleosomal acidic patch to couple ATPase activity to histone dimer exchange.

Anthropogenic activities such as uranium mining and milling, nuclear weapons production, and nuclear reprocessing have left a legacy of groundwater and soil contaminated with uranium that needs to be addressed. Therefore, developing new remediation technologies to sequester uranium in situ is crucial. The objective of the study was to determine if low-cost commercially available unrefined humic substances, such as Huma-K, can be used to facilitate uranium sorption to minerals in soil and sediment. Sediments from the saturated zone beneath the F-Area seepage basins at the Savannah River Site (SRS) in South Carolina were used for the present study. The SRS site is analogous to many contaminated locations where groundwater acidity enhances uranium and other contaminants mobility. First, a variety of techniques were applied to characterize Huma-K and SRS sediment. Characterization studies showed that Huma-K possesses functional groups that have an acidic nature such as carboxyl and phenol groups. For SRS sediment, a mineral composition of mainly quartz (93.2%), kaolinite (5.1%), and goethite (1.1%) was identified. Second, the interactions between Huma-K and SRS sediment were investigated through batch experiments. Sorption, homogeneous precipitation, and surfaced-induced precipitation were observed to be enhanced at pH 4. However, Huma-K removal from solution decreased with an increase of pH. The sorption behavior was not able to be described by any of the models employed (pseudo-first, pseudo-second, Langmuir, and Freundlich). Third, the interactions between uranium and SRS sediment with and without Huma-K amendment were investigated. In acidic conditions (pH 3-5), the sorption capacity of SRS sediment amended with Huma-K was significantly increased compared to plain sediment. At circumneutral conditions, uranium removal from solution decreased for SRS sediment amended with Huma-K, compared with plain sediments, likely as a result of the formation of aqueous uranium-humic complexes. In summary, the results from the present study suggest that Huma-K, and likely other unrefined humate products, has the characteristics and effects necessary to be suitable for subsurface injection to remediate uranium in acidic groundwater conditions. The treatment zone will persist as long as the pH does not increase sufficiently to cause soil-bound Huma-K to be released, remobilizing uranium.

京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第20430号 / 農博第2215号 / 新制||農||1048(附属図書館) / 学位論文||H29||N5051(農学部図書室) / 京都大学大学院農学研究科食品生物科学専攻 / (主査)教授 谷 史人, 教授 安達 修二, 教授 松村 康生 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM

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The chenistry of diamino dicarboxylic acids together with that of monoamino dicarboxylie and monocarboxylic acids in of great importance to the chemist because of the rolation- ship of these compounds to the biochemistry of cancer. Diamino dicarboxylic acids in general, contain two asymmetric carbon atoms and may exist in one optically inactive and two optically active forma. Alpha-omoga diamino pinolic acid is the only member of the alpha-omoga diamino dicarboxylic acids thus far known to occur naturally.

No description available.

The final goal of this study is to establish a microscale analysis method that allows solution phase characterization of interactions between β2-glycoprotein I (β2gpI) and some of its ligands. Human β2gpI is a phospholipid- and heparin-binding plasma glycoprotein. The physiological role of the protein in normal blood coagulation is not entirely known, nor is its role in autoimmune diseases characterized by blood clotting disturbances (thrombosis). Quantitative binding data of β2gpI interactions with some of its ligands may help elucidating the mechanisms behind these diseases and in the development of new approaches for diagnostics, prevention, and therapy. In this thesis, capillary electrophoresis (CE) was used as methodological platform for the interaction studies. The analysis of peptides and proteins by CE is desirable due to low sample consumption, possibilities for non-denaturing and highly effective separations. The first objective of this thesis was to find an approach to prevent charge dependent adsorption of β2gpI to the inner surface of the capillaries. Analyte adsorption at the negatively charged inner surface of fused silica capillaries is detrimental to interaction analyses. This phenomenon is especially pronounced in the analysis of basic proteins and proteins containing exposed positively charged domains, such as β2gpI. A new strategy to suppress these solute-wall interactions was devised, investigated and optimized. This strategy exploits the pH hysteresis behavior of fused silica surfaces, by simply performing an acidic pretreatment of the capillary. The results in this thesis show that the acidic pretreatment efficiently prevents protein adsorption. / <p>Papper 4 Estimation of the amount of β₂-glycoprotein I adsorbed at the inner surface of fused silica capillaries after acidic, neutral and alkaline pretreatment ingick som manuskript i avhandlingen, nu publicerad.</p>

This study shows how the composition of gases released from a single magmatic source may be modified during their ascending path. The main processes that influence the composition of the gases in these high temperature fumarolic environments, are: 1) interactions with wallrocks during gas ascent, which change the fugacities of the metal volatile species and affect the equilibrium between major species (fH2S/fSO2; fH2/fH2O); 2) mixing with meteoric water with consequent Cl adsorption, which may account for the Cl depletion of the gases; 3) remobilisation of previously formed sublimates and/or incrustation deposits. Comparison between the thermochemical models and the mineralogical composition of the silica tubes at Kudryavy and Satsuma-Iwojima volcanoes suggests that high fO2 due to the mixing of the gases with air during their injection into the atmosphere significantly reduces the volatility of several trace elements (As, Sb, Sn, Na, K, Tl, Te, Se and Cd). Comparisons between the enriched metals in aerosols and in the gases suggest that Mo, Pb, Bi, Na, K, Cu, Zn or Fe, which are enriched in the gases, are preferentially deposited in the gas conduits and vents whereas the highly volatile metals (Te, Tl, Sb, As and Se) and Cd condense in the plume. This study determines the reactions that may occur during the alteration of rocks in high temperature fumarolic environments. Three different processes of alteration prevail: (1) Acidic alteration which is characterized by the complete absence of clays, because the constant supply of gases to these systems allows for the pH values of the acidic fluids to be maintained low enough to prevent the precipitation of clay minerals. Complete leaching of all cations, except Si, from the primary silicates leads to important "silicification" of the wall rock. The primary mineral cations are leached in the following order: K, Na > Ca > Fe, Mg > Al > Si, Ti. The fluids enriched in these cations circulate in microcracks at different temperatures and different redox conditions and lead to the precipitation of secondary incrustations. At Kudryavy the incrustations are mainly sulfates. At Usu the lower sulfur/fluoride ratio of the gases allows the occurrence of aluminum fluoride incrustations. The order of primary minerals dissolution (olivine > plagioclase > pyroxene > matrix glass > Fe-Ti oxides) is established for both sites studied. (2) Alteration by an oxidized volcanic gas, resulting from mixing with the atmosphere (500 to 300°C). At Kudryavy, thermochemical modeling suggests that anhydrite and anhydrous sulfates, which occur at intermediate temperatures, are formed by interactions of the rock with oxidized gas. (3) The most important outcome of this work is the identification of the features of alteration by the volcanic gas that directly reacts with the rock at high temperatures (T > 500°C). The Kudryavy rocks show evidences for mineral transformations, which occur in the presence of the volcanic gas phase. Volcanic gas directly reacts with rocks at high temperatures (T > 500°C). The gas destabilizes the primary minerals, remobilizes the rock-bearing cations, and leads to the formation of second mineral assemblages. These transformations occur in situ, without significant mobility (gain or loss) of the cations. The high temperature secondary associations are characterized by the presence of andradite, hedenbergite, hercynite, tridymite/cristobalite. Anhydrite and anhydrous Al sulfate may occur within these mineral assemblages if the gas is oxidized.