Thesis (M.Med.Sc.)--University of Western Australia, 2004.

Ruthenium, proposed as a new candidate of diffusion barrier, has three different kinds of oxides, which are native oxide, electrochemical reversible oxide and electrochemical irreversible oxide. Native oxide was formed by naturally exposed to air. Electrochemical reversible oxide was formed at lower anodic potential region, and irreversible oxides were formed at higher anodic potential region. In this study, we were focusing on the effect of copper electrodeposition on each type of oxides. From decreased charge of anodic stripping peaks and underpotential deposition (UPD) waves in cyclic voltammetry (CV), efficiency of Cu deposition dropped off indicating that interfacial binding strength between Cu and Ru oxides was weakened when the Ru surface was covered with irreversible oxide and native oxide. Also, Cu UPD was hindered by both O2 and H2 plasma modified Ru surfaces because the binding strength between Cu and Ru was weakened by O2 and H2 plasma treatment. Cu/Ru and Cu/Ta bimetallic corrosion was studied for understanding the corrosion behavior between diffusion barrier (Ta and Ru) and Cu interconnects under the post chemical mechanical planarization (CMP) process in semiconductor fabrication. Gallic acid is used in post CMP slurry solution and is known well as antioxidant which is supposed to oxidize itself to prevent other species from oxidizing. However, in this study under the observation of Cu microdot corrosion test, copper was corroded only in gallic acid at specific pH region of alkaline condition which is close to the pH region for post CMP solution formula. With different pH alkaline condition, gallic acid formed different oxidized products which are characterized by cyclic voltammetry and UV-Vis spectroscopy. Therefore, the specific oxidized product from particular pH region condition caused the Cu corrosion. Also, the corrosion rate of Cu microdots was influenced by substrate effect (Cu/Ru and Cu/Ta) and ambient control, which was included in this study.

It was hypothesized that ester-linked gallic acid glycosides could be absorbed and metabolized in vivo due to the instability of an ester-linked glycosides at neutral pH. To evaluate in vivo absorption of Mangifera Indica, L. var. Keitt polyphenolics, it was first necessary to chemically characterize the compounds present using HPLC-MSn analysis. Mango pulp and extracts were also incubated with a pectinase, cellulase, pectinase with ß-glucosidase activity, and a pure ß-glucosidase to learn the extent of hydrolysis with potential application to enhancing bioavailability as a result of incubation to increase mango juice yield. After which the same extracts were assessed in differentiated Caco-2 cells to discern stability at physiological pH and to characterize metabolite formation in vitro. Finally, human urinary metabolites were characterized after 10 day consumption of 400 g in 11 individuals. Mass spectroscopic characterization and HPLC quantification of mango pulp revealed for the first time two monogalloyl glucosides (MGGs) with distinct differences in their glycoside linkages, with the ester form dominating, as well as the presence of five other phenolic acid glycosides; hydroxybenzoic acid glucoside, courmaric glucoside, ferulic acid glucoside, and sinapic acid mono and di-glucosides. Six oxygenated carotenoid derivatives were identified for the first time in a phytochemical extract, namely, a phytohormone, abscisic acid and its glycoside, two catabolism products of abscisic acid, dihydrophasic acids, and two hydroxy-dimethyl decadiene-dioic acid glucopiranosylesters. Gallotannins ranging from tetra-galloyl glucosides to nona-galloyl glucosides were also identified in the pulp, but not quantified. Clearzyme 200XL and Rapidase AR2000 were the most effective at increasing juice yield of mango pulp due to their pectinase action. Cz reduced the amount of ester-linked MGG by 70% after 4 hours of incubation while Rap hydrolyzed the ether linked MGG. The instability of ester-linked galloyl-glycosides at pH 7.4 was characterized by HPLC-MS and after only four hours of incubation a shift from HWM tannins (>8GG) to LMW (<8GG) occurred and resulted in 25 mg/L free gallic acid. Caco-2 cells metabolized gallic acid, MGG from a mango extract, and a gallotannin extract into O-methyl gallic acid indicating catechol-O-methyl transferase (COMT) as a major metabolizing enzyme for gallic acid. Urinary metabolites were identified by HPLC-MSn in dependant scans. O-methylgallic acid-O-sulfate was identified as the major metabolite 0-6 hours post consumption, followed by O-methylgallic acid at a lower concentration. The presence of gallic acid metabolites in the urine indicates absorption of ester-linked glycosides. Colonic metabolites were detected beginning 3-6 hours after consumption of mango, and were identified as pyrogalloyl derivatives. They are hypothesized to be the products of microbial breakdown of gallotannins. Daily consumption of mango for 10 days increased the concentration of O-methylgallic acid-O-sulfate, but was not significant.

Thesis (M. S.)--University of North Texas, Aug., 2007. / Title from title page display. Includes bibliographical references.

Made available in DSpace on 2014-06-11T19:25:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-06-22Bitstream added on 2014-06-13T18:26:25Z : No. of bitstreams: 1 silva_acap_me_arafcf.pdf: 700931 bytes, checksum: 859de3c2d6bc2ff9e78faf746b707164 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / Paracoccidioides brasiliensis e P. lutzii são fungos dimórficos, agentes etiológicos da paracoccidioidomicose, que é uma micose humana sistêmica geograficamente confinada na América Latina. Vários antifúngicos podem ser utilizados para o tratamento dessa doença, tais como anfotericina B, sulfamídicos e azólicos (itraconazol) e de maneira geral seu uso é prolongado. As limitações frequentes dos antifúngicos e o aumento na incidência das infecções fúngicas sistêmicas têm ressaltado a necessidade da descoberta e do desenvolvimento de novos fármacos. O objetivo deste estudo foi comparar a atividade antifúngica de anfotericina B, itraconazol e galatos de alquila anti-complexo de Paracoccidioides por métodos fenotípicos e proteômicos. Para tanto foi padronizado o teste de sensibilidade para selecionar o galato de maior potência, utilizando o documento M27-A2 (2002), modificado pela adição de Alamar Blue. Adicionalmente, análises proteômicas foram realizadas antes e após tratamento com o antifúngico selecionado para verificar o perfil das possíveis proteínas-alvo. A atividade antifúngica foi estudada contra isolados de P. brasiliensis (S1, S2 e PS3) e P. lutzii, (Pb01-like), e depois o teste foi estendido para mais seis isolados. O valor da CIM do ácido gálico variou de 31,25 a 0,250 mg/L para todos os isolados. Os galatos mostraram valores de CIM entre 16 a 0,004 mg/L. O menor valor de CIM foi observado para seis galatos que possuem uma substituição por uma cadeia relativamente longa de carbonos. O perfil proteico dos isolados Pl01 e Pb18 foi estudado por eletroforese 2D após contato com anfotericina B , itraconazol e o galato de decila (todos a uma concentração de 0,125 mg/L. Mais de 130 spots para ambos os fungos foram observados e a maioria destas proteínas... / Paracoccidioides brasiliensis and P. lutzii are dimorphic fungi, etiological agents of paracoccidioidomycosis, which is a systemic human mycosis geographically restricted to Latin America. Various antifungal agents may be used to treat this disease, such as amphotericin B, sulfamidic agents and itraconazole, and these drugs are used in long-term therapies. The limitations of antifungals and increased incidence of systemic fungal infections has underscored the need for discovery and development of new drugs. The objective of this study was to compare the antifungal activity of amphotericin B, itraconazole and alkyl gallates anti-Paracoccidioides complex by phenotypic and proteomic methods. Thus, the susceptibility test was applied to select the most potent gallate, using the document M27-A2 (2002), modified by the addition of Alamar Blue. Finally, proteomic analyses was developed before and after the treatment with the antifungal agent selected, to study the protein profile after this treatment. The antifungal activity was evaluated against isolates of P. brasiliensis (S1, S2 and PS3) and P. lutzii (PB01-like), and after, the test has been extended to six isolates. The MIC values of gallic acid varied from 31.25 to 0.250 mg/L for all isolates. The gallates showed MIC values ranging from 16 to 0,004 mg/L. The lowest MIC value was observed for six gallates bearing a substitution for a long side chain. The protein profile of isolates Pb18 and Pl01 was studied by 2D electrophoresis after contact with amphotericin B, itraconazole and decyl gallate, all in the concentration of (0.125 mg/L ). More than 130 spots for both species were observed, and the most of these proteins... (Complete abstract click electronic access below)

Made available in DSpace on 2014-06-11T19:23:05Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-08-25Bitstream added on 2014-06-13T20:29:47Z : No. of bitstreams: 1 barbosa_vf_me_arafcf.pdf: 526140 bytes, checksum: 50d8a074a37389b25908e0fd537d9859 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Compostos fenólicos são conhecidos por possuírem propriedades antioxidantes que influenciam na qualidade dos alimentos. O ácido gálico e seus derivados apresentam propriedades antioxidantes, antimicrobiana e propriedades antimutagênicas. Neste trabalho avaliamos a ação desses compostos sobre processos oxidativos in vitro e ex vivo sendo: i) Modelos químicos na supressão de formas oxidantes de ABTS +, DPPH HOCl, H2O2, O2 -, NO e taurina cloramina; ii) Sistemas enzimáticos como HRP e MPO; iii) Sistemas celulares com polimorfonucleares e eritrócitos frente a AAPH e HOCl. Os ensaios envolvendo as espécies oxidativas na presença de ácido gálico e derivados mostraram uma boa inibição, sendo que a amostras triacetato de ácido gálico mostrou ser a melhor das amostras testadas. Em relação aos sistemas enzimáticos os dados indicam inibição não competitiva ou mista. Nos sistemas celulares foi observado: i) citotoxicidade frente às células eritrocitárias e aos polimorfonucleares, ii) a amostra galato de isopropila demonstrou menor citotoxicidade frente aos eritrócitos, iii) a amostra galato de butila foi a que apresentou relativamente menor citotoxicidade chegando a 80% de morte celular, e iv) as outras amostras chegavam a 100% de morte celular na mesma concentração. Pelos dados obtidos, concluiu-se que o ácido gálico e seus derivados são potentes antioxidantes e inibidores das peroxidases HRP (Horseradish peroxidase) e MPO (mieloperoxidase), e com alta citotoxidade frente aos sistemas celulares estudados / Phenolic compounds are known to have antioxidant properties that influence the quality of food. Gallic acid and its derivatives have antioxidant, antimicrobial and antimutagenic properties. In this study the action of these compounds on oxidative processes in vitro and ex vivo which: i) Models in the suppression of chemical forms of oxidizing ABTS•+, DPPH• HOCl, H2O2, O2 •-, NO• and taurine chloramine ii) Enzymatic systems HRP and MPO iii) cellular systems with polymorphonuclear cells and erythrocytes against AAPH and HOCl. Tests involving the oxidative species in the presence of gallic acid and its derivatives showed good inhibition, and the triacetate samples of gallic acid were found to be the best of the tested samples. Regarding enzyme systems data indicate non-competitive or mixed inhibition. In cellular systems were observed: i) cytotoxicity against cells to erythrocyte and polymorphonuclear ii) the sample with erythrocytes the isopropyl gallate showed less cytotoxicity compared to the others samples, iii) the sample of butyl gallate showed the relatively lower cytotoxicity reaching 80% of cell death, and iv) the other specimens came to 100% cell death at the same concentration. From the data obtained showed that the gallic acid and its derivatives are potent antioxidants and inhibitors of peroxidases HRP (horseradish peroxidase) and MPO (myeloperoxidase), and high cytotoxicity against the cell systems studied

Resumo: Compostos fenólicos são conhecidos por possuírem propriedades antioxidantes que influenciam na qualidade dos alimentos. O ácido gálico e seus derivados apresentam propriedades antioxidantes, antimicrobiana e propriedades antimutagênicas. Neste trabalho avaliamos a ação desses compostos sobre processos oxidativos in vitro e ex vivo sendo: i) Modelos químicos na supressão de formas oxidantes de ABTS +, DPPH HOCl, H2O2, O2 -, NO e taurina cloramina; ii) Sistemas enzimáticos como HRP e MPO; iii) Sistemas celulares com polimorfonucleares e eritrócitos frente a AAPH e HOCl. Os ensaios envolvendo as espécies oxidativas na presença de ácido gálico e derivados mostraram uma boa inibição, sendo que a amostras triacetato de ácido gálico mostrou ser a melhor das amostras testadas. Em relação aos sistemas enzimáticos os dados indicam inibição não competitiva ou mista. Nos sistemas celulares foi observado: i) citotoxicidade frente às células eritrocitárias e aos polimorfonucleares, ii) a amostra galato de isopropila demonstrou menor citotoxicidade frente aos eritrócitos, iii) a amostra galato de butila foi a que apresentou relativamente menor citotoxicidade chegando a 80% de morte celular, e iv) as outras amostras chegavam a 100% de morte celular na mesma concentração. Pelos dados obtidos, concluiu-se que o ácido gálico e seus derivados são potentes antioxidantes e inibidores das peroxidases HRP (Horseradish peroxidase) e MPO (mieloperoxidase), e com alta citotoxidade frente aos sistemas celulares estudados / Abstract: Phenolic compounds are known to have antioxidant properties that influence the quality of food. Gallic acid and its derivatives have antioxidant, antimicrobial and antimutagenic properties. In this study the action of these compounds on oxidative processes in vitro and ex vivo which: i) Models in the suppression of chemical forms of oxidizing ABTS•+, DPPH• HOCl, H2O2, O2 •-, NO• and taurine chloramine ii) Enzymatic systems HRP and MPO iii) cellular systems with polymorphonuclear cells and erythrocytes against AAPH and HOCl. Tests involving the oxidative species in the presence of gallic acid and its derivatives showed good inhibition, and the triacetate samples of gallic acid were found to be the best of the tested samples. Regarding enzyme systems data indicate non-competitive or mixed inhibition. In cellular systems were observed: i) cytotoxicity against cells to erythrocyte and polymorphonuclear ii) the sample with erythrocytes the isopropyl gallate showed less cytotoxicity compared to the others samples, iii) the sample of butyl gallate showed the relatively lower cytotoxicity reaching 80% of cell death, and iv) the other specimens came to 100% cell death at the same concentration. From the data obtained showed that the gallic acid and its derivatives are potent antioxidants and inhibitors of peroxidases HRP (horseradish peroxidase) and MPO (myeloperoxidase), and high cytotoxicity against the cell systems studied / Orientador: Olga Maria Mascarenhas Farias Oliveira / Coorientador: Iguatemy Lourenço Brunetti / Banca: Maria José Queiroz de Freitas Alves / Banca: José Carlos Rebuglio Vellosa / Mestre

Tea and coffee are rich in polyphenols with a variety of biological activities. Polyphenols found in tea are predominantly flavonoids, of which up to 15% are present as free or esterified gallic acid. Coffee polyphenols are almost wholly comprised of chlorogenic acids. Many of the demonstrated activities of polyphenols are consistent with favourable effects on the risk of chronic diseases. In investigating the relationships between intake and exposure to such compounds and chronic disease-related endpoints, it is important to be able to identify biomarkers that are specific to the compounds of interest. 4-O-methyl gallic acid (4OMGA) and isoferulic acid have been identified as potential biomarkers of intake and exposure to polyphenols derived from tea and coffee, respectively. 4OMGA is derived from gallic acid in tea, and isoferulic acid from chlorogenic acid in coffee. The major objectives of the research which is the subject of this thesis were (1) to establish a dose-response relationship of 24h urinary excretions of 4OMGA and isoferulic acid following ingestions of black tea and coffee of different strengths, and (2) to explore relationships of tea and coffee intake with 24h urinary excretion of 4OMGA and isoferulic acid in human populations. It was found that there was rapid excretion of both 4OMGA and isoferulic acid in the first 6h after tea and coffee ingestion, respectively. Approximately 60 80% of the ingested dose was excreted during the first 6h after ingestion. Urinary excretion of 4OMGA and isoferulic acid was directly related to the dose of tea and coffee, respectively. That is, higher intake resulted in increased urinary excretion of the metabolites. The relationships of 24h urinary excretion of 4OMGA and isoferulic acid with long-term usual (111 participants) and contemporary recorded current (344 participants) tea and coffee intake were assessed. 4OMGA was strongly related to usual (r = 0.50, P < 0.001) and current (r = 0.57, P < 0.001) tea intake. Isoferulic acid was less strongly, but significantly associated with usual (r = 0.26, P = 0.008) and current (r = 0.18, P < 0.001) coffee intake. Overall, the results are consistent with the proposal that 4OMGA is a good biomarker for black tea derived polyphenol intake and exposure, but isoferulic acid may have only limited use as a biomarker for coffee-derived polyphenol exposure.

Orientador: Marcos Antônio Correa / Resumo: A busca por ativos naturais que apresentem mais de uma função em uma única formulação é pautada em um novo conceito de praticidade e economia, estando em acordo com a visão crítica do consumidor moderno. Neste contexto, a presença dos compostos fenólicos em plantas tem sido estudada por estes apresentarem diversas atividades farmacológicas e cosméticas. Os ácidos hidroxibenzoicos fazem parte desse grupo de compostos orgânicos, sendo o ácido gálico um de seus representantes, conhecido principalmente por sua atividade antioxidante. Um grande número de formulações tópicas contendo antioxidantes tem sido lançado nos últimos anos. O objetivo deste trabalho foi estudar a eficácia do ácido gálico para uso cosmético. Para escolha dos solventes utilizados no estudo levou-se em consideração o desenvolvimento sustentável da pesquisa, ou seja a utilização de solventes verdes. Para a avaliação da atividade antioxidante foram utilizados dois métodos diferentes o DPPH e o ABTS. Também foi realizada a avaliação das atividades despigmentantes, antimicrobiana, citotóxica, bem como estudos da formulação desenvolvida, como: estabilidade, liberação, permeação e retenção, através de experimentos in vitro. Os resultados demonstram que o ácido gálico é um potente antioxidante, suas ações despigmentante e antimicrobiana também foram comprovadas. Pelos estudos de citotoxidade in vitro pode-se constatar que a porcentagem de ácido gálico utilizada na emulsão desenvolvida é segura. A validação da metodol... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The search for natural assets that present more than one function in a single formulation is based on a new concept of practicality and economy, being in agreement with the critical view of the modern consumer. In this context, the presence of phenolic compounds in plants has been studied because they present several pharmacological and cosmetic activities. Hydroxybenzoic acids are part of this group of organic compounds, and gallic acid is one of its representatives, known mainly for its antioxidant activity. A large number of topical formulations containing antioxidants have been launched in recent years. The objective of this work was to study the efficacy of gallic acid for cosmetic use. To choose the solvents used in the study took into consideration the sustainable development of the research, ie the use of green solvents. For the evaluation of the antioxidant activity, two different methods were used: DPPH and ABTS. The evaluation of depigmenting activities, antimicrobial, cytotoxic, as well as studies of the developed formulation, such as: stability, release, permeation and retention, were carried out through in vitro experiments. The results demonstrate that gallic acid is a potent antioxidant, its depigmenting and antimicrobial actions have also been proven. By in vitro cytotoxicity studies it can be verified that the percentage of gallic acid used in the developed emulsion is safe. The validation of the methodology by HPLC ensured all parameters necessary for the s... (Complete abstract click electronic access below) / Mestre

Os processos fibrogênicos, ativados por mecanismos como estresse oxidativo, podem levar a um quadro de cirrose hepática, que representa uma das principais causas de morte no ocidente. Entretanto, em alguns estudos, substâncias fenólicas, como o Ácido Gálico (AG), demonstraram inibir e até regredir esses processos. O objetivo do presente estudo foi investigar os efeitos do composto fenólico AG no processo fibrogênico hepático murino. Os mesmos foram avaliados tanto na fase de progressão da fibrose, como na cirrose hepática estabelecida pela administração crônica de tetracloreto de carbono em camundongos C57. Para isso foram realizadas análises histológicas, imuno-histoquímicas, PCR e Western-bloting, estimando-se fatores relacionados à fibrogênese e mediadores inflamatórios associados. Observou-se uma diminuição importante na percentagem de áreas coradas pelo Sirius red, ou seja, redução na percentagem de fibrose nos grupos tratados com AG, tanto durante a prevenção (p<0,05), quanto na regressão da cirrose (p<0,05). Esta melhora foi acompanhada de redução no número de células marcadas pela SMA nos grupos tratados (p<0,05). Estes mesmos parâmetros foram confirmados através da análise genômica para colágeno, assim como pelo TIMP e pelo TGF 1; e proteômica para NFB e p38 MAPK. Os achados do presente estudo demonstraram o efeito do AG sobre a prevenção e reversão do processo fibrogênico hepático. Os principais mecanismos deste processo envolvem atividades anti-inflamatórias via TGF-1 e p38 MAPK, principalmente durante a indução de fibrose; assim como restrição da capacidade anti-apoptótica do NFB sobre as células estreladas hepáticas (CEH) na cirrose já estabelecida. / The fibrogenic processes activate by mechanisms such as oxidative stress can lead to a picture of liver cirrhosis, which represents a major cause of death in West. However, in some studies, phenolic substances, such as Gallic Acid (GA) shown to inhibit and even regress theses processes. The aim of this study was to investigate the effects of the phenolic compound GA in murine liver fibrogenic process. They were evaluated both in progression of fibrosis and in liver cirrhosis established by administration carbon tetrachloride im mice C57. For this, was performed histological, immunohistochemical, PCR and Western blotting analysis, estimating factors related to fibrogenesis and inflammatory mediators associated. There was a significant decrease of area stained by Sirius Red, which means reduction in the percentage of fibrosis in the groups treated with GA. Both for prevention (p<0,05) and for the regression of the cirrhosis (p<0,05). This improvement was accompanied by a reduction in the number of cells marked by SMA in the treated groups (p<0,05). These parameters was confirmed by genomic analysis for collagen, as well as by TIMP 1 and TGF 1, and proteomics for p38 MPK and NFkB. The findings of this study demonstrade the effect of GA in the prevention and of liver fibrogenic process. The main mechanisms of this process involves anti-inflammatory activity via TGF 1 and p38 MAPK, especially during induction of fibrosis, as well as restriction of antiapoptotic capacity of NFkB on the CEH in established cirrhosis.