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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Estudo de eficácia e segurança (citotoxicidade) do ácido gálico incorporado a um sistema emulsionado. /

Custodio, Alessandra Aparecida Cruz. January 2019 (has links)
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
12

Efeito do Ácido Gálico sobre a fibrogênese hepática murina / Effect of Gallic Acid in murine hepatic fibrogenesis

Figueiredo, Sergio Souza 13 April 2012 (has links)
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.
13

Desenvolvimento de uma formulação de uso intracanal com atividade antimicrobiana obtida a partir de uma planta do semiárido brasileiro / Development of a formulation of use intra root with antimicrobial activity got from a plant of brazilian semi-arid

Brandão, Deysiane Oliveira 17 February 2014 (has links)
Submitted by Jean Medeiros (jeanletras@uepb.edu.br) on 2016-03-02T18:19:59Z No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) PDF - Deysiane Oliveira Brandão.pdf: 3147875 bytes, checksum: 4e032a8ddfe55546168a4cf23c724b4c (MD5) / Approved for entry into archive by Secta BC (secta.csu.bc@uepb.edu.br) on 2016-06-13T20:33:36Z (GMT) No. of bitstreams: 2 PDF - Deysiane Oliveira Brandão.pdf: 3147875 bytes, checksum: 4e032a8ddfe55546168a4cf23c724b4c (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2016-06-13T20:37:48Z (GMT). No. of bitstreams: 2 PDF - Deysiane Oliveira Brandão.pdf: 3147875 bytes, checksum: 4e032a8ddfe55546168a4cf23c724b4c (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2014-02-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Due to the absence of a fully effective intracanal formulation, the search for new drugs from medicinal plants is necessary.In this case the Ximenia americana L., stink plant widely used in traditional medicine as antibacterial, may be used develop new formulations intracanal. However, there is no standardization of their extract by the pharmaceutical industry, with regard to studies of pre-formulation and standardization of analytical techniques to determine its safety, efficacy and quality. In this context, this study aimed to develop from X. americana L. one intracanal paste , with antimicrobial activity, applying parameters validation process for testing and microbiological potency determination of major chemical component, toxicological studies and drug excipient compatibility. Two types of extracts were obtained from the bark of X. American L, hydroalcoholic which was subsequently sprayed in spray dryer and that ethanol extract was concentrated on a rotary evaporator. For determination of antimicrobial activity, used the hidroalcólicos extracts applying the technique of agar / cylinder diffusion. Toxicological tests consisted in acute toxicity and cytotoxicity. Phytochemical analysis was based on quantitative determination of total polyphenols, total flavonoids, tannins condensed and total saponins. The major chemical compound was identified as gallic acid by high performance liquid chromatography efficiency as well as its determination, which was validated according to the official compendia. The validation of microbiological assay was performed X. American compared to standard (gallic acid). The study drug / excipient compatibility was accomplished by applying analytical techniques and term spectroscopy in the infrared region. X. American, showed activity against Staphylococcus aureus, Enterococcus faecalis, Streptococcus oralis and Klebsiella pneumoniae. As biosecurity, this plant showed no toxicity in the assays analyzed. Phytochemical analysis showed good concentrations of secondary metabolites. The marker was identified and quantified in the concentration of 12μg/mL. Regarding the microbiological assay, this presented, linearity, accuracy, precision, limits of detection and quantification and robustness. As for the compatibility study excipients that were incompatible in thermoanalytical techniques, spectroscopy, these incompatibilities were not as intense, with respect to removal of functional groups of excipients and the dry extract. Thus studies that show the development of a herbal medicine, as well as the characterization and standardization of the extract of X. American L are important because lack of official methodology that proves the quality, safety and efficacy of these products. / Devido a ausência de uma formulação intracanal totalmente eficaz, é necessária a pesquisa de novas medicações a partir de plantas medicinais. Nesse caso a Ximenia americana L., planta da catinga, amplamente utilizada pela medicina tradicional como antibacteriano, pode ser indicada para desenvolvimento de formulações intracanais. Todavia, não existe uma padronização do seu extrato pela indústria farmacêutica, no que diz respeito a estudos de préformulação e padronização de técnicas analíticas para determinação de sua segurança, eficácia e qualidade. Nesse contexto, com esse estudo pretendeu desenvolver a partir de X. americana L. uma pasta intracanal, com atividade antimicrobiana, aplicando parâmetros de validação de processo para os ensaios de potencia microbiológica, doseamento do componente químico majoritário, estudos toxicológicos e de compatibilidade fármaco excipiente. Foram obtidos dois tipos de extratos a partir da casca de X. americana L, hidroalcóolicos que posteriormente foi selecionado nebulizado em spray dryer e extrato etánolico que foi concentrado em evaporador rotativo. Para determinação, da atividade antimicrobiana, utilizou os extratos hidroalcólicos aplicando a técnica de difusão ágar/cilindros. Os ensaios toxicológicos consistiram na determinação da toxicidade aguda e citotoxicidade. A análise fitoquímica foi baseada na determinação quantitativa de polifenóis totais, flavonoides totais, taninos condensados e saponinas totais. O composto químico majoritário foi identificado como ácido gálico através da cromatografia líquida de alta eficiência, assim como seu doseamento, o qual foi validado de acordo com os compêndios oficiais. Foi realizado o processo de validação do doseamento microbiológico da X. americana em relação ao padrão (ácido gálico). O estudo de compatibilidade fármaco/excipiente foi realizado aplicando técnicas termo analíticas e espectroscopia na região do infravermelho. X. americana L, apresentou atividade contra Staphilococcus aureus, Enterococcus faecalis, Streptococcus oralis e Klebsiella pneumoniae. Quanto a segurança biológica, essa planta não apresentou toxicidade nos ensaios analisados. A análise fitoquímica demonstrou níveis aceitáveis de concentrações de metábólitos secundários. O marcador foi identificado e quantificado na concentração de 12µg/mL. Quanto ao doseamento microbiológico, esse apresentou linearidade, precisão exatidão, limites de detecção e quantificação e robustez dentro das especificações. Quanto ao estudo de compatibilidade os excipientes que foram incompatíveis nas técnicas termoanalíticas, na espectroscopia essas incompatibilidades não foram tão intensas, no que respeito a supressão de grupos funcionais dos excipientes e do extrato seco. Assim estudos que mostrem o desenvolvimento de um medicamento fitoterápico, bem como a caracterização e padronização do extrato de X. americana L\ são importantes, devido falta de metodologia oficial que comprove a qualidade, segurança e eficácia de destes produtos.
14

Efeito do Ácido Gálico sobre a fibrogênese hepática murina / Effect of Gallic Acid in murine hepatic fibrogenesis

Sergio Souza Figueiredo 13 April 2012 (has links)
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.
15

Subcritical water extraction of functional ingredients and glycoalkaloids from potato peel

Singh, Pushp 06 1900 (has links)
Potato peel, a waste generated from potato processing is a disposal problem. But, it is a good source of phenolic compounds, sugars, and glycoalkaloids. This study examines the subcritical water extraction of phenolics, glycoalkaloids and sugars from potato peel and compares it to conventional solvent extraction. Experiments were conducted in a batch stainless steel reactor at 6 MPa, 2 mL/min and 100 to 240C for 30-120 min. The results revealed that highest recoveries of phenolic compounds (81.23 mg/100 g; fw) and sugars (75 mg/g; fw) were obtained using subcritical water at 180C and 30 min and at 160C and 120 min, respectively. Low content of glycoalkaloids (1.19 mg/100 g, fw) was obtained using subcritical water. The yields of phenolics and sugars using subcritical water were 40 and 45% higher than using a conventional solvent extraction method. Therefore, subcritical water might be a good substitute to organic solvents such as methanol and ethanol to obtain functional ingredients from potato peel. / Food Science and Technology
16

Antioxidant Distribution and Effectiveness in a Model Muscle System

Ballesteros, Ann Theodore 01 February 2009 (has links)
Gallic acid esters (GAE) of varying alkyl chain length were used to determine how antioxidant physical location and partitioning influence hemoglobin-catalyzed lipid oxidation. Specific GAE used were propyl gallate (PG), octyl gallate (OG), and lauryl gallate (LG). GAE partitioning experiments were performed with either isolated cod muscle membranes or washed cod muscle, which primarily contain polar membrane lipids and myofibrillar proteins. Canola oil was used in some experiments to determine how neutral lipids impact partitioning behavior. GAE distribution was determined spectrophotometrically in the recovered membranes, aqueous phase, and oil layer after employing differential centrifugation. Oxidation was monitored by measuring thiobarbituric acid reactive substances (TBARS) and lipid hydroperoxides development.When GAE were added to the membrane suspensions, significant differences (p < 0.05) in GAE partitioning were observed in the aqueous phase and membrane sediment, where increases in GAE alkyl chain length corresponded with a decrease in aqueous phase concentrations and increases in the membranes. GAE partitioning in the oil fraction did not show significant differences. Also, increases in GAE alkyl chain correlated with increases in GAE membrane detection when GAE were added to the washed fish muscle (p < 0.05).Adding GAE to the washed cod muscle before the canola oil was the most effective sequence of addition for extending the storage time before lipid oxidation was detected. Among the three GAE tested, PG showed the greatest inhibition against lipid oxidation. The effectiveness of the GAE in the washed cod-canola oil system follows the order, PG > OG > LG, which corresponds with decreasing hydrophobicity.The conclusions of this study are twofold. First, GAE partitioning into the muscle membranes was not the primary factor for delaying the onset of lipid oxidation. Rather, solubility in the aqueous phase showed the greatest impact on extending storage time. Secondly, the order in which GAE and canola oil were added to the washed cod (WC) muscle system influenced hemoglobin-catalyzed lipid oxidation behavior. Adding GAE before the neutral oil may have allowed the GAE to partition more easily into the polar regions of the washed muscle, which in turn provided the most effective protection against oxidation.
17

The Effects Of Hydrogen Peroxide, Gallic Acid And Resveratrol On Growth And Catalase Production Of Aspergillus Fumigatus

Dogan, Tunca 01 February 2008 (has links) (PDF)
The aim of this study was to analyze the effect of hydrogen peroxide and selected phenolic compounds on growth and catalase production of Aspergillus fumigatus. As a result of growing A. fumigatus at different temperatures it was observed that, growth and catalase production of this species were highest at 37 &deg / C. Catalase production was highest in the presence of 1 mM H2O2, yielding a significant 3 fold increase with respect to the control. Biomass was also increased by 1,44 fold with respect to the control sample. H2O2 increased catalase production possibly by inducing oxidative stress as biomass production significantly increased after the depletion of H2O2. Both gallic acid and trans-resveratrol significantly enhanced biomass generation of A. fumigatus (1,17 fold increase at 10 mM gallic acid and 1,45 fold increase at 3 mM resveratrol with respect to controls) and decreased extracellular catalase production (4,33 fold at 25 mM gallic acid and 16,7 fold decrease at 3 mM resveratrol with respect to controls) especially in the first 5 or 6 days of the cultivation where the anti-oxidant activity of the compounds were possibly at their maximum. A sudden and significant rise was observed in extracellular catalase activity between 5th and 7th days of the cultivation in phenolic compound applied samples, possibly owing to the depletion of the antioxidant activity of gallic acid and resveratrol followed by fungal cells&rsquo / response to a sudden increase of oxidative stress by boosting catalase production.
18

Subcritical water extraction of functional ingredients and glycoalkaloids from potato peel

Singh, Pushp Unknown Date
No description available.
19

Military Religio: Caesar's Religiosity Vindicated by Warfare

Adkins, Austin L 08 1900 (has links)
Gaius Julius Caesar remains one of the most studied characters of antiquity. His personality, political career, and military campaigns have garnered numerous scholarly treatments, as have his alleged aspirations to monarchy and divinity. However, comparatively little detailed work has been done to examine his own personal religiosity and even less attention has been paid to his religion in the context of his military conquests. I argue that Caesar has wrongly been deemed irreligious or skeptical and that his conduct while on campaign demonstrates that he was a religious man. Within the Roman system of religion, ritual participation was more important than faith or belief. Caesar pragmatically manipulated the Romans' flexible religious framework to secure military advantage almost entirely within the accepted bounds of religious conduct. If strict observance of ritual was the measure of Roman religiosity, then Caesar exceeded the religious expectations of his rank and office. The evidence reveals that he was an exemplar of Roman religio throughout both the Gallic Wars (58-51BC) and the subsequent Civil Wars (49-45BC).
20

Biodegradation of phloroglucinol and gallic acid by the soil fungus Penicillium simplicissimum /

Hameed, Nuzhat S. January 1987 (has links)
Thesis (M.Sc.) --Memorial University of Newfoundland, 1987. / Typescript. Bibliography: leaves 113-122. Also available online.

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