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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.
41

Organic residue analysis of Red Lustrous Wheelmade Ware vessels traded across the eastern Mediterranean during the Late Bronze Age

Steele, Valerie J. January 2008 (has links)
Red Lustrous Wheelmade Ware (RLWm ware) transport and storage vessels have been excavated from Late Bronze Age (LBA) sites across the eastern Mediterranean. These distinctive vessels were traded for the valuable commodity they contained so far unidentified. Seventy-three sherds (61 RLWm ware, 12 in local fabrics) and two visible residues were analysed for organic residues using standard lipid extraction techniques. Seven residues from a previous study were re-examined. Gas chromatography-mass spectrometry identified four materials - beeswax, bitumen, fat/oil and resin. Beeswax, found only in vessels from Hittite sites in Turkey, was probably used as a post-firing treatment. Fat/oil, present in some sherds from every site, represents the contents of the vessels and showed many of the characteristics of degraded plant oil. Two examples contained a plant sterol and three yielded ricinoleic acid, a biomarker for castor oil. Gas-chromatography compound-specific isotope ratio mass spectrometry of selected residues excluded dairy products, ruminant animal fats and fish oils as source materials for the fats/oils, while comparison with a small database of modern oils created during this study does not exclude plant oils. Selected samples analysed by high performance liquid chromatography-tandem mass spectrometry did not reveal wine residues. Data on the elemental composition of the fabric collected during another study was re-analysed and compared with data from a further published study, confirming the remarkable consistency of RLWm ware fabric. Volume calculations were also attempted to give an estimate of the capacity of the main vessel forms.
42

Síntese e desenvolvimento de métodos analíticos para o estudo de pró-fármacos dendriméricos potencialmente ativos em doenças negligenciadas / Synthesis and analytical methods development to study dendrimeric prodrugs potentially actives in neglected diseases.

Paes, Lorena Cristine 11 November 2016 (has links)
Doenças infecciosas parasitárias consideradas negligenciadas representam um grande problema de saúde pública em muitos países e regiões. Os fármacos disponíveis na terapêutica são, em geral, tóxicos e de eficácia discutível. Portanto, a descoberta e o planejamento de novos quimioterápicos são extremamente necessários. Neste contexto, os pró-fármacos dendriméricos podem ser úteis. Porém, é necessário esforço adicional para viabilizar os custos, simplificar as estratégias de síntese e investigar os comportamentos de liberação. Ademais, é importante a melhoria dos métodos analíticos, dos métodos de purificação e identificação dos produtos de síntese, para a determinação das propriedades físico-químicas e atividade biológica, visando à efetiva aplicação desta tecnologia. Face ao exposto, o objetivo deste trabalho foi estudar a identidade, pureza e liberação de dois potenciais pró-fármacos dendriméricos, baseados em 3- hidroxiflavona, planejados para serem ativos em doença de Chagas e leishmaniose. O primeiro, estruturalmente, contendo inositol como núcleo e ramos constituídos por éster da 3- hidroxiflavona com ácido málico e o segundo, estruturalmente contendo o dendrímero PAMAM-G0 (poliamidoamina de geração inicial) como transportador e ácido succínico como espaçante. Desenvolveram-se métodos adequados à determinação da 3-hidroxiflavona por HPLC-UV (Cromatografia líquida de alto desempenho, com detecção no ultravioleta) e MEKC (Cromatografia eletrocinética micelar). Comparando-se esses métodos, o método por HPLC foi mais sensível, preciso e exato na quantificação da 3-hidroflavona, enquanto o método por eletroforese capilar foi mais rápido e de menor custo. O éster da 3-hidroxiflavona com o ácido málico mostrou-se instável em soluções orgânicas, aquosas em diferentes pH e nas condições reacionais de diversas estratégias de síntese avaliadas, o que impediu a obtenção do dendrímero baseado em inositol como núcleo conforme proposto. Já o dendrímero PAMAM-G0 funcionalizado com 3-hidroxiflavona foi sintetizado, purificado e caracterizado com sucesso. Não se observou liberação da 3-hidroxiflavona a partir desse dendrímero em solução gástrica simulada (pH 1,2) e a mesma foi lenta em soluções tampão com pH entre 5,0 e 8,5, a 37,0 ºC. Ensaios de atividade biológica do PAMAM-G0-SUC-3-OH-FLAV em amastigotas de Trypanosoma cruzi, cepas Y(Curitiba) e Y(SS), comparativamente ao benznidazol e ao nifurtimox, mostraram atividade moderada e baixa seletividade. / Infectious parasitoses considered neglected diseases represent a great health problem for many countries and areas. Drugs available in the therapeutics are, generally, toxics and do not have good efficacy. So, the discovery and design of new chemotherapeutic agents are extremely needed. In this context, dendrimeric prodrugs may be useful. However, additional effort is required to make the costs accessible, to simplify the synthetic strategies and to investigate the behavior of cleavage. The improvement of analytical methods, purification methods and identification of synthetic products, in order to determine the physicochemical properties and bioactivity aiming to effectively implement this technology, is also required. Based on foregoing considerations, the objective of this work was to study the identity, purity and drug release of two potential dendrimeric prodrugs, based on 3-hydroxyflavone, designed to be active in leishmaniasis and Chagas disease. The first structurally contains myo-inositol as the core and branches consisting of esters from 3-hydroxyflavone with malic acid. The second structurally contains PAMAM-G0 dendrimer (initial generation polyamidoamine) as carrier and succinic acid as spacer. Suitable analytical methods for determining 3-hydroxyflavone by HPLC-UV (High Performance Liquid Chromatography) and MEKC (Micellar Electrokinetic Chromatography) have been developed. Comparing these methods, HPLC method showed more sensitivity, precision and accuracy in the quantification of 3-hydroxyflavone, while the capillary electrophoresis method was faster and less expensive. The ester of 3-hydroxyflavone with malic acid showed to be unstable in organic and aqueous solutions, at different pH and at reaction conditions of synthetic strategies evaluated, which prevented the obtaining of dendrimer based on mio-isositol as core. Notwithstanding, PAMAM-G0 dendrimer funcionalized with 3- hydroxyflavone was synthesized, purified and characterized successfully. There were no 3- hydroxyflavone releases from this dendrimer in simulated gastric fluid (pH 1.2) and a slow release was observed in buffer solutions with pH between 5.0 and 8.5, at 37.0 ºC. Submitted to biological assays in amastigotes of two strains of T. cruzi, Y(Curitiba) and Y(SS), compared to benznidazole e nifurtimox, PAMAM-G0-SUCC-3-OH-FLAV showed moderated activity and low selectivity index.
43

AVALIAÇÃO DA EXTRAÇÃO DE COMPOSTOS FENÓLICOS DO BAGAÇO DE MAÇÃ COM ETANOL PARA APLICAÇÃO EM SIDRA

Benvenutti, Laís 02 February 2018 (has links)
Submitted by Angela Maria de Oliveira (amolivei@uepg.br) on 2018-04-10T19:08:52Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Laís Benvenutti.pdf: 1732667 bytes, checksum: 0cbf85a73624f6269213298d5973c50f (MD5) / Made available in DSpace on 2018-04-10T19:08:52Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Laís Benvenutti.pdf: 1732667 bytes, checksum: 0cbf85a73624f6269213298d5973c50f (MD5) Previous issue date: 2018-02-02 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A maçã apresenta alta concentração de compostos fenólicos, distribuídos em diferentes classes as quais apresentam capacidade antioxidante. Além disso, conferem efeito positivo na formação do sabor, cor e aroma em bebidas derivadas da fruta. No entanto, durante o processamento, parte da composição fenólica fica retida no bagaço, principal subproduto da agroindústria da maçã. Desta forma, este trabalho teve como objetivo a otimização da extração de compostos fenólicos presentes no bagaço da maçã utilizando solvente de grau alimentício, visando sua aplicação em sidras a fim de melhorar as características tecnológicas, nutricionais e sensoriais do produto final. Nos ensaios de extração foram avaliados os efeitos da concentração de solvente (etanol), temperatura e razão sólido/líquido sobre o rendimento e atividade antioxidante dos extratos, utilizando o método de superfície de resposta (MSR). Além disso, foi estudada a cinética da extração, bem como a estabilidade do extrato. A análise de regressão linear múltipla acoplada ao MSR sugeriu que a extração seja efetuada utilizando etanol 60%, a 50 °C, na razão sólido/líquido de 1:20 (m/v). Por meio de um modelo cinético de primeira ordem foram avaliados os efeitos do tempo e da temperatura sobre a concentração de equilíbrio da extração, a qual foi atingida aproximadamente aos 50 minutos, independente da temperatura, com teores de 1852,77; 1728,35 e 1265,29 mg CAT/kg para as temperaturas de 50, 35 e 20 °C, respectivamente. A partir desses resultados, a energia de ativação necessária para que ocorra a transferência do soluto foi 9,01 kJ/mol. Em geral, os flavonoides apresentaram boa estabilidade durante período de 90 dias, sendo sugerido armazenamento ou aplicação sob temperatura de 10 °C em pH de aproximadamente 3,5. O extrato obtido nas melhores condições foi adicionado ao mosto antes do inóculo de levedura e a fermentação foi monitorada por meio do estudo cinético. Os mostos e pontos da fermentação (1, 4, 7, 11 e 15 dias) foram avaliados quanto aos fenóis individuais, açúcares e etanol em cromatografia líquida de alta eficiência (CLAE). Além disso, foi avaliada a composição fenólica total, flavonoides totais, flavanóis, flavonóis e atividade antioxidante, bem como, o teor de acidez total titulável, pH e cor. Os produtos finais foram analisados sensorialmente quanto à intensidade de cor, acidez, adstringência e amargor por meio de uma escala estruturada, e quanto à qualidade do odor em escala hedônica de aceitação. A adição do extrato aumentou cerca 40% a concentração de flavonoides totais, apresentando glicosídeos de quercetina, compostos presentes apenas no epicarpo da maçã, os quais foram um dos compostos relacionados com o aumento da atividade antioxidante na sidra com adição de extrato. A adição do extrato também resultou em maior intensidade de cor e percepção do amargor e adstringência. Apesar das alterações na composição fenólica, a adição do extrato não prejudicou a qualidade do odor do produto final. Portanto, o extrato fenólico obtido com etanol em condições otimizadas foi capaz de reincorporar parte dos compostos bioativos retidos no bagaço, aumentando a capacidade antioxidante e alterando características sensoriais responsáveis pela aceitabilidade da bebida. / Apple has high amounts of phenolic compounds, distributed in different classes which show antioxidant capacity. In addition, the phenolic compounds contribute to flavor, color and aroma in apple beverages. However, most of the phenolic compounds, especially the flavonoids, are retained in the apple pomace, during processing. In this way, this work aimed to optimize the flavonoids extraction from apple pomace using food grade solvent, and to apply the extracts in ciders in order to improve the technological, nutritional and sensorial characteristics of the final product. In the extraction experiments, the effects of solvent concentration (ethanol), temperature and solid/liquid ratio on process yield and antioxidant activity of the extracts were evaluated using response surface methodology (RSM). In addition, the extraction kinetics as well as the stability of the extract were studied. The multiple linear regression analysis coupled to RSM suggested that the extraction be performed using ethanol 60% at 50 °C and with solute-solvent ratio of 1:20 (w/v). The effects of time and temperature on the equilibrium concentration of the extraction were evaluated, which was reached at approximately 50 minutes with contents of 1852.77; 1728.35 and 1265.29 mg CAT/kg for the temperatures of 50, 35 and 20 ° C, respectively. The activation energy required for solute transfer to occur was determined, 9.01 kJ mol-1. In general, the flavonoids showed good stability during the period of 90 days, being suggested its storage or application under a temperature of 10 °C and pH about 3.5. The extract obtained under the best conditions was added to the must prior to addition of the yeast inoculum and the fermentation was monitored by kinetic study. The musts and ciders (1, 4, 7, 11 and 15 days) were evaluated as to the individual phenols and sugar and ethanol contents were quantified in high performance liquid chromatography (HPLC). In addition, the total phenolic composition, total flavonoids, flavanols, flavonols and antioxidant activity, as well as total titratable acidity, pH and color were evaluated. The final products were sensorially analyzed for color intensity, acidity, astringency and bitterness by means of a structured scale. The odor quality was evaluated in a hedonic scale of acceptance. The addition of the extract increased about 40% in the total flavonoid content. Quercetin glycosides, compounds present only in the apple epicarp, were found, being one of the compounds associated for the increase in antioxidant activity. The cider with the extract addition showed higher intensity of color and perception of the bitterness and astringency. Despite the changes in phenolic composition, the addition of the extract did not affect the odor quality of the final product. Therefore, the phenolic extract obtained with ethanol under optimized conditions was able to reincorporate bioactive compounds retained in the pomace, increasing the antioxidant capacity and changing sensorial characteristics responsible for the acceptability of the beverage.
44

Development and Validation of HPLC Methods for Analytical and Preparative Purposes

Lindholm, Johan January 2004 (has links)
<p>This thesis concerns the development and validation of high performance liquid chromatography (HPLC) methods aimed for two industrially important areas: (i) analysis of biotechnological synthesis and (ii) determination of adsorption isotherm parameters. There is today a lack of detailed recommendations for analytical procedures in the field of biotechnological production of drugs. Therefore, guidelines were given for analytical development and validation in this field; the production of 9α-hydroxyprogesterone was used as model. In addition, a rapid method using HPLC coupled with diode-array-detection (DAD) and mass spectrometry (MS), was developed for the preliminary identification and quantification of the product. In addition, requirements and recommendations were developed for the selection of the internal standard and for its inclusion in the process liquid. By using this approach the precision and accuracy of the quantitative method were considerably improved. </p><p>Preparative chromatography is a powerful separation method for the purification of pure compounds from more or less complex sample mixtures. One such mixture can be the process liquid from a fermentation, another example can be a racemic mixture of compounds whose enantiomeric constituents must be isolated. Computer-assisted modeling can be used to optimize preparative chromatography. However, competitive adsorption isotherm parameters are required as input data for the computer simulations. In this thesis, a new injection technique, based on a firm theoretical basis, was developed for the peak perturbation (PP) method allowing the determination of binary competitive adsorption isotherm parameters from a broad concentration range. With the new method the determination of adsorption isotherm parameters from a quaternary mixture could be done for the first time. The profiles simulated with these parameters showed excellent agreement with the corresponding experimental profiles, validating the accuracy of the adsorption isotherm parameters derived by the new method.</p>
45

Development and Validation of HPLC Methods for Analytical and Preparative Purposes

Lindholm, Johan January 2004 (has links)
This thesis concerns the development and validation of high performance liquid chromatography (HPLC) methods aimed for two industrially important areas: (i) analysis of biotechnological synthesis and (ii) determination of adsorption isotherm parameters. There is today a lack of detailed recommendations for analytical procedures in the field of biotechnological production of drugs. Therefore, guidelines were given for analytical development and validation in this field; the production of 9α-hydroxyprogesterone was used as model. In addition, a rapid method using HPLC coupled with diode-array-detection (DAD) and mass spectrometry (MS), was developed for the preliminary identification and quantification of the product. In addition, requirements and recommendations were developed for the selection of the internal standard and for its inclusion in the process liquid. By using this approach the precision and accuracy of the quantitative method were considerably improved. Preparative chromatography is a powerful separation method for the purification of pure compounds from more or less complex sample mixtures. One such mixture can be the process liquid from a fermentation, another example can be a racemic mixture of compounds whose enantiomeric constituents must be isolated. Computer-assisted modeling can be used to optimize preparative chromatography. However, competitive adsorption isotherm parameters are required as input data for the computer simulations. In this thesis, a new injection technique, based on a firm theoretical basis, was developed for the peak perturbation (PP) method allowing the determination of binary competitive adsorption isotherm parameters from a broad concentration range. With the new method the determination of adsorption isotherm parameters from a quaternary mixture could be done for the first time. The profiles simulated with these parameters showed excellent agreement with the corresponding experimental profiles, validating the accuracy of the adsorption isotherm parameters derived by the new method.
46

Dynamics of astaxanthin, tocopherol (Vitamin E) and thiamine (Vitamin B1) in the Baltic Sea ecosystem : Bottom-up effects in an aquatic food web

Häubner, Norbert January 2010 (has links)
The thesis combines laboratory experiments and field expeditions to study production, transfer and consumption of non-enzymatic antioxidants and thiamine in an aquatic food web. In particular, I (1) documented spatial and seasonal variation of tocopherols and carotenoids in the Baltic Sea pelagic food web, and (2) examined the effects of abiotic and biotic factors on tocopherol, carotenoid and thiamine concentrations in phytoplankton, zooplankton and fish. Moderate differences in temperature and salinity affected α-tocopherol, β-carotene and thiamine production in microalgae. Furthermore, the results suggest that acute stress favors the expression of non-enzymatic antioxidants rather than enzymatic antioxidants. Because production of α-tocopherol, β-carotene and thiamine differ markedly between microalgae, the availability of non-enzymatic antioxidants and thiamine is likely to be highly variable in the Baltic Sea and is difficult to predict. The transfer of non-enzymatic antioxidants from phytoplankton to zooplankton was biomass dependent. The field expeditions revealed that phytoplankton biomass was negatively associated with α-tocopherol concentration in mesozooplankton. Thus, increased eutrophication of the Baltic Sea followed by an increase in phytoplankton biomass could decrease the transfer of essential biochemicals to higher levels in the pelagic food web. This could lead to deficiency syndromes, of the kind already observed in the Baltic Sea. Astaxanthin is synthesized from precursors provided by the phytoplankton community. Thus biomass dependent transfer of astaxanthin precursors from phytoplankton to zooplankton could be responsible for astaxanthin deficiency in zooplanktivorous herring. Astaxanthin in herring consists mostly of all-Z-isomers, which are characterized by low bioavailability. Therefore, astaxanthin deficiency in salmon could be explained by the low concentration of this substance and its isomeric composition in herring.
47

Développement d'une technique optique ayant pour but l'analyse de procédés en ligne de comprimés pharmaceutiques

Cournoyer, Antoine January 2008 (has links)
Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal
48

Compostos carbonílicos no ar em ambientes de trabalho de carvoarias na Bahia

Carvalho, Albertinho Barreto de 16 September 2016 (has links)
Submitted by Ana Hilda Fonseca (anahilda@ufba.br) on 2016-09-16T13:51:29Z No. of bitstreams: 1 Tese Albertinho.pdf: 2368551 bytes, checksum: 417090fff955b8696ce1e600d35af5e0 (MD5) / Approved for entry into archive by Vanessa Reis (vanessa.jamile@ufba.br) on 2016-09-16T14:11:51Z (GMT) No. of bitstreams: 1 Tese Albertinho.pdf: 2368551 bytes, checksum: 417090fff955b8696ce1e600d35af5e0 (MD5) / Made available in DSpace on 2016-09-16T14:11:51Z (GMT). No. of bitstreams: 1 Tese Albertinho.pdf: 2368551 bytes, checksum: 417090fff955b8696ce1e600d35af5e0 (MD5) / CNPq, à CAPES e à FINE / Este trabalho foi realizado com os seguintes objetivos: apresentar uma metodologia analítica aplicável à determinação de compostos carbonílicos (CC) em fase vapor, em amostras estacionárias e pessoais coletadas em ambientes de trabalho de carvoarias; determinar o perfil dos CC presentes no ar inalado pelos trabalhadores e; quantificar os CC no ar, na fase vapor, em locais de trabalho e na zona respiratória de trabalhadores carvoeiros. Os trabalhos de campo foram realizados em quatro carvoarias que produziam o carvão a partir da queima de pinho e de eucalipto, todas localizadas a cerca de 150 km, a nordeste de Salvador. Cartuchos Sep-Pak® C18 impregnados com solução ácida a 0,2% de 2,4 dinitrofenilhidrazina coletaram eficientemente os CC atmosféricos, em vazões em torno de 0,1 L/min e quando a duração da coleta foi de, no máximo, 240 minutos, para as amostras pessoais e 120 minutos, para as estacionárias. Foram desenvolvidos dois protocolos analíticos (Método “1” e Método “2”), ambos por cromatografia líquida de alta eficiência utilizando bomba com gradiente de eluição de solventes e sistema de detecção por UV/Visível (365 nm), para a separação e quantificação das 2,4-dinitrofenilhidrazonas de vários CC. O Método “1” permitiu separar e quantificar, em menos de 16 minutos, acetaldeído, acroleína, benzaldeído, ciclohexanona, ciclopentanona, 2- etil hexanal, formaldeído, furfural, hexanal, 2-hexenal, octanal, 2-pentenal, propanal, e propanona, com destaque para a separação dos pares acroleína-furfural e propanona-propanal. Além disso, permitiu estimar a soma das concentrações dos isômeros C4, butanal-isobutanal- butanona. O Método “2” permitiu separar e quantificar, em menos de 30 minutos, 13 dos 17 CC citados para o Método “1”. Por este método foi possível separar a butanona da mistura de butanal e isobutanal. O mesmo não ocorreu com a acroleína e o furfural, que co-eluíram. Os limites de detecção e de quantificação para o formaldeído, o acetaldeído e a propanona foram bastante afetados pelos níveis desses compostos encontrados nos brancos de amostra. Acetaldeído, formaldeído, furfural, isômeros C4 e propanona foram os CC confirmados em todas as amostras coletadas, nas quatro carvoarias. Vários outros CC desconhecidos foram detectados nas amostras. Ciclopentanona, 2-pentenal e CC acima de C8 não foram detectados nas amostras pelos dois métodos cromatográficos. Em amostras válidas foram determinadas concentrações de formaldeído entre 15,0 e 139,1 µg m-3, de acetaldeído entre 37,9 e 164,8 µg m-3, de propanona entre 9,6 e 483,0 µg m-3, de furfural entre 38,9 e 113,7 µg m-3 e de isômeros C4 (butanal+isobutanal+butanona) entre 9,8 e 132,4 µg m-3, em amostras pessoais. Em amostras estacionárias, as faixas de concentrações desses mesmos compostos foram respectivamente, 20,4 a 160,2 µg m-3, 118,6 a 283,6 µg m-3, 327,5 a 643,6 µg m-3, 69,9 a 162,9 µg m-3 e 100,0 a 176,1 µg m-3. Os resultados indicam que os trabalhadores das carvoarias se expõem a concentrações de formaldeído, acetaldeído e furfural acima dos limites estabelecidos por alguns organismos internacionais, como o National Institute for Occupational Safety and Health - NIOSH e o Health Based Exposure Levels Committee - HBELC, ambos dos Estados Unidos. Estes são os primeiros resultados de concentrações de CC no ar obtidos em ambientes de trabalho e na zona respiratória de trabalhadores de carvoarias, que se tem conhecimento até o momento. / The goals of the present work were to present an analytical methodology applicable to the determination of carbonyl compounds (CC) in vapor phase, in area and personal samples collected in charcoal company workplaces; to determine the CC profile in air inhaled by charcoal workers; and to quantify the CC in vapor phase in air of workplaces and breathing zone of workers in charcoal companies. The measurements were obtained in air samples collected in four companies located about 150 km north of Salvador, Bahia, Brazil, which burn eucalyptus and pinus to produce charcoal. The results showed that CC were efficiently collected on Sep-Pak® C18 cartridges coated with 0.2% acidic solution of 2,4- dinitrophenylhydrazine when the sampling flow rates were around 100 mL/min and the sampling time was 240 minutes for the personal samples and 120 minutes for area samples. Two chromatographic methods (Method 1 and Method 2) for separation and quantification of several 2,4-dinitrophenylhydrazones (2,4-DNPHO) were developed using a high performance liquid chromatography system with a gradient pump for the solvent elution and a UV detector (365 nm). Method 1 was able to separate and quantify, in less than 16 minutes, the 2,4- DNPHO of acetaldehyde, acrolein, benzaldehyde, cyclohexanone, cyclopentanone, 2-ethyl hexanal, formaldehyde, furfural, hexanal, 2-hexenal, octanal, 2-pentenal, propanal, and propanone, and estimated the sum of C4 isomers, butanal-isobutanal-butanone. This method separated well acrolein from furfural and propanal from propanone hydrazones. Method “2” allowed separation and quantification, in less than 30 minutes, of 13 of the 17 CC listed for Method 1. This method separated butanone from other components of the C4 mixture and enables the separation of acrolein from furfural. In both methods, the detection and the quantification limits of acetaldehyde, formaldehyde, and propanone were affected by the amount of these compounds found in the blank samples. Acetaldehyde, formaldehyde, furfural, C4 isomers, and propanone were the CC confirmed in all samples collected in all charcoal companies. Several unknown CC were also found. Cyclopentanone, 2-pentenal, and carbonyl compounds with more than 8 carbon atoms were not detected in any of the samples by these methods. Concentrations of formaldehyde, acetaldehyde, propanone, furfural, and C4 isomers (butanal+isobutanal+butanone) found in personal samples ranged between 15.0 and 139.1 µg m-3, 37.9 and 164.8 µg m-3, 9.6 and 483.0 µg m-3, 38.9 and 113.7 µg m-3, and 9.8 and 132.4 µg m-3, respectively. In area samples, the concentrations of the same CC were between 20.4 and 160.2 µg m-3, 118.6 and 283.6 µg m-3, 327.5 and 643.6 µg m-3, 69.9 and 162.9 µg m-3, and 100.0 and 176.1 µg m-3. These results indicated that charcoal workers were exposed to formaldehyde, acetaldehyde, and furfural concentrations that exceed the limit values suggested by the National Institute for Occupational Safety and Health - NIOSH and the Health Based Exposure Levels Committee - HBELC. These were the first results of CC concentrations in workplace air and in breathing zone of charcoal workers reported in the scientific literature up to this mome
49

Biodisponibilidade e tolerabilidade do diclofenaco de sódio via tópica ou oral em pôneis sadios / Bioavailability and tolerability of topic and oral diclofenac sodium in healthy ponies

Azevedo, Marcos da Silva 24 February 2011 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / Studies on the topical use of diclofenac in horses deal mostly with pharmacokinetics and the clinical effect of the medication, few studies addressed its tolerability or its oral use. The aim of this study was to obtain data related to pharmacokinetics and distribution of diclofenac sodium in synovial fluid after oral or topical administration in healthy ponies as well as to evaluate the tolerability of oral and topical diclofenac sodium administered on a frequency similar to a treatment period. Healthy ponies were divided into three groups and treated with topical (group I, n = 6) or oral (group II, n = 6) diclofenac at a dose of 2.5 mg kg-1 and oral phenylbutazone (group III, n = 3) at a dose of 2.2 mg kg-1. To evaluate the bioavailability blood samples were collected at different times, from 30 minutes to 144 hours and synovial fluid samples 6, 12 and 24 hours, after starting treatment. Blood samples collected 24 hours before and until 144 hours after starting treatment were used for CBC, WBC, biochemical and coagulation profiles. A significant difference was found between group I and group II on prothrombin time, activated partial thromboplastin time, fibrinogen, hematocrit, hemoglobin, erythrocytes, total leukocytes, neutrophils, band cells, lymphocytes, eosinophils, and alkaline phosphatase. Similar results were found between group II and group III, however, the activated partial thromboplastin time did not differ. Even though the plasma concentration of diclofenac sodium was higher in group II than in group I, the synovial concentration tended to be higher in group I. The diclofenac bioavailability and tolerability data obtained in ponies showed that the topic administration delivered therapeutic concentrations of diclofenac and proved to be safer, as the oral administration resulted in blood changes. / Os estudos sobre a utilização tópica do diclofenaco conduzidos na espécie equina abordam em sua maioria a farmacocinética e o efeito clínico desta medicação. A tolerabilidade frente ao diclofenaco e a utilização deste medicamento por via oral têm sido pouco estudadas. Nossos objetivos foram obter dados relacionados à farmacocinética sanguínea e distribuição do diclofenaco de sódio no líquido sinovial, após a administração oral e tópica em pôneis sadios, bem como avaliar a tolerabilidade do diclofenaco de sódio administrado por via oral e tópica, usando uma frequência de administração semelhante a um período de tratamento. Pôneis clinicamente sadios foram divididos em três grupos e tratados com diclofenaco por via tópica (grupo I, n=6) e oral (grupo II, n=6), na dose de 2,5 mg kg-1 e fenilbutazona oral (grupo III, n=3) na dose de 2,2 mg kg-1. Para avaliar a biodisponibilidade foram coletadas amostras de sangue em diferentes momentos, desde 30 minutos até 144 horas após início do tratamento e amostras de líquido sinovial as 6, 12 e 24 horas, após o início do tratamento. Amostras de sangue foram coletadas a cada 24 horas até 144 horas após início do tratamento para hemograma, leucograma, bioquímico e coagulograma. Diferenças significativas foram encontradas entre o grupo I e o grupo II em determinados tempos no tempo de protrombina, tempo de tromboplastina parcial ativado, fibrinogênio, hematócrito, hemoglobina, hemácias, leucócitos totais, segmentados, bastonetes, linfócitos, eosinófilos e fosfatase alcalina. Resultados semelhantes foram observados entre o grupo II e o grupo III, no entanto o tempo de tromboplastina parcial ativado não apresentou diferença. Embora a concentração plasmática do diclofenaco de sódio no grupo II tenha sido mais elevada que no grupo I, a concentração sinovial foi maior no grupo I. Os dados obtidos sobre a biodisponibilidade e tolerabilidade do diclofenaco em pôneis mostram que a aplicação tópica é superior à oral por resultar em concentrações sinoviais mais elevadas do fármaco, além de ser mais segura, pois não alterou significativamente os parâmetros avaliados.
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AvaliaÃÃo das potencialidades biotecnolÃgicas da semente de goiaba (Psidium guajava L.) / Evaluation of biotechnological potential of the guava seed (Psidium guajava L.)

Ana Maria Athayde UchÃa Thomaz 20 May 2014 (has links)
CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior / FundaÃÃo de Amparo a Pesquisa do Estado do Piauà / Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / VÃrios estudos tÃm associado efeitos benÃficos à saÃde, ao consumo regular de frutos, vegetais, grÃos e à presenÃa de substÃncias antioxidantes nesses alimentos, assim, o presente trabalho objetivou avaliar as potencialidades biotecnolÃgicas da semente de goiaba (Psidium guajava L.), em pà atravÃs de tÃcnicas instrumentais cientificamente reconhecidas. Foram analisadas sementes de goiaba vermelha em pÃ, da variedade Paluma cedidas por uma indÃstria produtora de polpa congelada de frutos. Foram elaborados produtos de panificaÃÃo com substituiÃÃo de 5 e 10% da farinha de trigo pela semente de goiaba em pÃ, e avaliada a aceitabilidade e a intenÃÃo de compra. Foram realisadas anÃlise de composiÃÃo nutricional, compostos bioativos, qualidade microbiolÃgica e perfil de Ãcido graxo da semente de goiaba em pÃ. Extratos acetÃnico, etanÃlico e metanÃlico foram utilizados para quantificar os teores de fenÃlicos totais, flavanÃides totais, taninos totais, determinar a atividade antioxidante por diferentes mÃtodos in vitro (DPPH, sistema &#946;- caroteno/Ãcido linoleico e Rancimat) e avaliar a toxicidade frente à Artemia salina sp. Identificou-se e a quantificou-se por cromatografia lÃquida de alta eficiÃncia (CLAE) os compostos fenÃlicos no extrato acetato de etila. Os resultados permitiram comprovar que a substituiÃÃo de 5% e 10% de farinha de trigo na massa do bolo doce e na pizza sabor portuguesa apresentaram melhor aceitabilidade e intenÃÃo de compra, comparado ao produto sem substituiÃÃo. A composiÃÃo quÃmica e nutricional da semente de goiaba em pà exibiu quantidades variÃveis de macro e micronutrientes, com alta concentraÃÃo de fibra dietÃtica (63,94 g/100g), proteÃna (11,19 g/100g), ferro (13,8 mg/100g), zinco (3,31 mg/100g) e reduzido teor calÃrico (182 kcal/100g). Apresentou quantidades significativas de compostos bioativos como Ãcido ascÃrbico (87,44 mg/100g), carotenoides totais (1,25 mg/100 g), licopeno (182  0.09 Âg/100g) e fibra dietÃtica insolÃvel (63,55 g/100g). O perfil lipÃdico mostrou uma predominÃncia de Ãcido graxo insaturado (87,06%), especialmente Ãcido linolÃico (w6) e Ãcido olÃico (w9). NÃo apresentou contaminaÃÃo microbiana e nem toxicidade frente a Artemia salina sp. O extrato acetÃnico apresentou maior concentraÃÃo de compostos fenÃlicos, flavonÃides e taninos totais 49,70Â0,48 mgEAG/g; 1,529Â0,04 mgEQ/g; 41,159Â2,64 mgEAT/g, respectivamente. O extrato acetÃnico tambÃm obteve o maior poder antioxidante, no ensaio de DPPH, IC50 de 4,33Â0,08 Âg/mL. No sistema de autooxidaÃÃo do &#946;-caroteno/Ãc. linolÃico, o extrato etanÃlico (IC50 0,193Â0,07Âg/mL) apresentou atividade antioxidante estatisticamente semelhante ao BHT. Quanto ao ensaio de Rancimat, os extratos etanÃlico (6,41Â0,07 h) e acetÃnico (6,35Â0,00 h), conseguiram preservar a estabilidade oxidativa do Ãleo de soja por um perÃodo de tempo maior e estatisticamente nÃo diferiu do Ãleo de soja adicionado de BHT (6,44Â0,01 h). Dos compostos fenÃlicos identificados o resveratrol e a cumarina foram os que apresentaram maior concentraÃÃo, 39,0Â0,02 e 48,79Â0,02 mg/100g, respectivamente. Assim, conclui-se que a semente de goiaba em pà podem ser consideradas uma fonte barata e rica em compostos antioxidantes. Sua utilizaÃÃo seria uma alternativa viÃvel para evitar o desperdÃcio e contribuir para minimizar o impacto ambiental, alÃm da possibilidade de serem incorporados nas indÃstrias de alimentos, farmacÃuticas e nutracÃuticas / Several studies have associated beneficial effects on health to the regular consumption of fruits, vegetables, grains due to the presence of antioxidants in these foods, and so the present study aimed to evaluate the potential of biotech guava seed (Psidium guajava L.), and the main metabolites responsible for its antioxidant activity. Powder from red guava seeds was analyzed, made from the Paluma variety donated by an industry producing frozen fruit pulp. Bakery products were prepared with the substitution of 5 and 10% of wheat flour by guava seed powder, and the acceptability and purchase intent were measured. Analyses of nutritional composition, bioactive compounds, microbiological quality and profile fatty acid of the guava seed powder were carried out. Acetonic, ethanol and methanol extracts were used to quantify the levels of total phenolics, total flavonoids, tannins, to determine the antioxidant activity in different in vitro methods (DPPH, &#946;-carotene / linoleic acid system and Rancimat) and to evaluate the toxicity from Artemia salina sp. The phenolic compounds in ethyl acetate extract were identified and quantified by high performance liquid chromatography (HPLC). The results showed that replacing 5% and 10% of wheat flour in sweet cake and Portuguese flavor pizza dough showed better acceptability and purchase intention, compared to the product without replacements. The chemical and nutritional composition of guava seed powder exhibited varying amounts of macro and micronutrients, with a high concentration of dietary fiber (63.94 g/100 g), protein (11.19 g/100 g), iron (13.8 mg / 100 g), zinc (3.31 mg/100 g) and reduced calorie (182 kcal/100g). Significant amounts of bioactive compounds such as ascorbic acid (87.44 mg/100g), total carotenoids (1.25 mg/100 g), lycopene (182  0.09 &#956;g/100g) and insoluble dietary fiber (63.55 g/100 g) were also found. The lipid profile showed a predominance of unsaturated fatty acid (87.06%), especially linoleic acid (w6) and oleic acid (w9). a microbialogic test showed negative contamination, and no toxicity was found using Artemia salina sp. The acetonic extract showed the highest concentration of phenolic compounds, flavonoids and tannins 49.70  0.48 mgEAG / g; 1.529  0.04 mgEQ / g; 41.159  2.64 mgEAT / g, respectively. The acetonic extract also showed the highest antioxidant powder, in the DPPH assay, IC50 of 4.33  0.08 mg / mL. In the autoxidation of &#946;-caroteno/ linoleic acid system, the ethanol extract (IC50 0.193  0.07 mg / mL) showed antioxidant activity statistically similar to BHT. The Rancimat test, the ethanolic extracts (6.41  0.07 hr) and acetone (6.35  0.00 hr) were able to preserve the oxidative stability of soybean oil for a longer period of time and did not statistically differ from soybean oil added BHT (6.44  0.01 hr). Of the phenolic compounds identified, resveratrol and coumarin presented the highest concentrations, 39.0  0.02 and 48.79  0.02 mg/100g, respectively. Thus, it can be concluded that guava seed powder can be considered an abundant source of antioxidants. Its use would be a feasible alternative to avoid waste and contribute to minimizing the environmental impact, in addition to its incorporation in the food, pharmaceutical and nutraceutical industries.

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