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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.
31

Caracter?sticas Estruturais da Mat?ria Org?nica em Organossolos H?plicos / Structural characteristics of organic matter in Histosols.

Ebeling, Adierson Gilvani 27 August 2010 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-06-27T14:38:40Z No. of bitstreams: 1 2010 - Adierson Gilvani Ebeling.pdf: 3744657 bytes, checksum: 0458139e287a489573818b522e4c02de (MD5) / Made available in DSpace on 2017-06-27T14:38:40Z (GMT). No. of bitstreams: 1 2010 - Adierson Gilvani Ebeling.pdf: 3744657 bytes, checksum: 0458139e287a489573818b522e4c02de (MD5) Previous issue date: 2010-08-27 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico, CNPq, Brasil. / The Histosols have a small geographic extension in the Brazilian territory; however, they are intensively used in family agriculture systems and have a great environmental importance. The drainage of Histosols leads to the subsidence process and other changes in the soil organic matter (SOM), with consequences in their characteristics and potential. The nature of humic substances (HSs) is determinant in the alterations of the Histosols. The characterization of the HSs allows the understanding of processes of SOM transformation in the Histosols, and their environmental impact. The objectives of this study were: to characterize Histosols from different environments and land usage intensity; and to evaluate alterations in humic fractions of SOM, by using elemental composition analyses, spectroscopic, thermal degradation, and nuclear magnetic resonance (NMR) techniques. The study was developed in eight Histosols, from the States of Rio de Janeiro, Maranh?o and Paran?, in Brazil. Their chemical properties: total organic carbon (TOC), pH, sum of bases (SB), H+, Al3+, cation exchange capacity (CEC), and V%; and physical properties: bulk density (BD), MR, MM, and OMD, were evaluated. Also, the quantitative fractionating of the HSs: fulvic acid (C-FAF), humic acid (CHAF), and humin (C-HUM), and C-FAH/C-FAF relations, C-EA/C-HUM (C-EA = C-FAF + C-FAH). The humic acids were extracted using the method of the International Humic Substances Society (IHSS), and evaluated by different techniques. The chemical attributes varied with the intensity of burning and agricultural usage. Though, in general, the Histosols presented low natural fertility, and it was related to the humic acid fraction (high ratio CFAH/ C-FAF). Amongst the SOM fractions the HUM predominated, with an average value of 59.98% of total carbon determined by the CHN; followed by the FAH. The C-FAH/C-FAF ratio diminished with the increase of agriculture usage intensity. The results of the TGI (Thermal Gravimetric Index) suggested strong resistance to thermal degradation of majority of the organic horizons. The elemental composition (%C, %H, %N, %O) of the humic acids showed large amplitude of variation between the horizons, but no pattern was observed between the Histosols. The increase of carbon content, the high values of TGI, and the reduction of oxygen content in the humic acids (HA) might explain the high thermal decomposition resistance found in the HA extracted form the Histosols. A correlation between H/C and TGI was observed, where the lower values of H/C were related to the highest resistance of the humic acids to thermal degradation. The spectroscopic and NMR techniques allowed characterizing compounds and groups of substances in the HA, showing the great potential of these tools in studies of HS from Histosols. The multivariate methods allowed a combined analysis of techniques applied in the study, showing a group of labile and recalcitrance materials in the soils. The results, in general, indicated the fragility of the Histosols areas, in terms of agricultural management and the formation environment. Their importance for the environment should be priority in comparison to agricultural usage, mainly due to their relevant part in the aquifers preservation. / Os Organossolos t?m pequena representatividade geogr?fica no Brasil, entretanto, s?o utilizados intensamente em modelos de agricultura familiar e t?m grande import?ncia ambiental. Por?m, a sua drenagem conduz ao processo de subsid?ncia e outras modifica??es na mat?ria org?nica do solo (MOS), com implica??es nas caracter?sticas dos Organossolos e em sua potencialidade. A natureza das subst?ncias h?micas (SHs) ? determinante nessas altera??es nos Organossolos. A caracteriza??o das SHs permite a compreens?o dos processos de transforma??o da MOS nos Organossolos e seu impacto no ambiente. Os objetivos deste trabalho foram: caracterizar Organossolos em v?rios ambientes e intensidade de uso agr?cola e avaliar altera??es nas fra??es humificadas da MO, atrav?s de t?cnicas de an?lise da composi??o elementar, espectrosc?picas, termodegradativas e de resson?ncia magn?tica nuclear (RMN). Foram estudados oito perfis de solos, nos Estados do Rio de Janeiro, Maranh?o e Paran?. Foram avaliadas as suas propriedades qu?micas: carbono org?nico total (COT), pH, soma de bases (SB), H+, Al3+, CTC e V%; e propriedades f?sicas: densidade do solo (Ds), RM, MM e DMO. Al?m do fracionamento quantitativo das SHs: ?cidos f?lvicos (C-FAF), ?cidos h?micos (C-FAH) e humina (C-HUM), e rela??es C-FAH/C-FAF, C-EA/CHUM (C-EA = C-FAF + C-FAH). Os ?cidos h?micos (AH) foram extra?dos pelo m?todo da Sociedade Internacional de Subst?ncias H?micas (IHSS) e avaliados por distintas t?cnicas. Os atributos qu?micos variaram com o efeito das queimadas e da intensidade de uso agr?cola; por?m, em geral, os Organossolos apresentaram baixa fertilidade natural, a qual, em geral, esteve relacionada ? fra??o ?cido h?mico (maior raz?o C-FAH/C-FAF). Dentre as fra??es da MO, a HUM predominou, com valor m?dio de 59,98% do carbono total determinado pelo CHN, seguida da FAH. A rela??o C-FAH/C-FAF diminuiu a medida que o uso agr?cola ? intensificado. Os dados do ITG (?ndice Termogravim?trico) sugeriram forte resist?ncia ? termodegrada??o para a maioria dos horizontes org?nicos. A composi??o elementar (%C, %H, %N, %O) dos ?cidos h?micos apresentou grande amplitude entre os horizontes, por?m sem padr?o diferenciado entre os Organossolos. O aumento do conte?do de carbono, os altos valores de ITG e a diminui??o do conte?do de oxig?nio nos ?cidos h?micos podem explicar a maior resist?ncia a termodecomposi??o dos AH extra?dos dos Organossolos. Foi observada correla??o entre a raz?o H/C e o ITG, onde os menores valores de H/C estiveram relacionados a maior resist?ncia dos AH ? termodegrada??o. As t?cnicas espectrosc?picas e de RMN permitiram caracterizar compostos e grupamentos nos AH, demonstrando o potencial dessas ferramentas nos estudos de SHs provenientes de Organossolos. Os m?todos de an?lise multivariada permitiram uma avalia??o conjunta das t?cnicas utilizadas, mostrando um grupo de amostras l?beis e recalcitrantes nos solos. Os resultados encontrados, em geral, indicam a fragilidade das ?reas de Organossolos, em fun??o do manejo para agricultura e do seu ambiente de forma??o. A sua import?ncia em termos ambientais deveria ser priorizada em rela??o ao uso agr?cola, principalmente pelo papel relevante na preserva??o de aqu?feros.
32

Avalia??o dos efeitos do tratamento com ?cidos graxos de cadeia curta sobre a infec??o pelo v?rus sincicial respirat?rio

Fernandes, Krist Helen Antunes 03 March 2017 (has links)
Submitted by PPG Pediatria e Sa?de da Crian?a (pediatria-pg@pucrs.br) on 2018-07-11T11:29:52Z No. of bitstreams: 1 Disserta??o Krist1107.pdf: 2340518 bytes, checksum: c4a07ad9b25622d62d44660937fb1ea0 (MD5) / Approved for entry into archive by Sheila Dias (sheila.dias@pucrs.br) on 2018-07-16T11:22:39Z (GMT) No. of bitstreams: 1 Disserta??o Krist1107.pdf: 2340518 bytes, checksum: c4a07ad9b25622d62d44660937fb1ea0 (MD5) / Made available in DSpace on 2018-07-16T11:30:20Z (GMT). No. of bitstreams: 1 Disserta??o Krist1107.pdf: 2340518 bytes, checksum: c4a07ad9b25622d62d44660937fb1ea0 (MD5) Previous issue date: 2017-03-03 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES
33

Composi??o de ?cidos graxos, teores de colesterol e ?xidos de colesterol em amostras comerciais de atuns em conservas / Fatty acid composition, cholesterol and cholesterol oxides contents in commercial samples of canned tuna

DANTAS, Natalie Marinho 04 May 2016 (has links)
CNPq / Brazil presents an important commercial fishing pole, which turns it to become relevant considering the benefits that consumption of fish plays in human nutrition. Canned fish promotes long shelf life of these food. However, foods that are rich sources of polyunsaturated fatty acids and cholesterol, such as tuna, have a great susceptibility for lipid oxidation when exposed to thermal processing. Cholesterol oxidation products (COP?s) are related to several diseases such as atherosclerosis, and can be absorbed from the diet. Thus, this study aimed to evaluate the lipid composition and COP?s production in canned tuna purchased from metropolitan area of Rio de Janeiro. Three trademarks of ?grated in brine? and ?in oil? canned tuna were evaluated. To determinate lipid oxidation, the fatty acid composition from the methyl esters of the fish and their brine were identified using gas chromatography with flame ionisation detector; cholesterol and cholesterol oxides were determined simultaneously, using high-performance liquid chromatography and confirmed by liquid chromatograph mass spectrometer (chemical ionization interface for atmospheric pressure) (APCI-MS). Tuna in ?brine? samples presented moisture contents in a range of 24.60 to 27.23g/100g; lipids contents ranging from 4.21 to 5.59g/100g; polyunsaturated fatty acids (PUFA) levels between 9.13 to 16,20g/100g, and high saturated fatty acids (SFA) contents (in a range of 54.66 to 59.85g/100g) (dry basis-DB). The nutritional quality index showed that lipid fractions presented undesirable values. These samples presented cholesterol concentration ranging from 190.95 to 399.28mg/100g, and high cholesterol oxidation products contents (between 321.42 and 414.94?g/100g- DB). Samples of ?in oil? canned tuna presented moisture and lipids contents of 31.93 to 51.33g/100g and 23.70 to 43.99g/100g, respectively; high polyunsaturated fatty acids concentration (46.06 to 49.92g/100g), especially the w6 series; and low levels of EPA and DHA amounts (in a range of 0.59 and 1.73g/100g). Cholesterol and COP?s contents varied from 135.90 to 191.92mg/100g and from 110.97 to 207.19?g/100g, respectively. Significate concentrations of cholesterol were identified in brine (18.99 to 37.10mg/100g) and ?in oil? samples (113.09 to 259.12mg/100g), and high COP?s contents were found (in a range of 230.54 and 477.12?g/100g from brine and 44.15 to 151.18?g/100g from ?in oil? samples). It was observed that there is a transference of lipids from fish to brine, as well as migration between fish lipids and vegetable oils in the ?oil? covers, changing the fatty acids profiles of both. It is considered that the production of canned fish contributes to loss of lipid quality, promotes fatty acids oxidation and induces the formation of cholesterol oxidation products. These results indicate that is necessary to conduct further studies to evaluate the occurrence of these undesirable compounds in fish products. / O Brasil possui um importante polo de pesca comercial, fato que se torna relevante considerando os benef?cios que o consumo de pescados desempenha na nutri??o humana. As conservas de peixes promovem nestes alimentos tempos de vida ?til prolongados. Entretanto, os alimentos ricos em ?cidos graxos poliinsaturados e colesterol, como os atuns, quando submetidos ao processamento t?rmico, apresentam grande potencial para a oxida??o lip?dica. Os produtos da oxida??o do colesterol (POC?s) est?o envolvidos no desenvolvimento de doen?as, como a aterosclerose, e podem ser absorvidos a partir da dieta. Desta forma, este trabalho teve como objetivos avaliar a composi??o lip?dica e a forma??o dos POC?s em conservas de atuns comercializadas na regi?o metropolitana do Rio de Janeiro. Foram avaliadas amostras de conservas ?raladas? em ?salmoura? e em ??leo? de 3 marcas comerciais. Para determina??o da oxida??o lip?dica, identificou-se a composi??o de ?cidos graxos dos atuns e respectivos l?quidos de coberturas a partir dos ?steres met?licos, atrav?s de Cromatografia Gasosa com detector de ioniza??o por chama; al?m da quantifica??o simult?nea do colesterol e dos POC?s, atrav?s de cromatografia l?quida de alta efici?ncia e confirmados por cromat?grafo l?quido com espetr?metro de massas (interface de ioniza??o qu?mica por press?o atmosf?rica) (APCI-MS). Os atuns em ?salmoura? apresentaram m?dias entre 24,60 a 27,23g/100g de umidade; entre 4,21 a 5,59g/100g de lip?deos; teores de 9,13 a 16,20g/100g de ?cidos graxos poliinsaturados (AGPI), e elevadas concentra??es de ?cidos graxos saturados (AGS) (entre 54,66 a 59,85g/100g), em base seca (BS). Foram evidenciados nos ?ndices de qualidade nutricional das fra??es lip?dicas com valores pouco desej?veis sob o ponto de vista nutricional. As concentra??es de colesterol nessas amostras variaram entre 190,95 a 399,28mg/100g, e foram identificados elevados teores de produtos de oxida??o do colesterol (entre 321,42 e 414,94?g/g/100g), em BS. As amostras de atuns em conservas contendo ??leo? apresentaram teores entre 31,93 e 51,33g/100g de umidade; entre 23,70 e 43,99g/100g de lip?deos, elevadas concentra??es de ?cidos graxos poliinsaturados (de 46,06 a 49,92g/100g), em especial os da s?rie w6 e reduzidos teores na soma de EPA e DHA (entre 0,59 e 1,73g/100g). As concentra??es de colesterol variaram entre 135,90 e 191,92mg/100g e os POC?s de 110,97 a 207,19?g/100g. Em rela??o aos l?quidos de coberturas, foram identificadas concentra??es significativas de colesterol (de 18,99 a 37,10mg/100g nas salmouras e de 113,09 a 259,12mg/100g nos ?leos, respectivamente), al?m de elevados teores de produtos de oxida??o do colesterol (entre 230,54 e 477,12?g/100g nas salmouras e entre 44,15 e 151,18?g/100g nos ?leos). Observou-se a transfer?ncia de lip?deos dos pescados para os l?quidos em ?salmoura?, al?m da migra??o de lip?deos entre os pescados e os ?leos vegetais nas conservas em ??leo?, alterando os perfis de ?cidos graxos de ambos os meios. Considera-se que a produ??o de conservas de peixes favorece a perda da sua qualidade lip?dica, promovem oxida??o de ?cidos graxos e induzem a forma??o de produtos de oxida??o do colesterol, fato que indica a necessidade da condu??o de novos estudos que avaliem a ocorr?ncia desses compostos indesej?veis oriundos da oxida??o lip?dica em produtos de pescados.
34

Estudos comparativos do ciclo de regenera??o de diferentes tipos de silicoaluminofosfatos

Chellappa, Thiago 22 March 2013 (has links)
Made available in DSpace on 2014-12-17T14:07:11Z (GMT). No. of bitstreams: 1 ThiagoC_TESE_PARCIAL.pdf: 936476 bytes, checksum: 8bf6e0f098d614d4feecc4fca3221123 (MD5) Previous issue date: 2013-03-22 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Different types of heterogeneous catalysts of the silicoaluminophosphate type, (SAPO-5, SAPO-11, SAPO-31, SAPO-34 and SAPO-41), molecular sieves with a: AFI, AEL, ATO, CHA and AFO structure, respectively, were synthesized through the hydrothermal method. Using sources such as hydrated alumina (pseudobohemita), phosphoric acid, silica gel, water, as well as, different types of organic structural templates, such as: cetyltrimethylammonium bromide (CTMABr), di-isopropylamine (DIPA), di-n- propylamine (DNPA) and tetraethylammonium hydroxide (TEOS), for the respective samples. During the preparation of the silicoaluminophosphates, the crystallization process of the samples occurred at a temperature of approximately 200 ? C, ranging through periods of 18-72 h, when it was possible to obtain pure phases for the SAPOs. The materials were furthermore washed with deionized water, dried and calcined to remove the molecules of the templates. Subsequently the samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), absorption spectroscopy in the infrared region (FT-IR), specific surface area and thermal analysis via TG/DTG. The acidic properties were determined using adsorption of n-butylamine followed by programmed termodessorption. These methods revealed that the SAPO samples showed a typically weak to moderate acidity. However, a small amount of strong acid sites was also detected. The deactivation of the catalysts was conducted by artificially coking the samples, followed by n-hexane cracking reactions in a fixed bed with a continuous flow micro-reactor coupled on line to a gas chromatograph. The main products obtained were: ethane, propane, isobutene, n-butane, n-pentane and isopentane. The Vyazovkin (model-free) kinetics method was used to determine the catalysts regeneration and removal of the coke / Diferentes tipos de catalisadores heterog?neos do tipo silicoaluminofosf?tico, (SAPO-5, SAPO-11, SAPO-31, SAPO-34 e SAPO-41), peneiras moleculares com estrutura: AFI, AEL, ATO, CHA e AFO, respectivamente, foram sintetizados pelo m?todo hidrot?rmico. Utilizando-se de fontes como ? alumina hidratada (pseudobohemita), ?cido fosf?rico, s?lica gel, ?gua e diferentes tipos de direcionadores estruturais org?nicos, tais como o: brometo de cetiltrimetilam?nio (CTMABr), di-isopropilamina (DIPA), di-n-propilamina (DNPA) e hidr?xido de tetraetilam?nio (TEOS), nas respectivas amostras. Durante a prepara??o dos silicoaluminofosfatos o processo de cristaliza??o das amostras ocorreu ? temperatura de aproximadamente 200 ?C, durante per?odos que variaram de 18-72 h, quando foi poss?vel obter as fases puras dos SAPOs. Os materiais obtidos foram lavados com ?gua deionizada, secos e calcinados para a remo??o das mol?culas dos direcionadores. Posteriormente, as amostras foram caracterizadas por difra??o de raios-X (DRX), microscopia eletr?nica de varredura (MEV), espectroscopia de absor??o na regi?o do infravermelho (FT-IR), ?rea de superf?cie espec?fica e an?lise t?rmica via TG/DTG. As propriedades ?cidas foram determinadas usando adsor??o de n-butilamina seguida de termodessor??o programada. Esses m?todos revelaram que ?s amostras dos SAPOs apresentaram uma acidez tipicamente fraca a moderada. Entretanto, uma pequena quantidade de s?tios ?cidos fortes foi tamb?m detectada. A desativa??o dos catalisadores foi conduzida pelo coqueamento artificial das amostras, seguidas das rea??es de craqueamento do n-hexano em um microrreator catal?tico de leito fixo com fluxo cont?nuo acoplado em linha com um cromat?grafo a g?s. Como principais produtos foram obtidos: etano, propano, isobutano, n-butano, n-pentano e isopentano. Para determinar a regenera??o do catalisador e a remo??o do coque foi aplicado o m?todo cin?tico Vyazovkin (Model Free Kinetics) / 2020-02-01
35

Silagens com diferentes propor??es de capim-marandu e amendoim forrageiro / Silages containing different proportions of Marandu Grass and peanut

Gomes, Fran?oise Mara 18 July 2013 (has links)
Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-01-05T11:59:39Z No. of bitstreams: 2 francoise_mara_gomes.pdf: 474916 bytes, checksum: 3c5a4eac9fcd5ab28c70fd667d29e48f (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-01-05T12:09:22Z (GMT) No. of bitstreams: 2 francoise_mara_gomes.pdf: 474916 bytes, checksum: 3c5a4eac9fcd5ab28c70fd667d29e48f (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-01-05T12:09:44Z (GMT) No. of bitstreams: 2 francoise_mara_gomes.pdf: 474916 bytes, checksum: 3c5a4eac9fcd5ab28c70fd667d29e48f (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Made available in DSpace on 2015-01-05T12:09:45Z (GMT). No. of bitstreams: 2 francoise_mara_gomes.pdf: 474916 bytes, checksum: 3c5a4eac9fcd5ab28c70fd667d29e48f (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Previous issue date: 2013 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / O estudo foi conduzido na Universidade Federal de Vi?osa, com o objetivo de avaliar as popula??es de microrganismos, as perdas de mat?ria seca, a composi??o bromatol?gica e as caracter?sticas fermentativas de silagens mistas de capim-marandu, com diferentes n?veis de amendoim forrageiro (0; 25; 50; 75 e 100%), com e sem inoculante microbiano Sil All (Alltech do Brasil). Utilizou-se o esquema fatorial 5 x 2 (cinco propor??es de amendoim forrageiro, com e sem inoculante), no delineamento inteiramente casualizado, com tr?s repeti??es. O material foi ensilado em baldes com capacidade de 20 L, providos com v?lvulas de Bunsen, e abertos 60 dias ap?s o fechamento para as avalia??es. Observou-se efeito da intera??o n?vel de amendoim forrageiro e inoculante microbiano sobre pH (P<0,05) e teores de FDNcp (P<0,01), ?cidos l?tico, propi?nico e but?rico, popula??es de fungos + leveduras (P<0,05), produ??o de gases (P<0,01), recupera??o e produ??o total de mat?ria seca. Verificou-se efeito do n?vel de amendoim forrageiro para o pH (P<0,01) e teores de MS, PB, FDA, NIDA, lignina, FDNcp, carboidratos sol?veis residuais, NH3 (P<0,05), ?cidos l?tico (P<0,01), ac?tico, propi?nico e but?rico, popula??es de bact?rias ?cido l?tico (P<0,05) e fungos + leveduras (P<0,01) e sobre a recupera??o e perdas totais de mat?ria seca. O efeito do inoculante foi observado sobre o pH (P<0,01), teores de NIDA, lignina, FDNcp, carboidratos sol?veis residuais (P<0,05), ?cidos l?tico (P<0,01) e propi?nico, e sobre recupera??o e perdas totais de mat?ria seca. Conclui-se que, a adi??o de amendoim forrageiro ao capim-marandu, no momento da ensilagem, aumenta o teor de prote?na bruta e reduz o teor de fibra, bem como proporciona perfil fermentativo adequado e boa recupera??o de mat?ria seca nas silagens. O uso do inoculante microbiano n?o apresenta benef?cios em rela??o ? composi??o bromatol?gica, mas proporciona melhor perfil fermentativo. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Zootecnia, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2013. / ABSTRACT The study was conducted at the Federal University of Vi?osa, in order to assess the populations of microorganisms, losses of dry matter, chemical composition and fermentation characteristics of silage mixed Marandu grass with different levels of peanut (0, 25 , 50, 75 and 100%), with and without inoculant Sil All (Alltech Brazil). We used a 5 x 2 factorial design (five proportions of peanut, with and without inoculation), in a completely randomized design with three replications. The material was ensiled in buckets with a capacity of 20 liters, fitted with Bunsen valves, and open 60 days after closing for evaluations. We observed a significant interaction between level of peanut and inoculation on pH (P <0.05) and levels of NDF (P <0.01), lactic acid, propionic and butyric acids, yeast fungus populations + (P <0 , 05), gas production (P <0.01), recovery and total production of dry matter. There was no effect on the level of peanut for pH (P <0.01) and DM, CP, ADF, NIDA, lignin, NDF, residual soluble carbohydrates, NH3 (P <0.05), lactic acid ( P <0.01), acetic, propionic and butyric acids, lactic acid bacteria population (P <0.05) + yeasts and fungi (P <0.01) and for total recovery and losses of dry matter. The effect of inoculum was observed on the pH (P <0.01) levels of NIDA lignin, NDF, residual soluble carbohydrates (P <0.05), lactic acid (P <0.01) and propionic, and on Total recovery and losses of dry matter. We conclude that the addition of the peanut Marandu grass at the time of ensiling increases the protein content and reduces the fiber content as well as provides adequate fermentation profile and good recovery of dry matter in the silage, regardless of the use of inoculant.
36

Formas e biodisponibilidade de f?sforo no solo em resposta ? adi??o de ?cido c?trico. / Forms and bioavailability of phosphorus in the soil in response to the addition of citric acid.

Santos, Sheila Renata January 2012 (has links)
Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-27T13:30:37Z No. of bitstreams: 5 66.pdf: 633982 bytes, checksum: fdad2ae3be9096fae7ea678fc3d85800 (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2110 bytes, checksum: b4c884761e4c6c296ab2179d378436d4 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-27T19:48:45Z (GMT) No. of bitstreams: 5 66.pdf: 633982 bytes, checksum: fdad2ae3be9096fae7ea678fc3d85800 (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2110 bytes, checksum: b4c884761e4c6c296ab2179d378436d4 (MD5) / Made available in DSpace on 2015-02-27T19:48:45Z (GMT). No. of bitstreams: 5 66.pdf: 633982 bytes, checksum: fdad2ae3be9096fae7ea678fc3d85800 (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2110 bytes, checksum: b4c884761e4c6c296ab2179d378436d4 (MD5) Previous issue date: 2012 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (Capes) / Melhorar a efici?ncia da absor??o de P no solo pelas culturas, por meio de manejos diferenciados da aduba??o fosfatada, diz respeito a um melhor aproveitamento do nutriente adicionado via fertiliza??o, que significa ganhos em produtividade. Em solos onde predominam argilas de baixa atividade e ?xidos em sua fra??o mineral, a fixa??o de P por meio dos processos de adsor??o e precipita??o torna a nutri??o fosfatada um fator limitante para produ??o da maioria das esp?cies cultiv?veis. O ?nion citrato, derivado da dissocia??o do ?cido c?trico no solo, possui elevado poder complexante de metais. Al?m disso, sua carga negativa garante afinidade com as cargas positivas dos ?xidos no solo, competindo com o fosfato pelos mesmos s?tios de liga??o. Com objetivo de verificar o potencial do ?cido c?trico em aumentar a biodisponibilidade ao milho e modificar as formas de P inorg?nico no solo, testou-se a combina??o das doses 0; 45; 90 e 180 mg dm-3 de P num Neossolo Quartzar?nico e 0; 100; 200 e 400 mg dm-3 de P num Latossolo Vermelho Amarelo, com doses equivalentes a 0; 1; 2 e 4 kg ha-1 de ?cido c?trico, em experimentos em vasos, em condi??es de casa de vegeta??o. No Neossolo Quartzar?nico, 119 mg dm-3 de P e equivalente a 0,8 kg ha-1 de ?cido c?trico proporcionaram m?ximo crescimento das plantas de milho. J? no Latossolo Vermelho Amarelo, a estimativa das doses foi de 96 mg dm-3 de P e equivalente a 2,0 kg ha-1 de ?cido c?trico. A resposta das plantas ? aplica??o do ?cido c?trico deveu-se ? solubiliza??o de formas menos l?beis aumentando as formas mais l?beis de P inorg?nico no solo. Os teores de P na planta e aqueles extra?dos por Mehlich-1e Resina de Troca Ani?nica n?o se correlacionaram quanto ? adi??o de ?cido c?trico no Latossolo Vermelho Amarelo. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Produ??o Vegetal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2012. / ABSTRACT To improve the efficiency of absorption, by crops, of P in soil, through differentiated maneuvers of phosphorus fertilization, relates to a better utilization of nutrients added through fertilization, which means productivity gains. In soils with a predominance of low activity clays and oxides in their mineral fraction, the P fixation through the processes of adsorption and precipitation makes phosphorus nutrition a limiting factor for production of most cultivable species. The anion citrate derived from citric acid dissociation of the soil has high metal complexing power. Furthermore, its negative charge ensures an affinity with the positive charges of the oxides in the soil, competing with phosphate for the same binding sites. In order to verify the potential of citric acid to increase the bioavailability for maize and to modify the forms of inorganic P in the soil, there had been tested the combination doses of 0, 45, 90 and 180 mg dm-3 of P in a Typic Quartzipsamment soil and 0; 100, 200 and 400 mg dm-3 of P in a Typic Hapludox soil, with doses of 0, 1, 2 and 4 kg ha-1 of citric acid in experiments conducted in pots under greenhouse conditions. In Typic Quartzipsamment soil, 119 mg dm-3 of P and an equivalent to 0.8 kg ha-1 of citric acid gave maximum growth of maize crops. In the Typic Hapludox soil, the estimated dose was 96 mg dm-3 of P and equivalent to 2.0 kg ha-1 of citric acid. The plant response to the application of citric acid was due to solubilization of less labile forms increasing the more labile forms of inorganic P in soil. The phosphorus content in the plant and those extracted by Mehlich-1 and Anion Exchange Resin were not correlated to the addition of citric acid in the Typic Hapludox soil.
37

Efeitos da substitui??o parcial da banha de porco por ?leo de pequi (Caryocar brasiliense) em uma dieta ocidental sobre o metabolismo, a fun??o card?aca e o estado redox celular de ratos

C?sar, Nayara Rayne 31 March 2015 (has links)
Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2016-01-04T16:31:23Z No. of bitstreams: 2 nayara_rayane_cesar.pdf: 2602002 bytes, checksum: c844463923756f76132f0190a6617bd5 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2016-01-04T16:31:46Z (GMT) No. of bitstreams: 2 nayara_rayane_cesar.pdf: 2602002 bytes, checksum: c844463923756f76132f0190a6617bd5 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-01-04T16:31:46Z (GMT). No. of bitstreams: 2 nayara_rayane_cesar.pdf: 2602002 bytes, checksum: c844463923756f76132f0190a6617bd5 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2015 / Funda??o de Amparo ? Pesquisa do estado de Minas Gerais (FAPEMIG) / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (Capes) / O padr?o diet?tico ocidental, caracterizado pelo alto consumo de gordura saturada e carboidratos refinados, favorece o ac?mulo de tecido adiposo e o surgimento de v?rias doen?as cardiometab?licas (DCM). Atualmente, tem-se considerado que n?o apenas a quantidade, mas o perfil das gorduras ingeridas pode exercer forte influ?ncia sobre o desenvolvimento dessas doen?as. Nesse contexto, v?rios estudos t?m demonstrado que o consumo de alimentos fontes de ?cidos graxos monoinsaturados (MUFA) est? associado a um menor risco para o desenvolvimento de DCM. Al?m disso, t?m sido tamb?m identificados muitos compostos bioativos presentes nos alimentos vegetais, os quais t?m sido associados a efeitos ben?ficos na redu??o do risco e, ou, no tratamento de DCM. Dentre esses compostos est?o os carotenoides, que apresentam atividade antioxidante. Nessa perspectiva, o ?leo do pequi apresenta-se como um potencial alimento funcional, dado que os MUFA representam aproximadamente 60% dos seus ?cidos graxos, e possui ainda um teor elevado de carotenoides totais. Considerando que o padr?o de consumo alimentar ocidental favorece o desenvolvimento das DCM, e que o ?leo do pequi ? um potencial alimento protetor, mas ainda n?o foi explorado nesse contexto, o objetivo deste estudo foi avaliar os efeitos da substitui??o parcial da banha de porco (rica em ?cidos graxos saturados - SFA) por ?leo de Caryocar brasiliense ? pequi (rico em MUFA e carotenoides) em uma dieta de padr?o ocidental, sobre o metabolismo, a fun??o card?aca e o estado redox celular de ratos. Ap?s uma semana de adapta??o, os animais rec?m-desmamados foram distribu?dos em tr?s grupos (n=12) e tratados durante 12 semanas. Os grupos foram identificados conforme a dieta que receberam: CTRL ? controle, dieta AIN93G; HFS ? dieta alta em gordura e sacarose; HFS-OP ? dieta alta em gordura e sacarose, com substitui??o parcial da banha de porco por ?leo de pequi (27%). O peso corporal e a ingest?o alimentar foram monitorados durante todo o per?odo experimental; a press?o arterial sist?lica (PAS) e a frequ?ncia card?aca (FC) foram aferidas na 3? e 10? semanas; as fezes das ?ltimas 72 horas foram coletadas para avalia??o das concentra??es de colesterol e triglicer?deos (TG) e, ao final do experimento, os animais foram eutanasiados por decapita??o. As cavidades abdominais e tor?cicas foram abertas para coleta de amostras: (A) cora??es: foram retirados imediatamente para avalia??o da fun??o card?aca ex vivo; posteriormente foram avaliados os n?veis de peroxida??o lip?dica e capacidade antioxidante total; (B): tecido adiposo das regi?es epididimal e retroperitoneal, que foi pesado e posteriormente utilizado para avalia??es da adiposidade e histol?gicas; (C) soro: para determina??o das concentra??es de glicose, colesterol e TG; (D) plasma: para determina??o das concentra??es de insulina, leptina e adiponectina, peroxida??o lip?dica e capacidade antioxidante total; (E) f?gados: para avalia??o das concentra??es de colesterol e TG, an?lises histopatol?gicas e peroxida??o lip?dica, capacidade antioxidante total e atividade enzim?tica (super?xido dismutase, catalase e glutationa peroxidase). Observou-se que os pesos corporais dos animais HFS-OP e HFS foram mais elevados que CTRL (p<0,05), no entanto, a deposi??o de gordura na regi?o visceral em resposta ao consumo das dietas ocidentais foi atenuada pela substitui??o da banha de porco por ?leo de pequi (p<0,05). A menor sobrecarga reduziu a deposi??o de TG no tecido hep?tico o que pode estar associado ao retardo do desenvolvimento do diabetes. De um modo geral, a fun??o card?aca foi prejudicada pelas dietas ocidentais em compara??o ao CTRL. Nas avalia??es in vivo n?o foram observados efeitos diferenciais da substitui??o parcial da banha de porco por ?leo de pequi, contudo, quando a fun??o card?aca foi avaliada ex vivo, a ingest?o do ?leo atenuou os danos ? fun??o card?aca (p<0,05), sugerindo que, ainda que modestamente, o ?leo do pequi exerceu um efeito protetor sobre as estruturas card?acas intr?nsecas. Al?m disso, foi observada uma atenua??o da peroxida??o lip?dica no tecido hep?tico para HFS-OP em rela??o ? HFS (p<0,05), sugerindo que o ?leo do pequi pode ter favorecido a incorpora??o dos MUFA e de carotenoides nas membranas dos cardiomi?citos, o que exerceu um efeito protetor. Devido ao papel prim?rio do f?gado no controle metab?lico de todo o organismo, esse efeito de prote??o contra a peroxida??o lip?dica n?o p?de ser observado nos hepat?citos. Contudo, a presen?a dos carotenoides na dieta HFS-OP fortaleceu o sistema antioxidante ex?geno, evitando que a atividade das enzimas super?xido dismutase e glutationa peroxidase fosse prejudicada em HFS-OP como observado para HFS (p<0,05). Essas adapta??es sugerem que a substitui??o parcial da banha de porco por ?leo de pequi foi capaz de atenuar alguns efeitos delet?rios da dieta ocidental sobre o metabolismo lip?dico, a fun??o card?aca e o estado redox celular de ratos. / Disserta??o (Mestrado) ? Programa Multic?ntrico de P?s-gradua??o em Ci?ncias Fisiol?gicas, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2015. / ABSTRACT The Western diet pattern, which means a high saturated fat and refined carbohydrates intake, leads to body fat accumulation and several cardiometabolic diseases (CMD). Currently, it has been considered that, not only the amount, but the fat quality, can exert a strong influence in the development of those diseases. In this context, several studies have shown that consuming foods high in monounsaturated fatty acids (MUFA) is associated with lower risk for CMD. Moreover, it has also been identified many bioactive compounds in plant foods which are associated with beneficial effects in reducing the risk, or treating DCM. Among these compounds are carotenoids, which have strong antioxidant activity. In this perspective, pequi oil is a potential functional food, since MUFA represent approximately 60% of its fatty acids content, and it is also high in several antioxidant carotenoids. So, considering that western diet pattern promotes CMD development, and pequi oil is a potential functional food, but it has not been explored in this context, the aim of this study was to evaluate the effects of a partial replacement of lard (high in SFA) by pequi oil (high in MUFA and carotenoids), into a Western diet model, on metabolism, cardiac function and cellular redox status of rats. The animals were divided into three groups (n = 12) and treated during 12 weeks: CTRL - control, AIN93G diet; HFS ? high in saturated fat and sucrose; HFS-OP - high in saturated fat and sucrose, with partial replcement of lard by pequi oil (27%). Body weight and food intake were monitored throughout the experimental period; systolic blood pressure (SBP) and heart rate (HR) were measured at the 3rd and 10th weeks; faeces from the last 72 hours were collected for evaluation of cholesterol and triglycerides (TG). At the end of the experiment, all animals were killed by decapitation, the abdominal and thoracic cavities were opened for collection of samples: (A) hearts were taken immediately to evaluate the ex vivo cardiac function; levels of lipid peroxidation and total antioxidant capacity; (B): epididymal and retroperitoneal adipose tissues were harversted, weighed and subsequently used for adiposity and histological evaluations; (C) serum: for glucose, cholesterol and TG determination; (D) plasma: for insulin, leptin and adiponectina determinations, lipid peroxidation, total antioxidant capacity; (E) livers: for cholesterol and TG levels, histopathological analyzes, lipid peroxidation, total antioxidant capacity and enzyme activities. Body weights from HFS-OP and HFS animals were equally higher than CTRL (p<0.05); however, visceral fat deposition in response to consumption of the Western diet was attenuated by replacing lard by pequi oil and it also led to less TG deposition in the liver (p<0.05). In general, cardiac function was impaired by Western diet, promoting a higher blood pressure and heart rate in vivo and a lower cardiac contractility and relaxation efficiency ex vivo (p<0,05). However, although there were no differential effects from the partial replacement of lard by pequi oil on blood pressure and heart rate in vivo, this replacement attenuated the damage to cardiac function compared to HFS (p<0.05), suggesting that, eventhough modestly, pequi oil exerted a protective effect on intrinsic cardiac structures. In addition, the partial replacement of lard by pequi oil reduced lipid peroxidation in cardiomyocytes (p<0.05) compared to HFS, which was not observed in hepatocytes. Moreover, in the hepatocytes, there were an increasing in total antioxidant capacity and catalase and glutathione peroxidase activities compared to HFS (p<0.05). These adaptations suggest that the partial replacement of lard by pequi oil mitigated some deleterious effects of the Western diet on lipid metabolism, cardiac function and cellular redox status of rats.
38

Emprego dos ?cidos graxos de cadeia curta na colite de deriva??o fecal : estudo em ratos Wistar

Oliveira, Ariano Jose Freitas de 05 September 2011 (has links)
Made available in DSpace on 2014-12-17T14:13:40Z (GMT). No. of bitstreams: 1 ArianoJFO_TESE.pdf: 4702952 bytes, checksum: 4c768ba0623fffd6e9b8beb9419b70d5 (MD5) Previous issue date: 2011-09-05 / Diversion colitis is a chronic inflammatory process affecting the dysfunctional colon, after a colostomy. It is postulated that nutritional deficiency of the colonic epithelium by the absence of short-chain fatty acids (SCFA) is one of the factors responsible for the appearance of DC and that their employment could reverse the morphological changes of the mucosa. The treatment of choice for fecal diversion colitis (DC) is the reconstruction of the intestinal tract, although they suggested therapeutic options using enemas. This study evaluates the effect of SCFA in atrophy and inflammation in excluded colonic segments before and after the installation DC. Forty Wistar rats were divided into four groups (n = 10 for each group), submitted colostomy with distal colon exclusion. Two control groups (A1 and B1) received rectally administered physiological saline, whereas two experimental groups (A2 and B2) received rectally administered short-chain fatty-acids. The A groups were prophylactically treated (5th to 40th days postoperatively), whereas the B groups were therapeutically treated (after postoperative day 40), for 07 days. Histological sections stained with HE were used for histological analysis of the thickness of the colonic mucosa excluded (t- Student p &#8804;0.05). Inflammatory reaction of the lamina propria and mucosa were measured with scores previously established (Mann Whitney p &#8804; 0.05). There was a significant thickness recovery of the colonic mucosa in group B2 animals (p = 0.0001), which also exhibited a significant reduction in the number of eosinophilic polymorphonuclear cells in the lamina propria (p = 0.0126) and in the intestinal lumen (p = 0.0256). Group A2 did not prevent the mucosal atrophy and significant increases in the numbers of lymphocytes (p=0.0006) and 50 eosinophilic polymorphonuclear cells in the lamina propria of the mucosa (p = 0.0022). Therapeutic use of short-chain fatty-acids significantly reduced eosinophilic polymorphonuclear cell numbers in the intestinal wall and in the colonic lumen; it also reversed the atrophy of the colonic mucosa. Prophylactic use did not impede the development of mucosal atrophy / Colite de deriva??o fecal (CD) ? um processo inflamat?rio cr?nico que acomete o segmento intestinal desfuncionalizado, ap?s a confec??o de colostomia. Postula-se que a defici?ncia nutricional do epit?lio col?nico pela aus?ncia de ?cidos graxos de cadeia curta (AGCC) seja um dos fatores respons?veis pelo surgimento da CD e que o emprego deles poderia reverter as altera??es morfol?gicas da mucosa. O tratamento de elei??o para a colite por deriva??o fecal (CD) ? a reconstru??o do tr?nsito intestinal, embora sejam sugeridas terap?uticas opcionais empregando enemas. O presente estudo visou estudar o efeito dos AGCC na atrofia e inflama??o de segmentos col?nicos exclu?dos, antes e depois da instala??o da CD. Quarenta ratos Wistar foram divididos em quatro grupos (n=10 para cada grupo), todos submetidos a colostomia com exclus?o do c?lon distal. Nos dois grupos controle instilou-se solu??o salina 0,9% por via retal (grupos A1 e B1) e nos dois grupos teste (grupos A2 e B2) AGCC foram instilados por via retal. O grupo A foi submetido a interven??o profil?tica, entre o 5? e o 40? dia de p?s-operat?rio (DPO), enquanto o grupo B foi submetido a interven??o terap?utica a partir o 40? DPO, durante 07 dias. Sec??es histol?gicas coradas com HE foram usadas para an?lise histol?gica da espessura da mucosa do c?lon exclu?do (t de Student com p&#8804;0,05). Rea??o inflamat?ria da l?mina pr?pria e mucosa foi quantificada com escores previamente estabelecidos (teste de Mann Whitney p&#8804;0,05). Houve significante recupera??o da espessura da mucosa col?nica dos animais do grupo B2 (p=0,0001), que, tamb?m, apresentou significativa redu??o da presen?a de xii polimorfonucleares eosin?filos (PNE) na l?mina pr?pria (p=0,0126) e na luz intestinal (p=0,0256). O Grupo A2 n?o preveniu a atrofia da mucosa e mostrou significativo aumento do n?mero de linf?citos (p = 0.0006) e da quantidade de PNE na l?mina pr?pria da mucosa (p = 0.0022). Concluiu-se que o emprego terap?utico de AGCC reduz significativamente o n?mero de polimorfonucleares eosin?filos na parede intestinal e na luz do c?lon, e tamb?m reverte a atrofia da mucosa col?nica. Entretanto, o emprego profil?tico dos AGCC n?o impede o desenvolvimento da atrofia da mucosa
39

Caracteriza??o dos marcadores qu?micos e avalia??o de atividades biol?gicas do extrato de Spondias mombin (ANACARDIACEAE)

Cabral, Barbara 11 March 2014 (has links)
Made available in DSpace on 2014-12-17T14:16:37Z (GMT). No. of bitstreams: 1 BarbaraC_DISSERT.pdf: 9281822 bytes, checksum: 18141307d7e5a4c2b984a98c9fdf7225 (MD5) Previous issue date: 2014-03-11 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Spondias mombin is a fruitful species dispersed in tropical regions of America, Africa and Asia. In Brazil, the species can be found mainly in the northern and northeastern regions. Scarce chemical and pharmacological studies have been reported for S. mombin and until this moment studies about chemical markers were not developed. In this context, the aims of this study were to characterize the chemical markers from S. mombin leaves and evaluate their anti-inflammatory, antioxidant and antiproliferative potentials. The chemical profile of the hydroethanolic extract from S. mombin leaves analyzed by HPLC-DAD, through a validated method, allowed the identification and quantification of ellagic acid and chlorogenic acid. This extract showed anti-inflammatory potential in acute peritonitis model induced by carrageenan. The hydroethanolic extract from S. mombin leaves was subjected to a liquid-liquid partition with the solvents: n-hexane, dichloromethane, ethyl acetate and n-butanol. Regarding the anti-inflammatory potential of the fractions obtained they were active; however, ethyl acetate fraction at 200 mg/kg showed highlighted results. The compounds ellagic acid and chlorogenic acid also inhibited the leukocyte migration to the site of inflammation at 2.5, 5 and 10 mg/kg. The hydroethanolic extract, fractions and the chemical markers showed significant antioxidant potential when evaluated in different assays: DPPH Free-Radical Scavenging, Superoxide Radical Scavenging, Hydroxyl Radicals Scavenging and Reducing Power. Taken together our results showed that hydroethanolic extract of S. mombin leaves has ellagic acid and chlorogenic acid as bioactive markers and it demonstrated antiinflammatory and antioxidant properties besides no cytotoxicity against 3T3 cells. It enables us to suggest S. mombin as an important species to develop herbal drugs / S. mombin ? uma esp?cie frut?fera que se encontra dispersa em regi?es tropicais da Am?rica, ?frica e ?sia. No Brasil a esp?cie pode ser encontrada em v?rios estados tendo maior preval?ncia nas regi?es norte e nordeste do pa?s. Foram descritos poucos estudos qu?micos e farmacol?gicos para a esp?cie S. mombin e at? o momento n?o foram analisados os marcadores qu?micos da esp?cie. Diante desse contexto, este trabalho buscou caracterizar os marcadores qu?micos para as folhas e frutos de S. mombin e avaliar a atividade anti-inflamat?ria, antioxidante, antiproliferativa e antimicrobiana. O extrato das folhas (EHfl) secas e dos frutos (EHfr) in natura foram preparados por macera??o em meio hidroalco?lico. Para a caracteriza??o dos compostos ativos da esp?cie S. mombin, os extratos hidroetan?licos foram submetidos ? parti??o l?quido-l?quido com solventes de polaridade crescente n- hexano (Hex), diclorometano (Dcm), acetato de etila (AcOEt) e n-butanol (ButOH). A avalia??o do perfil qu?mico das folhas por CCD e CLAE mostrou que a esp?cie ? rica em compostos fen?licos. Na an?lise por CCD foi observada a presen?a de quercetina, ?cido el?gico e canferol. A an?lise por CLAE permitiu a identifica??o e a quantifica??o de ?cido el?gico e ?cido clorog?nico no EHfl. A metodologia anal?tica foi validada segundo os par?metros estabelecidos pela RDC 899/ 2003 e pela ICH. Na an?lise qualitativa por CLAE do EHfr foram identificados o ?cido clorog?nico e a rutina. Os resultados da avalia??o da atividade antiinflamat?ria mostraram que o EHfl das folhas, nas doses de 100, 200, 300 e 500 mg/kg, apresentou efeito de inibi??o da migra??o de leuc?citos no modelo de peritonite aguda induzida por carragenina. Todas as fra??es foram ativas, no entanto, a fra??o AcOEt na dose de 200 mg/kg apresentou melhor atividade em rela??o ?s outras fra??es testadas.O EHfl e a fra??o AcOEt apresentaram importante perfil de inibi??o bacteriana no teste de difus?o em disco, principalmente frente ? bact?ria S. flexneri. O EHfl e as fra??es (Dcm, AcOEt, ButOH) das folhas assim como o EHfr apresentaram importante atividade antioxidante nos ensaios de DPPH, sequestro de radicais super?xidos, sequestro de radicais hidroxilas e poder redutor. No que se refere ? avalia??o da citotoxicidade do EHfl, das respectivas fra??es e do EHfr frente ? cultura de c?lulas de fibroblastos 3T3 n?o foi observada citotoxidade significativa. Os resultados mostraram que o EHfl possui atividade antiinflamat?ria, antioxidante e antimicrobiana. Verificou-se que o ?cido clorog?nico e o ?cido el?gico podem ser usados como marcadores biativos das folhas de S. mombin. O EHfr apresentou atividade antioxidante e foi observada a presen?a de ?cido clorog?nico e rutina. Al?m disso, n?o foi observada atividade citot?xica para o EHfr e para o EHfl
40

Estudo da oxida??o eletroqu?mica de ?cidos carbox?licos usando eletrodo de diamante dopado com boro e participa??o de esp?cies oxidantes

Queiroz, Jorge Leandro Aquino de 27 July 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-02-02T11:57:40Z No. of bitstreams: 1 JorgeLeandroAquinoDeQueiroz_DISSERT.pdf: 3260207 bytes, checksum: 6a06a1293286a9a580545ad1da83aacf (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-02-06T20:15:36Z (GMT) No. of bitstreams: 1 JorgeLeandroAquinoDeQueiroz_DISSERT.pdf: 3260207 bytes, checksum: 6a06a1293286a9a580545ad1da83aacf (MD5) / Made available in DSpace on 2017-02-06T20:15:36Z (GMT). No. of bitstreams: 1 JorgeLeandroAquinoDeQueiroz_DISSERT.pdf: 3260207 bytes, checksum: 6a06a1293286a9a580545ad1da83aacf (MD5) Previous issue date: 2016-07-27 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Neste trabalho foi estudada a oxida??o eletroqu?mica de tr?s ?cidos carbox?licos: f?rmico (FA), ac?tico (AA) e ox?lico (AO) com o ?nodo de diamante dopado com boro suportado em ni?bio. Estes ?cidos s?o comumente acumulados durante ou no final de diversos processos de oxida??o avan?ada, uma vez que s?o mais persistentes que os poluentes iniciais tratados atrav?s destes m?todos. O ?nodo de BDD ? considerado um dos melhores materiais eletrocatal?ticos para estes processos, uma vez que atua eficientemente na gera??o de esp?cies fortemente oxidantes, como os radicais hidroxila, per?xido de hidrog?nio e persulfatos. O sil?cio ? o substrato mais utilizado para deposi??o da camada de diamante, entretanto este ? um material fr?gil. Sendo assim, o ni?bio se mostra como uma alternativa promissora devido a sua estabilidade qu?mica e mec?nica. Solu??es sint?ticas contendo os tr?s ?cidos carbox?licos foram submetidas a experimentos de oxida??o an?dica tendo como par?metros investigados a densidade de corrente aplicada (30, 60, 90 e 120 mA cm-2) e a influ?ncia do eletr?lito de suporte utilizado (?cido percl?rico e sulf?rico), bem como os efeitos das diferen?as estruturais dos ?cidos. A degrada??o dos compostos org?nicos foi analisada atrav?s da demanda qu?mica de oxig?nio (COD), carbono org?nico total (TOC) e HPLC, enquanto as esp?cies oxidantes foram detectadas utilizando t?cnicas reportadas na literatura. Os par?metros de efici?ncia (TCE, MCE e consumo energ?tico) tamb?m foram obtidos. Estudos eletroanal?ticos mostraram que podem ocorrer, para estes ?cidos tanto os processos de oxida??o direta quanto indireta. A densidade de corrente se mostrou determinante na efici?ncia de remo??o, sendo obtidas as maiores remo??es de COD em maiores densidades (60,7% para o AA; 77,8% para o FA e 86,1% para o OA utilizando 120 mA cm-2). O eletr?lito de suporte tamb?m influenciou na efici?ncia de remo??o, sendo que o processo foi mais eficiente com a utiliza??o do H2SO4 devido ? participa??o dos persulfatos, o que levou a maiores remo??es de COD (34,5% pra o AA; 82,5% para o FA e 93,5% para o OA utilizando 120 mA cm-2) quando comparado com o ?cido percl?rico. Por fim, os par?metros de efici?ncia obtidos mostraram que o consumo energ?tico depende apenas da densidade de corrente aplicada, e n?o da estrutura do ?cido (maiores j implicam em maiores consumos energ?ticos); a efici?ncia total de corrente, por outro lado, sofre influ?ncia da estrutura do composto org?nico. / In this work, the electrochemical oxidation of three carboxylic acids was studied ? formic acid (FA), acetic acid (AA) and oxalic acid (OA) with niobium supported boron doped diamond anode. These acids are usually accumulated during or in the end of various advanced oxidation processes, since they are more persistent compounds than the initial pollutants. BDD anode is considered one of the best electrocatalytic materials for these processes, since that it acts efficiently on the generation of strongly oxidant species, such as hydroxil radicals, hydrogen peroxide and persulfates. Silicon is the most used substrate for the deposition of the diamond layer, but it is a fragile material. Therefore, niobium is shown as a promising alternative due to its chemical and mechanical stability. Synthetic solutions containing the three carboxylic acids were submitted to anodic oxidation experiments aiming to investigate operating parameters such as current density (30, 60, 90 e 120 mA cm-2) and supporting electrolyte (perchloric and sulfuric acids) as well as the effects of the structural differences of the acids. The degradation of the organic compounds was analyzed by means of chemical oxygen demand (COD), total organic carbon (TOC) and HPLC, while the oxidant species were detected using techniques reported on literature. Efficiency parameters (TCE, MCE and energy consumption) were also obtained. Electroanalytical studies shown that both direct and indirect oxidation processes can occur for these acids. The current density was determinant on the removal efficiency, since great COD removals were obtained on higher densities (60.7% for AA; 77.8% for FA and 86.1% for OA by applying 120 mA cm-2). The supporting electrolyte also influenced on the removal efficiency, since the process was more efficient by using H2SO4 as supporting electrolyte due to the participation of persulfates, which led to higher COD removals (34,5% for AA; 82,5% for FA and 93,5% for OA by applying 120 mA cm-2) when compared to HClO4. Finally, the efficiency parameters obtained shown that energy consumption depends only of the applied current density, and not of the acid structures (higher j implies on higher energy consumptions); the total current efficiency, on other hand, is influenced by the organic compound structure.

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