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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.
1

Morfologia, anatomia e sistematica do genero Ouratea Aublet (Ochnaceae) : levantamento preliminar das caracteristicas de importancia taxonomica e avaliação das classificações vigentes

Yamamoto, Kikyo, 1954- 07 August 1989 (has links)
Orientador: Graziela Maciel Barroso / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-07-19T01:53:30Z (GMT). No. of bitstreams: 1 Yamamoto_Kikyo_M.pdf: 12344445 bytes, checksum: 1dec03cf69ca5057774750488394255d (MD5) Previous issue date: 1989 / Resumo: O genero, Duratea Aublet (Ochnaceae-Ochnoideae) é classificado, segundo os ultimos estudos taxonomicos, na subtribo Duratinae, e considerando restrito à região neotropical (Duratea s.s.). A última revisão taxonômica geral data de 1876. Como subsidio para uma futura revisão do gênero, fez-se um levantamento geral do valor diagnóstico dos caracteres morfológicos e uma avaliação dos dados anatômicos utilizados por P. van Tieghem na descrição de taxons criados a partir do genero Duratea s.l., entre os anos de 1902 a 1903¿Observação: O resumo, na íntegra poderá ser visualizado no texto completo da tese digital / Abstract: The genus Duratea Aublet (Ochnaceae-Ochnoideae), is classifyed, in the last taxonomic studies, in the subtribe Duratinae of the tribe Ochneae, and is considered restrict to the neotropical region (Duratea s.s.). The last revision of this genus was presented in 1876. In order to help a future taxonomic revision, it is presented here a general analysis of the taxonomic value of morphological characters, as well as of the anatomical characters applied by P. van Tieghem in the descriptions of taxa separated by this author from Duratea s.l. between 1902 and 1903...Note: The complete abstract is available with the full electronic digital thesis or dissertations / Mestrado / Biologia Vegetal / Mestre em Ciências Biológicas
2

Desenvolvimento de formulação cosmética contendo carreadores lipídicos nanoestruturados à base de manteiga de Ourateasp. : uma estratégia nanotecnológica para o aumento da hidratação cutânea

Galvão, Juliana Gouveia 20 February 2015 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Nanostructured lipid carriers (NLCs) have been developed in order to improve cutaneous hydration. Due to its ultrafine particle size it is possible a film formation on the skin which decreases transepidermal water loss, improving occlusive effect and hydration. In this context, the aim of this work was to develop a formulation containing NLCs based in Ouratea sp. butter (Ochnaceae) as a strategy to increase cutaneous hydration. Firstly, it was performed a characterization of the components such as, stearic acid (SA), Ouratea sp. butter (OB), Phospholipon 90G®, and its physical mixtures by Differential Scanning Calorimetry (DSC), Thermogravimetry (TG) and X ray Diffraction (XRD). The NLCs were prepared using the diffusion solvent method and evaluated for particle size, polidispersity index, zeta potential, pH and conductivity. Moreover, NLCs were characterized by DSC, XRD and Transmission electron microscopy (TEM). Finally, the NLCs were incorporated into a cream base and were evaluated for rheological behavior, occlusive effect and potential cutaneous hydration in vitro. From the raw materials characterization was possible to observe in which the PM1 (SA + OB) 1:1 showed a slightly shift of the melting point corresponding to SA (57 to 50°C) and presented an amorphous portion at ~ 20° in the XRD analysis. These observations could be attributed to a decrease of crystallinity when compared with solid lipid pure, highly ordered. With the addition of Phospholipon® 90G (PM2), the melting point was highly shifted to lower temperature (57 to 34°C), and presented a pronounced amorphous at ~ 20° in XRD. Since the NLCs need to remain solid at room and body temperature, it is suggested that using a lower proportion of the Phospholipon® 90G in NLCs formulations. From the CMC determination of SDS surfactant (8,02 mmol L-1) was possible to suggest a range concentration of the SDS in the NLCs preparations. The formulation with the highest SDS concentration (24 mmol L-1) demonstrated the lowest size particle (~ 240 nm), however there were no difference in the zeta potential over formulation that using 10 mmol L-1 of SDS (~ -50 mV). The NLCs presented a decrease in the enthalpy (ΔHNLC8 = 22.2, ΔHNLC10 = 23.2, ΔHNLC24 = 7.2 J/g) and also an increase in the width peak when compared with solid lipid SA pure (ΔHSA = 164.1). In addition, the XRD analysis demonstrated that NLCs presented main peaks both formulations are similar to those found in the SA (23.93°, 25.09°, 27.98°), but with a lower intensity. These observations suggest a lipid matrix less ordered which result in NLC formation. TEM results confirmed previous data related to NLCs particle size (200 to 300 nm). After the incorporation of the NLC10 into a cream base, it was possible to observe an increase in the occlusive effect and potential cutaneous hydration. Therefore, NLCs containing Ouratea sp. butter can be an attractive nanotechnology way to increase cutaneous hydration. / Carreadores Lipídicos nanoestruturados (CLNs) têm sido desenvolvidos visando uma melhor hidratação cutânea. Devido ao seu reduzido tamanho de partícula, há formação de um filme sobre a pele o qual diminui a perda de água transepidermal, aumentando a hidratação. Neste contexto o objetivo deste trabalho foi desenvolver uma formulação contendo CLNs à base de manteiga de Ouratea sp. (Ochnaceae) como uma estratégia para o aumento do efeito oclusivo e da hidratação cutânea. Primeiramente foi realizada a caracterização das matérias-primas como, ácido esteárico (AE), Manteiga Ouratea sp.(MO), Phospholipon 90G® e suas misturas físicas utilizando Calorimetria Exploratória Diferencial (DSC), Termogravimetria (TG) e Difração de raios-X (DRX). Os CLNs foram preparados pelo método de difusão do solvente e avaliados por diâmetro médio de partícula, índice de polidispersão, potencial zeta, pH e condutividade. Os CLNs ainda foram caracterizados por DSC e DRX, Microscopia eletrônica de Transmissão (MET). Por fim, os CLNs foram incorporados no creme base e foram avaliados quanto ao comportamento reológico, efeito oclusivo e potencial hidratação cutânea in vitro. Através da caracterização das matérias-primas foi possível observar que a MF1 (AE + MO) 1:1 mostrou um pequeno deslocamento do ponto de fusão correspondente ao AE (57 a 50°C) e apresentou uma porção amorfa em ~ 20° nas análises de DRX. Essas observações podem ser atribuídas à diminuição da cristalinidade quando comparado com o lipídeo sólido puro, altamente ordenado. Com a adição do Phospholipon 90G® (MF2), o ponto de fusão foi deslocado para uma temperatura menor (57 a 34°C), e apresentou uma pronunciada porção amorfa em ~ 20° no DRX. Partindo do pressuposto que os CLNs devem se manter sólidos a temperatura ambiente e corpórea, é sugerida a utilização de uma menor proporção de Phospholipon® 90G nas formulações de CLNs. A partir da determinação da CMC do tensoativo SDS (8,02 mmol L-1) foi possível sugerir uma faixa de concentração de SDS nas preparações de CLNs. A formulação com a maior concentração de SDS (24 mmol L- 1) demonstrou o menor diâmetro de partícula (~ 240 nm), entretanto, não houve diferenças no potencial zeta em relação a formulação em que foi utilizado 10 mmol L-1 of SDS (~ -50 mV). CLNs apresentaram uma diminuição nos valores de entalpia (ΔHCLN8 = 22,2; ΔHCLN10 = 23,2; ΔHCLN24 = 7,2 J/g) e também um aumento da largura do pico quando comparados com o AE puro (ΔHSA = 164,1). Além disso, as análises de DRX demonstraram que os CLNs apresentaram picos principais similares àqueles encontrados no AE (23,93°; 25,09°; 27,98°), porém com uma menor intensidade. Os resultados de MET confirmaram os dados de diâmetro médio de partícula dos CLNs (200 a 300 nm). Após a incorporação do CLN10 no creme base, foi possível observar um aumento no efeito oclusivo e na hidratação cutânea. Dessa forma os CLNs contendo manteiga de Ouratea sp. podem ser uma alternativa nanotecnológica atrativa para o aumento da hidratação cutânea.
3

Metab?litos especiais isolados de folhas e galhos de Ouratea ferruginea Engl. (Ochnaceae).

Fidelis, Queli Cristina 25 February 2011 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2016-07-27T13:08:18Z No. of bitstreams: 1 2011 - Queli Cristina Fidelis.pdf: 8250271 bytes, checksum: f51d246c251bca4327f02da1e892ff77 (MD5) / Made available in DSpace on 2016-07-27T13:08:18Z (GMT). No. of bitstreams: 1 2011 - Queli Cristina Fidelis.pdf: 8250271 bytes, checksum: f51d246c251bca4327f02da1e892ff77 (MD5) Previous issue date: 2011-02-25 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico, CNPq, Brasil. / This work describes the phytochemical study of the stems and leaves of Ouratea ferruginea Engl., Ochnaceae. The material for study was collected in the campus of Embrapa in Bel?m, Par? state, and identified by Dra Silvane Taveres Rodrigues. The compounds described in this phytochemistry investigation were isolated by the solvents partition and chromatographyc techniques of the extracts obtained by maceration at room temperature with hexane, ethyl acetate and methanol. The structures were determined through analysis of data provided by IR, 1H and 13C NMR (1D an 2D techniques), mass spectrometry including GCMS and HPLC-MS of natural compounds and some derivatives. From the stem dichloromethane extract friedelin, friedelinol, sitosterol, stigmasterol, campesterol, 3-b-O-Dglucopyranosyl- stigmasterol, 2,6-dimethoxy?benzoquinine, 2,6-dimethoxy-hydroquinone, the isoflavones: 5,4'-dihydroxy-7,3',5'-trimethoxy-isoflavone, 5-hydroxy-7,3',4',5'-tetramethoxyisoflavone, 5,4'-dihydroxy-7,3'-dimethoxy-isoflavone, 7,5-dihydroxy-3',4',5'-trimethoxyisoflavone, 7,5,4?-trihydroxy-3?,5?-dimethoxy-isoflavone, and ferulic and syringic aldehyde were isolated. From the dichloromethane partition of the methanol extract of the stem vanillic acid, 4 ((1E)-3-hydroxy-1-propenyl)-2-methoxyphenol and 3,5-dimethoxy-4-hydroxydihydrocinamaldehyde were isolated. From hexane fraction of methanol extract from the leaves lupeone was isolated, and from the dichloromethane methanol partition were identified the biflavonoids amentoflavone and 7-methyl-amentoflavone, known as sequoiaflavone, along with syringic acid. From the ethyl acetate of the methanol extracts partition the epicatechin which absolute configuration was defined by circular dichroism spectral analysis was isolated. The sequioflanove is been identified in Ochnaceae for the first time. From the polar fraction the total phenol were determined by adapted Folin-Denis and precipitation with casein methods and by NMR spectral analysis. / Este trabalho descreve o estudo fitoqu?mico de caule e folhas da esp?cie vegetal Ouratea ferruginea Engl, Ochnaceae. O material para estudo foi coletado no campus da Embrapa em Bel?m do Par? e identificado pela Dra Silvane Tavares Rodrigues. As subst?ncias descritas nesta investiga??o fitoqu?mica foram isoladas atrav?s de parti??o com solventes e t?cnicas cromatogr?ficos de extratos obtidos atrav?s de macera??o a frio com hexano, acetato de etila e metanol. As estruturas foram determinadas atrav?s da an?lise de dados fornecidos por espectrometria na regi?o do infravermelho, RMN 1H e 13C (t?cnicas 1D e 2D), de massas incluindo CG-EM e CLAE-EM das subst?ncias naturais e de alguns derivados. Do extrato em diclorometano do caule foram isolados friedelina, friedelinol, sitosterol, estigmasterol, campesterol, 3-b-O-D-glicopiranosil-estigmasterol, 2,6-dimetoxi benzoquinona, 2,6-dimetoxi hidroquinona, as isoflavonas 5,4?-diidroxi-7,3?,5?-trimetoxiisoflavona, 5,4?-diidroxi-7,3?-dimetoxi-isoflavona, 5-hidroxi-7,3?,4?,5?-tetrametoxiisoflavona, 7,5-diidroxi-3?,4?,5?-trimetoxi-isoflavona, 7,5,4?-triidroxi-3?,5?-dimetoxiisoflavona, al?m dos alde?dos sir?ngico e fer?lico. Da parti??o em diclorometano do extrato metan?lico do caule foram isolados ?cido van?lico, 4((1E)-3-hidroxi-1-propenil)-2- metoxifenol e 3,5-dimetoxi-4-hidroxi-diidrocinamalde?do. Das folhas foi isolada a lupeona na parti??o em hexano do extrato metan?lico; e na parti??o em diclorometano foram identificados os biflavon?ides amentoflavona e 7-metil-amentoflavona, conhecida como sequoiaflavona, e o ?cido sir?ngico. Na parti??o em acetato de etila foi isolado a epicatequina cuja configura??o absoluta foi definida com an?lise do espectro de dicro?smo circular. A sequioflavona est? sendo registrada pela primeira vez em Ochnaceae. Das fra??es polares foram determinados o teor de fen?is totais e taninos por m?todos de Folin-Denis e precipita??o com case?na, adaptados, al?m de an?lise com espectros de RMN.
4

Bioprospecção para compostos antimicobacterianos

Cardoso, Franciano Dias Pereira 18 September 2017 (has links)
A tuberculose representa um sério problema de saúde pública, com alta taxa de incidência, surgimento de formas multirresistentes e difícil tratamento. Torna-se necessário o desenvolvimento de novos compostos e as plantas são fontes destes recursos. O cerrado é possuidor de uma grande biodiversidade e detém potencial em conter espécimes com alguma atividade biológica. Neste estudo objetivou-se a execução de ensaios laboratoriais, a fim de determinar a atividade antimicobacteriana envolvendo dez extratos brutos de plantas presentes neste bioma: Plathymenia reticulata, Ouratea spectabilis, Galactia glaucescens, Apuleia molaris, Dipteryx alata, Brosimum gaudichaudii, Tabebuia caraíba, Pterodon emarginatus, Terminalia fagifolia e Stachytarpheta sp. Os resultados da pesquisa demonstraram que os extratos hidroalcoólicos de O. spectabilis e A. molaris tiveram expressivas concentrações inibitórias para Mycobaterium tuberculosis e demonstraram baixa toxicidade frente as células LLC-MK2 e Vero. O fracionamento dessas duas amostras, relevou uma fração hexânica da A. molaris com significativa ação farmacológica frente a cepas H37Rv, sendo caracterizada como possuidora de compostos promissores para futuros ensaios envolvendo atividade antituberculose. / Tuberculosis represents a serious public health problem, with a high incidence rate, the emergence of multiresistant forms and difficult treatment. It is necessary to develop new compounds and plants are sources of these resources. The Brazilian savanna vegetation has a great biodiversity and holds the potential to contain specimens with some biological activity. The objective of this study was determined the antimycobacterial activity involving ten crude extracts of plants present in this biome: Plathymenia reticulata, Ouratea spectabilis, Galactia glaucescens, Apuleia molaris, Dipteryx alata, Brosimum gaudichaudii, Tabebuia caraíba, Pterodon Emarginatus, Terminalia fagifolia and Stachytarpheta sp. The results of the research demonstrated that the hydroalcoholic extracts of O. spectabilis and A. molaris had significant inhibitory concentrations for Mycobaterium tuberculosis and showed low toxicity against LLC-MK2 and Vero cells. The fractionation of these two samples revealed a hexanic fraction of A. molaris with significant pharmacological action against H37Rv, being characterized as having promising compounds for future trials involving antituberculosis activity.
5

Imunomodula??o e a??o anti-Leishmania (Viannia) braziliensis por Ouratea cuspidata (Ochnaceae) / Immunomodulation and action anti-Leishmania (Viannia) braziliensis promastigotes by Ouratea cuspidata (Ochnaceae)

Ribeiro, Renata da Silva 27 February 2007 (has links)
Made available in DSpace on 2016-04-28T20:15:26Z (GMT). No. of bitstreams: 1 2007-Renata da Silva Ribeiro.pdf: 705558 bytes, checksum: e16373fa17f99c734d58ede2a54543c6 (MD5) Previous issue date: 2007-02-27 / Ouratea cuspidata (Ochnaceae) crude extracts were added to experimental systems containing either host macrophages, or Leishmania braziliensis promastigotes (L566). The biological effect by the use of the hexane (OCH), methanol (OCMeH) and ethyl-acetate (OCAcEt) extracts added at different concentrations: 2mg/mL; 4mg/mL; 8mg/mL, 16mg/mL e 32mg/mL. The OCMeOH was the only fraction to which the anti parasitic potentiality was achieved at doses rates that generated bio protective effects in the host cells. The parasiticide action, due by direct exposure of promastigotes to OCMeOH, as well as the parasitic growth, and morphological alterations intermediary metabolism alterations (mitochondrial activity) were concomitantly measured. Biological macrophagic functions were also evaluated using Cricetus cricetus peritoneal macrophages as a model (Mf). Bio-protective assays were carried out in order to determine the free radical generation by the extract constituents. The results were compared with non treated L566 and Mf. 78% of the 16 mg/106 Mf/mL treated Mf were viable but a significant decrease of their phagocytosis capability (92%) was detected. Such alterations were evident in 62% of the cells treated with 32mg/106 Mf/mL. At this concentration cells were 70% viable and presented 98% phagocytosis suppression. The macrophages enzymatic- mitochondrial activity was gradually diminished, with 87% activity at exposures to 8mg/106 Mf/mL; 66,3% at exposures to 16mg/106 Mf/mL, and 49% at exposures to 32mg/106 Mf/mL, respectively. The anti parasitic effects were not associated to the promastigotes lack of viability. Instead, a significant rising on the L566 cells counting was detected when compared to control non treated parasites, from the first 6 hours treatment until 24 hours exposure. Morphological changes were detected in 62% of the 8mg/106 L566/mL parasite treated cells; 78% after 16mg/106 L566/mL treatment, and 98% of the cells presented morphological changes after 32mg/106 L566/mL treatment. Cells were either round-shaped, showing incomplete mitosis, or presenting double flagella, suggesting that the present extract containing substances that might interfere in the parasitic topoisomerase function. The parasitary mitochondrial activity evidenced the occurrence of a metabolic acceleration due by the OCMeOH treatment. The mitochondrial enzymatic activity was of 220% at exposures to 8mg/106 L566/mL; 389% at exposures to 16mg/106 L566/mL and of 480% at exposures to 32mg/106 L566/mL, respectively, when compared to the non treated parasites (100%). The anti parasitic potential (Therapeutic Index) was considered to be positive (acceptable) (TI=4,0) when estimated in function of the morphological changes observed at the extract concentration of 32mg/106 Mf/mL (LD62%), and at 8mg/106 L566/mL (ED62%), respectively. Since bi-flavonoids are the main constituents present in the OCMeOH, results were suggestive the anti parasitic effect was due to this group of secondary metabolites. As such biologically active molecules are known COX2 selective inhibitors, its internal use should be avoided. Otherwise, bi- flavonoids are good candidate substances to be applied as topical medicine to treat the American Tegumentar Leishmaniasis. / Os efeitos dos extratos de Ouratea cuspidata (Ochnaceae) foram avaliadas a partir da exposi??o de c?lulas hospedeiras e de promastigotas de Leishmania (Viannia) braziliensis (L566) ?s fra??es oriundas da sua parti??o hex?nica (OCH), metan?lica (OCMeOH) e acetato de et?lica (OCAcEt). Dentre estas, a fra??o OCMeOH foi a ?nica que apresentou potencial antiparasit?rio em doses que geraram bioprote??o aos sistemas hospedeiros. Assim, procederam-se an?lises de a??o parasiticida direta do extrato OCMeOH sobre formas promastigotas, onde, tamb?m, foram avaliados o crescimento, altera??es morfol?gicas e fun??es do metabolismo mitocondriais. Do mesmo modo, foram realizadas observa??es semelhantes em macr?fagos peritoneais de hamsters Cricetus cricetus (Mf) afim de se determinar a toxicidade relativa para o hospedeiro. Finalmente, foram realizados ensaios complementares de bioprote??o e gera??o de radicais livres, com a finalidade de confirmar a poss?vel aplica??o terap?utica dos constituintes presentes no extrato. Em todas as etapas experimentais, foram utilizadas cinco concentra??es de OCMeOH (2mg/mL; 4mg/mL; 8mg/mL; 16mg/mL e 32mg/mL), sendo que os resultados obtidos foram comparativamente avaliados em rela??o a sistemas de controle (L566 e Mf n?o tratados). Os (Mf) tratados com 16 mg/106 Mf/mL do extrato sofreram uma diminui??o significativa (92%) de sua capacidade fagocit?ria, mas permaneceram vi?veis, em sua maioria (78%). As altera??es morfol?gicas mostraram-se mais evidentes em 62% das c?lulas tratadas com 32mg/106 Mf/mL, com 70% de viabilidade e 98% de inibi??o da fagocitose. A atividade enzim?tica-mitocondrial macrof?gica apresentou diminui??o gradativa, com a preserva??o de 87% das fun??es enzim?ticas nas c?lulas tratadas com 8mg/106 Mf/mL; 66,3% daquelas tratadas com 16mg/106 Mf/mL e 49% das tratadas com 32mg/106 Mf/mL. As L566 n?o apresentaram a perda da viabilidade ap?s exposi??o de 24horas ?s diferentes concentra??es de OCMeOH. Ao contr?rio, houve um aumento significativo no n?mero de promastigotas que, a partir de seis horas de cultivo, mostraram-se sempre superiores ? quantidade de parasitos n?o tratados. Foram detectadas altera??es morfol?gicas em 62% das L566 tratadas com 8mg/106 L566/mL; 78% daquelas tratadas com 16mg/106 L566/mL e 98% das tratadas com 32mg/106 L566/mL. As promastigotas tratadas apresentaram-se arredondadas, com mitose incompleta, ou apresentando dois flagelos, sugerindo que as subst?ncias presentes no extrato podem interferir nas topoisomerases parasit?rias. A atividade mitocond rial parasit?ria evidenciou a ocorr?ncia de acelera??o metab?lica induzida pelo tratamento com OCMeOH. A atividade enzim?ticamitocondrial foi de 220% no tratamento com 8mg/106 L566/mL; de 389% com 16mg/106 L566/mL e 480% com 32mg/106 L566/mL quando comparadas ao controle (100%). O potencial antiparasit?rio (Indice Terap?utico) foi considerado positivo (IT=4,0) em fun??o das altera??es morfol?gicas observadas nas concentra??es de 32mg/106 Mf/mL (LD62%), e 8mg/106 L566/mL (ED62%). Sendo biflavon?ides os constituintes presentes em maior propor??o, atribuiu-se a este grupo de subst?ncias a a??o antiparasit?ria e imunot?xica observadas para OCMeOH. Os bi-flavon?ides presentes no extrato metan?lico de Ouratea cuspidata est?o entre os inibidores seletivos de COX2, sugerindo o desenvolvimento de pesquisas que visem sua utiliza??o t?pica em animais naturalmente infectados.
6

Avaliação da eficiência da espécie vegetal ouratea parviflora como inibidor de corrosão em aço carbono

Neri, Renaly dos Santos 31 January 2018 (has links)
Submitted by Automação e Estatística (sst@bczm.ufrn.br) on 2018-07-02T22:06:25Z No. of bitstreams: 1 RenalyDosSantosNeri_DISSERT.pdf: 2881911 bytes, checksum: 90ca65b55d05f94be7a653e8337ad53d (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2018-07-09T12:33:06Z (GMT) No. of bitstreams: 1 RenalyDosSantosNeri_DISSERT.pdf: 2881911 bytes, checksum: 90ca65b55d05f94be7a653e8337ad53d (MD5) / Made available in DSpace on 2018-07-09T12:33:06Z (GMT). No. of bitstreams: 1 RenalyDosSantosNeri_DISSERT.pdf: 2881911 bytes, checksum: 90ca65b55d05f94be7a653e8337ad53d (MD5) Previous issue date: 2018-01-31 / Conselho Nacional de Desenvolvimento Científico e Tecnológico - CNPq / Os impactos da corrosão são frequentes e ocorrem nas mais variadas atividades. Existem diversas formas de combater a corrosão, dentre elas se destaca o uso de microemulsões que vêm sendo alvo de interesse como inibidores de corrosão. Apesar de eficientes no controle da corrosão, alguns inibidores possuem elevado custo, além disso, a grande maioria é tóxica ao meio ambiente, tornando seu uso questionável. De modo à atender a demanda por inibidores de corrosão em aço carbono, este trabalho teve como objetivo a investigação da ação inibitória do óleo das amêndoas e do extrato hidroalcoólico das folhas da espécie vegetal Ouratea Parviflora. O extrato hidroalcoólico foi avaliado de forma livre e em sistema microemulsionado, contendo o óleo das amêndoas em sua composição, utilizando diferentes concentrações, como inibidores de corrosão em meio salino (NaCl 3.5%). Foi utilizado o método eletroquímico de Resistência de Polarização Linear, determinando-se também o comportamento e a isoterma do processo de adsorção metal/inibidor. De acordo com os resultados, as eficiências máximas de inibição foram de 67.70% (12,5 ppm), 77.94% (200 ppm) e 85.66% (200 ppm) para o extrato hidroalcoólico, sistema microemulsionado salino (SME-S) e sistema microemulsionado salino com adição do extrato hidroalcoólico (SME-S-EB), respectivamente. Quanto ao processo de adsorção, os dados experimentais se ajustaram a isoterma de Langmuir. De acordo com os dados calculados de energia livre de Gibbs foi detectada a espontaneidade com que os inibidores utilizados em diferentes condições se adsorveram sobre a superfície do aço carbono. O estudo da obtenção dos inibidores utilizados em diferentes condições sob o viés da sustentabilidade confirmou que estas formulações podem ser consideradas como sustentáveis. Os resultados mostraram que o extrato hidroalcoólico de Ouratea parviflora avaliado de forma livre e em sistema microemulsionado, contendo o óleo das amêndoas da mesma espécie vegetal, podem ser utilizados como fontes alternativas na formulação de inibidores de corrosão. / The impacts of corrosion are frequent and occur in various activities. There are several ways of combating impacts, among them the use of micro-emulsified system have been targeted as corrosion inhibitors. Although they are effective in the corrosion control, some have high cost and are toxic to the environment, making its use questionable. In order to fulfill the growing demand for corrosion inhibitors, the objective of the present work was to perform a research about the inhibitory action of almonds oil and hydro-alcoholic extract from vegetal specie Ouratea parviflora. The extract was evaluated in free formand in a microemulsified system, containing the oil of the almonds in your composition, with different concentrations, regarding the corrosion inhibition efficiency into a saline medium (NaCl 3.5%). Was used the method Linear Polarization Resistance method, also determining the behavior and the isotherm of the metal/inhibitor adsorption process. According to the obtained results, the maximum inhibition efficiencies were observed at 67.70% (12.5 ppm), 77.94% (200 ppm) and 85.66% (200 ppm) to the free hydro-alcoholic extract, saline microemulsified system (SME-S) and saline micro-emulsified system with extract (SME-S-EB), respectively. In addition, all the experimental data from the adsorption process fitted the Langmuir isotherm. According to the data calculated from Gibbs free energy, it was detected a spontaneity of the adsorbent inhibitors used in different conditions on the steel surface. The study of getting of inhibitors used in different conditions under the sustainability bias confirmed that these formulations can be considered as sustainable. The results showed that the hydro-alcoholic extract of Ouratea parviflora evaluated in free form and in a microemulsion system containing the oil of the almonds of the same plant species, can be used as alternative sources in the formulation of corrosion inhibitors.
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Atividade antibacteriana, antioxidante e citotóxica in vitro do extrato etanólico da entrecasca da planta Ouratea hexasperma (EEEOH) (A. St-Hil.) Baill var. Planchonii Engl

COSTA, Glauber Vilhena da 17 September 2015 (has links)
Submitted by Cássio da Cruz Nogueira (cassionogueirakk@gmail.com) on 2017-01-30T13:56:51Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) DISSERTAÇÃO GLAUBER VILHENA.pdf: 2944304 bytes, checksum: 8136050f001efa001db56b7d8326012a (MD5) / Approved for entry into archive by Edisangela Bastos (edisangela@ufpa.br) on 2017-02-01T12:01:17Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) DISSERTAÇÃO GLAUBER VILHENA.pdf: 2944304 bytes, checksum: 8136050f001efa001db56b7d8326012a (MD5) / Made available in DSpace on 2017-02-01T12:01:17Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) DISSERTAÇÃO GLAUBER VILHENA.pdf: 2944304 bytes, checksum: 8136050f001efa001db56b7d8326012a (MD5) Previous issue date: 2015-09-17 / Ouratea hexasperma (Ochnacea), popularmente conhecida como “barbatimão do cerrado”, é uma planta muito comum na região do cerrado brasileiro e, vem sendo utilizada para o tratamento de infecções microbianas e inflamações. Por isso, este estudo teve como objetivo avaliar as atividades antioxidante, quantificar teores flavonoides totais (TFT), antibacteriana e citotoxicidade do extrato etanólico da entrecasca da Ouratea hexasperma (EEEOH), bem como realizar sua caracterização fitoquímica. A planta foi coletada no estado do Amapá e em seguida foi realizada extração da entrecasca seca através de maceração à frio com solução etanólica 96% na proporção 2:8 (p/v) durante 1 dia, formando o EEEOH. A caracterização fitoquímica foi realizada através de ensaios cromáticos/precipitação em tubo e o teor de flavonoides foi mensurado através do ensaio com complexação com alumínio utilizando como padrão uma curva de quercetina (40–0,62μg/mL), e a capacidade antioxidante total através do método espectrofotométrico de descoloração do radical ABTS•+ (2,2´azino-bis-3-etilbenzotiazolin 6-ácido sulfônico) - TEAC. A atividade antimicrobiana do EEEOH foi testada frente às bactérias gram-positivas e gram-negativas, através das técnicas de microdiluição em caldo com coloração por resazurina, para a determinação da Concentração Inibitória Mínima (CIM), e de cultivo em placa de petri com posterior contagem das unidades formadoras de colônias (UFC) para a obtenção da Concentração Bactericida Mínima (CBM). A citotoxicidade do EEEOH, foram testadas utilizando leucócitos humanos do sangue periférico, células mononucleares, com diferentes concentrações do extrato e sem nenhum estímulo (controle negativo), e incubação e mantidos a 37ºC, 98% de umidade e 5% de CO2, durante 24h, NO e MDA foram lidas de ELISA e espectrofotômetro em diferentes leituras óticas. A análise fitoquímica preliminar do EEEOH mostrou a presença de taninos, saponinas e flavonóides. O TFT no extrato foi de 1467 ± 264μg equivalentes em quercetina/g de EEEOH. A capacidade antioxidante pelo método de TEAC apresentaram elevada atividade antioxidante, não havendo diferença na capacidade antioxidante (TEAC) entre as concentrações do extrato testadas. O EEEOH apresentou boa ação antibacteriana, principalmente contra as bactérias gram-positivas. Na citotoxicidade por regressão linear se obteve a concentração capaz de matar 50% das células (CC50%), cujo valor foi de 2231,5mg/mL, confirmando que o extrato bruto tem baixa citotoxicidade frente a leucócitos humanos, nas condições testadas. Na produção de NO e MDA verificou-se que o EEEOH não foi capaz de induzir a produção de NO das concentrações testadas. Como também, nenhuma concentração induziu aumento de MDA quando comparado ao controle negativo (RPMI), confirmando a baixa citotoxicidade do extrato in vitro. As análises estatísticas foram realizadas pelo teste Anova uma via e Turkey. Conclui-se que EEEOH possui atividade antibacteriana, antioxidante e baixa citotoxicidade. / Ouratea hexasperma (Ochnacea), popularly known as "cerrado barbatimão" is a very common plant in the brazilian cerrado region and has been used for the treatment of microbial infections and inflammation. Therefore, this study aimed to evaluate the antioxidant activities, quantifying total flavonoid content (TFT), antibacterial and cytotoxicity of ethanol extract of the bark of Ouratea hexasperma (EEBOH) as well as perform their phytochemical characterization. The plant was collected in the state of Amapá, and then was held extraction of dry bark through the cold maceration with 96% ethanol solution in a 2: 8 (w/v) for 1 day, forming the EEBOH. The phytochemical characterization was performed by testing chromatic/precipitation tube and flavonoid content was measured by assay complexation with aluminum using quercetin as standard (40-0,62μg/mL), and the total antioxidant capacity by the spectrophotometric method discoloration radical ABTS•+ (2,2'azino-bis-3-etilbenzotiazolin 6-sulfonic acid) - TEAC. The antimicrobial activity of EEBOH was tested against gram-positive and gram-negative bacteria, using the microdilution techniques broth with staining by resazurin, to determine the Minimum Inhibitory Concentration (MIC), and grown in petri dish with subsequent count of colony forming units (CFU) for obtaining the Minimum Bactericidal Concentration (MBC). The evaluation of the cytotoxicity of EEEOH human peripheral blood leukocytes. Mononuclear peripheral blood cells incubated with different concentrations of the extract and without stimulation (negative control). The cytotoxicity of EEEOH were tested using human peripheral blood leukocyte, mononuclear cells, with different extract concentrations and without stimulation (negative control), and incubated and maintained at 37 ° C, 98% humidity and 5% CO2 for 24 hours, NO and MDA were read in an ELISA spectrophotometer and different optical readings. The primary EEBOH phytochemical analysis showed the presence of tannins, saponins and flavonoids. The TFT in the extract was 1467 ± 264μg equivalents quercetin/g EEBOH. The antioxidant capacity by TEAC method showed high antioxidant activity, with no difference in antioxidant capacity (TEAC) between those concentrations of the extract. The EEBOH showed good antibacterial activity, mainly against gram-positive bacteria. The cytotoxicity was obtained by linear regression concentration able to kill 50% of cells (CC 50%) whose amount was 2231,5mg/mL, confirming that the crude extract has low cytotoxicity against human leukocytes, under the conditions tested. In the production of NO and MDA it found that the EEOC was not able to induce NO production of the concentrations tested. As well, no increase MDA of concentration induces changes when compared to the negative control (RPMI), confirming the low in vitro cytotoxicity of the extract. Statistical analyzes were performed by ANOVA one way and Turkey. In concluded that the EEBOH have antibacterial, antioxidant and low cytotoxicity.
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Conservation Strategies of the Red Listed Brackenridgea zanguebarica Oliv. in Vhembe District Municipality, Limpopo Province, South Africa

Tiawoun, Makuete Andre 20 September 2019 (has links)
PhD (Botany) / Department of Botany / Brackenridgea zanguebarica Oliv. (Ochnaceae) commonly known as “Yellow Peeling Plane”, is an important medicinal plant species, and one of the most threatened tree species that is endemic to Thengwe village in Vhembe District, South Africa. It is widely harvested for traditional purposes and difficult to propagate sexually and asexually. Nowadays, it has become threatened and this unique plant population is believed to be declining in the Brackenridgea Nature Reserve (BNR). According to the Red List of South African plants, B. zanguebarica is considered a critically endangered medicinal plant. All these facts combined with a lack of knowledge on the conservation of this species prompted this study on its conservation. To ascertain the effective conservation and proper management of this multipurpose tree, this study was conducted with the aim to improve its conservation strategy by investigating current threats to the existence of B. zangueberica, the chemical constituents from the different plant parts, the propagation methods of the species, and the factors delaying the germination of its seeds. In this study, an assessment of the current population threats was important as a first step in conservation; this would update the status of the species in its natural habitat. The current status of Brackenridgea zanguebarica was conducted through an extensive field survey in the Brackenridgea Nature Reserve (BNR), where a belt transect method was deployed to record quantitative information, while the harvesting damage was estimated using a sliding scale from 0 to 5. The structure of the populations in terms of the stem diameter size classes showed a bell shape vi pattern. About 60% of individuals showed some signs of plant parts extraction as the stem bark was reported to be the main plant part harvested. The population structure, however, was dominated by juvenile plants due to the selective harvesting of mature individuals; this hinders fruit production leading to poor or slow seed production. The present study aimed to compare the chemical constituents and the antimicrobial activities of some parts of this plant species. The extracts were screened for phytochemicals using standard methods. Thin-layer chromatography (TLC) was carried out to compare the chemical constituents using various solvent systems of varying polarity. Agar well diffusion and broth microdilution methods were used to evaluate the antimicrobial activity and the minimum inhibitory concentrations (MIC) of plant extracts respectively, against three bacteria and four fungi. The phytochemical analysis revealed a close similarity of various phytoconstituents of the three plant parts (stem bark, twigs and leaves). TLC analysis showed a slight difference in the acetone extract of different plant parts with more bands on the leaves than the stem bark and twigs. Acetone extracts of the three plant parts exhibited varying degrees of antimicrobial activity against Staphylococcus aureus and Candida glabrata, while none of the extracts showed any activity against Escherichia coli, Klebsiella pneumonia, Candida albicans, C. krusei, and C. parapsilosis. However, analysis of the antibacterial activity of various extracts revealed that the best inhibitory activity was produced by the stem bark extract compared to the leaf and twig extract. vii The sustainable way to meet the growing demand of Brackenridgea zanguebarica is to increase its availability through propagation practices. Unfortunately, the conservation of B. zanguebarica is hampered by lack of information on how it can be propagated. Sexual and asexual propagations were conducted to determine an efficient method to increase the number of individuals of this plant species. Seed propagation was carried out to study the effect of various pre-treatments on germination, in order to understand the germination requirements; vegetative propagation was conducted to assess if B. zanguebarica could be successfully propagated via stem cuttings if the appropriate growth hormones and growing media were applied. Brackenridgea zanguebarica seed did not germinate at all under any of the conditions tested. However, the results, showed the potential of propagating this species from stem cutting despite the poor results obtained. Thus B. zanguebarica was found to be difficult to propagate sexually and asexually. Seeds serve as a means of reproduction and a vital element to ensure the survival of plant species. Seed germination is controlled by a number of factors. The propagation of B. zanguebarica via seed is very difficult and research has not been undertaken to understand possible factors that may delay its germination. This study was aimed to investigate and describe both the morphological and anatomical features of B. zanguebarica seed, in order to identify structural features implicated in its poor germination. To achieve this goal, a morphological and anatomical study was conducted based on the observation of seeds under a scanning electron microscope (SEM) and light microscopy (LM). Water uptake potential was assessed by the increase in seed mass. The morpho-anatomical analysis indicated that some structures of the seed, such as seed coat, and the presence of endosperm viii surrounding the embryo that consisted of two prominent cotyledons, seem to greatly hinder the germination of this species. The research findings provided information regarding the seed structure which is one important step in identifying useful techniques to improve seed germination for conservation purposes. / NRF

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