999 resultados para Produtos naturais Teses
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Coordenao de Aperfeioamento de Pessoal de Nvel Superior (CAPES)
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Conselho Nacional de Desenvolvimento Cientfico e Tecnolgico (CNPq)
Produtos naturais no controle do caro Varroa destructor em abelhas Apis mellifera L. (africanizadas)
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Coordenao de Aperfeioamento de Pessoal de Nvel Superior (CAPES)
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Conselho Nacional de Desenvolvimento Cientfico e Tecnolgico (CNPq)
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As formigas cortadeiras, pertencentes aos gneros Atta e Acromyrmex, possuem esse nome pelo hbito que tm de cortar as folhas das plantas. Por este motivo, elas causam danos econmicos, principalmente em reas de cultura agrcola. Para realizar o controle dessas pragas, existem inmeros mtodos; porm, os nicos que apresentam resultados satisfatrios so os que utilizam inseticidas tradicionais. O controle qumico pode gerar efeitos malficos ao ambiente, fauna e populao humana. por isso que h uma grande procura por mtodos alternativos, utilizando produtos que tenham grande especificidade e sejam passveis de rpida degradao, sendo, portanto, menos danosos ao ambiente. Uma destas alternativas a utilizao de produtos naturais presentes nos vegetais superiores, que podem constituir novas fontes de material com ao txica para estes insetos praga. Este trabalho teve por objetivo avaliar a toxicidade das plantas Magonia pubescens e Duguetia lanceolata para operrias de Atta sexdens rubropilosa. Para os testes, as formigas foram divididas em lotes de 50 operrias, distribudas em 5 placas para cada tratamento e mantidas em B.O.D. durante os 25 dias do experimento. Nos bioensaios de ingesto, os extratos provenientes das plantas foram incorporados em dieta artificial e testados durante 25 dias. No bioensaio tpico, as substncias eram colocadas no pronoto das formigas e era oferecida dieta pura em todos os dias do experimento. Aps os testes, os dados foram transferidos para o software Prisma 3.0, para a confeco de curvas de sobrevivncia e para a realizao das anlises estatsticas. Apesar de Magonia pubescens apresentar um bom resultado, no foi possvel continuar com os testes, pois a alta polaridade dos extratos impossibilitava a separao das substncias... (Resumo completo, clicar acesso eletrnico abaixo)
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In this work were studied associations of ZnO with the natural products caffeic and feluric acids. Two preparation methods were used, that is, the sol-gel and a reflux procedure. In the sol-gel method, ZnO is produced by the basics hydrolysis of precursors in the presence of the organic filters (caffeic and feluric acids), which results in 30 nm (or less) ZnO particles with the organic filters (in dissociated form) bonded to the surface of ZnO. In the reflux method, a dispersion of ZnO in a water/ethanol mixture was kept under reflux (50oC/4h) in the presence of the organic acids. The ZnO particles used in the reflux method have a higher diameter than sol-gel ZnO particles, but the prepared associated product ZnO/Organic acids were similar. Despite of the difference in relation to crystallinity between the products, the preparation methods resulted in analogous associations with respect to the interaction of the organic filters with the ZnO surface. The caffeic/ZnO associations presented low photostability, which lead to the degradation of the organic filter. The other associations (feluric acid/ZnO) presented satisfactory results. The FT-IR spectroscopy confirmed the formation of the association, and the nature of the bond formed compared with the Zn-O bond in Zn2+/Felutic acid complexes. The isolated organic and inorganic filters, along with the associations were analyzed by diffuse reflectance spectroscopy and Uv-vis spectroscopy. The absorption edges and the critical wavelengths were analyzed and the effects of Zn-O bonds in feluric acid/ZnO associations described as a function of the relative position of the /* system of the organic filter. Finally the performance of the hybrid filters were investigated in terms of the absorption of UVA and UVB radiations, with the UVA/UVB ratio, an efficiency parameter largely used in the description of solar filters, sunscreen and suncare products
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The interest in the use of evaporative light scattering detector (ELSD) for the analysis of different classes of natural products has grown over the years. This is because this detector has become an excellent alternative compared to other types of detectors, such as the refractive index detector and the ultraviolet (UV) detector. This review describes the basic principles of ELSD functioning and discusses the advantages and disadvantages in using an ELSD for the analysis of organic compounds. Additionaly, an overview, covering the last 23 years, of ELSD applications in natural products analysis (saponins, terpenes, carbohydrates, glycosides, alkaloids, steroids, flavonoids, peptides, polyketides, coumarins and iridoids) is presented and discussed.
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The biofilms microbial forms of association are responsible for generating, accelerating and / or induce the process of corrosion. The damage generated in the petroleum industry for this type of corrosion is significatives, representing major investment for your control. The aim of this study was to evaluate such tests antibiograms the effects of extracts of Jatropha curcas and essential oil of Lippia gracilis Schauer on microrganisms isolated from water samples and, thereafter, select the most effective natural product for further evaluation of biofilms formed in dynamic system. Extracts of J. curcas were not efficient on the complete inhibition of microbial growth in tests type antibiogram, and essential oil of L. gracilis Schauer most effective and determined for the other tests. A standard concentration of essential oil of 20 μL was chosen and established for the evaluation of the biofilms and the rate of corrosion. The biocide effect was determined by microbial counts of five types of microorganisms: aerobic bacteria, precipitating iron, total anaerobic, sulphate reducers (BRS) and fungi. The rate of corrosion was measured by loss of mass. Molecular identification and scanning electron microscopy (SEM) were performed. The data showed reduction to zero of the most probable number (MPN) of bacteria precipitating iron and BRS from 115 and 113 minutes of contact, respectively. There was also inhibited in fungi, reducing to zero the rate of colony-forming units (CFU) from 74 minutes of exposure. However, for aerobic and anaerobic bacteria there was no significant difference in the time of exposure to the essential oil, remaining constant. The rate of corrosion was also influenced by the presence of oil. The essential oil of L. gracilis was shown to be potentially effective
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Os avanos das pesquisas em biotecnologia e as transformaes recentes no perfil dos mercados de consumo tm propiciado novas oportunidades para diversos segmentos industriais contemporneos e uma das inovaes representativas desses processos est associada ao desenvolvimento de produtos cosmticos derivados de ativos naturais da biodiversidade. Sob essa perspectiva, algumas experincias internacionais tm se destacado no mercado mundial de cosmticos justamente pelo seu pioneirismo e liderana nessa modalidade de inovao, como o caso do segmento desenvolvido na Frana. Dessa forma, o trabalho tem como objetivo identificar nesse pas as principais etapas da cadeia produtiva dos cosmticos de origem vegetal, desde a produo das matrias-primas e produtos acabados, como tambm o desempenho comercial do setor, as novas exigncias de certificao, dentre outros. A interpretao e as anlises dos processos dominantes so feitas segundo o levantamento e a organizao das informaes de origem primria obtidas nos trabalhos de campo e dos indicadores secundrios. A fim de ilustrar alguns dos seus principais circuitos produtivos, foi selecionado um grupo representativo de indstrias, associaes de produtores e centros de pesquisa localizados na regio de Provence-Alpes-Cte dAzur.
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Conselho Nacional de Desenvolvimento Cientfico e Tecnolgico (CNPq)
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Jornadas "Cincia nos Aores que futuro?", Ponta Delgada, 7-8 de Junho de 2013.
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O uso de fluidos supercrticos na extrao de produtos naturais tem-se mostrado como uma potencial tecnologia, apresentando inmeras vantagens em relao extrao com solventes comuns. Nos processos envolvendo produtos naturais incluem-se desde aplicaes implantadas em nvel comercial, como a descafeinizao do caf, at investigaes a nvel laboratorial, tais como a extrao de princpios ativos de produtos naturais (como, por exemplo, alcalides) e encapsulamento de agentes quimioteraputicos pela cristalizao a partir de misturas supercrticas e/ou a utilizao de fluidos supercrticos como anti-solventes. Objetivando o levantamento de subsdios experimentais e tericos que contribuam para o desenvolvimento cientfico desta promissora tecnologia no Brasil, o Laboratrio de Engenharia de Processos de Produtos Naturais do Departamento de Termofluidodinmica da Faculdade de Engenharia Qumica da UNICAMP vem se dedicando, nos ltimos quatro anos, ao estudo da extrao de princpios ativos e do fracionamento de produtos de ocorrncia natural utilizando fluidos supercrticos. Neste trabalho, apresenta-se uma exposio das atividades e os resultados obtidos por este grupo de pesquisa na rea de extrao e fracionamento de produtos de ocorrncia natural.
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This study has as objective determining the chemical properties that serve as the basis for potential scientific and technological applications of seven species of fibrous plants cultivated in Brazil, which are: Banana (Musa spp.), Coco (Cocos nucifera), Curau (Ananas erectifolius), Fique (Furcraea andina), Piteira (Furcraea gigantea), Sisal(Agave sisalana) and Taboa (Typha domingensis). The tests for determining the percent dry completely, extractives soluble in cold water, in hot water, in sodium hydroxide 1% and in ethanol-toluene, and the percentages of ash, hydrophobicity, lignin, holocellulose and cellulose were performed at the Department of Environmental Sciences, Agronomy College (FCA) of UNESP Botucatu, So Paulo State. It also presents a literature review about these fibers and their potential applications. Differences between the results obtained and those found by other authors are possibly explained by variations on the origin of plant material, the harvest season, the climate and soil where they were grown. However, the results and the methodology used, serve as a basis for further studies with natural fibers
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Ps-graduao em Agronomia - FEIS