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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

Extra??o supercr?tica de Lycopodium Clavatum L.

Silva, Graciane Fabiela da 10 January 2014 (has links)
Made available in DSpace on 2015-04-14T13:59:03Z (GMT). No. of bitstreams: 1 453266.pdf: 4427206 bytes, checksum: 875df6097aa0d8c0eb37b5aefb426750 (MD5) Previous issue date: 2014-01-10 / The Lycopodium genus plants contain secondary metabolites that make them a potential source of pharmacologically active compounds. The extract of the specie Lycopodium clavatum L. presents anticholinesterase, anti-inflammatory, antibacterial, antiviral and antifungal activities. The supercritical fluid extraction has several advantages compared to traditional extraction techniques. Therefore, this study aimed metabolites Lycopodium clavatum L. extraction thru supercritical CO2 process. The supercritical fluid pressure and temperature as well the pretreatment time (soaking the plant in basic solution) influences in lycopodine alkaloid content in the extract were evaluated by an incomplete factorial design with three factors and three levels (Box-Behnken) and response surface methodology. The extract was subjected to Stas-Otto acid-base process and then analyzed by mass spectrometry coupled gas chromatography. The content of lycopodine was defined by normalizing peak areas of the chromatogram. The pressure was evaluated between 200 and 300 bar, the temperature between 40 to 60?C and the immersion time was zero to two hours. Oniy pressure and temperature were statistically significant, for this reason they are ideal parameters for extraction: 300 bar, 40?C, without immersion of the plant in the alkaline solution. Under these conditions we obtained a content of 20.19% of lycopodine the final extract was raised and the yield curve as a function of extraction time. This curve was modeled mathematically, with good fit, for models of Crank (1975), Sovov? (1994) and Reverchon (1996). Thus parameters related the mass transfer were estimated such as difusion coefficient and mass transfer coefficient, which are important for scale-.up and process simulation. In this study, the extraction with supercritical CO2 was found toe technically feasible to obtain lycopodine, since it is more selective and with higher yields compared to the ethanol extraction case. / Plantas do g?nero Lycopodium cont?m metab?litos secund?rios que as tornam uma potencial fonte de compostos farmacologicamente ativos. O extrato da esp?cie Lycopodium clavatum L. apresenta atividade anticolinester?sica, anti-inflamat?ria, antibacteriana, antiviral e antif?ngica. A extra??o com fluido supercr?tico, frente a t?cnicas tradicionais de extra??o, apresenta diversas vantagens quando aplicada a diferentes esp?cies vegetais. Assim, o presente estudo teve por objetivo a aplica??o do processo com CO2 supercr?tico para a extra??o de metab?litos da Lycopodium clavatum L. Foram avaliadas, atrav?s de um planejamento fatorial incompleto com tr?s fatores e tr?s n?veis (Box-Behnken) e da metodologia de superf?cie de resposta, as influ?ncias da press?o e temperatura do fluido supercr?tico e do tempo de pr?-tratamento (imers?o da planta em solu??o b?sica) no teor do alcal?ide licopodina no extrato. O extrato era purificado pelo processo ?cido-base de Stas-Otto e ent?o analisado por cromatografia gasosa acoplada ? espectrometria de massas, sendo o teor de licopodina definido pela normaliza??o das ?reas dos picos do cromatograma. A press?o foi avaliada entre 200 e 300 bar, a temperatura entre 40 a 60?C e o tempo de imers?o foi de zero a duas horas. Apenas press?o e temperatura foram estatisticamente significativas, sendo ent?o par?metros ideais para a extra??o: 300 bar, 40?C, sem a imers?o da planta na solu??o alcalina. Nessas condi??es, obteve-se um teor de 20,29% de licopodina no extrato final e foi levantada a curva de rendimento da extra??o em fun??o tempo. A curva foi modelada matematicamente, com bom ajuste, pelos modelos de Crank (1975), Sovov? (1994) e Reverchon (1996). Assim, foram estimados par?metros relacionados ? transfer?ncia de massa, importantes para simula??o e scale-up do processo, tais como o coeficiente de difus?o e coeficientes de transfer?ncia de massa. Nesse estudo, a extra??o com CO2 supercr?tico mostrou-se tecnicamente vi?vel para a obten??o de licopodina, sendo mais seletiva em rela??o ao processo de extra??o com etanol.
2

Produ??o de ?cido 3-indolac?tico, potencial rizog?nico e indu??o de respostas de defesa por Streptomyces SP. em plantas de eucalipto para o controle de botrytis cinerea

Salla, Tamiris Daros 22 August 2014 (has links)
Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2015-05-15T12:04:15Z No. of bitstreams: 1 468567 - Texto Completo.pdf: 3711593 bytes, checksum: 32dee061e07f3464cbf1a35564001f4c (MD5) / Made available in DSpace on 2015-05-15T12:04:15Z (GMT). No. of bitstreams: 1 468567 - Texto Completo.pdf: 3711593 bytes, checksum: 32dee061e07f3464cbf1a35564001f4c (MD5) Previous issue date: 2014-08-22 / Eucalyptus is an economically important woody species, especially as a raw material in many industrial sectors. Brazil ranks the second worldwide position in acreage, totalizing approximately three million hectares. Eucalyptus species are very susceptible to pathogens such as Botrytis cinerea (gray mold), which leads to mortality of cuttings in rooting phase. Biological control of plant diseases using soil microorganisms has been considered an alternative to reduce the use of pesticides and pathogen attack. Plant growth promoting rhizobacteria can act directly on plant development for production of phytohormones or indirectly as antagonists to pathogens, as well as promote changes in secondary metabolism, and hence inducing of systemic resistance. In this study, the direct roleof Streptomyces isolates in plant development was evaluated through the production of auxin and rhizogenic potential in Eucalyptus grandis and E. globulus plants, as well as indirectly, by modulation of the secondary metabolism, and induction of sistemic resistence in plantselicited with Streptomyces sp. and challenged with the pathogenic fungus B. cinerea. Metabolic responses were evaluated throughactivity of plant defense enzymes (PPO and POX) and induced secondary compounds (total phenolics and quercetinic-flavonoids fraction). The incidence and progression of gray mold disease on plants elicited Streptomyces sp. PM9, and coculture of these microorganisms (Streptomyces and B. cinerea) were also evaluated. Streptomyces sp. PM5 and PM9 isolates produced more auxin than the other isolates tested. Streptomyces sp. PM9 showed the highest rhizogenic potential on Eucalyptus sp. and modulated secondary metabolism of these plants. Antagonism of this isolated over B. cinerea was evidenced. Plants elicited with Streptomyces sp. PM9 and challenged with B. cinerea showed changes in PPO and POX enzymes and levels of phenolic compounds at different time points of analysis, which may be related to initial defense response. Phenolic compounds chlorogenic acid and gallic acid were, on average, the most abundant, while caffeic acid, benzoic acidand catechin were induced at specific time points. A delay in the onset of disease was significant in plants of E. grandis elicited with Streptomyces. The induction of resistance, disease delay and antagonism against B. cinereaindicate the capacity of Streptomyces sp. PM9 as an inducer of plant systemic resistance, and poses this microorganism as a potential candidate for biological control programs in nurseries of Eucalyptus. Interaction of rhizobacteria with eucalyptus plant, as well as the modulation of defense mechanisms may contribute to the establishment of new biocontrol strategies applied to forestry. / O eucalipto ? uma esp?cie lenhosa economicamente importante, destacando-se como mat?riaprima em diversos setores industriais. O Brasil ocupa a segunda posi??o mundial em ?rea plantada, totalizando aproximadamente tr?s milh?es de hectares. As esp?cies de eucalipto s?o muito suscet?veis a pat?genos como Botrytis cinerea (mofo-cinzento), o qual leva ? mortalidade de estacas em fase de enraizamento. O controle biol?gico de doen?as em plantas utilizando microrganismos do solo tem sido considerado uma alternativa para reduzir o uso de agroqu?micos e o ataque de pat?genos. Rizobact?rias promotoras de crescimento vegetal podem agir diretamente no desenvolvimento das plantaspela produ??o de fitorm?niosou indiretamente, como antagonistas a fungos patog?nicos, al?m de causar altera??es no metabolismo secund?rio, com consequente indu??o de resist?ncia sist?mica. Neste trabalho, avaliou-se a a??o direta no desenvolvimento vegetal de isolados rizobacterianos do g?nero Streptomyces atrav?s da produ??o de auxinas e potencial rizog?nico de Eucalyptus grandis e E. globulus, bem como oefeito modulador no metabolismo secund?rioe a indu??o de resist?ncia sist?mica em plantas eliciadas com Streptomyces sp. e desafiadas com o fungo patog?nico B. cinerea. As respostas metab?licas foram avaliadas atrav?s das atividades de enzimas realacionadas ? defesa vegetal (PPO e POX) e dos compostos secund?rios induzidos (compostos fen?licos totais e fra??o flavon?ides quercet?nicos). A incid?ncia e progress?o da doen?a mofo cinzento em plantas eliciadas com Streptomyces sp. PM9, e cocultivo destes microrganismos (Streptomyces e B.cinerea) tamb?m foram avaliados. Os isolados de Streptomycessp.PM5 e PM9 apresentaram maior produ??o de auxina que os demais isolados testados. Streptomyces sp.PM9 apresentou o maior potencial rizog?nico em plantas de Eucalyptus sp. emodulou o metabolismo secund?rio destas plantas. Oantagonismo deste isolado sobre B. cinerea foi evidenciado.As plantas eliciadas com Streptomyces sp. PM9 e desafiadas com B. cinereaapresentaram altera??es nas enzimas PPO e POXe nos n?veis de compostos fen?licos totais em diferentes tempos de an?lise, as quais foram relacionadas ? resposta inicial de defesa.Os compostos fen?licos ?cido g?lico e clorog?nico foram, em m?dia, os mais abundantes, embora os ?cidos cafeico e benzoico e a catequina tenham sido induzidos em momentos espec?ficos. O retardo no estabelecimento da doen?a foi significativo em plantas de E. grandis eliciadas com Streptomyces. Os resultados de indu??o de resist?ncia, retardo da doen?a eantagonismocontra B.cinerea, demonstram a capacidade de a??o de Streptomycessp. PM9 como indutor de resist?ncia sist?mica vegetal, colocando este microrganismo como potencial candidato aos programas de controle biol?gico em viveiros de mudas de Eucalyptus. A intera??o da planta de eucalipto com a rizobact?ria, bem como a modula??o dos mecanismos de defesa podem contribuir para o estabelecimento de novas estrat?giasde biocontrole aplicado ? silvicultura.

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