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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

Obten??o do extrato vol?til de sementes de Anethum graveolens L. por diferentes t?cnicas extrativas / Obtaining volatile extract of Anethum graveolens L. by different extractive techniques

Garcez, Jos? Jacques 03 August 2016 (has links)
Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2016-09-26T11:17:54Z No. of bitstreams: 1 DIS_JOSE_JACQUES_GARCEZ_COMPLETO.pdf: 2188213 bytes, checksum: 52d9379f9b56a2cbd55ff55765b34197 (MD5) / Made available in DSpace on 2016-09-26T11:17:54Z (GMT). No. of bitstreams: 1 DIS_JOSE_JACQUES_GARCEZ_COMPLETO.pdf: 2188213 bytes, checksum: 52d9379f9b56a2cbd55ff55765b34197 (MD5) Previous issue date: 2016-08-03 / This master thesis aimed the study of different extraction techniques and the influence of different particle sizes in maximizing the yield of essential oil from the seeds of dill, an herb widely used in cooking and in traditional folk medicine and has a wide range of properties conferred such as antimicrobial, antibacterial and antioxidant. The techniques used for obtaining the essential oil were extracted by steam distillation and hydrodistillation, where different average particle sizes of crushed seed and anise were considered, and extraction with supercritical carbon dioxide, where besides the variation of average particle sizes it was used different pressure values. For the supercritical extraction, it was then used the response surface method in which the variables pressure and average particle diameter were investigated, also a 2? factorial design was used to determine the number of experiments required. The best conditions for the three extractive methods were found, being larger diameters of particles to steam distillation and hydrodistillation, and 10,000 kPa and smaller diameter particles to the supercritical extraction. In this evaluation, it was performed mathematical modeling of the yield versus time curves of the best extraction conditions for each of the techniques. The extracts were analyzed in a gas chromatograph coupled to a mass spectrometer, after, the results have undergone a statistical analysis of major components, which were divided into 3 different groups according to their similar compositions. Finally, its antibacterial activities were tested where all extracts showed activity against E. coli. / Este trabalho tem como objetivo o estudo sobre algumas diferentes t?cnicas de extra??o e a influ?ncia de diferentes granulometrias na maximiza??o do rendimento do ?leo essencial das sementes do endro, uma erva utilizada na culin?ria e na medicina popular tradicional e que possui uma ampla gama de propriedades atribu?das tais como atividade antibacteriana, antif?ngica e antioxidante. As t?cnicas realizadas para a obten??o do ?leo essencial foram: extra??o por arraste a vapor e hidrodestila??o, onde diferentes tamanhos m?dios das part?culas de sementes mo?das do endro foram considerados, e extra??o com di?xido de carbono supercr?tico, onde al?m da varia??o dos tamanhos m?dios das part?culas, foram empregados diferentes valores de press?es. Para a extra??o supercr?tica, foi ent?o utilizado o m?todo de superf?cie de respostas onde as vari?veis, press?o e di?metro m?dio de part?culas foram investigados, tamb?m, um planejamento fatorial 2? foi aplicado para determinar a quantidade de experimentos necess?rios. As melhores condi??es nos tr?s m?todos extrativos foram encontradas, sendo maiores di?metros de part?culas para o arraste a vapor e a hidrodestila??o e 10.000 kPa e menor di?metro de part?culas para a extra??o supercr?tica. Al?m desta avalia??o, foram realizadas modelagens matem?ticas das curvas de rendimento versus tempo das melhores condi??es de extra??o referente a cada uma das t?cnicas. Os extratos foram analisados em um cromat?grafo a g?s acoplado a um espectr?metro de massas, ap?s, os resultados passaram por uma an?lise estat?stica de componentes principais, onde foram divididos em tr?s diferentes grupos de acordo com suas semelhantes composi??es. Por fim, suas a??es antibacterianas foram testadas onde todos os extratos apresentaram atividade frente a E. coli.
2

Estudo da atividade antimicrobiana de ?leos essenciais extra?dos por destila??o por arraste a vapor e por extra??o supercr?tica

Pereira, Marcos Aur?lio Almeida 23 March 2010 (has links)
Made available in DSpace on 2015-04-14T13:58:37Z (GMT). No. of bitstreams: 1 424078.pdf: 9953228 bytes, checksum: 4e0909682fa6bd6bc56846badd6c3dde (MD5) Previous issue date: 2010-03-23 / A utiliza??o de ?leos essenciais na pesquisa sobre a atividade antimicrobiana ? bastante intensa e tem aumentado a cada ano. Por?m, a influ?ncia do processo de extra??o na composi??o qu?mica dos ?leos essenciais e o impacto da intera??o de seus compostos na atividade antimicrobiana t?m sido menos estudados. Os ?leos essenciais de Rosmarinus officinalis L. e Cymbopogum winterianus Jowitt foram extra?dos por arraste a vapor e por extra??o supercr?tica. O processo de extra??o influenciou diretamente na composi??o qu?mica dos ?leos e conseq?entemente na atividade antimicrobiana. O ?leo de Cymbopogum citratus DC. Stapf. foi extra?do por arraste a vapor e durante a avalia??o da atividade antimicrobiana, o composto citral apresentou uma forte atividade. A atividade antimicrobiana dos ?leos estudados foi avaliada pelo m?todo de bioautografia indireta que permite a separa??o da composi??o qu?mica dos ?leos em fra??es, as quais foram analisadas por cromatografia gasosa acoplada a um espectr?metro de massa (GC-MS). A concentra??o inibit?ria m?nima dos ?leos Cymbopogum citratus DC. Stapf. e Cymbopogum winterianus Jowitt, os quais foram ativos contra os microorganismos citados na Portaria 15 da ANVISA de 1988, foi determinada pelo m?todo de dilui??o em tubos. Al?m disto, as dilui??es em tubos foram plaqueadas, por al?a calibrada, a fim de se verificar seu efeito bacteriost?tico ou bactericida.
3

Incorpora??o de modelos termodin?micos na modelagem matem?tica de processos de extra??o supercr?tica

Silva, Rodrigo Scopel 29 January 2013 (has links)
Made available in DSpace on 2015-04-14T13:58:57Z (GMT). No. of bitstreams: 1 446078.pdf: 1260419 bytes, checksum: 2a65fd467463de0a017aea78cdea045d (MD5) Previous issue date: 2013-01-29 / Clove (Syzygium aromaticum) essential oil is widely cultivated on eastern countries and has antifungal, antibacterial, insecticidal, and antioxidant properties. Given its vegetal structure, Clove essential oil can be extracted by supercritical fluid. The aim of this work is to model the solubility and the mass transfer process of clove essential oil in supercritical carbon dioxide. For the thermodynamic modeling, the Peng Robinson equation of state was coupled with four mixing rules: van der Waals 1 (vdW1), van der Waals 2 (vdW2), Mathias-Klotz-Prausnitz (MKP) and LCVM. Isothermal vapor-liquid equilibria calculation of CO2/clove essential oil were conducted as a binary system and CO2/eugenol/β-caryophyllene as a ternary system, where the oil composition is defined from major oil compounds, i.e., eugenol and β caryophyllene. A Matlab mathematical procedure was developed to obtain the adjustable parameters of the mixing rules for both the binary and ternary mixture at the following temperatures: 313.2 K, 318.2 K and 328.2 K. Results show that the mixing rule that best fit the experimental data for the binary system CO2/clove oil is vdw2 with a %ΔP of 3.07%. For the ternary mixture, the mixing rule that best represent the experimental data is MKP with a %ΔP of 2.18%. The coupling among solubility calculation and mass transfer model described quantitatively very well the extraction experimental data. The coefficient of determination (R2) showed the minimum value of 0.9946 for conditions investigated. / ?leo essencial de cravo da ?ndia (Syzygium aromaticum), amplamente cultivado nos pa?ses do leste, apresenta propriedades antibacteriana, anti-f?ngica, inseticida e antioxidante. Devido ?s caracter?sticas da estrutura vegetal do cravo da ?ndia seu ?leo essencial pode ser obtido atrav?s da extra??o por fluido supercr?tico. O objetivo deste trabalho ? modelar a solubilidade do ?leo essencial de cravo em di?xido de carbono supercr?tico e o processo de transfer?ncia de massa de sua extra??o. Para a modelagem termodin?mica, a equa??o de estado de Peng Robinson foi acoplada com quatro regras de mistura: van der Waals 1 (vdW1), van der Waals 2 (vdW2), Mathias-Klotz-Prausnitz (MKP) e LCVM. Foram realizados c?lculos isot?rmicos do equil?brio l?quido-vapor de CO2/?leo essencial de cravo, considerado como um sistema bin?rio e CO2/eugenol/β-cariofileno como um sistema tern?rio, onde a composi??o do ?leo ? definida a partir dos seus compostos majorit?rios, isto ?, eugenol e β-cariofileno. Foi desenvolvida uma rotina matem?tica no software Matlab para obter os par?metros ajust?veis das regras de mistura, tanto para a mistura bin?ria quanto para a mistura tern?ria, nas seguintes temperaturas: 313,2 K, 318,2 K, 328,2 K. Os resultados mostraram que a regra de mistura que melhor ajustou os dados experimentais para o sistema bin?rio CO2/?leo essencial de cravo foi vdW2, com um %ΔP de 3,07%. Para a mistura tern?ria, a regra de mistura que melhor representou os dados experimentais foi MKP com %ΔP igual a 2,18%. Ao acoplar os dados de solubilidade calculados ao modelo de transfer?ncia de massa, observou-se uma grande capacidade de representa??o dos dados experimentais de extra??o. O coeficiente de determina??o (R2) apresentou o valor m?nimo de 0,9946 para as condi??es investigadas.
4

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.
5

Uso da extra??o supercritica na obten??o de produtos com valor agregado a partir de res?duos s?lidos da ind?stria vin?cola

Rosa, Ant?nio Alberto Andrade da 29 August 2014 (has links)
Made available in DSpace on 2015-04-14T13:59:12Z (GMT). No. of bitstreams: 1 463988.pdf: 1527906 bytes, checksum: 9a3c3ab5218bb7340aa6e1c30278870c (MD5) Previous issue date: 2014-08-29 / The study of the extraction of substances with value-added from waste of the wine industry is proposed due to the annual generating thousands of tons of seeds and cables, called bagasse, coming wineries of the productive region of the northeastern state of Rio Grande do Sul processes. At this moment, this material is perceived as process residue and used only as raw material for composting. Studies show that grape seed (Vitis vinifera L.) may contain compounds with high antioxidant power. The antioxidant power of the extract gives it desirable characteristics for applications in human health, and can be used as food, medicine and cosmetic formulation. In this work the grape waste were collected 20 to 30 days post-pressing and separated into two fractions: one composed only by grape seeds and the other by the remaining material (pulp, peel and bits of curl). Both fractions were subjected to supercritical extraction process using carbon + water and carbon dioxide as solvents. Process operating conditions were: temperature 35 ? C and pressures of 100, 120, 150, 200 and 250 bar, yielding data for construction of yield versus time curves. Then the mathematical modeling was applied to represent the extraction process, this study grounded on the knowledge of mass transfer. Regarding the extracts, they were assessed using DPPH (2,2-diphenyl-1-picryl-hydrazyl), aimed to determining the antioxidant power. As a result, it was observed that the extracts of the pulp, and pieces of bark curl had a high antioxidant power and the mathematical model employed showed high adherence to the experimental data represented by the extraction curve. / O estudo da extra??o de subst?ncias com valor agregado dos res?duos da ind?stria vin?cola ? proposto devido ? gera??o anual de milhares de toneladas de sementes e cabos, chamados de baga?o, oriundos dos processos produtivos das vin?colas da regi?o nordeste do estado do Rio Grande do Sul. At? o presente momento este material ? percebido como res?duo de processo e utilizado somente como mat?ria-prima para compostagem. Estudos demonstram que as sementes de uva (Vitis vin?fera L.) podem conter compostos com elevado poder antioxidante. O poder antioxidante do extrato confere a ele caracter?sticas desej?veis para aplica??es em benef?cio da sa?de humana, podendo ser utilizado como alimento, medica??o e na formula??o de cosm?ticos. Neste trabalho os res?duos de uva foram coletados 20 a 30 dias p?s-prensagem e separado em duas fra??es: uma constitu?da s? por sementes de uva e a outra pelo material restante (polpa, casca e peda?os de cacho). As duas fra??es foram submetidas ao processo de extra??o supercr?tica, utilizando di?xido de carbono e di?xido de carbono + ?gua como solventes. As condi??es operacionais de processo foram as seguintes: temperatura de 35?C e press?es de 100, 120, 150 200 e 250 bar, gerando curvas de rendimento versus tempo. Aplicou-se ent?o a modelagem matem?tica ao processo de extra??o, estudo este embasado nos conhecimentos de transfer?ncia de massa. Em rela??o aos extratos, os mesmos foram analisados pela metodologia DPPH (2,2-difenil-1-picril-hidrazil), visando ? determina??o do poder antioxidante. Como resultado, observou-se que os extratos da polpa, casca e peda?os de cacho tiveram um elevado poder antioxidante e o modelo matem?tico empregado apresentou alta ader?ncia aos dados experimentais representados pela curva de extra??o.
6

Projeto de engenharia do processo de extra??o supercr?tica de cafe?na da erva mate / Process study of caffeine supercritical extraction from yerba mate

Petersen, Helena de Souza 27 March 2017 (has links)
Submitted by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-06-30T17:34:35Z No. of bitstreams: 1 DIS_HELENA_DE_SOUZA_PETERSEN_COMPLETO.pdf: 655908 bytes, checksum: 7c6cf0da861a822fa2beba34ea724e4b (MD5) / Made available in DSpace on 2017-06-30T17:34:35Z (GMT). No. of bitstreams: 1 DIS_HELENA_DE_SOUZA_PETERSEN_COMPLETO.pdf: 655908 bytes, checksum: 7c6cf0da861a822fa2beba34ea724e4b (MD5) Previous issue date: 2017-03-27 / The supercritical extraction emerged at the last decades as a green technology and as an alternative process to produce natural products and food. The process of supercritical extraction, using CO2 as a solvent, has been extensively studied, but there are fewer works about scale-up. Therefore, this work proposes to study the industrial supercritical fluid extraction of caffeine from yerba mate to produce decaffeinated yerba mate, an innovative product in the market, and caffeine, a product that has equal or even more value in the market than the main product. Design basis of this work are the experimental results of supercritical extraction in pilot scale and the appliance of a scale-up method based on the maintenance of the solvent mass flow and the raw-material mass flow proportion. Thus, process data sheet of main equipment were generated: extraction vessel, heat exchanger and high pressure pump. The maximum daily caffeine extraction capacity was estimated at two tons and the solvent mass flow rate of 22 t/h was obtained from the equation residence time of the solvent, maintaining constant the porosity of the 0.79 bed obtained in scale pilot. In addition, a process flow diagram was proposed for an industrial scale plant supercritical extraction of caffeine from yerba mate. / A extra??o supercr?tica emergiu nas ?ltimas d?cadas como uma tecnologia verde promissora e uma alternativa para o processamento de alimentos e produtos naturais. O processo de extra??o supercr?tica, utilizando CO2 como solvente, vem sendo extensivamente estudado, mas poucos ainda s?o os trabalhos que visam o escalonamento do processo. Logo, este trabalho prop?e estudar o processo industrial de extra??o supercr?tica de cafe?na a partir da erva-mate, que tem como meta produzir erva-mate descafe?nada, produto inovador no mercado, e cafe?na, um subproduto t?o ou mais valorizado que o produto principal. A base de c?lculo s?o os experimentos realizados em escala piloto e a utiliza??o de m?todo de aumento de escala que prop?e a manuten??o de propor??o de massa de solvente e massa de mat?ria-prima. Sendo assim, foram geradas folhas de dados de processo para os principais equipamentos: vaso extrator, trocadores de calor e bomba de alta press?o. A capacidade di?ria m?xima de extra??o de cafe?na foi prevista em duas toneladas e a vaz?o m?ssica de solvente de 22 toneladas/hora foi obtida a partir do equacionamento de tempo de resid?ncia do solvente, mantendo constante a porosidade do leito de 0,79 obtida em escala piloto. Al?m disto, foi proposto um fluxograma para uma planta em escala industrial de extra??o supercr?tica da cafe?na a partir da erva mate.
7

Obten??o de extratos vol?teis e n?o vol?teis de Pluchea sagittalis (Lam.) Cabrera (Quitoco) : processos e an?lises / Obtaining volatile and non-volatile extracts of Pluclea sagittalis (quitoco) : processes and analyzes

Grandini, Camila Pereira 28 March 2017 (has links)
Submitted by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-06-30T17:35:25Z No. of bitstreams: 1 DIS_CAMILA_PEREIRA_GRANDINI_COMPLETO.pdf: 928123 bytes, checksum: 31401f36512c1229c7213472576341c1 (MD5) / Made available in DSpace on 2017-06-30T17:35:25Z (GMT). No. of bitstreams: 1 DIS_CAMILA_PEREIRA_GRANDINI_COMPLETO.pdf: 928123 bytes, checksum: 31401f36512c1229c7213472576341c1 (MD5) Previous issue date: 2017-03-28 / Conselho Nacional de Pesquisa e Desenvolvimento Cient?fico e Tecnol?gico - CNPq / The growing concern of industries in finding natural inputs in place of synthetic ones in the production of bioactive products in the pharmaceutical, food and cosmetic areas motivated this research to the study of the biological activities of the volatile and non-volatile extracts of Pluchea sagittalis. This plant known as quitoco of spontaneous growth in nature is found in tropical regions having its origin in the South American continent. The goal of this study was to obtain volatile and nonvolatile extracts from the aerial parts of the quitoco and to evaluate the chemical composition and the biological activities of the extracts obtained. In order to obtain extracts from leaf and stem samples of P. sagittalis, without flowers and flower samples, two processes were used: Extraction by steam drag, to obtain volatile extracts, and supercritical extraction, to obtain non-volatile extracts. The chemical composition of the extracts obtained by steam drag was analyzed by gas chromatography coupled with mass spectrometer. The antimicrobial activity of leaf and stem essential oil was tested with the bacteria Staphylococcus aureus and Escherichia coli and also with the fungus Candida albicans, both tests were performed using the indirect bioautography technique where the oil showed growth inhibition for Staphylococcus aureus and for the fungus Candida albicans. Volatile extracts of leaves and stems and flowers obtained by steam extraction and supercritical fluid at 90 bar pressure were evaluated for their aromatic potential by means of sensorial (olfatometric) analysis, having as best evaluation the extract obtained by supercritical extraction of quitoco flowers. / A crescente preocupa??o de ind?strias em encontrarem insumos naturais em substitui??o aos sint?ticos na produ??o de produtos bioativos nas ?reas farmac?utica, aliment?cia e cosm?tica motivou esta pesquisa quanto ao estudo das atividades biol?gicas dos extratos vol?teis e n?o vol?teis da Pluchea sagittalis. Esta planta conhecida como quitoco, de crescimento espont?neo, ? encontrada em regi?es tropicais tendo sua origem no continente sul-americano. O objetivo deste estudo consistiu em obter extratos vol?teis e n?o vol?teis das partes a?reas do quitoco e avaliar a composi??o qu?mica e as atividades biol?gicas dos extratos obtidos. Para a obten??o dos extratos a partir de amostras das folhas e talos da P. sagittalis, sem as flores, e amostras de flores foram utilizados dois processos: extra??o por arraste a vapor, para a obten??o de extratos vol?teis, e extra??o supercr?tica, para a obten??o de extratos vol?teis e n?o vol?teis. A composi??o qu?mica dos extratos obtidos por arraste a vapor foi determinada atrav?s da an?lise por cromatografia gasosa acoplada com espectr?metro de massa. A atividade antimicrobiana do ?leo essencial das folhas e talos foi testada com as bact?rias Staphylococcus aureus e Escherichia coli e tamb?m com o fungo Candida albicans, ambos os testes foram realizados atrav?s da t?cnica bioautografia indireta, onde o ?leo essencial apresentou inibi??o do crescimento para Staphylococcus aureus e para o fungo Candida albicans. Os extratos vol?teis das folhas e talos e das flores, obtidos atrav?s da extra??o por arraste a vapor e com fluido supercr?tico a 90 bar de press?o, foram avaliados quanto ao seu potencial arom?tico por meio de an?lise sensorial (olfatom?trica), tendo o extrato vol?til das flores obtido por extra??o supercr?tica um grande potencial para o uso em perfumaria.
8

Extra??o de cromenos a partir de Ageratum conyzoides L. : identifica??o qu?mica e modelagem matem?tica do processo

Almeida, Patr?cia Carvalho 30 November 2015 (has links)
Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2016-03-28T11:33:08Z No. of bitstreams: 1 DIS_PATRICIA_CARVALHO_ALMEIDA_COMPLETO.pdf: 1695882 bytes, checksum: 485e636dfb13c1dacc99571a2309aa50 (MD5) / Made available in DSpace on 2016-03-28T11:33:08Z (GMT). No. of bitstreams: 1 DIS_PATRICIA_CARVALHO_ALMEIDA_COMPLETO.pdf: 1695882 bytes, checksum: 485e636dfb13c1dacc99571a2309aa50 (MD5) Previous issue date: 2015-11-30 / Extracts obtained from natural products have attracted the interest of pharmacological sector due to the chemical and biological properties. Therefore, in this work were studied the chromenes (precocene I and II) extraction processes, steam distillation and supercritical fluid extraction (SFE), from Ageratum conyzoides L. Essential oil was extracted by saturated steam at 1.0, 1.5, and 2.0 bar and the supercritical fluid extractions were performed at 40?C and 90, 120, 150, and 200 bar to obtain non-volatile extracts. The essential oils were analyzed by gas chromatography/mass spectroscopy while the non-volatile extracts composition was determined by high-performance liquid chromatography. The essential oil presented two major compounds, precocene I (28.24 ? 2.64%) and precocene II (28.55 ? 2.08%). At 90 bar, the SFE resulted in higher yield and selectivity for precocene I and II, which represent 65.06% of extract. It was observed that the yield of chromenes varies according to pressure of SFE, however this behavior was not observed in the extracts obtained by steam distillation. A mathematical model was also used to simulate the processes and a good correlation was attained with the experimental data. / Extratos obtidos a partir de produtos naturais t?m atra?do o interesse do setor farmacol?gico devido ?s propriedades qu?micas e biol?gicas. Portanto, neste trabalho foram estudados os processos de extra??o de cromenos (precoceno I e II), destila??o a vapor e extra??o com fluido supercr?tico (SFE), a partir de Ageratum conyzoides L. O ?leo essencial foi extra?do por vapor saturado a 1,0, 1,5, e 2,0 bar e as extra??es com fluido supercr?tico foram realizadas a 40?C e 90, 120, 150, e 200 bar para obter extratos n?o vol?teis. Os ?leos essenciais foram analisados por cromatografia gasosa e espectroscopia de massa, enquanto que a composi??o dos n?o-vol?teis extratos foi determinada por cromatografia l?quida de alta efici?ncia. O ?leo essencial apresentou dois compostos principais, precoceno I (28,24 ? 2,64%) e precoceno II (28,55 ? 2,08%). A 90 bar, a SFE resultou em maior rendimento e seletividade para os precoceno I e II, que representaram 65,06% do extrato. Observou-se que o rendimento de cromenos varia de acordo com a press?o da SFE, no entanto, isto n?o foi observado nos extratos obtidos por meio de destila??o a vapor. Um modelo matem?tico tamb?m foi usado para simular os processos e uma boa correla??o foi obtida com os dados experimentais.
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Estudo de extra??o de C. roseus e produ??o de nanopart?culas para libera??o de vimblastina / Study of C. roseus extraction and production of nanoparticles for vinblastine release

Falc?o, Manuel Alves 30 March 2016 (has links)
Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2016-09-12T16:18:06Z No. of bitstreams: 1 TES_MANUEL_ALVES_FALCAO_COMPLETO.pdf: 3543313 bytes, checksum: c6209bccf7d4cd318c874850a1bc853d (MD5) / Made available in DSpace on 2016-09-12T16:18:06Z (GMT). No. of bitstreams: 1 TES_MANUEL_ALVES_FALCAO_COMPLETO.pdf: 3543313 bytes, checksum: c6209bccf7d4cd318c874850a1bc853d (MD5) Previous issue date: 2016-03-30 / Chemotherapy is highlighted for the treatment of many classes of tumors, especially by new drug delivery nanosystems. The drug delivery nanosystems are focused on greater selectivity for abnormal tissue, decrease adverse effects, dose reduction and decreased frequency applications. Due to the scale of these systems, the EPR effect favors the permeabilization in blood vessels and retention in tumor tissue particles. This thesis performed vinblastine extractions from C. roseus using water and ethanol as co-solvents for CO2 at 300 bar and at different temperatures, those experiments showed the viability of this extraction method, subsequent extractions were optimized using ethanol. The results are compared to traditional extraction methods such as solid-liquid extraction the results found was up to 92.41%. Concluding that vinblastine extraction using carbon dioxide and ethanol mixtures at high pressure is possible. The PLGA nanoparticles containing vinblastine showed again the reproducibility of the nanoemulsion method of ensuring the production of homogeneous nanoparticles with and without drug and cell viability experiments show that the three formulations of PLGA nanoparticles containing vinblastine potentiated drug activity at the lower doses, 1 and 5 ?g/mL, compared to free drug. The studies of glycopolymers synthesis presented the novel synthesis of an ATRP initiator based on PLGA without using PEG spacers. This initiator may, in future studies, be used for modifying PLGA. Successive attempts monomer polymerization saccharide via ATRP in water and DMSO leads to the conclusion that this approach is not the most suitable for the syntheses of glycopolymers graft from a PLGA initiator without the use of PEG spacers. / A quimioterapia ? op??o terap?utica para o tratamento de diversas classes de tumores, principalmente pelos novos nanosistemas de libera??o modificada de f?rmacos. Os nanosistemas de libera??o modificada t?m como foco a maior seletividade aos tecidos anormais, a diminui??o de efeitos adversos, redu??o da dose e diminui??o da frequ?ncia de aplica??es. Devido a escala destes sistemas, o efeito EPR favorece a permeabiliza??o nos vasos sangu?neos e a reten??o de part?culas no tecido tumoral. Nesta tese foram realizadas extra??es de vimblastina a partir de C. roseus utilizando ?gua e etanol como cossolventes de CO2 a 300 bar e a diferentes temperaturas mostraram a viabilidade do m?todo de extra??o, posteriormente, as extra??es foram otimizadas utilizando etanol. Quando os resultados encontrados s?o comparados a m?todos tradicionais de extra??o como a extra??o s?lido-l?quido o resultado encontrado foi de at? 92,41% superior. Concluindo, que a extra??o de vimblastina utilizando misturas de di?xido de carbono e etanol a altas press?es ? poss?vel. As nanopart?culas de PLGA contendo vimblastina demonstraram a reprodutibilidade do m?todo de nanoemuls?o garantindo a produ??o de nanopart?culas homog?neas, com e sem f?rmaco. Os experimentos de viabilidade celular mostraram que as tr?s formula??es de nanopart?culas de PLGA contendo vimblastina potencializaram a atividade do f?rmaco para as doses mais baixas, 1 e 5 ?g/mL, em rela??o ao f?rmaco livre. Os estudos realizados de s?ntese de glicopol?meros apresentaram a s?ntese in?dita de um iniciador de ATRP baseado em PLGA sem o uso de espa?adores de PEG. Este iniciador pode, em futuros estudos, ser utilizado para a modifica??o de PLGA. As sucessivas tentativas de polimeriza??o de mon?meros de sacar?deos via ATRP em ?gua e DMSO leva a conclus?o que esta metodologia n?o ? a mais adequada para s?nteses glicopol?meros conjugados a PLGA sem o uso de espa?adores de PEG.
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Extra??o, caracteriza??o e avalia??o bioativa do extrato de Arrabidaea chica

Santos, Rog?rio Pitanga 15 June 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-03-31T23:01:40Z No. of bitstreams: 1 RogerioPitangaSantos_DISSERT.pdf: 4092044 bytes, checksum: 81e41394327b3f461988b98662aa355f (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-04-04T22:17:21Z (GMT) No. of bitstreams: 1 RogerioPitangaSantos_DISSERT.pdf: 4092044 bytes, checksum: 81e41394327b3f461988b98662aa355f (MD5) / Made available in DSpace on 2016-04-04T22:17:21Z (GMT). No. of bitstreams: 1 RogerioPitangaSantos_DISSERT.pdf: 4092044 bytes, checksum: 81e41394327b3f461988b98662aa355f (MD5) Previous issue date: 2015-06-15 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / A utiliza??o de plantas com finalidades medicinais ? milenar, sendo bastante difundida sua aplica??o em medicamentos. Apesar das plantas serem fontes promissoras para a descoberta de novas mol?culas de interesse farmacol?gico, estimativas revelam que apenas 17% delas foram estudadas quanto a sua possibilidade de uso na medicina. Assim, a biodiversidade da flora brasileira representa um imenso potencial de utiliza??o econ?mica pela ind?stria farmac?utica. A planta Arrabidaea chica, popularmente conhecida como ?pariri?, ? comum na regi?o Amaz?nica, e a ela s?o atribu?das v?rias propriedades medicinais. As folhas desta planta s?o ricas em antocianinas, que s?o compostos fen?licos com alto poder antioxidante. Os compostos antioxidantes desempenham um papel vital na preven??o de doen?as neurol?gicas e cardiovasculares, c?ncer e diabetes, entre outras. Dentre as antocianinas encontradas na Arrabidaea chica, destaca-se a Carajurina (6,7-dihidroxi-5,4?- dimetoxi-flavilium), que ? o principal pigmento encontrado nesta planta. O presente trabalho teve como objetivo geral o estudo sobre a extra??o supercr?tica e a extra??o convencional (s?lido-l?quido) de folhas da Arrabidaea chica, avaliando-se o rendimento dos processos extrativos, a atividade antioxidante e a quantifica??o de Carajurina contida nos extratos. As extra??es supercr?ticas utilizaram CO2 como solvente, adicionado de co-solvente (mistura etanol/?gua), e foram conduzidas pelo m?todo din?mico em um extrator de leito fixo. Os ensaios obedeceram a um planejamento fatorial fracion?rio 24-1, tendo como vari?veis resposta o rendimento do processo, o poder antioxidante e a concentra??o de Carajurina, e como vari?veis independentes a press?o, a temperatura, a concentra??o de co-solvente (v/v) e a concentra??o de ?gua no co-solvente (v/v). Os rendimentos (massa de extrato seco/massa de mat?ria-prima utilizada) obtidos da extra??o supercr?tica variaram de 15,1% a 32%, sendo que o melhor resultado foi obtido a 250 bar e 40?C, com uso do co-solvente a 30% (v/v) e concentra??o de ?gua no co-solvente igual a 50% (v/v). Atrav?s de an?lise estat?stica, verificou-se que a concentra??o de co-solvente apresentou efeito significativo sobre o rendimento. Os resultados de rendimento em massa para as extra??es convencionais foram de 8,1% (?gua) e 5,5% (etanol). Atrav?s de an?lises cromatogr?ficas em CLAE (Cromatografia L?quida de Alta Efici?ncia), a Carajurina foi quantificada em todos os extratos obtidos e os valores de concentra??o (massa de Carajurina/massa de extrato seco) variaram entre 1% e 2,21% para os extratos supercr?ticos. Quanto ?s extra??es convencionais, n?o foi detectada Carajurina no extrato aquoso, enquanto o extrato etan?lico apresentou teor de Carajurina igual a 7,04%, sendo, portanto, mais seletivo em Carajurina do que as extra??es supercr?ticas. A avalia??o do poder antioxidante (m?todo do sequestro do radical 2,2-difenil-1-picril-hidrazilDPPH) dos extratos supercr?ticos resultou em valores de EC50 (concentra??o efetiva que neutraliza 50% dos radicais livres) compreendidos entre 38,34 e 86,13 ?g/mL, enquanto que as extra??es convencionais resultaram em valores de EC50 de 167,34 (?gua) e 42,58 (etanol) ?g/mL. J? a quantifica??o dos compostos fen?licos (m?todo espectrofotom?trico de FolinCiocalteau) dos extratos supercr?ticos resultou em valores compreendidos entre 48,93 e 88,62 mg EAG/g extrato (EAG = Equivalentes de ?cido G?lico), enquanto que as extra??es s?lidol?quido resultaram em valores de 37,63 (?gua) e 80,54 (etanol) mg EAG/g extrato. A boa atividade antioxidante pode ser atribu?da n?o somente ? presen?a de Carajurina, mas tamb?m ? exist?ncia de outros compostos fen?licos e antioxidantes na Arrabidaea chica. Atrav?s da otimiza??o do planejamento experimental, foi poss?vel identificar o experimento que apresentou o melhor resultado considerando as quatro vari?veis resposta em conjunto. Este experimento foi realizado nas seguintes condi??es: press?o de 200 bar, temperatura de 40?C, concentra??o de co-solvente igual a 30% (v/v) e concentra??o de ?gua no co-solvente igual a 30% (v/v). Conclui-se que, dentro da faixa estudada, ? poss?vel obter o resultado ?timo utilizando condi??es operacionais mais amenas, o que implica em menores custos e maior facilidade de opera??o. / The use of plants for medicinal purposes is ancient, with widespread application in medicinal drugs. Although plants are promising sources for the discovery of new molecules of pharmacological interest, estimates show that only 17% of them have been studied for their possible use in medicine. Thus, biodiversity of Brazilian flora represents an immense potential for economic use by the pharmaceutical industry. The plant Arrabidaea chica, popularly known as ?pariri?, is common in the Amazon region, and it is assigned several medicinal properties. The leaves of this plant are rich in anthocyanins, which are phenolic compounds with high antioxidant power. Antioxidant compounds play a vital role in the prevention of neurological and cardiovascular diseases, cancer and diabetes, among others. Within the anthocyanins found in Arrabidaea chica, stands out Carajurin (6,7-dihydroxy-5,4?- dimethoxy-flavilium), which is the major pigment encountered in this plant. The present work aimed to study on supercritical extraction and conventional extraction (solid-liquid extraction) in leaves of Arrabidaea chica, evaluating the efficiency of the extractive processes, antioxidant activity and quantification of Carajurin contained in the extracts. Supercritical extraction used CO2 as solvent with addition of co-solvent (ethanol/water mixture) and were conducted by the dynamic method in a fixed bed extractor. The trials followed a 24-1 fractional factorial design, the dependent variables were: process yield, concentration of Carajurin and antioxidant activity; and independent variables were: pressure, temperature, concentration of co-solvent (v/v) and concentration of water in the co-solvent mixture (v/v). Yields (mass of dry extract/mass of raw material used) obtained from supercritical extraction ranged from 15.1% to 32%, and the best result was obtained at 250 bar and 40 ?C, co-solvent concentration equal to 30% and concentration of water in the co-solvent mixture equal to 50%. Through statistical analysis, it was found that the concentration of co-solvent revealed significant effect on the yield. Yields obtained from conventional extractions were of 8.1% (water) and 5.5% (ethanol). Through HPLC (High-performance liquid chromatography) analysis, Carajurin was quantified in all the extracts and concentration values (Carajurin mass/mass of dry extract) ranged between 1% and 2.21% for supercritical extraction. For conventional extraction, Carajurin was not detected in the aqueous extract, while the ethanol extract showed Carajurin content of 7.04%, and therefore, more selective in Carajurin than the supercritical extraction. Evaluation of antioxidant power (radical 2,2-diphenyl-1-picrylhydrazyl ? DPPH ? sequestration method) of the supercritical extracts resulted in EC50 values (effective concentration which neutralizes 50% of free radicals) ranged from 38.34 to 86.13 ?g/mL, while conventional extraction resulted in EC50 values of 167.34 (water) and 42.58 (ethanol) ?g/mL. As for the quantification of total phenolic content (Folin-Ciocalteau analysis) of the supercritical extracts resulted in values ranged from 48.93 and 88.62 mg GAE/g extract (GAE = Gallic Acid Equivalents), while solid-liquid extraction resulted in values of 37.63 (water) and 80.54 (ethanol) mg GAE/g extract. The good antioxidant activity cannot be attributed solely to the presence of Carajurin, but also the existence of other compounds and antioxidants in Arrabidaea chica. By optimizing the experimental design, it was possible to identify the experiment that presented the best result considering the four dependent variables together. This experiment was performed under the following conditions: pressure of 200 bar, temperature of 40 ?C, co-solvent concentration equal to 30% and concentration of water in the co-solvent mixture equal to 30%. It is concluded that, within the studied range, it is possible to purchase the optimum result using milder operating conditions, which implies lower costs and greater ease of operation.

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