Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2016-08-30T14:26:59Z No. of bitstreams: 1 2010 - Fernanda Peixoto Giori.pdf: 2362278 bytes, checksum: a15d423533272c981b15d7f22b714be1 (MD5) / Made available in DSpace on 2016-08-30T14:26:59Z (GMT). No. of bitstreams: 1 2010 - Fernanda Peixoto Giori.pdf: 2362278 bytes, checksum: a15d423533272c981b15d7f22b714be1 (MD5) Previous issue date: 2010-02-23 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior-CAPES / Brazil was adverted by the World Health Organization (WHO) as a sub-clinical area of serious vitamin A deficiency. Thus, the Brazilian Agricultural Research Corporation (EMBRAPA) is selecting and improving varieties of sweet potatoes with higher levels of Beta-carotene, pro-vitamin A. The carotenoids provitamin A amount of in foods does not necessarily correspond the amount that is absorbed and metabolized by the body. For a better determination of these values and knowledge of the mechanisms of its transport and absorption, it is necessary to understand the factors that lead to the food matrix release, until the absorption and the influence on the promotion and maintenance in human health. In order to perform preliminary studies of its absorption, this study aims to determine the efficiency of micellization of Beta -carotene in orange sweet potato (Ipomoea batatas, Lam), by applying a in vitro digestion as a tool for determining the bioaccessibility, which is the first step for bioavailability determination. This approach aims to simulate the oral, gastric and intestinal stages of human. The digestion was performed with 10 g of fresh samples, homozeneided with 5% (w/w) of canola oil. The extraction was performed with acetone and petroleum ether and the micellar fraction with petroleum ether, NaCl 10% (w / v) and NaSO4 2% (w/v) and involves the use of enzymes as -amylase , pepsin, bile, pancreatin, lipase and mucin, and inorganic compounds such as KCl, KSCN, NaH2PO4, Na3PO4, NaOH, NaCl, CaCl2, HCl, NaHCO3. The physiological variations are reproduced by the heating bath shaker with orbital gyrus (37?C) and centrifugation (5000g, 45 min). Quantification and determination of the profile of carotenoids were performed by high performance liquid chromatography (HPLC) with YCM ? C30 Carotenoid S-3 4.6 x 250mm column. Quantification of total carotenoids was performed by UV-VIs. The whole procedure was performed under controlled temperature (25 ? C) and light. The Beta -carotene was present mainly with levels of 86%, 73% and 82% for access 1, 2 and 3 and after digestion, the profile of Beta -carotene has set levels of 96%, 89% and 100%, respectively. The efficiency of micellization was 23.8%, 28% and 25% for 1.2 and 3 hits, indicating Beta -carotene transfer of the food matrix to micelles, corresponding to bioaccessibility of the compound. This methodology proved to be faster and cheaper, since the in vivo studies are costly, complex and require more time. / O Brasil foi classificado pela Organiza??o Mundial da Sa?de (OMS) como ?rea de car?ncia sub-cl?nica grave de vitamina A. Assim, a Empresa Brasileira de Pesquisa Agropecu?ria (EMBRAPA) v?m selecionando e melhorando variedades de batata-doce com teores maiores de Beta-caroteno, composto pr?-vitamina A. A quantidade de caroten?ides pr?-vitamina A presentes nos alimentos n?o corresponde necessariamente ?quela quantidade absorvida e metabolizada pelo organismo. Para uma melhor determina??o destes valores e conhecimento dos mecanismos de transporte e absor??o deste composto, faz-se necess?rio, o entendimento dos fatores que levam ? sua libera??o da matriz do alimento, at? a extens?o de sua absor??o, bem como a influ?ncia na promo??o e manuten??o da sa?de humana. A fim de realizar estudos preliminares de sua absor??o, este trabalho visa determinar a efici?ncia de miceliza??o de Beta-caroteno de batata-doce de polpa alaranjada (Ipomoea batatas, Lam.), atrav?s da aplica??o de digest?o in vitro, como ferramenta de determina??o da bioacessibilidade, etapa preliminar para a determina??o da biodisponibilidade. Esta metodologia visa simular as etapas de digest?o oral, g?strica e intestinal humana. Foram pesados 10g de amostra in natura e adicionados 5% (p/p) de ?leo de canola. A extra??o do alimento foi realizada com acetona e ?ter de petr?leo e a da fra??o micelar, com ?ter de petr?leo, NaCl 10%(p/v) e NaSO4 2%(p/v) . Enzimas como: a-amilase, pepsina, bile, pancreatina, lipase e mucina, bem como compostos inorg?nicos, tais como KCl, KSCN, NaH2PO4, Na3PO4, NaOH, NaCl, CaCl2, HCl, NaHCO3. As varia??es fisiol?gicas foram reproduzidas pelo banho de aquecimento com giro orbital (37?C) e centrifuga??o (5000g;45 min). A quantifica??o e determina??o do perfil de caroten?ides foi realizada por cromatografia l?quida de alta efici?ncia (CLAE), com coluna YCM? Carotenoid C30 S-3 de 4,6 x 250mm. A quantifica??o de caroten?ides totais foi realizada por espectrofotometria UV-VIs. Todo o procedimento foi executado sob temperatura (25?C) e luz controlada. O Beta-caroteno estava presente majoritariamente, com teores de 86%, 73% e 82%, para as variedades 1, 2 e 3 e ap?s a digest?o, o perfil do Beta-caroteno passou a configurar teores de 96%, 89% e 100%, respectivamente. A efici?ncia de miceliza??o foi de 23,8%, 28% e 28,9% para as variedades 1,2 e 3, indicando a transfer?ncia do - caroteno da matriz do alimento para as micelas, correspondendo a bioacessibilidade deste composto. Esta metodologia demonstrou-se mais r?pida e mais barata, quando comparada aos estudos in vivo, que s?o mais onerosos, complexos e demandam mais tempo.

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-09-05T20:11:17Z No. of bitstreams: 1 2016 - Fernanda Marques Peixoto.pdf: 14003225 bytes, checksum: 89c95a9ad22b1e74cdf2bda273665230 (MD5) / Made available in DSpace on 2017-09-05T20:11:17Z (GMT). No. of bitstreams: 1 2016 - Fernanda Marques Peixoto.pdf: 14003225 bytes, checksum: 89c95a9ad22b1e74cdf2bda273665230 (MD5) Previous issue date: 2016-12-08 / A lot of interest in the consumption of anthocyanins increased after the association of their intake and reduced risk of chronic diseases. Despite of in vitro evidences of anthocyanins benefits to health, there is still a gap in the knowledge of the mechanisms of absorption of anthocyanins by the human body. It is known that concentration of food anthocyanins doesn't reflect the amount of these compounds which are absorbed, metabolized, distributed and biologically active in humans. Some in vitro models have been developed to evaluate the steps of cell release and transport ( uptake) of these compounds from food. The objective of this study was to evaluate the in vitro absorption of food anthocyanins using the in vitro digestion followed by uptake and transport in Caco-2 human intestinal cell line and MKN-28 human gastric cell line. Initially, anthocyanins bioaccessibility of diverse fruits was evaluated in order to select the better sources for transport assays. The bioaccessibility assays were performed using an in vitro digestion model, which mimics the human oral, gastric and intestinal stages. Quantification and characterization of anthocyanins profile were performed by high-performance liquid chromatography (HPLC) with Thermo Scientific? C1s 2.4 (4.6 x 10mm) column. After selection of the most promising fruits, the bioaccessibility tests were followed by transport assays. To assess gastric absorption, the product from gastric digestion was applied on the MKN-28 cell monolayer, which was obtained after 7 days of culture of 2.5 x 10^5 MKN-28 cells seeded in RPMI culture media in transwell? plates. The permeate was collected after 30, 60, 120 andl80 minutes oftransport. For evaluation of intestinal absorption after digestion, the digesta from the intestinal phase was applied on the Caco-2 cell monolayer, which was obtained after 21 days of culture of 2.5 x 105 Caco-2 cells seeded in DMEM culture media in TRANSWELL? plates. The permeate was collected after 30, 60 and 120 minutes of transport. All analyses were made by forming CLUE / photodiode array detector (Thermo? Scientific) at 520nm. Peel powder from jabuticaba, jambo and Jamel?o were the most promising sources. The bioaccessibility of anthocyanins after gastric digestion was 13% for jabuticaba, 45 % for jambo and 65 % for jamel?o. In addition, the intestinal bioaccessibility was 1 O % for jabuticaba, 15 % for jambo and 45 % for jamel?o. The transport assay with the MKN-28 gastric cell line, revealed 19.7%, 9.7 % and 14.1 % of transport efficiency, respectively, for jambo, jabuticaba and jamel?o digestion products. While Caco-2 intestinal cell model showed 0.8 %, 0.2 % and 0.3 % oftransport efficiency, respectively, for jambo, jabuticaba and jamel?o. These results suggest food anthocyanins are preferentially absorbed by the human gastric mucosa and to a lesser extent by the human intestinal epithelium. / O interesse pelo consumo das antocianinas aumentou ap?s o surgimento da rela??o entre o seu consumo e a redu??o do risco de doen?as cr?nicas. Apesar das evid?ncias in vitro quanto a esses beneficios ? sa?de, ainda h? uma lacuna que permanece sob investiga??o: o mecanismo de absor??o das antocianinas pelo organismo humano. Sabe-se que a quantidade desses compostos, nos alimentos, n?o reflete a quantidade absorvida, metabolizada, distribu?da e biologicamente ativa em humanos. Alguns modelos in vitro t?m sido desenvolvidos para avaliar as etapas de digest?o e transporte celular (absor??o) de compostos dos alimentos. Assim, o objetivo deste trabalho foi avaliar o transporte in vitro de antocianinas em alimentos utilizando modelos de digest?o in vitro seguido do transporte em c?lulas intestinais Caco-2 e c?lulas g?stricas MKN-28. Na 1? etapa, oito frutos foram analisados quanto aos valores de bioacessibilidade (BCSS) fornecidos pelas antocianinas presentes, para posterior sele??o para os ensaios de transporte. Os ensaios de BCSS foram realizados com um modelo de digest?o in vitro, para simula??o das fases oral, g?strica e intestinal humana. A quantifica??o e determina??o do perfil de antocianinas foram realizadas por Cromatografia l?quida de alta efici?ncia (CLAE), com coluna Thermo? Scientific C1s 2,4 (4,6 x 100mm). Na 2? etapa, realizou-se os ensaios de BCSS, anteriormente aos ensaios de transporte, nos frutos potencialmente mais promissores. Para a avalia??o do transporte g?strico, na sequ?ncia, o digerido g?strico foi aplicado sobre a monocamada de c?lulas MKN-28, com 2,5 x 10^5 c?lulas, em meio RPMI, em placa transwell? e, ap?s 7 dias de cultivo, o permeado foi coletado nos tempos 30, 60, 120, 180 minutos. Para o transporte intestinal, sequencial, o digerido intestinal foi aplicado sobre a monocamada celular Caco-2, com 2,5 x 105 c?lulas, em meio DMEM, em placas transwell? e, ap?s 21 dias de cultivo, o permeado foi coletado nos tempos 30, 60 e 120 minutos de transporte. Todas as an?lises foram realizadas por CLUE/detector de arranjo fotodiodo (Thermo? Scientific), a 520 nm. Os p?s da casca da jabuticaba, jambo e jamel?o foram as matrizes mais promissoras. A BCSS das antocianinas, ap?s a digest?o g?strica, foi de 13 % parajabuticaba, 45 % parajambo e 65 % parajamel?o, enquanto a BCSS intestinal foi de 10% para jabuticaba, 15 % para jambo e 45 % para jamel?o. Os ensaios de transporte (ET) com os modelos de c?lula MKN-28 resultaram em 19,7; 9,7 e 14,1 % de ET, respectivamente, para os p?s do jambo, jabuticaba, e jamel?o, enquanto que o modelo Caco-2, resultaram em 0,8, 0,2 e 0,3 % de ET, respectivamente. Estes resultados sugerem que as antocianinas s?o preferencialmente absorvidas pela mucosa g?strica.

Made available in DSpace on 2016-04-28T14:59:45Z (GMT). No. of bitstreams: 1 2008 - Fernanda Nascimento de Godoi.pdf: 4576086 bytes, checksum: a3f0dc242c634f23a23c384810cb8ae4 (MD5) Previous issue date: 2008-02-14 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This work aimed to evaluate intake in athletic horses fed diets with soybean oil inclusion and the effects of apparent digestibility of nutrients, digestive kinetics, faeces characters and physiologic, hematological and biochemical parameters and. In first essay, fifteen horses were used in a completely randomized design with three diets and five repetitions. Diets used were: diet without soybean oil inclusion (control); diet with inclusion of 8.5% soybean oil; diet with inclusion of 19.5% soybean oil. Trial had 34 days of duration, 30 days to adaptation of diets and four days to samples collection. Kinetics of liquid phase of digesta was estimated by LIPE? (Isolated Lignin Purified Enriched) in liquid form. The LIPE? was given only one time by oral infusion in 30th day of essay and faeces samples were collected at 2, 4, 8, 12, 16, 20, 24, 30, 36, 42, 48, 54, 60, 66, 72 and 78 hours after. Faeces characteristics were evaluate on 33th and 34th day of essay. Blood samples were taken before and at 34th day. Data were submitted to variance analysis and means compared by Student Newman-Keuls test, at 5% of significance. In secund essay, twelve horses were used in a completely randomized design with two diets and six repetitions. Diets used were: diet without soybean oil inclusion (control); diet with inclusion of 10% soybean oil. The trial had 82 days of duration, with three physical effort tests before, at 60th and at 82th day of trial. Heart frequency and body temperature were evaluation and blood samples for analyze of hematological and biochemical parameters were taken in five moments in function of physical effort tests. The first data collection, before the test, with horses at rest, and immediately after the test, and 10, 20 and 120 minutes after the physical effort tests. Data were submitted to non parametric analysis, at 5% of significance. There was a significant reduction of dry matter intake in horses fed high fat diet. Apparent digestibility of fat increased in high fat diets (P<0.05) and apparent digestibility of cellulose decrease (P>0.05) in diet with 19.5% soybean oil inclusion. Apparent digestibility of others nutrients, except crude protein, digestive kinetics and faeces characteristics were not affecting (P>0.05) in horses fed diets with soybean oil inclusion. Horses fed high fat diet increased (P<0.05) in blood level of erythrocytes, hemoglobin and triglycerides and reduction of mean corpuscular volume. Soybean oil in diets did not affect physiological, hematological and biochemical parameters along the time intake time and in function physical effort tests. High fat diets were palatable and safety without any colic or diarrheas cases. The soybean oil can used in diet for horses, reducing dry matter intake and increasing energy density of diets that is interesting to athletic horses / Objetivou-se avaliar o consumo de dietas com diferentes n?veis de inclus?o de ?leo de soja por eq?inos atletas e os efeitos na digestibilidade aparente dos nutrientes, cin?tica digestiva, caracter?sticas fecais, nos par?metros fisiol?gicos, hematol?gicos e bioqu?micos. No primeiro ensaio foram utilizados quinze eq?inos em delineamento experimental inteiramente casualizado com tr?s dietas e cinco repeti??es. As dietas utilizadas foram: dieta sem inclus?o de ?leo de soja (controle); dieta com inclus?o de 8,5% de ?leo de soja; dieta com inclus?o de 19,5% de ?leo de soja. O ensaio teve dura??o de 34 dias, sendo 30 dias de adapta??o dos eq?inos ?s dietas e quatro dias de coleta de amostras. A cin?tica da fase l?quida da digesta foi estimada pelo LIPE? (Lignina Isolada, Purificada e Enriquecida) na forma l?quida, fornecido no 30? dia de ensaio, em dose ?nica, e as amostras fecais foram coletadas nos tempos 0, 2, 4, 8, 12, 16, 20, 24, 30, 36, 42, 48, 54, 60, 66, 72 e 78 horas ap?s o fornecimento. As caracter?sticas fecais foram avaliadas no 33? e 34? dia e, as coletas das amostras sang??neas no in?cio e 34? dia do ensaio. Os resultados foram submetidos ? an?lise de vari?ncia e as m?dias comparadas pelo teste Student Newman-Keuls, com n?vel de signific?ncia de 5%. No segundo ensaio foram utilizados doze eq?inos em delineamento experimental inteiramente casualizado com duas dietas e seis repeti??es. As dietas utilizadas foram: dieta sem inclus?o de ?leo de soja (controle); dieta com inclus?o de 10% de ?leo de soja. O ensaio teve a dura??o de 82 dias, com a realiza??o de tr?s testes de esfor?o f?sico ao in?cio, 60? e 82? dia. Nesses testes foram avaliadas freq??ncia card?aca e temperatura corporal e coletadas amostras de sangue para an?lises hematol?gicas e bioqu?micas. A primeira coleta de dados ocorreu antes do teste, com os eq?inos em repouso e, imediatamente, 10, 20 e 120 minutos ap?s o t?rmino dos testes de esfor?o f?sico. Os valores m?dios dos par?metros fisiol?gicos, hematol?gicos e bioqu?micos foram submetidos ? an?lise n?o param?trica, a 5% de signific?ncia. Houve redu??o significativa no consumo de mat?ria seca das dietas com a inclus?o de ?leo de soja. O coeficiente de digestibilidade aparente do extrato et?reo aumentou (P<0,05) nas dietas hiperlipid?micas e o coeficiente de digestibilidade da celulose reduziu com a inclus?o de 19,5% de ?leo de soja. A digestibilidade dos demais nutrientes, exceto da prote?na bruta, a cin?tica da digesta no trato gastrointestinal e as caracter?sticas fecais n?o foram alteradas (P>0,05) pela inclus?o de ?leo nas dietas. Os eq?inos consumindo as dietas hiperlipid?micas apresentaram aumento (P<0,05) nos n?veis sang??neos de eritr?citos, hemoglobina e triglicer?dios e redu??o no volume corpuscular m?dio. N?o houve altera??o nos par?metros fisiol?gicos, hematol?gicos e bioqu?micos dos eq?inos alimentados com a dieta hiperlipid?mica ao longo do tempo de consumo das dietas e em fun??o dos testes de esfor?o f?sico. As dietas mostraram-se palat?veis e seguras, sem ocorr?ncia de casos de c?licas ou diarr?ias. O ?leo de soja pode ser utilizado nas dietas de eq?inos atletas visando suprir a demanda energ?tica e reduzir o consumo de mat?ria seca, desej?vel em eq?inos da modalidade esportiva Concurso Completo de Equita??o.

Made available in DSpace on 2014-12-17T15:42:04Z (GMT). No. of bitstreams: 1 KeilaROM.pdf: 1106532 bytes, checksum: 919e086ca601ac57108653607838c88e (MD5) Previous issue date: 2008-11-10 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Leather tanneries generate effluents with high content of heavy metals, especially chromium, which is used in the mineral tanning process. Microemulsions have been studied in the extraction of heavy metals from aqueous solutions. Considering the problems related with the sediment resulting from the tanning process, due to its high content in chromium, in this work this sediment was characterized and microemulsion systems were applied for chromium removal. The extraction process consists in the removal of heavy metal ions present in an aqueous feeding solution (acid digestion solution) by a microemulsion system. First three different solid sludge digestion methods were evaluated, being chosen the method with higher digestion capacity. For this digestion method, seeking its optimization, was evaluated the influence of granule size, temperature and digestion time. Experimental results showed that the method proposed by USEPA (Method A) was the most efficient one, being obtained 95.77% of sample digestion. Regarding to the evaluated parameters, the best results were achieved at 95?C, 14 Mesh granule size, and 60 minutes digestion time. For chromium removal, three microemulsion extraction methods were evaluated: Method 1, in a Winsor II region, using as aqueous phase the acid digestion solution; Method 2, in a Winsor IV region, being obtained by the addition of the acid digestion solution to a microemulsion phase, whose aqueous phase is distilled water, until the formation of Winsor II system; and Method 3, in a Winsor III region, consisting in the formation of a Winsor III region using as aqueous phase the acid digestion solution, diluted in NaOH 0.01N. Seeking to optimize the extraction process only Method 1 (Systems I, II, and VIII) and Method 2 (System IX) were evaluated, being chosen points inside the interest regions (studied domains) to study the influence of contact time and pH in the extraction percentiles. The studied systems present the following compositions: System I: Surfactant Saponified coconut oil, Cosurfactant 1-Butanol, Oil phase Kerosene, Aqueous phase 2% NaCl solution; System II: Aqueous phase Acid digestion solution with pH adjusted using KOH (pH 3.5); System VIII: Aqueous phase - Acid digestion solution (pH 0.06); and System IX Aqueous phase Distilled water (pH 10.24), the other phases of Systems II, VIII and IX are similar to System I. Method 2 showed to be the more efficient one regarding chromium extraction percentile (up to 96.59% - pH 3.5). Considering that with Method 2 the microemulsion region only appears in the Winsor II region, it was studied Method 3 (System X) for the evaluation and characterization of a triphasic system, seeking to compare with a biphases system. System X is composed by: Surfactant Saponified coconut oil, Cosurfactant 1-Butanol, Oil phase Kerosene, Aqueous phase Acid digestion solution diluted with water and with its pH adjusted using 0.01N NaOH solution. The biphasic and triphasic microemulsion systems were analyzed regarding its viscosity, extraction efficiency and drop effective diameter. The experimental results showed that for viscosity studies the obtained values were low for all studied systems, the diameter of the drop is smaller in the Winsor II region, with 15.5 nm, reaching 46.0 nm in Winsor III region, being this difference attributed to variations in system compositions and micelle geometry. In chromium extraction, these points showed similar results, being achieved 99.76% for Winsor II system and 99.62% for Winsor III system. Winsor III system showed to be more efficient due to the obtaining of a icroemulsion with smaller volume, with the possibility to recover the oil phase in excess, and the use of a smaller proportion of surfactant and cosurfactant (C/S) / Os curtumes geram efluentes carregados em metais pesados, especialmente o cromo, utilizado no processo de curtimento. Microemuls?es t?m sido estudadas na remo??o de metais pesados. Considerando o problema encontrado no sedimento gerado no processo de curtimento, pelo elevado teor de cromo, no presente trabalho nos propomos a caracteriz?-lo e aplicar sistemas microemulsionados para remo??o do cromo. O processo de extra??o consiste em remover o metal de uma alimenta??o aquosa (solu??o ?cida digerida) para uma fase microemuls?o. Iniciou-se a pesquisa avaliando tr?s diferentes m?todos de digest?o de sedimentos, escolhendo-se o m?todo que apresentasse maior percentual de digest?o, sendo este m?todo otimizado atrav?s de mudan?as no di?metro das part?culas do sedimento, tempo e temperatura de digest?o. Nesse estudo, escolheu-se o m?todo proposto pelo EPA (M?todo A), que se mostrou mais eficiente, obtendo-se um percentual de 95,77% de digest?o da amostra. Com rela??o aos par?metros avaliados, os melhores resultados foram obtidos com a temperatura a 95?C, granulometria de 14 Mesh e tempo de opera??o de 60 minutos. Para os estudos da extra??o foram utilizados tr?s m?todos: o M?todo 1, que consiste na forma??o de uma regi?o de Winsor II, utilizando a solu??o ?cida digerida como fase aquosa; o M?todo 2, que consiste em utilizar uma microemuls?o cuja fase aquosa ? ?gua destilada e adicionar a solu??o ?cida digerida at? a obten??o de um sistema de Winsor II; e o M?todo 3, que consiste na forma??o de uma regi?o de Winsor III, utilizando a solu??o ?cida digerida, dilu?da em NaOH 0,01N, como fase aquosa. Para o estudo da otimiza??o da extra??o foram avaliados apenas os M?todos 1 (Sistemas I, II e VIII) e 2 (Sistema IX), escolhendo-se pontos dentro das regi?es de interesse (dom?nio estudado) para estudar a influ?ncia do tempo e do pH no percentual de extra??o. Os sistemas estudados apresentam as seguintes composi??es: Sistema I: Tensoativo ?leo de coco saponificado, Cotensoativo 1-Butanol, Fase oleosa Querosene, Fase aquosa NaCl 2,0%; Sistema II: Fase aquosa Solu??o ?cida digerida ajustada c/ KOH (pH 3,5); Sistema VIII: Fase aquosa Solu??o ?cida digerida (pH 0,06) e Sistema IX: Fase aquosa ?gua destilada (pH 10,24), as demais fases dos Sistemas II, VIII e IX s?o semelhantes ao Sistema I. Atrav?s desse estudo, observou-se que o M?todo 2 foi mais eficiente, com percentuais de 96,59% de extra??o, em pH 3,5. Tendo em vista que com a aplica??o do M?todo 2 s? se obt?m os sistemas de Winsor II, estudou-se um sistema capaz de fornecer a regi?o de Winsor III (tr?s fases) para efeito de compara??o da efici?ncia na extra??o do cromo, com um sistema de duas fases (Winsor II) e, assim, constituiu-se o M?todo 3, utilizando o Sistema X. O sistema X apresenta a seguinte composi??o: Tensoativo ?leo de coco saponificado, Cotensoativo 1-Butanol, Fase oleosa Querosene, Fase aquosa Solu??o ?cida digerida dilu?da em ?gua e ajustado com NaOH 0,01N. As microemuls?es nas regi?es bif?sicas e trif?sicas foram analisadas com rela??o ? viscosidade, extra??o e di?metro efetivo da gota. Os resultados obtidos nas regi?es de W II e WIII foram os seguintes: a viscosidade ? baixa em todos os pontos estudados e o comportamento dos fluidos ? do tipo Newtoniano; o di?metro da gota ? menor na regi?o de Winsor II, com di?metro de 15,5 nm, atingindo 46 nm em Winsor III, sendo essa varia??o atribu?da ?s composi??es estudadas e ? geometria da micela; os resultados obtidos na extra??o com os dois sistemas foram semelhantes, com 99,76% de extra??o em WII e 99,62 % em WIII. O sistema utilizando WIII mostrou-se mais eficiente na extra??o do cromo devido a obten??o de uma microemuls?o com menor volume, a possibilidade de recuperar o ?leo em excesso e a utiliza??o de uma menor propor??o de cotensoativo e tensoativo (C/T)

Made available in DSpace on 2014-12-17T14:08:52Z (GMT). No. of bitstreams: 1 IzabelKVS_DISSERT.pdf: 849654 bytes, checksum: e754d8d3077394e35fc6004a18238827 (MD5) Previous issue date: 2012-12-14 / This project describes a methodology optimization that would allow for a more efficient microwave assisted digestion process for petroleum samples. With the possible chance to vary various factors at once to see if any one factor was significant enough in the answers, experimental planning was used. Microwave assisted digestion allows, through the application of potency, an increasing number of collisions between the HNO3 and H2O2 molecules, favoring sample opening for complex matrixes. For this, a 24 factorial experimental planning was used, varying potency, time and the volumes for HNO3 65% and H2O2 30%. To achieve the desired answers, several elements were monitored (C, Cu, Cr, Fe, Ni, Zn and V) through Inductively coupled plasma atomic emission spectroscopy (ICP-OES). With this initial study it was noticed that the HNO3 was not a significant factor for any of the statistical studies for any of the analytes and the other 3 factors and their interactions showed statistical significance. A Box Behnken experimental planning was used taking in consideration 3 factors: H2O2 volume, time (min) and Potency (W), Nitric Acid kept at 4mL for a mass of 0,1g of petroleum. The results were extremely satisfying showing higher efficiency in the digestion process and taking in a responsibility between the answers for each analyte and the carbon monitoring was achieved in the following conditions: 7mL of H2O2, 700 Watts of potency and a reaction time of 7 minutes with 4mL de HNO3 for a mass of 0,1g of petroleum. The optimized digestion process was applied to four different petroleum samples and the analytes determined by ICP-OES / Este trabalho teve como objetivo a otimiza??o de uma metodologia que possibilite maior efici?ncia no processo de digest?o auxiliada por forno microondas para amostras de petr?leo. Um planejamento experimental multivariado foi realizado, num intuito de observar todos os fatores ao mesmo tempo e suas intera??es, para saber se determinado fator tem influ?ncia significativa sobre a resposta. A digest?o auxiliada por microondas permite, atrav?s da aplica??o de pot?ncia, tornar maior o n?mero de colis?es entre as mol?culas do HNO3 e do H2O2 no meio reacional, favorecendo a abertura de amostras de matrizes complexas. Dessa forma, foi realizado um planejamento fatorial 24 variando a pot?ncia, o tempo e os volumes de HNO3 65% V/V e H2O2 30% V/V. Para obter as respostas, foram monitorados diversos elementos (C, Cu, Cr, Fe, Ni, Zn e V) por espectrometria de emiss?o ?tica com plasma indutivamente acoplado (ICP-OES). Com este estudo inicial foi observado que o volume de HNO3 n?o foi um fator significativo estatisticamente para nenhum dos analitos estudados e que os outros tr?s fatores e suas intera??es apresentaram signific?ncia estat?stica. Um segundo planejamento do tipo Box Behnken foi realizado considerando os 3 fatores: volume de H2O2, tempo (min) e pot?ncia (W), o volume de ?cido n?trico foi mantido em 4 mL para uma massa de 0,1g de petr?leo. Os resultados foram bastante expressivos, a maior efici?ncia de digest?o, assumindo um compromisso entre as respostas obtidas para cada analito e o monitoramento do carbono, foi obtido nas condi??es de 7 mL de H2O2, 700 W de pot?ncia e 7 min de tempo de rea??o com 4 mL de HNO3 para uma massa de 0,1 g de petr?leo. O procedimento de digest?o otimizado foi aplicado a quatro diferentes amostras de petr?leo e os analitos determinados por ICP OES