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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.
71

Desenvolvimento de membranas de poliuretano com rapamicina e seu potencial uso em regenera??o vascular

Cabral, Emanuelli Louren?o 19 April 2016 (has links)
Submitted by Salete Sartori (ssartori@pucrs.br) on 2017-01-16T13:46:11Z No. of bitstreams: 1 DIS_EMANUELLI_LOURENCO_CABRAL_COMPLETO.pdf: 2324920 bytes, checksum: cdf79816569d7d9b352a5a2d9b93437f (MD5) / Made available in DSpace on 2017-01-16T13:46:11Z (GMT). No. of bitstreams: 1 DIS_EMANUELLI_LOURENCO_CABRAL_COMPLETO.pdf: 2324920 bytes, checksum: cdf79816569d7d9b352a5a2d9b93437f (MD5) Previous issue date: 2016-04-19 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The use of biomaterials that can replace or restore damaged tissues in the human body is necessary to improve the quality and life expectancy of the population. In this sense, the present project aims the study and development of different membranes based on biostable polyurethane, the incorporation of rapamycin, an antithrombogenic drug that can help about the inhibition of blood vessel narrowing, and the evaluation to verify its potential application in vascular area. Therefore, the obtained membranes showed three different morphologies, a membrane with porous surface (average pore size 3,3 ?m ? 0,8 ?m) ? named porous PU ? other membrane with an irregular surface, but without porous ? dense PU ? and for the last, a membrane with internal interconnections ? leached PU. There were realized for each membrane the tests of wettability and contact angle. The leached PU showed higher average of body fluid absorption and porous PU showed higher hydrophilicity, however after the addition of rapamycin, dense PU showed more hydrophilicity. About calcification test, both of three membranes showed minerals deposition, but this did not happen with dense PU after incorporation of drug. The thermal characterizations of the membranes were according with literature for polyurethanes, as the mechanical behavior. Lastly, the membranes did not showed in vitro cytotoxicity, which means that they could be used within our bodies. Thus, the obtained membranes showed their interesting and high potential for use and improvement / O uso de biopol?meros que possam substituir ou restaurar tecidos danificados no corpo humano ? necess?rio para a melhoria na qualidade e expectativa de vida da popula??o. Neste sentido, o presente projeto visa o estudo e desenvolvimento de diferentes membranas baseadas em poliuretano bioest?vel, a incorpora??o da rapamicina, um f?rmaco antitrombog?nico que pode auxiliar na inibi??o do estreitamento dos vasos sangu?neos, e a avalia??o para verificar sua potencial aplica??o na ?rea vascular. Sendo assim, as membranas obtidas apresentaram tr?s morfologias distintas, uma membrana com superf?cie totalmente porosa (tamanho m?dio de poros de 3,3 ?m ? 0,8 ?m) ? denominada PU poroso ? outra com irregularidades em sua superf?cie, por?m sem poros ? PU denso ? e por fim, uma membrana com interconex?es internas ? PU lixiviado. Para cada membrana foram realizados ensaios como teste de inchamento e an?lise do ?ngulo de contato. O PU lixiviado apresentou maior m?dia de absor??o de fluido corp?reo e o PU poroso apresentou maior hidrofilicidade, contudo, ap?s a adi??o da rapamicina o PU denso mostrou-se mais hidrof?lico. Em rela??o ao teste de calcifica??o, as tr?s membranas apresentaram dep?sito de minerais, o que n?o ocorreu para o PU denso ap?s a adi??o do f?rmaco. As caracteriza??es t?rmicas das membranas mostraram-se de acordo com a literatura para poliuretanos, assim como o comportamento mec?nico. Por fim, os estudos de citotoxicidade mostraram que as membranas n?o s?o citot?xicas, podendo ser utilizadas dentro do nosso organismo. Dessa maneira, as membranas obtidas mostram-se interessantes e com grande potencial de uso e aperfei?oamento
72

O uso de subst?ncias psicoativas na adolesc?ncia e a rela??o com as atitudes parentais

Cerutti, Fernanda 10 January 2014 (has links)
Made available in DSpace on 2015-04-14T13:22:17Z (GMT). No. of bitstreams: 1 453494.pdf: 137289 bytes, checksum: 208aa3a6c649d00d027ac69e122691b6 (MD5) Previous issue date: 2014-01-10 / The general goal of this thesis was to investigate the relation between parental attitudes and drug abuse in adolescence. For that, it was carried out one theoretical study and one empirical; both have been presented as scholarly papers. By means of a systematic literature review, the theoretical study aimed to do an overview of the impacts that parent-child relation have on adolescents‟ development, regarding drug abuse. The studies included in the literature review covers a sample with a meaningful number of participants representing different countries. So, findings points out that parental attitudes represents a model for the child, also observing their attitudes, demonstrate affection and have a close relationship are effectiveness in prevention of drug abuse in adolescence. Additionally, the empirical study aimed to analyze the relation between adolescents' perceptions of parental attitudes and their trend to psychoactive substances abuse. For this purpose, a quantitative cross-sectional study was carried out; it composes a sample of 487 adolescents attending the last years of primary school and high school from public and private schools from the countryside in Rio Grande do Sul. All participants have completed a socio-demographic questionnaire - the ASSIST which investigates the drug abuse, and the PBI about adolescents' perceptions of parental attitudes. For statistical analysis, in addition to the descriptive analysis, it was applied the Multinomial Logistic Regression model adjusted with the Stepwise method, which have proposed models giving the probability of association between categories: no use; use; abuse and dependence of the nine drugs included in the study, with some socio-demographic data and with parenting styles and types of mother and father bonds. The Cronbach alpha coefficient was used to estimate the reliability of the questionnaires. Also, the models covered by the analysis were adjusted to three classes of drugs: tobacco, alcohol and marijuana. And, for each drug category were linked variables with higher influence in the use, abuse or dependence of the substance. Moreover, it was found that parenting style, affection or controlling (from mother or father), was presented in the three models. Summing up, the findings have shown the importance of studies analyzing the relation between drug abuse in adolescence and the adolescents' perceptions of parental attitudes. / O objetivo geral desta disserta??o foi investigar a rela??o entre o uso de drogas na adolesc?ncia e as atitudes parentais. Para isso, foram realizados dois estudos, um te?rico e um emp?rico, apresentados na forma de artigos. O artigo te?rico buscou, a partir de uma revis?o sistem?tica da literatura, um panorama geral dos impactos que a rela??o entre pais e filhos tem no desenvolvimento do adolescente, no que diz respeito ao uso de drogas. Os estudos inclu?dos na revis?o abarcam uma amostra com n?mero significativo de participantes e com uma representa??o de diferentes pa?ses. Os resultados apontam que as atitudes dos pais servem de modelo para o filho e que seu monitoramento, afeto e rela??o pr?xima s?o fatores preventivos para o uso de drogas na adolesc?ncia. O artigo emp?rico teve como objetivo investigar a rela??o entre o uso de drogas na adolesc?ncia e a percep??o sobre as atitudes parentais. Para tanto, foi realizada uma pesquisa de m?todo quantitativo transversal, com uma amostra de 487 adolescentes estudantes de escolas p?blicas e privadas de um munic?pio do interior do RS e que estavam frequentando os ?ltimos anos do ensino fundamental e os tr?s anos do ensino m?dio. Todos os participantes responderam a um question?rio sociodemogr?fico ao Alcohol, Smoking and Substance Involvement Screening Test (ASSIST) que investiga o uso de drogas e ao Parental Bonding Instrument (PBI) que trata da percep??o do adolescente sobre as atitudes de seus pais. Para an?lise estat?stica, al?m da an?lise descritiva, foi utilizado o Modelo Log?stico Multinomial Nominal, ajustado com o m?todo Stepwise, que prop?s modelos que d?o a probabilidade de associa??o entre as categorias: n?o uso, uso, abuso e depend?ncia das nove drogas contempladas no estudo, com alguns dados sociodemogr?ficos, com os estilos parentais e tipos de v?nculos da m?e e do pai. O coeficiente alfa de Cronbach foi utilizado para estimar a confiabilidade dos question?rios aplicados. Os modelos contemplados pela an?lise foram ajustados para tr?s classes de drogas que s?o o tabaco, o ?lcool e a maconha. Para cada uma dessas drogas, foram relacionadas as vari?veis com maior influ?ncia, no uso, abuso ou depend?ncia de cada subst?ncia. Verificou-se que o estilo parental, afeto ou controle, da m?e ou do pai, esteve contemplado nos tr?s modelos. A partir dos achados, detectou-se a import?ncia de estudos que objetivem analisar a rela??o entre o uso de drogas na adolesc?ncia e a percep??o do jovem no tocante ?s atitudes parentais.
73

O sujeito ps?quico e a condi??o de servid?o ao objeto-droga : do rigor da psican?lise ? pesquisa na escuta

Dockhorn, Carolina Neumann de Barros Falc?o 10 March 2014 (has links)
Made available in DSpace on 2015-04-14T13:22:19Z (GMT). No. of bitstreams: 1 456258.pdf: 326164 bytes, checksum: 4d80c19cc789dadf3190298918876566 (MD5) Previous issue date: 2014-03-10 / The global fight against drug consumption and its devastating effects has already spanned throughout many decades. Indicators of production and consumption of psychoactive substances continue to be alarming, since there is an estimate that, by 2010, the number of problematic drug users reached the mark of 27 million people (UNODC, 2012). Since the phenomenon of Drug Addiction/Substance Abuse is fully aligned with the frantic search for substances that relieve the discomfort, one needs to recognize the heterogeneity of the use, of the understanding and of the intervention of this phenomenon. We opted, in this PhD thesis for, from the epistemological perspective of psychoanalysis, considering modalities of drug use involving a state of slavery of the subject(s) to the elected substance(s). Throughout the Thesis, we use the classification already established - Drug Addiction because it highlights essential points of the phenomenon as a pathological dependence, in which the subject cannot do without the drug-object and a choice uniquely marked by precariousness of himself in a psychic economy mainly composed of death instincts. Being the contribution to the Psychoanalytic Metapsychology its aim, questioning the choice of object-drug, its dynamics and its role in the psychic economy from the effects of the subject's history. This Thesis is organized in four sections, being two of which theoretical and two empirical. The first section proposes theoretical characterizations of the notion of subject throughout History. Its main objective was to characterize the epistemological break produced by the advent of Psychoanalysis and the expansion of the notion of subject caused by it. It also questioned discomfort settings that affect the contemporary subject and the risks that arise from the understanding that reduces human phenomena to a normative model of psychopathology. The second theoretical section concerns the presentation of the research strategy design built throughout the layout of this research. Built on the Psychoanalytic Method, the proposition of the Clinical-Interpretative Strategy rests on the consideration that the Listening is a broader process than the stricto sensu psychoanalytic clinics. The stages of Clinical-Interpretative Strategy are presented, fostering it as a valid resource for the psychoanalytic research in the Academy. The third section is an empirical study conducted with seven drug addicts, located according to convenience. Each participant of the study was heard by a psychoanalyst in a series of interviews, which were analyzed in the light of Clinical-Interpretative Strategy. Significant differences were identified in terms of investments from participants with regard to the choice and the function of the object-drug, which led to the proposition of two defensive resources, called autoerotic servitude and narcissistic servitude. The fourth and last section presents a second empirical study through the case study of a participant whose story allowed us question the concept of narcissism and its positive and negative aspects, how the negative side works and its relationship with the addiction. The results obtained allow us to claim to be the Clinical-Interpretative Strategy a legitimate alternative to the research with the Psychoanalytic Method contemplating its rigor and specificity. Furthermore, it is considered that the proposal of the notions of autoerotic servitude and narcissistic servitude offers an important contribution to Metapsychology, highlighting different nuances in terms of ego investment present in the psychic and dynamic economy of Drug Addiction / O combate mundial ao avan?o das drogas e seus efeitos devastadores j? atravessa muitas d?cadas. Os indicadores de produ??o e consumo de subst?ncias psicoativas seguem alarmantes, pois se estima que, em 2010, o n?mero de usu?rios problem?ticos de drogas alcan?ava cerca de 27 milh?es de pessoas (UNODC, 2012). Sendo o fen?meno da Drogadi??o/Toxicomania totalmente alinhado ? busca fren?tica por subst?ncias que aliviem o mal-estar, ? preciso reconhecer a heterogeneidade do uso, da compreens?o e da interven??o sobre esse fen?meno. Optou-se, nessa Tese de Doutorado por, desde a perspectiva epistemol?gica da Psican?lise, contemplar modalidades de uso de drogas que envolvam um estado de escravid?o do sujeito ?(s) subst?ncia(s) eleita(s). Ao longo da Tese, utilizam-se as nomenclaturas j? consagradas Drogadi??o ou Toxicomania por ressaltarem pontos essenciais do fen?meno como a depend?ncia patol?gica, na qual o sujeito n?o pode prescindir do objeto-droga e a elei??o singular marcada pela precariedade do si mesmo em uma economia ps?quica predominantemente tan?tica. Objetivou-se contribuir com a Metapsicologia Psicanal?tica, problematizando a elei??o do objeto-droga, sua din?mica e sua fun??o na economia ps?quica a partir dos efeitos da hist?ria do indiv?duo. Esta Tese est? organizada em quatro se??es, sendo duas de cunho te?rico e duas de cunho emp?rico. A primeira se??o te?rica prop?e caracteriza??es de no??o de sujeito ao longo da Hist?ria. Seu objetivo principal foi caracterizar a ruptura epistemol?gica produzida pelo advento da Psican?lise e a amplia??o da no??o de sujeito provocada por ela. Problematizou, tamb?m, as configura??es de mal-estar que acometem o sujeito contempor?neo e os riscos oriundos da leitura que reduz os fen?menos humanos a um modelo normativo de psicopatologia. A segunda se??o te?rica diz respeito ? apresenta??o do delineamento da estrat?gia de investiga??o constru?da ao longo da execu??o desta pesquisa. Sustentada no M?todo Psicanal?tico, a proposi??o da Estrat?gia Cl?nico-Interpretativa est? apoiada na considera??o de ser a Escuta um processo mais amplo que a cl?nica psicanal?tica stricto sensu. Apresentam-se as etapas da Estrat?gia Cl?nico-Interpretativa, sustentando-a como um recurso v?lido ? pesquisa psicanal?tica na Academia. A terceira se??o ? um estudo emp?rico, realizado com sete participantes toxic?manos, localizados por conveni?ncia. Cada participante foi escutado por um psicanalista em um conjunto de entrevistas, as quais foram analisadas ? luz da Estrat?gia Cl?nico-Interpretativa. Identificaram-se importantes diferen?as nas modalidades de investimentos dos participantes em rela??o ? elei??o e ? fun??o do objeto-droga, o que levou ? proposi??o de dois recursos defensivos, denominados servid?o autoer?tica e servid?o narc?sica. A quarta e ?ltima se??o apresenta um segundo estudo emp?rico realizado atrav?s do Estudo de Caso de uma participante, cuja hist?ria permitiu problematizar o conceito de narcisismo em suas vertentes positiva e negativa, o trabalho do negativo e sua rela??o com a Toxicomania. Os resultados obtidos permitem afirmar ser a Estrat?gia Cl?nico-Interpretativa uma leg?tima alternativa ? pesquisa com o M?todo Psicanal?tico contemplando seu rigor e sua especificidade. Considera-se, ainda, que a proposi??o das no??es de servid?o autoer?tica e narc?sica oferecem uma importante contribui??o ? Metapsicologia, destacando nuances diferentes nas modalidades de investimento do Eu presentes na economia e din?mica ps?quica da Drogadi??o.
74

A terapia multifamiliar e a depend?ncia qu?mica

Seadi, Susana Maria Sastre 07 March 2007 (has links)
Made available in DSpace on 2015-04-14T13:22:37Z (GMT). No. of bitstreams: 1 391021.pdf: 1221227 bytes, checksum: b7256848cfc1c481bc804f1e84e7cf9e (MD5) Previous issue date: 2007-03-07 / A depend?ncia qu?mica ? um fen?meno multifatorial e necessita de distintas abordagens terap?uticas. A inclus?o da fam?lia, n?o como coadjuvante ou colaboradora, mas como parte do tratamento dos problemas com ?lcool e outras drogas vem crescendo no Brasil nos ?ltimos anos. No entanto, s?o poucos os estudos sobre os fatores que podem contribuir para a ades?o ao tratamento e o presente trabalho se prop?e a verificar a influ?ncia da participa??o da fam?lia na ades?o ao tratamento. Esta disserta??o compreende dois estudos, decorrentes do projeto de pesquisa, sendo um de revis?o te?rica e outro de cunho emp?rico, ambos discorrendo sobre a import?ncia da fam?lia no tratamento da depend?ncia qu?mica. No estudo te?rico, ? luz do paradigma sist?mico realizou-se uma revis?o de estudos sobre fam?lia, interven??es focadas na fam?lia, e preval?ncia do uso de subst?ncias atrav?s de buscas nas bases de dados, PsycInfo, ProQuest, Scielo e Medline, Web of Science, e Lilacs, entre 1996 e 2006 selecionados abstracts, dos quais foram definidos artigos para a obten??o e leitura na ?ntegra, acrescidos de cap?tulos de livros adquiridos atrav?s de consultas em livrarias, bibliotecas, e via internet e, uma tese de doutorado. Os descritores utilizados foram family, multi-family groupy therapy, treatment,drugs, substance abuse, drugs abuse, treatment,intake, inpatient e nas bases de l?ngua portuguesa, os descritores, foram: fam?lia, terapia de grupo multifamiliar, tratamento, drogas, abuso de subst?ncias, interna??o e depend?ncia qu?mica O segundo, ? um estudo retrospectivo envolvendo fam?lias que participaram do grupo de terapia multifamiliar em uma unidade de depend?ncia qu?mica de uma cl?nica privada, na cidade de Porto Alegre. Essa amostra refere-se aos pacientes que estiveram internados no per?odo entre 1997 e 2003, totalizando 672 fam?lias. A amostra ? composta predominantemente de homens, e com maior preval?ncia de depend?ncia de ?lcool. Os resultados mostraram que h? associa??o entre a participa??o dos familiares e uma maior ades?o ao tratamento
75

Purifica??o de glicerol utilizando diferentes adsorventes: An?lise t?cnica e termodin?mica / Glycerol purification using different adsorbents: Technical and thermodynamic analysis

ALVES, Amanda de Paula 23 February 2017 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-09-12T19:05:23Z No. of bitstreams: 1 2017 - Amanda de Paula Alves.pdf: 2949048 bytes, checksum: 68f405efb8be6119401dfd85e1d5768a (MD5) / Made available in DSpace on 2017-09-12T19:05:23Z (GMT). No. of bitstreams: 1 2017 - Amanda de Paula Alves.pdf: 2949048 bytes, checksum: 68f405efb8be6119401dfd85e1d5768a (MD5) Previous issue date: 2017-02-23 / The large amount of glycerol, produced in the last decades, generated as a by product of biodiesel production is object of inumerous studies searching for different technologies for its purification. Crude glycerol obtained as a by-product in the transesterification process is composed of alcohol, water, inorganic salts, free fatty acids, mono-, di-, triglycerides, among other organic materials and wastes in different concentrations. It is of extreme importance the purification of glycerol in order to reduce environmental problems due to its accumulation. There are current effective technologies in purifying and refining crude glycerol. However, they are considered unfeasible for small and medium production units due to the high cost and high energy demand. In this way, it is essential that new purification routes of low cost and high efficiency, as well as new markets, be developed. The adsorption process is promising and very favorable technique to remove the contaminants from glycerin due to its low cost, simplicity of design and operation. In this point of view, the objective of this work was to select an adsorbent for the purification of crude glycerol obtained from the transesterification reaction of residual oil. The evaluation of the efficiency and the best operacional conditions were studied using three types of adsorbents: Pure-Flo Supreme B81 clarifying clay, activated charcoal and diatomaceous earth. Preliminary adsorption experiments were carried out using a synthetic solution of glycerin and soybean oil, in order to verify the influence of glycerin concentration in the solution, as well as the behavior of the glycerol contaminants in the adsorption process. In order to reach the objective, the influence and optimization of the process variables as temperature (298.15, 305.65 and 313.15 K), amount of adsorbent (1.2, 1.8 and 2.4 g) and glycerol concentration (30, 50 and 70% v/v) were evaluated through an experimental design. The most significant variable was glycerol concentration, and results indicated high glycerol content after purification: 97.25% for diatomaceous earth, 95.59% for activated carbon and 90.26% for clay. Through the optimization of these variables, experiments were carried out to study the thermodynamics and kinetics of the reaction. The equilibrium time was less than 60 minutes for the three adsorbents. The negative values of Gibbs free energy (?G) showed that the adsorption of the contaminants is a spontaneous process. The negative values for enthalpy change (?H) and positive entropy (?S) values for clay and activated carbon indicate an exothermic nature and that the contaminant molecules are more randomnless in the adsorbed state than in solution. The positive value of ?H for diatomaceus earth indicates that the adsorption process for this adsorbent is endothermic. The adsorption results obtained at 298.15, 305.65 and 313.15 K showed that the experimental data were well correlated with the Langmuir, Freundlich and Redlich-Peterson isotherms models. The purification of crude glycerol using the same adsorbents did not show an effective result. The results showed that the adsorbents were not able to adsorb the impurities, but rather a small amount of glycerol. The adsorption carried out for purification did not clarify the glycerin, concluding that only the adsorption process is not suitable for purification of the crude glycerol, and a pre-purification step is necessary for the previous removal of the contaminants. / O excedente de glicerol produzido nas ?ltimas d?cadas, gerado como subproduto da produ??o de biodiesel, est? associado a constantes pesquisas por fontes alternativas de energia e vem criando uma demanda na busca de diferentes tecnologias para sua purifica??o. A glicerina bruta obtida como subproduto no processo de transesterifica??o ? composta por ?lcool, ?gua, sais inorg?nicos, ?cidos graxos livres, mono-, di-, triglicer?deos, entre outras mat?rias org?nicas e res?duos em diferentes quantidades. ? de extrema import?ncia a purifica??o do glicerol, a fim de reduzir problemas ambientais devido ao seu ac?mulo. Existem tecnologias atuais eficazes na purifica??o e refino do glicerol bruto. Por?m, s?o consideradas invi?veis para pequenas e m?dias produ??es, devido ?s restri??es de custos e alta demanda energ?tica. Dessa forma, ? indispens?vel que novas rotas de purifica??o de menor custo e maior efici?ncia, assim como novos mercados, sejam desenvolvidos. A adsor??o desponta como uma t?cnica promissora e muito favor?vel para a remo??o dos contaminantes da glicerina, devido ao seu baixo custo, simplicidade de projeto e opera??o. Diante do exposto, o objetivo deste trabalho foi selecionar um adsorvente para a purifica??o do glicerol bruto obtido da rea??o de transesterifica??o de ?leo residual. Para a avalia??o da efici?ncia e escolha das melhores condi??es de purifica??o, foram avaliados tr?s tipos de adsorventes: argila clarificante Pure-Flo Supreme B81, carv?o ativado e terra diatom?cea. Experimentos de adsor??o foram realizados utilizando uma solu??o sint?tica de glicerina P.A. e ?leo de soja, com o intuito de verificar a influ?ncia da concentra??o da glicerina na solu??o, assim como o comportamento dos contaminantes do glicerol no processo de adsor??o. Para atingir o objetivo, avaliou-se a influ?ncia e otimiza??o das vari?veis de processo como temperatura (298,15, 305,65 e 313,15 K), quantidade de adsorvente (1,2, 1,8 e 2,4 g) e concentra??o de glicerol (30, 50 e 70% v/v) atrav?s de um planejamento experimental. A vari?vel mais significativa foi a concentra??o de glicerol, e resultados indicaram alto teor de glicerol ap?s a purifica??o: 97,25% para terra diatom?cea, 95,59% para carv?o e 90,26% para argila. Al?m disso, foram realizados experimentos para o estudo da termodin?mica e cin?tica da rea??o e o tempo necess?rio para o sistema alcan?ar o equil?brio foi inferior a 60 minutos para os tr?s adsorventes. Os valores negativos da varia??o da energia livre de Gibbs (?G) mostraram que a adsor??o dos contaminantes ? um processo espont?neo. Os valores negativos para varia??o de entalpia (?H) e os valores positivos de entropia (?S) para argila e carv?o ativado, indicam uma natureza exot?rmica e que as mol?culas dos contaminantes encontram-se mais desordenadas no estado adsorvido do que em solu??o. O valor positivo de ?H para a terra diatom?cea indica que o processo de adsor??o para esse adsorvente ? endot?rmico. As an?lises dos resultados de adsor??o obtidos nas temperaturas de 298,15, 305,65 e 313,15 K, mostraram que os dados experimentais foram bem correlacionados ?s isotermas de Langmuir, Freundlich e Redlich Peterson. Utilizando as mesmas vari?veis para o processo de adsor??o usando o glicerol bruto, os resultados mostraram que os adsorventes n?o foram capazes de adsorver as impurezas, mas sim glicerol. A adsor??o realizada para purifica??o n?o clarificou a glicerina, indicando que n?o houve remo??o das impurezas, concluindo que somente o processo de adsor??o n?o ? apropriado para purifica??o do glicerol bruto, sendo necess?rio uma pr?-purifica??o para pr?via remo??o de alguns contaminantes.
76

Produ??o de amilase por Bacillus amyloliquefaciens utilizando torta de maca?ba (Acrocomia aculeata) e farinha de pupunha (Bactris gasipaes) como substratos / Production of amylase by Bacillus amyloliquefaciens using macauba cake (Acrocomia aculeata) and peach palm flour (Bactris gasipaes) as substrates

Silva, Isadora Ferreira da 24 July 2012 (has links)
Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-19T13:03:28Z No. of bitstreams: 5 isadora.pdf: 1113191 bytes, checksum: d7fa6c19b7906bcd17915b6d1233d2e6 (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2110 bytes, checksum: b4c884761e4c6c296ab2179d378436d4 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-20T09:25:04Z (GMT) No. of bitstreams: 5 isadora.pdf: 1113191 bytes, checksum: d7fa6c19b7906bcd17915b6d1233d2e6 (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2110 bytes, checksum: b4c884761e4c6c296ab2179d378436d4 (MD5) / Made available in DSpace on 2015-02-20T09:25:04Z (GMT). No. of bitstreams: 5 isadora.pdf: 1113191 bytes, checksum: d7fa6c19b7906bcd17915b6d1233d2e6 (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2110 bytes, checksum: b4c884761e4c6c296ab2179d378436d4 (MD5) Previous issue date: 2013-02-21 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Funda??o de Amparo ? Pesquisa do estado de Minas Gerais (FAPEMIG) / Amilases s?o enzimas que atuam no rompimento das liga??es glicos?dicas presentes nas cadeias de amilose e amilopectina. As amilases possuem aplica??es em diversas ?reas tais como: ind?stria de papel e celulose, ind?stria t?xtil, ind?stria de detergentes e produtos de limpeza, ind?stria qu?mica e farmac?utica, na produ??o de vitaminas e antibi?ticos. Embora as amilases sejam encontradas em plantas, animais e micro-organismos, as enzimas microbianas geralmente atendem de maneira satisfat?ria ? demanda industrial. As enzimas microbianas podem ser obtidas por meio de processos fermentativos, podendo ser obtidas tanto por cultivo superficial como por cultivos submersos. O presente trabalho teve por objetivo avaliar a produ??o de enzimas amilol?ticas por fermenta??o submersa utilizando Bacillus amyloliquefaciens ATCC 23350 e coprodutos da cadeia produtiva do biodiesel como substrato. A capacidade da produ??o das enzimas amilol?ticas foi testada utilizando como substratos diferentes coprodutos, sendo esses: torta de maca?ba, torta de dend?, farinha de pupunha, torta de mamona e torta de tremo?o. A torta de maca?ba e farinha de pupunha foram os substratos que demonstraram maior capacidade de produ??o das enzimas amilol?ticas, sendo os coprodutos selecionados para a etapa de otimiza??o da produ??o das enzimas. Diferentes condi??es de processo foram otimizadas com intuito de obter o m?ximo rendimento da produ??o de amilases, atrav?s do emprego de delineamentos experimentais aplicados ? Metodologia de Superf?cie de Resposta. Os processos fermentativos deste trabalho foram realizados ? temperatura de 37?C, 120 rpm de agita??o, utilizando solu??o de sais para suplementa??o do meio. As vari?veis pH, raz?o s?lido-l?quido (S/L) (% m/v) e concentra??o de NH4NO3 (gL-1) foram estudadas. As dosagens das atividades enzim?ticas foram realizadas em tempos de fermenta??o de 12, 24, 36, 48 e 72 horas. A m?xima produ??o das amilases foi alcan?ada com 24 horas de fermenta??o, S/L de 12% e pH 7,0, obtendo valores de 3.393 U.mL-1 com a farinha de pupunha e 196 U.mL-1 com a torta de maca?ba como substratos. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Qu?mica, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2012. / ABSTRACT Amylases are enzymes that act in the rupture of glycosidic bonds present in the chains of amylose and amylopectin. Amylases have applications in diverse areas such as pulp and paper industry, textiles, laundry detergents and cleaning products, chemical and pharmaceutical industry, production of vitamins and antibiotics. Although the amylases are found in plants, animals and micro-organisms, microbial enzymes generally meet satisfactorily the industrial demand. The microbial enzymes can be obtained by fermentative procedures, which may be obtained by cultivation both surface and submerged cultivation of micro-organisms. This study aimed to evaluate the production of amylolytic enzymes by submerged fermentation using Bacillus amyloliquefaciens ATCC 23350, and co-products from biodiesel production chain as substrates. The capacity of the production of amylolytic enzymes was tested using different substrates such as co-products, these being: macauba cake, palm kernel cake, peach palm flour, castor bean and lupine cake. The peach palm flour and macauba cake were the substrates which show greater production capacity of amylolytic enzymes, and co-products selected for the optimization step of enzyme production. Different process conditions were optimized with the aim of obtaining the maximum yield of amylases, through the use of experimental designs applied to the Response Surface Methodology. The fermentation process of this work was performed at 37?C, 120 rpm agitation, using salt solution for supplementation of the medium. The pH, liquid-solid ratio (S/L) (% w/v) and concentration of NH4NO3 (gl-1) were studied. The measurements of enzyme activities were carried out in fermentation times of 12, 24, 36, 48 and 72 hours. Maximum production of amylase was achieved with 24 hours of fermentation, S/L of 12% and pH 7.0 to obtain values of 3.393 U.mL-1 with peach palm flour and 196 U.mL-1 with maca?ba cake as substrate.
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Avalia??o da torta de dend? (Elaeis guineensis) para produ??o de bioetanol de segunda gera??o / Evaluation of palm cake (Elaeis guineensis) for production of second generation ethanol

Ferreira, Crisley Mara de Azevedo 22 February 2013 (has links)
Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-19T13:03:28Z No. of bitstreams: 5 crisley.pdf: 2081607 bytes, checksum: 90ca0fb9cd507118e713cc82f093637a (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2110 bytes, checksum: b4c884761e4c6c296ab2179d378436d4 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-20T09:27:10Z (GMT) No. of bitstreams: 5 crisley.pdf: 2081607 bytes, checksum: 90ca0fb9cd507118e713cc82f093637a (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2110 bytes, checksum: b4c884761e4c6c296ab2179d378436d4 (MD5) / Made available in DSpace on 2015-02-20T09:27:10Z (GMT). No. of bitstreams: 5 crisley.pdf: 2081607 bytes, checksum: 90ca0fb9cd507118e713cc82f093637a (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2110 bytes, checksum: b4c884761e4c6c296ab2179d378436d4 (MD5) Previous issue date: 2013-12-17 / A busca por energias alternativas, sustent?veis e economicamente vi?veis, colocou em destaque o uso dos biocombust?veis. Os estudos recentes apontam o uso de biomassas residuais como candidatas potenciais para produ??o de bioenergia. Nesse contexto, a presente disserta??o teve por objetivo ava-liar a torta de dend? como insumo para produ??o de etanol de segunda gera??o por meio de estudos que envolveram etapas de pr?-tratamento ?cido e alcalino, sacarifica??o e fermenta??o. Inicialmente foi determinada a composi??o centesimal da torta de dend?, indicando a presen?a de 53,2% de car-boidratos totais, dos quais 32% referente a fra??o de celulose. Para otimiza??o do pr?-tratamento ?cido foi aplicado um Planejamento Fatorial atrav?s de delineamento composto central rotacional. O programa STATISTICA Vers?o 8.0 (Statsoft Inc., Tulsa,) foi utilizado para an?lise dos dados. O pr?-tratamento com ?cido sulf?rico dilu?do resultou na remo??o de pelo menos 82% da hemicelulose presente na torta de dend?. O pr?-tratamento alcalino subsequente foi capaz de remover pelo menos 72% da lignina da biomassa, um interferente do processo fermentativo. Na sequ?ncia o processo de sacarifica??o foi otimizado com o uso de delineamento composto central rotacional com 3 fatores, 4 pontos centrais e 6 pontos axiais, onde foram avaliadas a concentra??o de celulases, a raz?o s?lido-l?quido e o tempo. O hidrolisado enzim?tico obtido em condi??o otimizada, com 80% de convers?o da celulose a a??cares redutores, foi submetido ? fermenta??o com Saccharomyces cerevisiae apre-sentando um YP/S de 0,49 com 5,4%(v/v) de ?lcool no mosto fermentado. Os dados obtidos indicaram que a torta de dend? avaliada apresenta elevado potencial para produ??o de bioetanol de segunda gera??o. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Qu?mica, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2013. / ABSTRACT The search for alternative energies, sustainable and economically viable, highlighted the use of biofuels. Recent studies indicate the use of residual biomass as potential candidates for bioenergy production. In this context, the present dissertation aimed at evaluating the palm cake as a feedstock for the production of second generation ethanol through studies involving acid and alkaline pretreatment steps, saccharification and fermentation. Initially it was determined the chemical composition of palm cake, indicating the presence of 53.2% of total carbohydrates, of which 32% related to cellulose. To optimize the pretreatment was applied a Factorial Design by central composite rotational design. The program STATISTICA version 8.0 (Statsoft Inc., Tulsa,) was used for data analysis. Pretreatment with dilute sulfuric acid resulted in the removal of at least 82% of the hemicellulose present in palm cake. The subsequent alkaline pretreatment was able to remove at least 72% of the lignin from the biomass, an interfering of fermentation. Further the saccharification process was optimized by the use of central composite design with three factors, fourth central points and six axial points, evaluating the concentration of cellulase, the solid-liquid ratio and the time. The enzymatic hydrolyzate obtained under optimized conditions with 80% conversion of cellulose to sugars was subjected to fermentation with Saccharomyces cerevisiae showing an YP/S of 0.49 based on 5.4% (v/v) of alcohol in the fermented must. The data indicated that the palm kernel cake evaluated presents high potential for production of second generation bioethanol.
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Desenvolvimento e aplica??o do material comp?sito HRP/PANI/PEG-MWCNT como plataforma para detec??o de per?xido de hidrog?nio a baixo potencial / Development and application of HRP/PANI/PEG-MWCNT composite material as a platform for hydrogen peroxide detection with high sensitivity at low potential

Silva, Jussara Vieira da 26 February 2013 (has links)
Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-19T13:34:44Z No. of bitstreams: 5 jus.pdf: 3394180 bytes, checksum: 71d0ff7761a41fcaa36b37cfba79f687 (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2110 bytes, checksum: b4c884761e4c6c296ab2179d378436d4 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-20T10:26:30Z (GMT) No. of bitstreams: 5 jus.pdf: 3394180 bytes, checksum: 71d0ff7761a41fcaa36b37cfba79f687 (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2110 bytes, checksum: b4c884761e4c6c296ab2179d378436d4 (MD5) / Made available in DSpace on 2015-02-20T10:26:30Z (GMT). No. of bitstreams: 5 jus.pdf: 3394180 bytes, checksum: 71d0ff7761a41fcaa36b37cfba79f687 (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2110 bytes, checksum: b4c884761e4c6c296ab2179d378436d4 (MD5) Previous issue date: 2013-12-17 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (Capes) / Atualmente os nanotubos de carbono (NTC) representam um importante grupo de nanomateriais com atrativas propriedades qu?micas, eletr?nicas e mec?nicas. Estes materiais podem ser combinados a pol?meros, de maneira a moldar as propriedades f?sicas desses compostos (nanotubos-pol?mero), aumentando sua condutividade el?trica, estabilidade qu?mica e resist?ncia mec?nica. O presente trabalho apresenta o desenvolvimentoum material comp?sitonanoestruturado ? base de polianilina (PANI) e nanotubos de carbono de paredes m?ltiplas(MWCNT), para tal, os NTC foram funcionalizados com agrupamentos amina (PEG-NH2). A inser??o do grupamento amina junto aos NTC (PEG-MWCNT) foi confirmada atrav?s da caracteriza??o deste material utilizando as t?cnicas de Microscopia Eletr?nica de Varredura (MEV), Espectroscopia de infravermelho com transformada de fourrier(FT-IR) e Espectroscopia de Energia dispersiva de Raios-X. Foi produzido um eletrodo modificado atrav?s da polimeriza??o do mon?mero anilinaem presen?a dos NTC funcionalizados denominado PANI/PEG-MWCNT. Foram analisadas as propriedades do comp?sito PANI/PEG-MWCNT pelas t?cnicas de Voltametria c?clica e Espectroscopia de Imped?ncia Eletroqu?mica, atrav?s das quais foi verificado que a presen?a combinada dos NTC e da PANI favorece forma??o de um material comp?sito com propriedades sin?rgicas. Al?m disso, atrav?s da Microbalan?a Eletroqu?mica de Cristal de Quartzo pode-se constatarque a dopagem da PANI com PEG-MWCNT favorece o transporte de pr?tons significativamente. Atrav?s da t?cnica de microscopia eletroqu?mica de varredura foi poss?vel evidenciar que existem mais s?tios ativos na superf?cie do filme de PANI/PEG-MWCNT do que na superf?cie da PANI devido ? incorpora??o uniforme dos MWCNT. Finalmente, o eletrodo modificado com o material comp?sito foi utilizado como plataforma no desenvolvimento de um biossensor enzim?tico, pela imobiliza??o da enzima HRP (HRP/PANI/PEG-MWCNT). O biossensor HRP/PANI/PEG-MWCNT apresentou um ?timo suporte para aredu??o de per?xido de hidrog?nio a baixo potencial (-100 mV) vs Ag/AgCl, bem como alta sensibilidade (1.01) ?Acm-2 ?M?1e baixo limite de detec??o de 0,5 ?M L-1. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Qu?mica, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2013. / ABSTRACT Currently carbon nanotubes (NTC) represent an important group of nanomaterials with attractive properties (chemical, electronic and mechanical). These materials can be combined with polymers in order to shape their physical properties of these compounds (nanotube-polymer), increasing its electrical conductivity, chemical stability and mechanical strength. In fact, this study shows the production of a nanostructured composite material based on polyaniline (PANI) and carbon nanotubes multi-walled (MWCNT), for this, the NTC were functionalized with amine groups (PEG-NH2). The insertion of the amine grouping together to NTC (MWCNT-PEG) was confirmed by the characterization of this material using the techniques of Scanning Electron Microscopy (SEM) spectroscopy, Fourier transform infrared (FT-IR) spectroscopy and energy dispersive X-Ray. A modified electrode was produced through polymerization in the presence of PANI called NTC functionalized PANI/PEG-MWCNT. The properties of the composite PANI/MWCNT-PEG were examined by cyclic voltammetry and Electrochemical Impedance Spectroscopy, it was found that the combined presence of the NTC and polyaniline in the modified electrode provides a formation of a composite material with synergistic properties. Furthermore, through the technique of Electrochemical Microbalance Quartz Crystal can be seen that doping of PANI with PEG-MWCNT facilitates significantly the transport of protons. Finally, through the technique of scanning electrochemical microscopy was possible to show that there are more active sites on the surface of the film of PANI / MWCNT-PEG than on the surface of PANI due to the incorporation of MWCNT uniform. Lastly, the modified electrode composite material was used as a support for a biosensor for immobilization of the enzyme HRP (HRP/PANI/PEG-MWCNT). The biosensor HRP/PANI/MWCNT-PEG showed a great support for the reduction of hydrogen peroxide at a low potential (-100mv) vs Ag / AgCl as well as high sensitivity (1.01) ?A cm-2 mM-1 and low detection limit 0.5 ?m.
79

Produ??o de enzimas celulol?ticas e xilanol?ticas por fungos filamentosos utilizando res?duos da cadeia do biodiesel como fonte de carbono / Production of cellulolytic and xylanolytic enzymes by filamentous fungi utilizing wastes from biodiesel production chain as carbon source

Santos, Ricardo Salviano dos 11 December 2012 (has links)
Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-19T13:34:44Z No. of bitstreams: 5 ric.pdf: 5207435 bytes, checksum: f03a11b8bcdc89eef456751ccb1f74f2 (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2110 bytes, checksum: b4c884761e4c6c296ab2179d378436d4 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-20T10:28:40Z (GMT) No. of bitstreams: 5 ric.pdf: 5207435 bytes, checksum: f03a11b8bcdc89eef456751ccb1f74f2 (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2110 bytes, checksum: b4c884761e4c6c296ab2179d378436d4 (MD5) / Made available in DSpace on 2015-02-20T10:28:40Z (GMT). No. of bitstreams: 5 ric.pdf: 5207435 bytes, checksum: f03a11b8bcdc89eef456751ccb1f74f2 (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2110 bytes, checksum: b4c884761e4c6c296ab2179d378436d4 (MD5) Previous issue date: 2013-09-20 / A pesquisa b?sica e aplicada voltada para o conhecimento e produ??o de celulases e xilanases microbianas constituem-se em valorosa a??o para o desenvolvimento de produtos e processos biotecnol?gicos. Estas enzimas t?m sido utilizadas na ind?stria de alimentos, cervejarias, vin?colas, produ??o de ra??o, ind?stria t?xtil e fabrica??o de papel. A demanda por tais catalisadores tem crescido rapidamente, encorajada principalmente pela ind?stria de biocombust?veis, em especial para a produ??o de etanol de 2? Gera??o. Neste contexto, o objetivo deste trabalho foi produzir enzimas celulol?ticas e xilanol?ticas com o uso de fungos filamentosos de ocorr?ncia natural, utilizando res?duos s?lidos da cadeia produtiva do biodiesel como fontes de carbono. Tr?s linhagens de fungos filamentosos isoladas de amostras ambientais foram avaliadas para produ??o de celulases e xilanases. Como par?metro de compara??o, utilizou-se o Trichoderma reesei CCT2768, linhagem conhecida como produtora de celulases. Dentre as linhagens avaliadas, um isolado denominado Aspergillus sp AN1257 foi o que se destacou para a produ??o de enzimas celulol?ticas e xilanol?ticas, superando inclusive a produ??o de celulases por T. reesei nas mesmas condi??es fermentativas. A fonte de carbono que melhor induziu a produ??o das enzimas investigadas pelo Aspergillus sp AN1257 foi a torta de caro?o de algod?o. Em busca da condi??o ?tima para a produ??o das enzimas estudadas foi realizado um planejamento fatorial e posteriormente aplicado um delineamento composto central rotacional (DCCR). Ap?s a aplica??o das condi??es ?timas para a produ??o enzim?tica desejada, o extrato obtido apresentou valores de 3,12 U/mL para atividade endoglucan?sica e 76,4 U/mL para a atividade xilan?sica. O extrato enzim?tico produzido apresentou atividade promissora quando utilizado na hidr?lise de lignocelulose em alguns res?duos agroindustriais. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Qu?mica, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2012. / ABSTRACT The basic and applied research focused on the knowledge and production of microbial cellulases and xylanases constitute a valuable action for the development of biotechnology products and processes. These enzymes have been used in the food industry, breweries, wineries, feed production, textile and paper manufacturing. The demand for such catalysts has grown rapidly, encouraged mainly by the biofuels industry, in particular for the production of 2nd Generation ethanol. In this context, the aim of this work was to produce cellulolytic and xylanolytic enzymes using naturally occurring filamentous fungi and solid waste of the biodiesel productive chain as carbon source. Three strains of filamentous fungi isolated from ambient samples have been evaluated for production of cellulases and xylanases. As reference microbial strain, it was used Trichoderma reesei CCT2768, known a good producer of cellulases. Among the strains tested, an isolated named Aspergillus sp AN1257 stood out for the production of cellulolytic and xylanolytic activity, surpassing even the production of cellulases by T. reesei under the same fermentation conditions. The carbon source which better induced the production of the investigated enzymes by Aspergillus sp AN1257 was cottonseed cake. In search of the optimum condition for the production of the investigated enzymes it was performed a factorial design and then it was applied a rotational central composite design (RCCD). After application of optimal condiction for enzyme production, the extract obtained showed values ??of 3.12 U/mL for endoglucanasic activity and 76.4 U/mL for xylanolytic activity. The enzyme extract produced showed promising application when used in the hydrolysis of lignocellulose in some agro-industrial residues.
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Res?duos de agrot?xicos em morangos e influ?ncia de filmes biodegrad?veis na qualidade dos frutos no armazenamento p?s-colheita / Pesticide residues in strawberries and influence of biodegradable films on fruit quality in post-harvest storage.2012.143p. Master`s Dissertation (StrictuSensuGraduate Program in Chemistry)

Guedes, Tiago de Jesus 06 December 2012 (has links)
Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-19T13:34:44Z No. of bitstreams: 5 tia.pdf: 1423954 bytes, checksum: 51545efc1d46e2caf827b6b93408510c (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2110 bytes, checksum: b4c884761e4c6c296ab2179d378436d4 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-20T10:30:56Z (GMT) No. of bitstreams: 5 tia.pdf: 1423954 bytes, checksum: 51545efc1d46e2caf827b6b93408510c (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2110 bytes, checksum: b4c884761e4c6c296ab2179d378436d4 (MD5) / Made available in DSpace on 2015-02-20T10:30:56Z (GMT). No. of bitstreams: 5 tia.pdf: 1423954 bytes, checksum: 51545efc1d46e2caf827b6b93408510c (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2110 bytes, checksum: b4c884761e4c6c296ab2179d378436d4 (MD5) Previous issue date: 2013-09-20 / Morangos s?o frutos altamente apreciados pelos consumidores, pelas suas caracter?sticas sensoriais e nutricionais e por promoverem benef?cios ? sa?de humana. No entanto, durante a fase de cultivo, o uso indiscriminado de agrot?xicos na cultura pode tornar os frutos impr?prios para o consumo. Al?m disso, s?o necess?rias ado??o de medidas para prolongar o tempo de vida ?til dos frutos ap?s a colheita. Visando caracterizar a qualidade dos frutos comercializados em Diamantina e tamb?m propor t?cnicas para melhor conserva??o dos morangos no armazenamento p?s-colheita realizou-se este trabalho, que constou de dois experimentos. No primeiro procurou-se identificar e quantificar res?duos dos agrot?xicos nos frutos os quais foram coletados em sete fazendas da regi?o em tr?s ?pocas diferentes. A extra??o dos agrot?xicos da matriz foi realizada por extra??o s?lido-l?quido com parti??o em baixa temperatura (ESL-PBT) e a detec??o e quantifica??o foram feitas por cromatografia gasosa com detector de captura de el?trons. Em 28,57% das amostras n?o foram detectados res?duos dos agrot?xicos azoxistrobina, bifentrina, cipermetrina, clorotalonil, clorpirof?s, difenoconazol, endossulfam, iprodiona, ?-cialotrina e permetrina. Em 33,33% dessas amostras constataram-se res?duos abaixo do limite m?ximo de res?duos (LMR) estabelecido e em 38,10% os n?veis desses res?duos nas amostras foram considerados insatisfat?rios por apresentarem res?duos de produtos n?o autorizados e/ou se autorizados acima do LMR. No segundo experimento avaliou-se o efeito de revestimento de amostras de morango com coberturas comest?veis ? base de amido previamente extra?do de banana verde, quitosana e cloreto de c?lcio no armazenamento refrigerado. Os frutos foram coletados no munic?pio de Datas, MG e submetidos aos seguintes tratamentos: imers?o em solu??es de quitosana (QTS), CaCl2 (Ca), amido de banana (Am), amido e quitosana (AmQTS), quitosana e CaCl2 (QTSCa) , amido e CaCl2 (AmCa), amido, quitosana e CaCl2 (AmQTSCa), al?m do grupo controle (Cte). No tempo inicial e ap?s 3, 6, 9, 12 e 16 dias do in?cio do armazenamento, os frutos submetidos aos diferentes tipos de revestimento sob refrigera??o foram avaliados quanto a perda de mat?ria fresca (%), pH, s?lidos sol?veis (?Brix), acidez titul?vel (em percentual e percentual de ?cido c?trico), teor de vitamina C (mg 100 g-1), compostos fen?licos (g 100 g-1 de ?cido t?nico), flavon?ides (g 100 g-1 de ?cido t?nico), antocianinas (mg 100 g-1), atividade antioxidante total (?M sulfato ferroso g-1 de fruta) e a??cares (g 100 g-1). Foram tamb?m avaliados desenvolvimento de bolores e leveduras e coliformes totais ao longo do armazenamento. Frutos que n?o receberam o revestimento mantiveram suas propriedades f?sico-qu?micas por 11 dias. Ap?s este per?odo de armazenamento houve perdas na qualidade dos frutos. Por outro lado frutos submetidos aos tratamentos quitosana, quitosana-CaCl2 e amido de banana-quitosana-CaCl2 mantiveram suas propriedades f?sico-qu?micas durante o per?odo avaliado (16 dias). Os revestimentos com quitosana mostraram-se, ainda, eficientes na prote??o de crescimento de micro-organismos. Concluiu-se que ? necess?rio conscientizar os produtores e os agentes de fiscaliza??o na utiliza??o sobre o uso inadequado dos agrot?xicos e que no caso do armazenamento dos frutos o envolvimento destes com filmes de quitosana prolongam as suas qualidades nutricionais al?m dificultar o ataque de fungos. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Qu?mica, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2012. / ABSTRACT Strawberries fruits are highly appreciated by consumers for their sensory and nutritional characteristics and for promoting benefits to human health. However, during its cultivation, indiscriminate use of pesticides in crop can make the fruits unfit for consumption. Besides, it is necessary the adoption of measures to prolong the life of the fruits after harvest. In order to characterize the quality of the fruit sold in Diamantina, Brazil, and also to propose techniques to improve the conservation of strawberries in post-harvest storage this work was conducted, and carried out in two experiments. In the first, we tried to identify and to quantify pesticide residues in fruits which were collected in seven farms in the region in three different eras. The extraction of pesticides was performed by solid-liquid matrix extraction with partition under low temperature (SLE-LTP) and the detection and quantification were performed by gas chromatography with electron capture detector. In 28.57% of the samples were not detected residues of pesticides azoxystrobin, bifenthrin, cypermethrin, chlorothalonil, chlorpyrifos, difenoconazole, endosulfan, iprodione, ?-cyhalothrin and permethrin. In 33.33% of these samples, there have been noticed residues below the maximum residue limit (MRL) established and in 38.10% of the samples, have been found levels of unauthorized products and / or above MRL. The second experiment evaluated the effect of coating samples of strawberry with previously edible coatings based on starch on extracted from green banana, chitosan and calcium chloride in cold storage. The fruits were collected in the municipality of Datas, MG and subjected to the following treatments: immersion in solutions of chitosan (CTS), CaCl2 (Ca), banana starch (Am), starch and chitosan (AmQTS), chitosan and CaCl2 (QTSCa), starch and CaCl2 (AmCa), starch, chitosan and CaCl2 (AmQTSCa), and the control group (Cte). At baseline and after 3, 6, 9, 12 and 16 days from the beginning of storage, the fruits subjected to different types of coating under refrigeration were assessed for fresh weight loss (%), pH, soluble solids (?Brix), titratable acidity (in percentage and percentage of citric acid), vitamin C (mg 100 g-1), phenolic compounds (g 100 g-1 of tannic acid), flavonoids (g 100 g-1 of tannic acid), anthocyanins (mg 100 g-1), total antioxidant activity (?M ferrous sulphate g-1 fruit) and sugars (g 100 g-1). We also evaluated the development of molds, yeasts and coliforms during storage. Fruits that have not received the coating maintained its physicochemical properties for 11 days. After this storage period there have been losses in fruit quality. Besides, fruits treated with chitosan, chitosan-CaCl2 and banana starch-chitosan-CaCl2 maintained their physicochemical properties during the study period (16 days). The chitosan coating proved also to be effective in protecting the growth of micro-organisms. It was concluded that it is necessary to educate producers and control staff about the inappropriate use of pesticides, and that in the case of storage of fruits their involvement with chitosan films extend its nutritional qualities and protect them against fungal attack.

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