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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

Avaliação da produção biotecnológica de 2-feniletanol em resíduo líquido de fecularia

Oliveira, Simone Maria Menegatti de 07 July 2010 (has links)
Made available in DSpace on 2017-07-10T19:24:47Z (GMT). No. of bitstreams: 1 Simone Maria Menegatti de Oliveira.pdf: 745176 bytes, checksum: 3a5240485b0941a0c7d894af6e3b5ade (MD5) Previous issue date: 2010-07-07 / 2-phenylethanol is the most used fragrance in the food, cosmetics and fragrance industry. It is mainly produced by chemical process, but with many impurities. The biotechnological process of production is feasible and is being studied with various microrganisms, among them, Geotrichum fragrans, Saccharomyces cerevisiae and Kluyveromyces marxianus. The use of cassava wastewater as substrate in this process makes it less expensive and reduce environmental pollution caused by it. The objective or this work was to evaluate the production of 2-phenylethanol in the cultivation of Geotrichum fragrans, Saccharomyces cerevisiae and Kluyveromyces marxianus in cassava wastewater, analyzing the effect of two carbon sources on production of the aroma, besides increasing the production of 2 - phenylethanol to the greater efficiency of conversion carbon source/2-feniletanol, varying concentrations of carbon source and phenylalanine at cassava wastewater. For this, the three microrganisms mentioned were cultured in 50mL cassava wastewater plus 50g.L-1 of glucose and 3g.L-1 of L-phenylalanine in sterile Erlenmeyer flasks, on shaker at 150 rpm, 24 ° C for 120 hours, to check the time of peak production of 2-phenylethanol and what microrganism largest producer. It was then checked the production of aroma with 50g.L-1 of glucose and fructose, while maintaining the same amount of L-phenylalanine. And finally, by fatorial design, were tested concentrations of glucose and L-phenylalanine, in order to obtain higher yield and bioconversion of 2-phenylethanol. The experimental model was validated. It was analyzed in the pH, COD, reducing sugars, L-phenylalanine and 2-phenylethanol. In the precipitate was quantified indirectly as biomass, the Volatile Suspended Solids. The results showed that S. cerevisiae was the best producer of 2-phenylethanol in the effluent of cassava starch, obtaining 0.74 g.L-1, followed by K. marxianus, with 0.19 g.L-1 and finally by G. fragrans with 0.08 g.L-1. Glucose was the best carbon source for obtention of 2- phenylethanol for S. cerevisiae and K. marxianus. There was no significant difference between the production of 2-phenylethanol using glucose or fructose for G. fragrans. The best combination of glucose and L-phenylalanine for production of 2-phenylethanol, was 20,0 and 5.5 g.L-1 respectively, obtaining production of 1.33 g.L-1of aroma in the validation. / O 2-feniletanol é a fragrância mais utilizada na indústria de alimentos, cosmética e de perfumes. É produzido principalmente por processo químico, porém com muitas impurezas. O processo biotecnológico de produção é viável e está sendo estudado com vários microrganismos, entre eles, o Geotrichum fragrans (GF), Saccharomyces cerevisiae (SC) e Kluyveromyces marxianus (KM). O uso de resíduo líquido de fecularia como substrato neste processo torna-o menos dispendioso, além de reduzir a poluição ambiental causada pelo mesmo. O objetivo deste trabalho foi avaliar a produção de 2-feniletanol no cultivo de GF, SC e KM em resíduo líquido de fecularia, analisando o efeito de duas fontes de carbono na produção do aroma, além de aumentar a produção de 2-feniletanol até a maior eficácia de conversão fonte de carbono/2-feniletanol, variando as concentrações da fonte de carbono e de fenilalanina no resíduo líquido de fecularia. Para isso, os três microrganismos citados foram cultivados em 50 ml de resíduo líquido de fecularia, acrescidos de 50 g.L-1 de glicose e 3 g.L-1 de L-fenilalanina, em frascos erlenmeyers estéreis, em agitador a 150 rpm, 24 ºC, por 120 h, para verificar o tempo de maior produção de 2-feniletanol e qual microrganismo maior produtor. Foi então verificada a produção de aroma com 50g.L-1 de glicose e frutose, mantendo a mesma quantidade de L-fenilalanina. E finalmente, através de planejamento fatorial, foram testadas concentrações de glicose e L-fenilalanina, a fim de se obter maior produção e bioconversão de 2-feniletanol. O modelo experimental foi validado. Analisou-se o pH, a DQO, os açúcares redutores, a L-fenilalanina e o 2-feniletanol. No precipitado foi quantificada a biomassa indiretamente como sólidos suspensos voláteis. Os resultados obtidos demonstraram que SC foi o melhor produtor de 2-feniletanol em água residual de fecularia de mandioca, obtendo 0,74 g.L-1, seguido pelo K. marxianus, com 0,19 g.L-1 e por último pelo G. fragrans, com 0,08 g.L-1. A glicose foi a melhor fonte de carbono para obtenção do 2-feniletanol para S. cerevisiae e K. marxianus. Não houve diferença significativa entre a produção de 2-feniletanol utilizando glicose ou frutose para o G. fragrans. A melhor conjugação dos níveis de glicose e L-fenilalanina para produção de 2- feniletanol foi de 20,0 e 5,5 g.L-1 respectivamente, obtendo produção de 1,33 g.L-1do aroma na validação.
2

Avaliação da produção biotecnológica de 2-feniletanol em resíduo líquido de fecularia

Oliveira, Simone Maria Menegatti de 07 July 2010 (has links)
Made available in DSpace on 2017-05-12T14:48:11Z (GMT). No. of bitstreams: 1 Simone Maria Menegatti de Oliveira.pdf: 745176 bytes, checksum: 3a5240485b0941a0c7d894af6e3b5ade (MD5) Previous issue date: 2010-07-07 / 2-phenylethanol is the most used fragrance in the food, cosmetics and fragrance industry. It is mainly produced by chemical process, but with many impurities. The biotechnological process of production is feasible and is being studied with various microrganisms, among them, Geotrichum fragrans, Saccharomyces cerevisiae and Kluyveromyces marxianus. The use of cassava wastewater as substrate in this process makes it less expensive and reduce environmental pollution caused by it. The objective or this work was to evaluate the production of 2-phenylethanol in the cultivation of Geotrichum fragrans, Saccharomyces cerevisiae and Kluyveromyces marxianus in cassava wastewater, analyzing the effect of two carbon sources on production of the aroma, besides increasing the production of 2 - phenylethanol to the greater efficiency of conversion carbon source/2-feniletanol, varying concentrations of carbon source and phenylalanine at cassava wastewater. For this, the three microrganisms mentioned were cultured in 50mL cassava wastewater plus 50g.L-1 of glucose and 3g.L-1 of L-phenylalanine in sterile Erlenmeyer flasks, on shaker at 150 rpm, 24 ° C for 120 hours, to check the time of peak production of 2-phenylethanol and what microrganism largest producer. It was then checked the production of aroma with 50g.L-1 of glucose and fructose, while maintaining the same amount of L-phenylalanine. And finally, by fatorial design, were tested concentrations of glucose and L-phenylalanine, in order to obtain higher yield and bioconversion of 2-phenylethanol. The experimental model was validated. It was analyzed in the pH, COD, reducing sugars, L-phenylalanine and 2-phenylethanol. In the precipitate was quantified indirectly as biomass, the Volatile Suspended Solids. The results showed that S. cerevisiae was the best producer of 2-phenylethanol in the effluent of cassava starch, obtaining 0.74 g.L-1, followed by K. marxianus, with 0.19 g.L-1 and finally by G. fragrans with 0.08 g.L-1. Glucose was the best carbon source for obtention of 2- phenylethanol for S. cerevisiae and K. marxianus. There was no significant difference between the production of 2-phenylethanol using glucose or fructose for G. fragrans. The best combination of glucose and L-phenylalanine for production of 2-phenylethanol, was 20,0 and 5.5 g.L-1 respectively, obtaining production of 1.33 g.L-1of aroma in the validation. / O 2-feniletanol é a fragrância mais utilizada na indústria de alimentos, cosmética e de perfumes. É produzido principalmente por processo químico, porém com muitas impurezas. O processo biotecnológico de produção é viável e está sendo estudado com vários microrganismos, entre eles, o Geotrichum fragrans (GF), Saccharomyces cerevisiae (SC) e Kluyveromyces marxianus (KM). O uso de resíduo líquido de fecularia como substrato neste processo torna-o menos dispendioso, além de reduzir a poluição ambiental causada pelo mesmo. O objetivo deste trabalho foi avaliar a produção de 2-feniletanol no cultivo de GF, SC e KM em resíduo líquido de fecularia, analisando o efeito de duas fontes de carbono na produção do aroma, além de aumentar a produção de 2-feniletanol até a maior eficácia de conversão fonte de carbono/2-feniletanol, variando as concentrações da fonte de carbono e de fenilalanina no resíduo líquido de fecularia. Para isso, os três microrganismos citados foram cultivados em 50 ml de resíduo líquido de fecularia, acrescidos de 50 g.L-1 de glicose e 3 g.L-1 de L-fenilalanina, em frascos erlenmeyers estéreis, em agitador a 150 rpm, 24 ºC, por 120 h, para verificar o tempo de maior produção de 2-feniletanol e qual microrganismo maior produtor. Foi então verificada a produção de aroma com 50g.L-1 de glicose e frutose, mantendo a mesma quantidade de L-fenilalanina. E finalmente, através de planejamento fatorial, foram testadas concentrações de glicose e L-fenilalanina, a fim de se obter maior produção e bioconversão de 2-feniletanol. O modelo experimental foi validado. Analisou-se o pH, a DQO, os açúcares redutores, a L-fenilalanina e o 2-feniletanol. No precipitado foi quantificada a biomassa indiretamente como sólidos suspensos voláteis. Os resultados obtidos demonstraram que SC foi o melhor produtor de 2-feniletanol em água residual de fecularia de mandioca, obtendo 0,74 g.L-1, seguido pelo K. marxianus, com 0,19 g.L-1 e por último pelo G. fragrans, com 0,08 g.L-1. A glicose foi a melhor fonte de carbono para obtenção do 2-feniletanol para S. cerevisiae e K. marxianus. Não houve diferença significativa entre a produção de 2-feniletanol utilizando glicose ou frutose para o G. fragrans. A melhor conjugação dos níveis de glicose e L-fenilalanina para produção de 2- feniletanol foi de 20,0 e 5,5 g.L-1 respectivamente, obtendo produção de 1,33 g.L-1do aroma na validação.
3

Pheromone production in the butterfly Pieris napi L

Murtazina, Rushana January 2014 (has links)
Aphrodisiac and anti-aphrodisiac pheromone production and composition in the green-veined white butterfly Pieris napi L. were investigated. Aphrodisiac pheromone biosynthesis had different time constraints in butterflies from the diapausing and directly developing generations. Effects of stable isotope incorporation in adult butterfly pheromone, in the nectar and flower volatiles of  host plants from labeled substrates were measured by solid phase microextraction and gas chromatography–mass spectrometry. A method to fertilize plants with stable isotopes was developed and found to be an effective method to investigate the transfer of pheromone building blocks from flowering plants to butterflies. The anti-aphrodisiac methyl salicylate was not biosynthesized from phenylalanine in flowers of Alliaria petiolata. Both aphrodisiac and anti-aphrodisiac pheromones in P.napi are produced not only from resources acquired in the larval stage, but also from nutritional resources consumed intheadult stage. Males of P. napi produce the anti-aphrodisiac pheromone from both the essential amino acid L-phenylalanine and from common flower fragrance constituents. / <p>QC 20140311</p>
4

L-phenylalanine preloading reduces the 10B(n,α)7Li dose to the normal brain by inhibiting the uptake of boronophenylalanine in boron neutron capture therapy for brain tumours. / L-フェニルアラニンの前投与はホウ素中性子捕捉療法に用いるボロノフェニルアラニンの正常脳の取り込みを抑制する

Watanabe, Tsubasa 23 March 2017 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第20227号 / 医博第4186号 / 新制||医||1019(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 増永 慎一郎, 教授 宮本 享, 教授 伊佐 正 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
5

Propriedades estruturais e eletrônicas do cristal L-fenilalanina ácido nítrico e estudo vibracional sob condições extremas de pressão e temperatura / Structural and electronic properties of L-phenylalanine nitric acid and vibrational study under extreme high pressure and temperature

Silva, Katiane Pereira da January 2014 (has links)
SILVA, Katiane Pereira da. Propriedades estruturais e eletrônicas do cristal L-fenilalanina ácido nítrico e estudo vibracional sob condições extremas de pressão e temperatura. 2014. 119 f. Tese (Doutorado em Física) - Programa de Pós-Graduação em Física, Departamento de Física, Centro de Ciências, Universidade Federal do Ceará, Fortaleza, 2014. / Submitted by Edvander Pires (edvanderpires@gmail.com) on 2015-04-10T21:12:54Z No. of bitstreams: 1 2014_tese_kpsilva.pdf: 5357878 bytes, checksum: 251018043a6c9107f6c8d1df9df190fd (MD5) / Approved for entry into archive by Edvander Pires(edvanderpires@gmail.com) on 2015-04-10T21:13:24Z (GMT) No. of bitstreams: 1 2014_tese_kpsilva.pdf: 5357878 bytes, checksum: 251018043a6c9107f6c8d1df9df190fd (MD5) / Made available in DSpace on 2015-04-10T21:13:24Z (GMT). No. of bitstreams: 1 2014_tese_kpsilva.pdf: 5357878 bytes, checksum: 251018043a6c9107f6c8d1df9df190fd (MD5) Previous issue date: 2014 / The L-phenylalanine is an essential amino acid that takes part of several bio chemicals processes related to the production of some human proteins and enzymes. This essential amino acid is converted into the L-tyrosine amino acid by means of the L-phenylalanine hydroxilase. Amino acids are interesting materials for non linear optics (NLO) applications as they contain a proton donor carboxylic acid (COOH) group and a proton acceptor amine (NH2) group. In the present work, a systematic investigation has been carried out on L-phenylalanine nitric acid [C9H11NO2.C9H11NO2+.NO3-] (LPN) single crystal obtained by slow evaporation at room temperature. This work shows studies performed in a pure atomistic way by computation simulation, on the electronic and optical properties, using method of density functional theory. The crystal was characterized by single crystal X-ray diffraction, Fourier Transform infrared (FT-IR) and Fourier Transform Raman (FT-Raman) analysis. The results of the X-ray diffraction data were analyzed by the Rietveld method. Single crystal data refinement of the LPN crystal shows that this compound grows with a monoclinic structure belonging to the P21 space group with two molecules per unit cell. The calculated lattice parameter is in good agreement with the experimental results. The Mulliken and Hirschfield charges show the zwiterrionic state of the LPN crystal in the DFT converged crystals. The band gap of LPN crystal is indirect and its energy is ~3.55 eV. The 2p orbitals are the largest contributors to the density of states, suggesting that the crystal behaves like an n-type wide gap insulator. We have characterized the LPN crystal at room temperature by means of the FT-IR in the spectral range between 400 cm-1 to 4000 cm-1 and by means of FT-Raman in the spectral range between 50 cm-1 to 3500 cm-1. There was no Raman band observed in the spectral interval between 1700 cm-1 to 2700 cm-1. For wavenumber greater than 3100 cm-1, there was no Raman band. In the range between 2850 cm-1and 3100 cm-1, it observed stretching modes associated with C-H and C-H2 units. Finally, single-crystal samples of LPN were studied by Raman spectroscopy in a diamond-anvil cell up to pressures of ~ 8.0 GPa. From the analysis of the results we observed that the crystal undergoes a phase transition at about 0.6 GPa. The transition is accompanied by the disappearance of a phonon in the external mode region of the spectrum and by changes of both the wavenumber of NH3+ rocking and CH2 rocking vibrations. / A L-fenilalanina é um aminoácido essencial que participa de diversos processos bioquímicos relacionados à constituição de diversas proteínas e enzimas do corpo humano. Este aminoácido essencial através da enzima L-fenilalanina hidroxilase, é convertido no aminoácido L-tirosina. Os aminoácidos são materiais interessantes para aplicações ópticas não lineares (ONL) uma vez que contêm um próton doador do grupo carboxílico (COOH) e um próton receptor do grupo amina (NH2). No presente trabalho, uma investigação sistemática foi realizada para o cristal de L-fenilalanina ácido nítrico [C9H11NO2.C9H11NO2+.NO3-] (LFN) obtido pelo método de evaporação lenta à temperatura ambiente. Neste trabalho, estudamos de forma inteiramente atomística através de simulação computacional as propriedades eletrônicas e ópticas utilizando o método da teoria do funcional da densidade. O cristal foi caracterizado por difração de raios-X, pelas técnicas vibracionais de Transformada de Fourier no infravermelho (FT-IR) e no Raman (FT-Raman). Os resultados de difração de raios-X foram analisados pelo método de Rietveld. Os resultados do refinamento para o cristal LFN mostram que este composto cristaliza-se na estrutura monoclínica pertecente ao grupo especial P21 com duas moléculas por célula unitária. Os parâmetros de rede calculados apresentaram boa concordância com os resultados experimentais. As cargas Mulliken e Hirschfield mostram que o estado zwitteriônico do cristal LFN estão bem convergidas. A energia do gap do cristal LFN (indireto) é aproximadamente 3,55 eV. Os orbitais 2p são os maiores contribuintes para a densidade de estados, o que sugere que o cristal se comporta como um isolante. Apresentamos resultados de caracterização do cristal de LFN à temperatura ambiente, através das técnicas utilizadas de espectroscopia de absorção por transformada de Fourier na região do infravermelho (FT-IR) no intervalo espectral entre 400 cm-1 e 4000 cm-1 e espectroscopia Raman por transformada de Fourier (FT-Raman) no intervalo espectral entre 50 cm-1 e 3500 cm-1. Nenhuma banda Raman foi observada no intervalo espectral entre 1700 cm-1 e 2700 cm-1. Para o intervalo acima de 3100 cm-1 nenhuma banda Raman foi observada, o que garante que o cristal tratado está na forma anidra. Destaca-se, por exemplo, a região entre 2850 cm-1 e 3100 cm-1, onde é esperado serem observados modos vibracionais do tipo estiramento das ligações C-H e do CH2. Finalmente, para o cristal de LFN foram investigados por espectroscopia Raman em uma célula do tipo bigorna de diamantes desde a pressão ambiente até ~ 8,0 GPa. Nas análises dos resultados de altas pressões observamos que o cristal sofre uma transição de fase em torno 0,6 GPa. A transição é acompanhada pelo desaparecimento de um fônon na região dos modos externos do espectro Raman e por alterações das bandas eferentes a vibrações do tipo rocking do NH3+ e CH2.
6

Selenium redox cycling; isolation and characterization of a stimulatory component from tissue of loblolly pine for multiplication of somatic embryos; development of an assay to measure l-phenylalanine concentration in blood plasma

DeSilva, Veronica 25 June 2007 (has links)
Exogenously supplied organoselenium compounds, capable of propagating a selenium redox cycle, were shown to supplement natural cellular defenses against oxidants generated during biological activity. Phenylaminoalkyl selenides were developed in our laboratory as novel substrate analogs for the enzyme dopamine beta-monooxygenase. Recently, phenylaminoalkyl selenides were found to protect plasmid DNA and Molecular beacons from oxoperoxynitrate – mediated damage by scavenging this oxidant and forming the corresponding selenoxides as the sole selenium – containing products. Rate constants were determined for the reactions of the phenylaminoalkyl selenoxides with GSH at physiological pH and 25 degrees C. The kinetic data obtained in current and previous research was subsequently used in a MatLab simulation, which showed the feasibility of selenium redox cycling by GSH in the presence of a cellular oxidant, oxoperoxynitrate. Loblolly pine (LP, Pinus taeda) is the primary commercial species in southern forests covering 11.7 million hectares. Somatic embryogenesis (SE) is an effective technique to implement production of high value genotypes of LP. SE is a multi-step process, which includes initiation of somatic embryo (SME) growth from tree tissue, maintenance and multiplication of early stage SMEs and the maturation / germination phase. In this work, we isolated a substance from stage 2 or 3 LP female gametophyte (FG) tissue that stimulates early stage SME growth, and characterized this substance as citric acid on the basis of 1H NMR and mass spectrometry. We then demonstrated that topical application of citric acid to SMEs stimulates embryo colony growth at p = 0.05 for 3 of the 5 genotypes tested. Phenylketonuria (PKU) is an autosomal recessive disorder caused by an impaired conversion of L-phenylalanine (L-Phe) to L-tyrosine (L-Tyr). A novel assay based on enzymatic - colorimetric methodology (ECA) was developed in order to detect elevated concentrations of L-Phe in undeproteinized plasma of PKU patients via continuous spectrophotometric detection. We report here that L-Phe concentrations in undeproteinized plasma measured using our ECA were comparable to those determined on an amino acid analyzer based on Pearson correlation coefficients and a Bland and Altman comparison.
7

Orthogonality and Codon Preference of the Pyrrolysyl-tRNA Synthetase-tRNAPyl pair in Escherichia coli for the Genetic Code Expansion

Odoi, Keturah 2012 May 1900 (has links)
Systematic studies of basal nonsense suppression, orthogonality of tRNAPyl variants, and cross recognition between codons and tRNA anticodons are reported. E. coli displays detectable basal amber and opal suppression but shows a negligible ochre suppression. Although detectable, basal amber suppression is fully inhibited when a pyrrolysyl-tRNA synthetase (PylRS)-tRNAPyl_CUA pair is genetically encoded. trnaPyl_CUA is aminoacylated by an E. coli aminoacyl-tRNA synthetase at a low level, however, this misaminoacylation is fully inhibited when both PylRS and its substrate are present. Besides that it is fully orthogonal in E. coli and can be coupled with PylRS to genetically incorporate a NAA at an ochre codon, tRNAPyl_UUA is not able to recognize an UAG codon to induce amber suppression. This observation is in direct conflict with the wobble base pair hypothesis and enables using an evolved M. jannaschii tyrosyl-tRNA synthetase-tRNAPyl_UUA pair and the wild type or evolved PylRS-tRNAPyl_UUA pair to genetically incorporate two different NAAs at amber and ochre codons. tRNAPyl_UCA is charged by E. coli tryptophanyl-tRNA synthetase, thus not orthogonal in E. coli. Mutagenic studies of trnaPyl_UCA led to the discovery of its G73U form which shows a higher orthogonality. Mutating trnaPyl_CUA to trnaPyl_UCCU not only leads to the loss of the relative orthogonality of tRNAPyl in E. coli but also abolishes its aminoacylation by PylRS.

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