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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

Caracterização parcial de carboidrases, morfologia do grão de amido e composição centesimal de raízes de maca (Lepidium meyenii Walpers) / Partial characterization of carbohydrases, morphology of starch granules and chemical composition from roots of maca (Lepidium meyenii Walpers)

Sanabria, Gerby Giovanna Rondán 14 December 2005 (has links)
A maca é uma raiz aromática com 52 a 76% de carboidratos e seu período de conservação pós-colheita é bastante longo, sem demonstrar sinais de deterioração. O mecanismo de degradação do amido e dos componentes da parede celular via ação enzimática não eram ainda conhecidos. O objetivo do trabalho foi caracterizar a ação de enzimas amilolíticas e pectinolíticas nessas raízes, bem como a morfologia do grânulo de amido e a composição centesimal. Os resultados mostraram que foi obtida a purificação parcial de β-amilase com peso molecular aproximado de 57 kDa, com atividade máxima a 40,7 ºC e pH de 5,1. A pectinesterase foi extraída a pH 6,0 com maior atividade a 49,4ºC e pH 6,6 a maior atividade da poligalacturonase foi a 46 ºC e pH 5,4, quando extraída a pH 8,5.O teor de amido total foi de 8,92%, os grânulos apresentaram morfologia oval em observados em microscopia eletrônica de varredura (MEV). / Maca is an aromatic root that contends 52 to 76 per cent of carbohydrates and is very stable for a long period without signals of deterioration. The degradation mechanisms of the reserve carbohydrates and the cell wall components by enzymatic way had not been described yet. The main objective of this study was the identification of inner enzymes which degrades the starch and the pectins; the others objectives were the analysis and the morphology of the starch grains as well as the root\'s contend composition. The results showed that was obtained the partial purification of a β- amylase, characterized by the molecular mass of 57 kDa, with a highest activity at 40.7 °C and pH 5.1. The pectinesterease was extracted with a pH of 6.0 and its maximum activity was at 49.4 °C and pH 6.6; the polygalacturonase was extracted with a pH of 8.5 and its top activity was achieved at 46 °C and pH 5.4. The total contend of starch was 8.92 % and the grains had an oval morphology observed by SEM.
2

Mutag?nese cl?ssica e melhoramento do perfil de assimila??o de nitrog?nio para a produ??o de amilase por Talaromyces trachyspermus

Veron, Nahyara Wandscheer 23 September 2016 (has links)
Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2017-04-25T18:49:30Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) nahyara_wandscheer_veron.pdf: 2438141 bytes, checksum: 5dbb316d0dbe26eb1b8b02b31f860c2e (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2017-05-09T17:31:51Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) nahyara_wandscheer_veron.pdf: 2438141 bytes, checksum: 5dbb316d0dbe26eb1b8b02b31f860c2e (MD5) / Made available in DSpace on 2017-05-09T17:31:51Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) nahyara_wandscheer_veron.pdf: 2438141 bytes, checksum: 5dbb316d0dbe26eb1b8b02b31f860c2e (MD5) Previous issue date: 2016 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / As ?-amilases s?o essenciais para a hidr?lise industrial do amido e para a produ??o de etanol a partir de biomassas amil?ceas. Sua obten??o via importa??o impacta negativamente a ind?stria de biocombust?veis no Brasil, de modo que ? preciso impulsionar a produ??o de ?-amilases no mercado interno. Este trabalho teve por objetivo caracterizar e melhorar o perfil de utiliza??o de fontes de nitrog?nio por Talaromyces trachyspermus, um ascomiceto filamentoso, bem como apontar o efeito dessas fontes na produ??o de ?-amilase por processos submersos delineados por planejamento fatorial. Empregando mutag?nese com luz ultravioleta, foram induzidos e selecionados mutantes com perfil para a produ??o de ?-amilase a partir de fontes nitrogenadas mais baratas. A linhagem parental T. trachyspermus T10.5 utilizou todas as fontes de nitrog?nio avaliadas (extrato de levedura, glutamato, glutamina, ureia, sulfato de am?nio e nitrato de s?dio) mas a produ??o de ?-amilase foi inibida nos bioprocessos suplementados com fontes inorg?nicas (sulfato de am?nio e nitrato de s?dio). A an?lise do planejamento fatorial mostrou que extrato de levedura apresentou efeito estat?stico positivo (4,16 ap?s 72 h e 8,93 ap?s 96 h de cultivo) para a produ??o de ?-amilase pela linhagem parental, cuja produ??o atingiu 66,67 ? 0,18 U/mL ap?s 96h em meio suplementado com o n?vel mais elevado de extrato de levedura (3,7 g/L). Um ensaio de gel atividade e eletroforese prot?ica confirmaram a presen?a de uma enzima amilol?tica no filtrado, com peso molecular aproximado de 20 kDa. Dois mutantes foram selecionados: M12 e M15. A an?lise estat?stica apontou um efeito positivo do extrato de levedura (5,05 ap?s 48h e 104,8 ap?s 72 h de cultivo) para a produ??o de ?-amilase pelo mutante M12, que produziu 55,3 ? 0,2 U/mL ap?s 72 h. O mutante M12 produziu ?-amilase com atividade pr?xima ? do parental, mas o m?ximo de produ??o ocorreu 24 h antes. Ambos os mutantes produziram ?-amilase em meio suplementado com fontes inorg?nicas de nitrog?nio, mas a produ??o da linhagem M12 foi mais expressiva: 29,5 ? 0,2 U/mL ap?s 72 h em meio suplementado com sulfato de am?nio. Assim, foram melhorados o perfil de assimila??o de nitrog?nio e a produ??o de amilase a partir de fonte mais econ?mica, bem como foi reduzido o tempo de produ??o. Os resultados permitiram compreender o efeito das fontes de nitrog?nio e de carbono na produ??o de amilase por T. trachyspermus, gerando conhecimentos sobre fisiologia f?ngica, que ser?o posteriormente aplicados para a otimiza??o da produ??o pelas linhagens T10.5 e M12. / Disserta??o (Mestrado) ? Programa de P?s-gradua??o em Biocombust?veis, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2016. / The enzymes ?-amylases are fundamental for the industrial hydrolysis of starch and for ethanol production from amylaceous biomasses. Their acquisition via importation impacts negatively the biofuels industry in Brazil, so that it is necessary to propel ?-amylase production in the internal market. This work aimed to characterize and improve the nitrogen source utilization profile of Talaromyces trachyspermus, a filamentous ascomycete, and to determine the effects of nitrogen sources on ?-amylase production in submerged processes designed by factorial planning. By means of mutagenesis with ultraviolet light, mutants with profile for ?-amylase production from more economical nitrogen sources were induced and selected. The parental strain T. trachyspermus T10.5 used all the nitrogen sources evaluated (yeast extract, glutamate, glutamine, urea, ammonium sulfate and sodium nitrate) but ?-amylase production was inhibited in bioprocesses supplemented with inorganic sources (ammonium sulfate and sodium nitrate). Factorial planning analysis showed that yeast extract exerted a positive statistical effect (4.16 after 72 h and 8.93 after 96 h of cultivation) on ?-amylase production by the parental strain, whose production reached 66.67 ? 0.18 U/mL after 96 h in media supplemented with yeast extract (3.7 g/L). A gel activity assay and protein electrophoresis confirmed the presence of an amylolitic enzyme in the filtrate, with an approximate molecular weight of 20 kDa. Two mutants were selected: M12 and M15. Statistical analysis revealed a positive effect of yeast extract (5.05 after 48 h e 104.8 after 72 h of cultivation) on ?-amylase production by the mutant M12, which produced 55.3 ? 0.2 U/mL after 72 h. Mutant M12 produced a ?-amylase activity similar to that of the parental, but the maximal production was anticipated in 24 h. Both mutants produced ?-amylase in media supplemented with inorganic nitrogen sources, but the production of strain M12 was more meaningful: 29.5 ? 0.2 U/mL after 72 h in medium supplemented with ammonium sulphate. Thus, the nitrogen assimilation profile and amylase production from a more economical source were improved, as well as it was reduced the production time. Results allowed understand nitrogen and carbon sources effect on amylase production by T. trachyspermus, and yielded knowledge about fungal physiology that will be further applied for optimization of production by strains T10.5 and M12.
3

Caracterização parcial de carboidrases, morfologia do grão de amido e composição centesimal de raízes de maca (Lepidium meyenii Walpers) / Partial characterization of carbohydrases, morphology of starch granules and chemical composition from roots of maca (Lepidium meyenii Walpers)

Gerby Giovanna Rondán Sanabria 14 December 2005 (has links)
A maca é uma raiz aromática com 52 a 76% de carboidratos e seu período de conservação pós-colheita é bastante longo, sem demonstrar sinais de deterioração. O mecanismo de degradação do amido e dos componentes da parede celular via ação enzimática não eram ainda conhecidos. O objetivo do trabalho foi caracterizar a ação de enzimas amilolíticas e pectinolíticas nessas raízes, bem como a morfologia do grânulo de amido e a composição centesimal. Os resultados mostraram que foi obtida a purificação parcial de β-amilase com peso molecular aproximado de 57 kDa, com atividade máxima a 40,7 ºC e pH de 5,1. A pectinesterase foi extraída a pH 6,0 com maior atividade a 49,4ºC e pH 6,6 a maior atividade da poligalacturonase foi a 46 ºC e pH 5,4, quando extraída a pH 8,5.O teor de amido total foi de 8,92%, os grânulos apresentaram morfologia oval em observados em microscopia eletrônica de varredura (MEV). / Maca is an aromatic root that contends 52 to 76 per cent of carbohydrates and is very stable for a long period without signals of deterioration. The degradation mechanisms of the reserve carbohydrates and the cell wall components by enzymatic way had not been described yet. The main objective of this study was the identification of inner enzymes which degrades the starch and the pectins; the others objectives were the analysis and the morphology of the starch grains as well as the root\'s contend composition. The results showed that was obtained the partial purification of a β- amylase, characterized by the molecular mass of 57 kDa, with a highest activity at 40.7 °C and pH 5.1. The pectinesterease was extracted with a pH of 6.0 and its maximum activity was at 49.4 °C and pH 6.6; the polygalacturonase was extracted with a pH of 8.5 and its top activity was achieved at 46 °C and pH 5.4. The total contend of starch was 8.92 % and the grains had an oval morphology observed by SEM.

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