Periconia hispidula um novo biocatalisador do semi?rido para a redu??o de cetonas arom?ticas pr?-quirais

• Ano de defesa: 2013
• Autor(a) principal: GONZ?LEZ, Iv?n Sergio Col?s
• Orientador(a): ALVAREZ, Heiddy Marquez
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: UNIVERSIDADE ESTADUAL DE FEIRA DE SANTANA
• Programa de Pós-Graduação: Mestrado Acad?mico em Biotecnologia
• Departamento: DEPARTAMENTO DE CI?NCIAS BIOL?GICAS
• País: Brasil
• Palavras-chave em Português: ?lcool desidrogenase. C?lulas integras. Compostos carbon?licos pr?-quirais. Fungo.
• Palavras-chave em Inglês: Alcohol dehydrogenase. Whole cells. Prochiral carbonyl compounds. Fungus.
• Área do conhecimento CNPq: CIENCIAS BIOLOGICAS::BIOLOGIA GERAL
• Link de acesso: http://localhost:8080/tede/handle/tede/109

In this work was investigated the biocatalytic action of fungus Periconia hispidula to perform reduction reactions of aromatic prochiral carbonyl compounds. Firstly, the influence of the reaction parameters (medium, time, amount of substrate, forms to use the biocatalyst) over the conversion rate and enantiomeric excess in the reduction of acetophenone was investigated. After the determination of the growth curve, the incubation time prior to addition of substrate, was evaluated (4 and 7 days). For 4 days of preincubation time, the best conversion rate to obtain the (S)-1-phenylethanol with e.e of 98% were achieved. Two types of biocatalysts were evaluated: growing cells and resting cells. The best results were obtained with growing cells. By comparing the results obtained from potato-dextrose (BD) culture medium and potato-dextrose (BD) supplemented with Fe 2+, BD medium supplemented with Fe 2+ (0.02 g / L) was selected. The influence of the amount of acetophenone (20 to 200 ?L) was also examined to evaluate the toxicity of the substrate. Quantities of the substrate higher than 100 ?L (0.1%) decreased also conversion rate but the enantiomeric excess. The applicability of this biocatalyst was also evaluated to reduce acetophenone derivates compounds such as 2, 3 and 4-nitroacetophenone, 2, 3 and 4-methylacetophenone? 2, 3 and 4-methoxyacetophenone, 2, 3 and 4-bromoacetophenone, 2, 3 and 4-fluoracetophenone, 2, 4-dimethylacetophenone, 2, 5-dimethylacetophenone? 4-ethylacetophenone, octanophenone, 1-indanone and 2-indanone. Chiral alcohols were obtained with conversion rates from 8% upto higher than 99% and the enantiomeric excess between 54% up to 100%, indicating that the fungus Periconia hispidula is a promising estereoselctive biocatalyst for use in processes for reducing carbonyl compounds.