Utilize este identificador para referenciar este registo: http://hdl.handle.net/10400.5/3345
Título: Bioetanol a partir de hidrolisados lenhocelulósicos simulados. Avaliação preliminar do papel das vias de regulação em Saccharomyces cerevisiae
Autor: Torres, Mafalda Honório
Orientador: Prista, Catarina Paula Geoffroy
Dias, Maria da Conceição Loureiro
Palavras-chave: lignocellulosic bioethanol
lignocellulosic hydrolysates
fermentation
yeast
bioetanol lenhocelulósico
hidrolisados lenhocelulósicos
fermentação
levedura
Data de Defesa: 2010
Editora: ISA
Resumo: Bioethanol production from lignocellulosic materials is only viable if the process of converting the biomass to ethanol is efficient. One of the conditions that affect this efficiency is the resistance of the fermentative microorganisms to the toxic compounds that are formed during the necessary lignocellulosic materials pre-treatment. The current work analyzed the behavior of Saccharomyces cerevisiae growing on a medium containing inhibitory compounds to the fermentation, compounds that are present on an industrial lignocellulosic hydrolysate. The effect of the elimination of non-essential genes on the cells fermentative metabolism was studied. The non-essential genes eliminated were genes involved in the regulation and metabolism of nitrogen (TOR1, GLN3, PRO1, PUT4, ARO4), in the cell’s response to oxidative stress (SOD2, ZWF1, ADH6), osmotic stress (HOG1, TPS1, NTH1, HSP12) and general stress (HSP26), on the regulation of the intracellular pH (RIM101, VMA1), and in apoptosis (AIF1, FIS1). The results obtained from these procedures were indicative that some of these genes mutations are relevant for determining the fermentation efficiency. The behavior of four selected mutant strains was further characterized. Besides the determination of glucose concentration, extracellular pH and CFU at the beginning of stationary phase and glucose exhaustion, for these four chosen strains, the ethanol concentration and the influx and efflux of protons through the plasmatic membrane were also collected.
Descrição: Mestrado em Engenharia de Sistemas Bioenergéticos - Instituto Superior de Agronomia
URI: http://hdl.handle.net/10400.5/3345
Aparece nas colecções:BISA - Dissertações de Mestrado / Master Thesis

Ficheiros deste registo:
Ficheiro Descrição TamanhoFormato 
Mafalda.Torres.doc3,95 MBMicrosoft WordVer/Abrir    Acesso Restrito. Solicitar cópia ao autor!


FacebookTwitterDeliciousLinkedInDiggGoogle BookmarksMySpace
Formato BibTex MendeleyEndnote Degois 

Todos os registos no repositório estão protegidos por leis de copyright, com todos os direitos reservados.