Study of ethanol production by Pichia stipitis using rice straw hydrolysate

• Grant number: 05/01168-6
• Support Opportunities: Scholarships in Brazil - Master
• Effective date (Start): September 01, 2005
• Effective date (End): December 31, 2006
• Field of knowledge: Biological Sciences - Microbiology - Applied Microbiology
• Principal Investigator: Ines Conceicao Roberto
• Grantee: João Paulo Alves Silva
• Host Institution: Escola de Engenharia de Lorena (EEL). Universidade de São Paulo (USP). Lorena , SP, Brazil

Abstract

The present project aims to study the ethanol production from lignocellulosic materials using rice straw hemicellulosic hydrolysate as substrate and Pichia stipitis as biocatalyst. For this purpose, the effect of the nutritional supplementation and the aeration level on the fermentative process will be evaluated. In a first step, a full factorial design 24 will be used to verify the individual effect and the interaction effect of nutrients (KH2PO4; (NH4)2PO4; MgSO4 7H2O and yeast extract) on the fermentation parameters. Based on the results obtained, assays will be conducted to optimize the medium composition. In the second step, the substrate containing optimized nutritional composition will be subjected to another set of fermentative runs for determining the agitation and aeration conditions that maximize the ethanol productivity and bioprocess yield. For this, an experimental design 22 will be adopted taking into consideration as experimental factors the agitation rate and the flask volume/ medium volume ratio.The optimization of these conditions will be based on multivariate analysis concepts. This project is inserted within the research program of Applied Microbial and Bioprocess Laboratory from the Biotechnology Department FAENQUIL which aims to develop technologies for utilization of lignocellulosic materials, especially agro-industrial residues to obtain fuels and chemicals by biotechnological routes