Monday, May 5, 2008
7-39

Influence of nutrient supplementation on ethanol batch production rates

Renata M. R. G. Almeida, Alessandra M. dos Santos, Bertony P. C. da Silva, and Evandir G. de Oliveira. Technology Center, Federal University of Alagoas, Campus A. C. Simoes, Via Br 104-North, Km 97, Tabuleiro dos Martins, Maceio, Brazil

Ethanol is a renewable energy source produced through fermentation of sugars unlike the fossil fuels. On account of limited global supply of oil, ethanol has reemerged as an alternative to petroleum-based liquid fuels. During fermentation, activities of Saccharomyces cerevisiae closely respond to changes in the environmental conditions, which are accompanied by variations in the mass transfer around and the metabolic behavior of the microorganisms. To ethanol production the yeast requires not only a simple carbon source but also vitamins and others nutrients mainly nitrogen, phosphorus, potassium among others. The nutritional necessities of the yeast during alcoholic fermentation processes influence the cellular growth and the efficiency of ethanol production. The aim of this work was study the influence of nutrients supplementation of the cane molasses and sugar cane musts on the batch ethanol production. Batch fermentation experiments were carried out with different sucrose initial concentrations of cane molasses and sugar cane musts as the sole carbon source for S. cerevisiae. The nutrients supplementation was done with some commercial products with different nutrients in it and at least thee initial concentrations of the commercial nutrients formulation were used. Fermentation flasks were then shaken in the incubator at 200 rpm and 32ºC. The musts were analyzed to determine the amount of each nutrient before the supplementation. Samples were withdrawn and after analysis production rates like fermentative efficiency, productivity and yield were calculated. The results consequently provide a better understanding of nutrients supplementation effects on the cell activities for further development of the process.


Web Page: www.ufal.br

See more of Poster Session Two
See more of General Submissions

See more of The 30th Symposium on Biotechnology for Fuels and Chemicals (May 4 -- 7, 2008)