Saccharomyces cerevisiae ethanol production

Fermentation of sugar by Saccharomyces cerevisiae, for production of ethanol in an immobilised cell reactor (ICR), was successfully carried out to improve the performance of the... 

Owing to diminishing fossil fuel reserves, alternative energy sources need to be renewable, sustainable, efficient, cost-effective, convenient and safe.1 In recent decades, microbial production of ethanol has been considered as an alternative fuel for the future because fossil fuels are depleting. Several microorganisms, including Clostridium sp. and yeast, the well-known ethanol producers Saccharomyces cerevisiae and Zymomonas mobilis, are suitable candidates to produce ethanol.2,3... 

Example 12.7 Develop a model for the anaerobic batch fermentation of glucose to ethanol and coproduct CO2 using Saccharomyces cerevisiae. The starting mixture contains 10% glucose. The inoculum is 0.0005 w/w. Product inhibition stops cell growth at 14% ethanol. Assume ka = 0 but include the cannibalization of cellular material beginning when the substrate is completely consumed. 

Continuous extraction loop reactor Ethanol production with glucose fermentation Saccharomyces cerevisiae 126... 

A trivial yet important application is following ethanol production via a bioprocess. Sivakesava et al.1 simultaneously measured glucose, ethanol, and the optical cell density of Saccharomyces cerevisiae during ethanol fermentation, using an off-line approach. Samples were brought to an instrument located near the fermentation tanks and the measurements made in short order. While they eventually used MIR due to the interfering scatter of the media, they proved that Raman could be used for this application. 

Cira LA et al (2008) Heterologous expression of Fusarium oxysporum tomatinase in Saccharomyces cerevisiae increases its resistance to saponins and improves ethanol production during the fermentation of Agave tequilana Weber var. azul and Agave salmiana must. Antonie Van Leeuwenhoek. Int J Gen Mol Microbiol 93 259... 

Hayes, W.A., Ethanol production from glucose by Saccharomyces cerevisiae in an anaerobic gas-solid fluidised bed fermenter, PhD thesis. University of Lincolnshire and Humberside, 1998. 

Moebus, O. and Teuber, M., Production of ethanol by solid particles of Saccharomyces cerevisiae in a fluidized bed, Eur. ]. Appl. Microbiol. Biotechnol., 15 (1982a) 194-197. 

Thibault, J., Le Duy, A. and Cote, E, Production of ethanol by Saccharomyces cerevisiae under high-pressure conditions. Biotech. Bioeng., 30 (1987) 74-80. 

The fifth paper, "A Separative Bioreactor Direct Product Capture and pH Control," presented by Seth Snyder of the Argonne National Laboratory, reviewed development and performance of a novel bioreactor incorporating electrodeionization to simultaneously produce and separate products from both enzymatic and microbially mediated reactions. The sixth paper, " Optimization of Xylose Fermentation in Spent Sulfite Liquor by Saccharomyces cerevisiae 259ST," presented by Steven Helle of the University of British Columbia, provided an overview of an approach to fermentation optimization utilized to identify key process variables limiting use of the SSL for commercial ethanol production. 

Fig. 1. Redox metabolism in Saccharomyces cerevisiae during anaerobic growth on glucose. The ethanol yield is lowered by the production of biomass and glycerol. The glycerol flux, x, can be decreased, and the ethanol yield thereby increased if the stoichiometric coefficient a for biomass formation is reduced, e.g., by having nitrogen assimilation via an NADH-depen-dent glutamate dehydrogenase [10]...

Karimi, K., Emitiazi, G., and Taherzadeh, M. J. 2006. Ethanol production from dilute-acid pretreated rice straw by simultaneous saccharification and fermentation with Mucor indicus, Rhizopus oryzae, and Saccharomyces cerevisiae. Enz Microbial Technol., 40,138-144. 

Ohta, K., Hamada, S., and Nakamura, T. 1993. Production of high concentrations of ethanol from inulin by simultaneous saccharification and fermentation using Aspergillus niger and Saccharomyces cerevisiae. App. Environ. Microbiol, 59, 729-733. 

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