Fermentation of molasses by Zymomonas mobilis: effects of temperature and sugar concentration on ethanol production.

Fermentations utilizing strains of Zymomonas mobilis, in place of the traditional yeasts, have been proposed due their ethanol yields being close to theoretical. Ethanol production from sugar cane molasses was analyzed under different culture conditions using Z. mobilis in batch fermentation. The total reducing sugars (TRS) concentrations in the molasses, temperature, agitation and culture time effects were studied simultaneously through factorial design. The best conditions for ethanol production were 200 g L(-1) of total reducing sugars in the molasses, temperature of 30 degrees C and static culture and time of fermentation of 48 h, achieving 55.8 g L(-1). The pH of the medium was kept constant during the experiments, showing that molasses presents a buffering effect.

[1]  J. Laukevics,et al.  The effect of osmo-induced stress on product formation by Zymomonas mobilis on sucrose. , 2000, International journal of food microbiology.

[2]  S. Prapulla,et al.  Response surface methodological approach for the synthesis of isobutyl isobutyrate , 2001 .

[3]  S. Tripetchkul,et al.  Evaluation of Thai agro-industrial wastes for bio-ethanol production by Zymomonas mobilis , 2006 .

[4]  M. Ruth,et al.  Conditioning hemicellulose hydrolysates for fermentation: Effects of overliming pH on sugar and ethanol yields , 2006 .

[5]  P. L. Rogers,et al.  The effect of temperature on the kinetics of ethanol production by strains of Zymomonas mobilis , 1981, Biotechnology Letters.

[6]  T. Jeffries,et al.  Production of ethanol from wood hydrolyzate by yeasts. , 2000 .

[7]  M. Celligoi,et al.  Optimization study for sorbitol production by Zymomonas mobilis in sugar cane molasses , 2005 .

[8]  D. Tribe,et al.  Comparison of Ethanol Production by Different Zymomonas Strains , 1981, Applied and environmental microbiology.

[9]  H. Rodríguez,et al.  Fed‐batch cultivation of Cellulomonas on sugarcane bagasse pith , 1985, Biotechnology and bioengineering.

[10]  Y. Jeon,et al.  Evaluation of wheat stillage for ethanol production by recombinant Zymomonas mobilis , 2005 .

[11]  Wen‐Chien Lee,et al.  Modeling of ethanol fermentation using Zymomonas mobilis ATCC 10988 grown on the media containing glucose and fructose , 2000 .

[12]  H. Doelle,et al.  Fermentation pattern of sucrose to ethanol conversions by Zymomonas mobilis , 1981 .

[13]  P. Rogers,et al.  Evaluation of Zymomonas-based ethanol production from a hydrolysed waste starch stream. , 2006 .

[14]  Rafael Borja,et al.  A comparative kinetic evaluation of the anaerobic digestion of untreated molasses and molasses previously fermented with Penicillium decumbens in batch reactors , 2004 .

[15]  Subba Rao Somalanka,et al.  Optimization of fermentation conditions for the production of ethanol from sago starch by co-immobilized amyloglucosidase and cells of Zymomonas mobilis using response surface methodology. , 2006 .

[16]  Michael Somogyi,et al.  A NEW REAGENT FOR THE DETERMINATION OF SUGARS , 1945 .

[17]  J. S. Hunter,et al.  Statistics for experimenters : an introduction to design, data analysis, and model building , 1979 .

[18]  K. Tanaka,et al.  Investigation of the utility of pineapple juice and pineapple waste material as low-cost substrate for ethanol fermentation by Zymomonas mobilis. , 1999, Journal of bioscience and bioengineering.

[19]  Peter L. Rogers,et al.  Ethanol production by Zymomonas mobilis , 1982 .

[20]  F. Tao,et al.  Ethanol fermentation by an acid-tolerant Zymomonas mobilis under non-sterilized condition , 2005 .

[21]  G. Sprenger.  Carbohydrate metabolism in Zymomonas mobilis: a catabolic highway with some scenic routes , 1996 .

[22]  T. Conway,et al.  Kinetics of Sugar Transport and Phosphorylation Influence Glucose and Fructose Cometabolism by Zymomonas mobilis , 1997, Applied and environmental microbiology.

[23]  C. J. McGrath,et al.  Effect of exchange rate return on volatility spill-over across trading regions , 2012 .

[24]  J. S. Hunter,et al.  Statistics for Experimenters: An Introduction to Design, Data Analysis, and Model Building. , 1979 .

[25]  S. C. Basappa,et al.  Optimization and interaction of media components in ethanol production using Zymomonas mobilis by response surface methodology. , 1999, Journal of bioscience and bioengineering.