Abstract
Studies were conducted on maltodextrin saccharification and on simultaneous saccharification and fermentation (SSF) with various commercial glucoamylases. In kinetics studies, none of the glucoamylases were able to completely convert maltodextrin into glucose. Typically, about 85% conversion was obtained, and glucose yields were about 75%. Typically, the kinetics were biphasic, with 1 h of rapid conversion, then a significant reduction in rate. Data were consistent with strong product inhibition and/or enzyme inactivation. Some glucoamylases followed first-order kinetics, initially slower at dextrin conversion, but eventually achieving comparable conversion and glucose concentrations. Most of the glucoamylases were more active at 55°C than at 35°C, but pH had little effect on activity. Screening studies in an SSF system demonstrated little difference between the glucoamylases, with a few exceptions. Subsequent targeted studies showed clear differences in performance, depending on the fermentation temperature and yeast used, suggesting that these are key parameters that would guide the selection of a glucoamylase.
Similar content being viewed by others
References
Christenson, U. (2000), Biochem. J. 349, 623–628.
Nagy, E., Belafi-Bako, K., and Szabo, L. (1992), Starch/Staerke 44, 145–149
Cepeda, E., Hermosa, M., and Ballesteros, A. (2001), Biotechnol. Bioeng. 76, 70–76.
Peeva, L. and Yankov, D. (2000), Bioprocess Eng. 22, 397–401.
Allain, E. (2004), Lab-Scale Modelling of Fuel Alcohol Fermentations, presented at the 20th Fuel Ethanol Workshop, Madison, WI.
Ingledew, M. (1999), In: The Alcohol Textbook, 3rd edition, Jacques, K. A., Lyons, T. P., and Kelsall, D.R. (eds.), Alltech, Inc.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Saville, B.A., Huang, C., Yacyshyn, V. et al. Properties and performance of glucoamylases for fuel ethanol production. Appl Biochem Biotechnol 129, 180–194 (2006). https://doi.org/10.1385/ABAB:129:1:180
Issue Date:
DOI: https://doi.org/10.1385/ABAB:129:1:180