Abstract

Background: Fermentation strategies for bioethanol production that use flocculating Saccharomyces cerevisiae yeast need to account for the mechanism by which inhibitory compounds, generated in the hydrolysis of lignocellulosic materials, are tolerated and detoxified by a yeast floc. Results: Diffusion coefficients and first-order kinetic bioconversion rate coefficients were measured for three fermentation inhibitory compounds (furfural, hydroxymethylfurfural, and vanillin) in self-aggregated flocs of S. cerevisiae NRRL Y-265. Thiele-type moduli and internal effectiveness factors were obtained by simulating a simple steady-state spherical floc model. Conclusions: The obtained values for the Thiele moduli and internal effectiveness factors showed that the bioconversion rate of the inhibitory compounds is the dominant phenomenon overmass transfer inside the flocs. (C) 2019 Pontificia Universidad Catolica de Valparaiso. Production and hosting by Elsevier B.V. All rights reserved.