Renewable Energy, Vol.160, 1206-1216, 2020
Impact of the Melle-Boinot process on the enhancement of second-generation ethanol production by Spathaspora passalidarum
This study aimed to elucidate the impact of temperature on the first-generation fermentation process (Melle-Boinot) applied to second-generation ethanol production by the native xylose-fermenting yeast Spathaspora passalidarum. The Melle-Boinot process consists of fed-batch fermentations with cell recycling and was performed in this study under three conditions: fixed temperature of 30 degrees C, temperature decay of 1 degrees C per cycle and fixed temperature of 27 degrees C. The physiological adaptation of S. passalidarum was observed throughout the recycles under all conditions regardless of the temperature applied, as confirmed by the improvement in the kinetic and fermentation parameters. Regarding the fixed 30 degrees C condition, the best condition of this study for industrial application, the ethanol yield, ethanol volumetric productivity and ethanol titer increased 31.77, 33.58 and 33.55%, respectively, from the first to last fermentation cycle. The Melle-Boinot fermentation process was shown to be a worthy strategy for second-generation ethanol production by native yeasts without the need for genetic modifications. (C) 2020 Elsevier Ltd. All rights reserved.
Keywords:Second-generation ethanol;Pentose fermentation;Native yeasts;Spathaspora passalidarum;fed-Batch;Cell recycle