The comprehensive utilization of mixed sugars in lignocellulose hydrolysate and the improvement of tolerance to fermentation inhibitors in lignocellulose hydrolysate have always been the key issues in the utilization of lignocellulose hydrolysate. Spathaspora passalidarum, as an unconventional yeast, has the ability of natural co-fermentation of xylose and glucose. In this study, two aeration strategies were used to further improve the fermentation ability of the strain. 50 g/L mixed sugar [m(glucose mass)∶m(xylose) mass=1∶1], when no hydrolysis inhibitor was added, the fermentation ended at 36 h, and the sugar-alcohol conversion rate was 0.46 g/g. After adding lignocellulose hydrolysis inhibitor, the fermentation could not be finished for 96 h, and the sugar-alcohol conversion was only 0.09 g/g, and xylose could hardly be utilized. Using oxidation-reduction potential (ORP) control strategy, when the optimal ORP setting value is -110 mV, the fermentation finished in 48 h, and the conversion rate of sugar to alcohol is 0.47 g. Constant ventilation could also promote the fermentation process of mixed sugar with hydrolytic inhibitors, but the effect was worse than that of ORP control strategy. The adverse effects of Maillard reaction could be avoided by adjusting the mixed sugar medium with added inhibitors to pH 3 to sterilize, and then adjust the fermentation medium pH to 5, with control ORP to -110 mV, the fermentation time was only 24 h, at the same time, the conversion rate of sugar and alcohol was 0.47 g/g, which lays a foundation for the efficient utilization of non-detoxified lignocellulose hydrolysate.
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