Hydrodynamic Cavitation-Assisted Photo-Fenton Pretreatment and Yeast Co-Culture as Strategies to Produce Ethanol and Xylitol from Sugarcane Bagasse

This study explored innovative approaches to produce ethanol and xylitol from sugarcane bagasse using a hydrodynamic cavitation-assisted photo-Fenton process as the pretreatment, and yeast co-culture for hydrolysate fermentation. Pretreatment conditions were optimized (20 mg/L of iron sulfate, pH 5.0, and reaction time of 14 min) resulting in glucan and xylan hydrolysis yields of 96% and 89%, respectively. The hydrolysate produced under these conditions was fermented using a co-culture of Saccharomyces cerevisiae IR2 (an ethanol-producing strain) and Candida tropicalis UFMGBX12 (a xylitol-producing strain). Optimal co-culture conditions consisted of using an inoculum concentration of 1.5 g/L for each yeast strain. After 36 h of fermentation, ethanol and xylitol concentrations reached 20 g/L and 13 g/L, respectively. These results demonstrate the potential of combining hydrodynamic cavitation-assisted photo-Fenton pretreatment with co-culture fermentation to simultaneously produce ethanol and xylitol. This strategy presents a promising approach for enhancing the efficiency of lignocellulosic biorefineries.