Sustainable integrated co-production of bioactive xylooligosaccharides and second-generation ethanol from energy cane bagasse

Abstract

Energy cane bagasse is an abundant lignocellulosic biomass with untapped potential for biorefinery use. This study aimed to enhance the valorization of energy cane bagasse through an integrated process for co-producing bioactive xylooligosaccharides (XOS) and ethanol. Xylan extraction via alkaline hydrogen peroxide (AHP) pretreatment, followed by enzymatic hydrolysis using crude xylanases from Aspergillus flavus KUB2, yielded a high XOS concentration of 421.15 mg/g at 24 h, primarily as xylobiose (X2). The produced XOS demonstrated significant bioactivity, including promoting probiotic bacterial growth, increasing short-chain fatty acid (SCFA) production, and exhibiting considerable antioxidant activity. The remaining cellulose-rich solids were subsequently converted into second-generation biofuel. Fermentation of this residue yielded a final ethanol concentration of 31.08 g/L, achieving a theoretical yield of 89.46 % and 0.46 g/g ethanol yield. These findings demonstrate the feasibility of using energy cane bagasse for co-producing functional food ingredients and ethanol, supporting economic and sustainable biorefinery development. © 2025 The Authors