Enhancing lignocellulosic biomass conversion for bioethanol production via arabinofuranosidase-mediated cell wall remodeling in tobacco

Lignocellulosic biomass is a key renewable resource for sustainable bioenergy production; however, its efficient conversion remains limited by intrinsic cell wall recalcitrance. Here, we present a novel strategy to enhance biomass processability in a dicot model by targeted modification of arabinose-containing matrix polysaccharides. A codon-optimized abfB gene encoding a fungal α-L-arabinofuranosidase from Aspergillus nidulans was constitutively expressed in tobacco (Nicotiana tabacum). Transgenic lines exhibited stable transgene expression and significantly increased enzymatic activity without compromising plant growth, biomass accumulation, or reproductive performance. Despite the absence of major changes in lignocellulosic composition, detailed cell wall analyses (monosaccharide profiling, FTIR, and Py-GC–MS) revealed subtle modifications in cell wall architecture. These structural changes translated into a substantial improvement in biomass conversion efficiency, with ethanol yields increased by up to 50% during simultaneous saccharification and fermentation. Our results demonstrate that targeted remodeling of arabinose-rich matrix polysaccharides reduces biomass recalcitrance by altering cell wall organization rather than composition. This strategy provides a promising approach for enhancing the bioenergy potential of dicot biomass crops while maintaining agronomic performance, highlighting its relevance for sustainable lignocellulosic biofuel production.