Process optimization of cellulase-catalyzed hydrolysis of pretreated sugarcane bagasse

Abstract

The sustainable conversion of lignocellulosic biomass into fermentable sugars is central to developing bio-based polymers and fuels. Despite its promise, one persistent challenge is the high cost and limited efficiency of cellulase enzymes, which form a substantial part of operating expenses in biorefineries. This study focused on optimizing cellulase activity for hydrolysis of pretreated sugarcane bagasse, a widely available agro-industrial residue. Enzyme dosage, incubation temperature, and hydrolysis time were systematically varied. Results showed that increasing enzyme load improved sugar release up to 15 FPU/g substrate, beyond which yields plateaued, reflecting substrate saturation. Hydrolysis was most effective at 50 °C, balancing kinetic activity and enzyme stability. Incubation for 48 h yielded maximum sugar release, with extended times resulting in only marginal or even reduced gains, likely due to product inhibition and enzyme deactivation. These findings demonstrate that careful tuning of cellulase activity is essential not only for yield optimization but also for cost reduction. Establishing such parameters provides a pathway for more economically viable biomass-to-biopolymer conversion processes.