Single-bath cost-effective and eco-friendly enhancement of wool fiber using immobilized cutinase on magnetic nanoparticles

Wool, a widely used animal fiber, contains impurities such as waxes, lanolin and dirt which require removal during scouring. Conventional chemical scouring methods, while effective, pose environmental concerns due to hazardous chemical release, high water consumption and chemical residues that affect subsequent dyeing. This study explores an eco-friendly alternative using fungal cutinase immobilized on magnetic nanoparticles (Fe-NPs) for wool bio-scouring. Immobilization enhances enzyme stability, reusability and efficiency, addressing challenges associated with free enzyme applications. Using Response Surface Methodology (RSM), key immobilization parameters were optimized, achieving 85% enzyme activity retention and a threefold increase in thermal stability compared to the free enzyme. Immobilized cutinase-treated wool exhibited a 32% increase in wettability and a 27% reduction in residual grease content, comparable to chemical scouring. Additionally, the enzyme maintained 85% activity after five reuse cycles, demonstrating enhanced operational stability. Despite its promise, limitations such as enzyme stability, reusability and efficiency have hindered widespread adoption of bio-scouring. This study highlights the need for further research on alternative immobilization techniques (e.g., covalent bonding, cross-linking), dye compatibility and integration into continuous processing systems. Additionally, combining bio-scouring and dyeing in a single step could further reduce water and energy consumption, making wool processing more sustainable. Future work should focus on industrial-scale validation and long-term performance assessment of immobilized cutinase for commercial application.