Fabrication of immobilized xylanase by a novel 3D electrostatic printing as an excellent catalyst for corn straw degradation

Extrusion-based 3D printing has been widely utilized in enzyme immobilization to obtain the desired shape, even though the result is less fine. Here, we report a novel 3D electrostatic printing (3DEP) technology that combines the technologies of electrospinning and 3D printing to manufacture fiber membranes that are finer and uniform and used them for xylanase immobilization. After optimizing the preparation conditions for the 3DEP immobilization carrier, the finer, uniform fiber membranes were printed by using a ratio of 10:1 polyvinyl alcohol (PVA) and chitosan (Cs) under a constant voltage (5 kV) and feed rate (0.001 mm/s). Additionally, 50% glutaraldehyde (GA) vapor was used for cross-linking Cs in order to improve the water insolubility of the support. The 3DEP immobilized xylanase was then prepared by mixing xylanase and the printed materials. The resulting immobilized xylanase exhibited excellent stability, with over 95% of enzyme activity following storage for 28 days, and 53% xylan conversion was still retained after reuse over 8 batches. Finally, the 3DEP immobilized xylanase featured good catalytic efficiency in degrading corn straw. Collectively, the results of this study show that 3DEP offered a finer carrier manufacturing technology and could improve the catalytic efficiency of the immobilized enzyme .