Construction and Performance Assessment of an Enzymatic Reactor for Xylulose Synthesis from Hemicellulose

Abstract

Xylulose has broad application prospects in fields such as biomanufacturing, bioenergy, pharmaceuticals, and materials. Enzyme-catalyzed synthesis of xylulose from hemicellulose faces challenges such as enzyme deactivation, low reusability, and high industrial costs. To address these issues, our study employed large-pore resin Amberlyst-15(A-15) as a carrier to immobilize both xylanase and xylose isomerase enzymes. The method involved amino-functionalization of the resin using a Macroporous Ion Exchange Resins A-15’s catalytic properties towards hemicellulose for xylose. The immobilization of xylanase and xylose isomerase was achieved through adsorption-crosslinking, successfully combining organic and enzymatic catalysis. By optimizing the enzyme-catalyzed conditions and immobilization methods, stable and active immobilized enzymes were prepared, with investigations into the effects of crosslinkers, crosslinker concentrations, and crosslinking times, leading to the identification of optimal production conditions. The reaction was conducted at 50 °C in a pH 5.5 buffer system for 12 h, the immobilized dual-enzyme prepared by the adsorption-crosslinking method achieved a hemicellulose conversion rate of 56.60%, significantly higher than that of free enzymes. The immobilized enzyme exhibited higher relative activity than the free enzyme at 80 °C and maintained significantly higher relative activity after 15 days of storage.

Graphical Abstract