Immobilization of levan-xylanase nanohybrid on an alginate bead improves xylanase stability at wide pH and temperature.

Despite the sustainable availability, levan, a fructose based natural polysaccharide has not received significant attention in the development of enzyme immobilization technology. Herein, we prepared levan-xylanase (LXy) nanohybrid and characterized by scanning electron microscopy, particle size analyzer and zeta potential. To prevent the enzyme leakage from the nanohybrid, LXy was immobilized onto an alginate beads (NaAlg). Immobilization yield was optimized using a statistical method, central composite design. A maximum immobilization yield of 95.3% was achieved at 2.13% (w/v) of sodium alginate, 2.14% (w/v) of calcium chloride, 64min of curation time and 1.4mm bead size. Immobilized LXy retains nearly 80% of the enzyme activity at a wide range of temperature (20-90°C) and pH (3-10). Immobilization of LXy onto NaAlg increases the activation energy from 28.50Jmol-1K-1 to 39.38Jmol-1K-1. Collectively, this result implies that LXy immobilized onto NaAlg increases the enzyme stability and retains its activity.