Abstract: The hollow globular chitosan was made by dissolving in 20% HCl first and then injecting 25% chitosan solution into 15% NaOH and 30% CH3OH mixture and coagulating into 2mm hollow globular chitosan. The hollow globular chitosan was treated with 4% gluluraldehyde, then immobilized withα-amylase, β-amylase and Brulan enzyme at 25℃ for 2h, respectively. The best reaction pH of the immobilized enzymes decreased about 1 unit, the reaction temperature of the immobilizing enzymes increased about 10℃.The relative activity of enzyme on the immobilized α-amylase and the immobilized β-amylase became 7.2% and 22.3%, respectively. The content of isomaltooligosaccharide reached 38.9% in the bioreactor.

Key words: isomaltooligosaccharide, immobilizing enzymes, hollow globular chitosan