Studies on Fungal Laccase Immobilized by Improved Chitosan

Laccase from Amanita verng was immobilized on chitosan complexed by Cu+ by means of covalent coupling to a glutaradehyde-pretreated support.The condition for immobilizing and part of the qualities of the immobilized enzyme was studied.The optital conditions of immobilization could be specified as: 0.5% glutaradehyde crosslinked for 14 h,added about 1.3 mg free enzyme to immobilized for 12 h or 0.5 h,the recovery of which were 56.4% and 51.2%.Compared with the free enzyme,the affinity of immobilized enzymes decreased to otoluidine while the stability of them was greatly improved.The optital temperature were 40℃ and 80℃,semperately improving 10℃ and 50℃;placed in 90℃ for 5 h,the remaining activity of the immobilized enzyme were 57.4% and 40%,while that of the free enzyme obviously decreased.