Characterization and immobilization of Trametes versicolor laccase on magnetic chitosan-clay composite beads for phenol removal.

Laccase from Trametes versicolor was immobilized on magnetic chitosan-clay composite beads by glutaraldehyde crosslinking. The physical, chemical, and biochemical properties of the immobilized laccase and its application in phenol removal were comprehensively investigated. The structure and morphology of the composite beads were characterized by SEM, TGA, and FTIR analyses. The immobilized laccase showed better storage stability and higher tolerance to the changes in pH and temperature compared with free laccase. Moreover, the immobilized laccase retained more than 75% of its original activity after 10 cycles. The efficiency of phenol removal by immobilized laccase was about 80% under the optimum conditions after 4 h.