The immobilized laccase Tplac from white rot fungus
T. pubescens was fabricated by entrapment onto chitosan beads
using the crosslinker glutaraldehyde. Optimization experiments
indicated that the stability was dependent on the concentration of
crosslinker, crosslinking time, volume of enzyme, and immobilization
time. Moreover, the immobilized laccase was less sensitive
to changes in pH and temperature, and to storage time, compared
with free laccase, thereby exhibiting better stability and reusability.
Catalytic performance of immobilized Tplac was evaluated by
degradation of various synthetic dyes, showing that the removal
efficiency of metal-complex dye Acid Black 172 by immobilized
Tplac (68.84%) was 1.22 times higher than that by free laccase.
These results suggested that immobilization is feasible to improve
the conformational stability of laccase for many industrial
applications.