Kinetics of laccase-catalyzed oxidative polymerization of catechol

Oxidative polymerization of catechol catalyzed by laccase enzyme from Trametes versicolor (ATCC 200801) in aqueous solution containing acetone was investigated in a batch system. The effects of initial catechol and dissolved oxygen concentrations on the initial reaction rate of oxidative polymerization were experimented. An interactive kinetic model as a function of catechol and dissolved oxygen concentrations was developed for enzymatic polymerization and corresponding biokinetic parameters have been evaluated for the first time. The parameters of the model, V-max, K-mm, K-mO2 and K-i were found 0.247 g O-2 m(-3) min(-1), 70.75 g m(-3), 10.4 g m(-3) and 48.15 g m(-3), respectively. The activation energy and reaction rate constant of oxidative catechol polymerization were calculated as 66.8 kJ mol(-1) and 216.3s(-1), respectively. The estimated activation energy and rate constant of the reaction are of the order of magnitude with previously reported values for laccase-catalyzed reactions of different monomers. (C) 2003 Elsevier Science B.V. All rights reserved.