Abstract
This study is mainly related to the characterization of a modified laccase from the Trametes species for use in the oxidative removal of phenolics in aqueous systems. An amphiphilic copolymer, polyalkyleneoxide-co-maleic anhydride was used as a modifier. The modified laccase displayed higher catalytic activity along with improved thermal stability. The modification resulted in a 20- to 10-fold increase in thermal stability at 25 and 40°C, respectively. The kinetic parameters of both the native and the modified laccases were determined by using 2,6-dimethoxyphenol as a substrate. The modified laccase was applied to remove a range of phenolic compounds including chlorophenols, dichlorophenols, trichlorophenols, xylenol, and cresol, which usually behave as pollutants of natural environments. The modified laccase exhibited a remarkably improved efficiency over that of the native laccase in terms of removing various phenolic substances. These results revealed that the enzymatic oxidation by the modified laccases is suitable for the efficient removal of phenolics in aqueous systems.
