Elimination of carbamazepine by repeated treatment with laccase in the presence of 1-hydroxybenzotriazole

Carbamazepine (CBZP) is used as an antiepileptic drug and is highly persistent. In this study, CBZP was treated with laccase from white rot fungus Trametes versicolor in the presence of a redox mediator 1-hydroxybenzotriazole (HBT). A single treatment with laccase and HBT eliminated CBZP by about 22% after 24 h, and repeated treatments with laccase and HBT, which were added to the reaction mixture every 8 h, helped eliminate about 60% of CBZP after 48 h. This suggests that repeated treatment is effective in eliminating CBZP. Mass spectrometric analyses demonstrated that two degradation products of CBZP, 10,11-dihydro-10,11-epoxycarbarnazepine and 9(10H)-acridone, were formed via repeated treatment with laccase and HBT. (C) 2010 Elsevier B.V. All rights reserved.