Removal of acetaminophen and carbamazepine in single and binary systems with immobilized laccase from Trametes hirsuta

Laccase-based bioprocesses represent a fascinating prospective for the removal of contaminants of emerging concern in wastewaters. In this work, immobilized laccase from Trametes hirsuta was used to transform carbamazepine (CBZ) and acetaminophen (ACE) in spiked single and binary solutions. The effects of pH, time course and reaction pathways on the transformation were studied. T. hirsuta secreted only laccase. The immobilized laccase was able to degrade 40% and 70% of CBZ and ACE, respectively, in the binary system, while only 5% and 25% of transformation was achieved in the single system for ACE and CBZ, respectively. The maximum removal of acetaminophen was found at pH 7. These obtained results confirm that the acetaminophen is a good laccase mediator compound. The most probable pathway in the binary system involved the formation of acetaminophen dimers and ACE-ACE-CBZ oligomers.