Fungal laccase crude extracts: production and pharmaceutical bioremediation

Fungal laccases are eco-friendly biocatalysts capable of oxidizing a broad spectrum of compounds. In this study, four fungal species were cultivated to evaluate laccase production and their application in the bioremediation of acetaminophen and diclofenac. Among these, Pycnoporus sanguineus exhibited the highest laccase activity (1116.94 U/mL). SDS-PAGE profiling of laccase crude extracts (LCEs) revealed multiple protein bands, while zymograms confirmed the presence of distinct isoforms. Stability assays demonstrated that glycerol protected laccase activity in a concentration- and source-dependent manner, with laccase from Trametes sp. 50/08 showing the most gradual decline over 60 days. When examining the efficacy of bioremediation, the LCE from Marasmiellus palmivorus at 10 U/mL achieved 96% acetaminophen removal within 24 h, whereas the LCE from Agaricus blazei at 30 U/mL was the most effective for diclofenac, achieving 82% removal. However, increasing laccase concentration did not enhance pharmaceutical degradation, suggesting possible substrate saturation or inhibition. These findings highlight the efficiency of crude enzyme extracts in removing acetaminophen and diclofenac, reinforcing their potential as sustainable tools for treating pharmaceutical pollutants in aquatic environments.