Agro-industrial-Produced Laccase for Degradation of Diclofenac and Identification of Transformation Products

Abstract

A widely used anti-inflammatory drug, diclofenac (DCF), is recalcitrant in many environmental compartments and poses threat to several aquatic and terrestrial organisms. Enzymatic degradation of emerging contaminants which are often micropollutants, has gained interest for the past few years. However, production of enzymes often incurs high costs. In this study, ligninolytic enzyme laccase was produced by white rot fungi Tremetes versicolor (ATCC 20869) using agro-industrial residues, apple pomace (AP), pulp and paper solid waste (PPSW), and alfa fibers as substrates. Various known inducers for laccase production, such as tween 80 (0.1% (w/w)), veratryl alcohol (3 mM Kg–1), CuSO4 (3 mM Kg–1), and phenol red (3 mM Kg–1) were used to enhance laccase production. A maximum laccase activity of 49.16 ± 4.5, 52.4 ± 2.2, and 14.26 ± 0.8 U/gds (units/gram dry substrate) was obtained from apple pomace, PPSW, and alfa plant fibers, respectively, at optimal experimental conditions. Further, the kinetics of the laccas...