Potential removal of hazardous wastes using white laccase purified by ATPS–PEG–salt system: An operational study

Abstract

Abstract An operational study for the removal of hazardous waste (phenol and resorcinol) in aqueous system was achieved using white laccase purified by polyethylene glycol (PEG)-salt, aqueous-two-phase-system (ATPS). To explore the phase formation various molecular weight and concentration of PEG, types and concentration of salts were optimized using One Factor at a Time (OFAT). Four salts [(NH4)2SO4, Na2SO4, K 2 HPO4, (NH4)2PO4] were selected on the basis of phase formation. ATPS recovered white laccase in saline phase [PEG (10%) 8000, Na2SO 4 (30%)] had specific activity (SA) and purification factor (PF) of 3.6 U mg−1 and 2.5-fold. The recovered laccase successfully removed hazardous waste (1 to 10 mM) at different enzyme loads i.e., 0.67 and 1.34 U mL−1 after 12 h of incubation. At 0.67 U mL−1 load phenol and resorcinol was completely removed (5 mM), whereas 1.34 U mL−1 completely removed resorcinol and 86% phenol (10 mM) after 12 h.