title: Laccase-catalyzed removal of bisphenol-A from water: protective effect of PEG on enzyme activity.
abstract: The feasibility of using the enzyme laccase to treat synthetic wastewater containing bisphenol-A (BPA) was examined. Optimization of pH, laccase concentration, polyethylene glycol (PEG) as an additive for >95% conversion and precipitation of BPA over 3 h of reaction period was determined through colorimetric assay and HPLC. PEG reduced enzyme inactivation, allowing a 5.2-fold reduction in the amount of laccase required for >95% removal of BPA in the range of 0.1-1 mM over 3 h. The fate of PEG after the reaction was also monitored. Linear relationships were found between the concentration of BPA (0.1-1 mM) and the optimum concentrations of laccase and PEG. Little PEG remained in the solution when up to 75 mg/L of PEG was used to treat 0.5 mM BPA. Beyond this level, PEG concentration increased linearly in the supernatant. It is inferred that an interaction between PEG and the polymeric products resulted in the protection of laccase.
authors.affiliation: Department of Civil and Environmental Engineering, University of Windsor, Windsor, Ontario Canada N9B 3P4. modares@uwindsor.ca
authors.forename: Katy
authors.initials: K
authors.lastname: Modaressi
authors.forename: K E
authors.initials: KE
authors.lastname: Taylor
authors.forename: J K
authors.initials: JK
authors.lastname: Bewtra
authors.forename: N
authors.initials: N
authors.lastname: Biswas
mesh_terms: D001559:Benzhydryl Compounds; D002384:Catalysis; D004795:Enzyme Stability; D006863:Hydrogen-Ion Concentration; D042845:Laccase / Q000378:metabolism*; D010636:Phenols / Q000302:isolation & purification* / Q000378:metabolism; D011092:Polyethylene Glycols / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000302:isolation & purification* / Q000378:metabolism; D018508:Water Purification / Q000379:methods; D000098826:Bisphenol A Compounds
chemical_list: D001559:Benzhydryl Compounds; D042845:Laccase; D010636:Phenols; D011092:Polyethylene Glycols; D014874:Water Pollutants, Chemical; C006780:bisphenol A; D000098826:Bisphenol A Compounds