title: Decolorization of anthraquinonic dyes from textile effluent using horseradish peroxidase: optimization and kinetic study.
abstract: Two anthraquinonic dyes, C.I. Acid Blue 225 and C.I. Acid Violet 109, were used as models to explore the feasibility of using the horseradish peroxidase enzyme (HRP) in the practical decolorization of anthraquinonic dyes in wastewater. The influence of process parameters such as enzyme concentration, hydrogen peroxide concentration, temperature, dye concentration, and pH was examined. The pH and temperature activity profiles were similar for decolorization of both dyes. Under the optimal conditions, 94.7% of C.I. Acid Violet 109 from aqueous solution was decolorized (treatment time 15 min, enzyme concentration 0.15 IU/mL, hydrogen peroxide concentration 0.4 mM, dye concentration 30 mg/L, pH 4, and temperature 24°C) and 89.36% of C.I. Acid Blue 225 (32 min, enzyme concentration 0.15 IU/mL, hydrogen peroxide concentration 0.04 mM, dye concentration 30 mg/L, pH 5, and temperature 24°C). The mechanism of both reactions has been proven to follow the two substrate ping-pong mechanism with substrate inhibition, revealing the formation of a nonproductive or dead-end complex between dye and HRP or between H2O2 and the oxidized form of the enzyme. Both chemical oxygen demand and total organic carbon values showed that there was a reduction in toxicity after the enzymatic treatment. This study verifies the viability of use of horseradish peroxidase for the wastewaters treatment of similar anthraquinonic dyes.
authors: Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, 11000 Belgrade, Serbia.
authors: Nataša Ž
authors: NŽ
authors: Šekuljica
authors: Innovation Center, Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, 11000 Belgrade, Serbia.
authors: Nevena Ž
authors: NŽ
authors: Prlainović
authors: Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, 11000 Belgrade, Serbia.
authors: Andrea B
authors: AB
authors: Stefanović
authors: Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, 11000 Belgrade, Serbia.
authors: Milena G
authors: MG
authors: Žuža
authors: Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, 11000 Belgrade, Serbia.
authors: Dragana Z
authors: DZ
authors: Čičkarić
authors: Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, 11000 Belgrade, Serbia.
authors: Dušan Ž
authors: DŽ
authors: Mijin
authors: Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, 11000 Belgrade, Serbia.
authors: Zorica D
authors: ZD
authors: Knežević-Jugović
mesh_terms: D000880:Anthraquinones / Q000378:metabolism*; D001557:Benzenesulfonates / Q000378:metabolism*; D004396:Coloring Agents / Q000378:metabolism*; D006735:Horseradish Peroxidase / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D013451:Sulfonic Acids / Q000378:metabolism*; D013696:Temperature; D013783:Textile Industry; D062065:Wastewater
chemical_list: D000880:Anthraquinones; D001557:Benzenesulfonates; D004396:Coloring Agents; D006735:Horseradish Peroxidase; D013451:Sulfonic Acids; D062065:Wastewater; C000606669:C.I. Acid Blue 225; C000606670:C.I. Acid Violet 109