title: [Immobilization of crude laccase onto anion exchange resin and its application in decoloration of malachite green].
abstract: Crude laccase from Trametes versicolor was immobilized onto anion exchange resin D201 by three methods, i.e., direct electrostatic adsorption (D201-Lac-I), crosslinking after electrostatic adsorption (D201-Lac-II) and electrostatic adsorption after treating D201 with glutaraldehyde (D201-Lac-III). Compared to direct electrostatic adsorption, the immobilized laccase amount of D201-Lac-II increased by 4.65 times but the laccase activity was decreased to 4.8%, while the laccase activity on D201-Lac-III increased by 2.99 times, with the immobilization amount decreased to 51%. Shadows of laccase aggregation on D201-Lac-III were found by transmission electron microscopy (TEM). Continuous batch decoloration of malachite green demonstrated that the decoloration efficiency of D201-Lac-III remained in the range of 40% to 55% for more than 210 hours, in addition, the enzyme activity on D201-Lac-III maintained unchanged while the activity of free laccase declined to less than 20% under the same condition. All of the results above indicated that D201-Lac-III had a significantly enhanced stability and good reusability. Considering the low price and simple production procedure of crude laccase, D201-Lac-III could be promising for water treatment purpose.
authors.affiliation: State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093, China. mg0925081@126.com
authors.forename: Xu-liang
authors.initials: XL
authors.lastname: Qi
authors.forename: Xiang
authors.initials: X
authors.lastname: Liu
authors.forename: Bo
authors.initials: B
authors.lastname: Liu
authors.forename: Lin
authors.initials: L
authors.lastname: Wang
authors.forename: Xiao-chun
authors.initials: XC
authors.lastname: Wang
authors.forename: Chao
authors.initials: C
authors.lastname: Fang
mesh_terms: D000838:Anions; D002384:Catalysis; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000737:chemistry*; D005658:Fungi / Q000201:enzymology; D007475:Ion Exchange Resins / Q000737:chemistry*; D042845:Laccase / Q000737:chemistry*; D012394:Rosaniline Dyes / Q000302:isolation & purification* / Q000378:metabolism; D014865:Waste Disposal, Fluid / Q000379:methods; D062065:Wastewater / Q000737:chemistry
chemical_list: D000838:Anions; D004800:Enzymes, Immobilized; D007475:Ion Exchange Resins; D042845:Laccase; D012394:Rosaniline Dyes; D062065:Wastewater; C005095:malachite green