Fatemeh Salami - ۱Department of Pure Chemistry, Faculty of Chemistry, Shahid Beheshti University, G.C., Tehran, Iran
Zohreh Habibi - Department of Pure Chemistry, Faculty of Chemistry, Shahid Beheshti University, G.C., Tehran, Iran
Mehdi Mohammadi - Bioprocess Engineering Department , Institute of Industrial and Environmental Biotechnology, National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran, Iran
Maryam Yousefi - Nanobiotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran

In present study, laccase from Myceliophthora thermophila, was immobilized on epoxyfunctionalized silica via one-pot three component reaction. In the immobilization process, regarding our previous reports, three functional groups including carboxylic acid from the enzyme, epoxy groups from the support and isocyanide from the reaction medium have been participated . The results revealed immobilization of 10-40 mg of laccase on 1 gr of the supports in 12h. The immobilized enzyme exhibited remarkable activity (50 U/g) with improved stability towards pH, temperature, storage and organic solvent tolerance. Immobilized laccase was used for the decolorization of five texetile dyes (Acid orange 156, acid red 52, coomassie brilliant blue, Methyl violet, Malachite Green) with or without the redox mediators such as 1-hydroxybenzotriazole (HBT), catechol, syringaldehyde and N-hydroxyphthalimide (HPT). The reaction was carried out with stirring (250 rpm) sodium acetate buffer (pH 4.5) at 40 ◦C for 6 hours. Our data suggest that studied laccase/mediator systems were effective biocatalysts for the treatment of textile dyes.

Myceliophthora thermophila laccase, Epoxy-functionalized silica, Covalent immobilization, Isocyanide, Decolorization, Textile dyes