Efficient decolorization of an anthraquinone dye by recombinant dye-decolorizing peroxidase (rDyP) immobilized in silica-based mesocellular foam

A recombinant dye-decolorizing peroxidase (rDyP) produced from Aspergillus oryzae was immobilized in synthesized silica-based mesocellular foam (MCF: average pore size 25 nm) and used for decolorization of the anthraquinone dye, Remazol Brilliant Blue R (RBBR). The adsorption yields of rDyP immobilized in MCF increased as the pH decreased from 6 to 3. However, the activity yields of the immobilized rDyP decreased with decreasing pH. The overall efficiency, defined as adsorption yield × activity yield, reached its maximum of 83% at pH 5. In repeated dye-decolorization tests, 20 batches of RBBR could be decolorized by the MCF-immobilized rDyP. MCF showed significantly better performance for rDyP immobilization in term of retaining enzyme activity and dye-decolorization ability compared to previous studies using other mesoporous materials.