Entrapment of DyP-type peroxidase from Pseudomonas fluorescens Pf-5 into Ca-alginate magnetic beads

The aim of this study was to investigate the optimal conditions for the immobilization and stabilization of DyP1B dye decolorizing peroxidases type B (DyP1B) from Pseudomonas fluorescens Pf-5 immobilized in Ca-alginate ferromagnetic beads. The immobilized DyP1B was used in the degradation of the Reactive Blue 5 (RB5) synthetic dye. The enzyme was successfully entrapped in a Ca-alginate matrix and showed an encapsulation efficiency of 94%. The concentration of DyP1B (0.8 mg mL^-1 ), 2% of alginate and magnetite (10.0 mg mL^-1 ) was optimal for immobilization. The immobilized DyP1B showed optimum activity at pH 7.0 and 40 °C compared with pH 5.5 and 30 °C for free peroxidase. Reusability studies showed that after five cycles, the immobilized DyP1B system retained more than 58% of its initial activity. The immobilized DyP1B was able to decolorize RB5 at concentrations of 0.1, 0.05, and 0.01% (w v^-1 ) with efficiency rates of about 20, 29, and 45%, respectively. The immobilization of DyP1B in alginate beads with the addition of Fe₃ O₄ increased its catalytic and applicative potential.