Magnetic Casein Aggregates As an Innovative Support Platform for Laccase Immobilization and Bioremoval of Crystal Violet Publisher Pubmed



Hariri P¹ ; Jafarinodoushan H¹ ; Mojtabavi S¹ ; Hadizadeh N¹ ; Rezayaraghi F¹ ; Faramarzi MA¹
Source: International Journal of Biological Macromolecules Published:2022

Abstract

In this study, casein@CoFe2O4 was fabricated through a green synthesis methodology and applied to immobilize laccase. The constructed casein@CoFe2O4 exhibited porous structures with distinct cavities and suitable magnetic properties. The abundance of aromatic functional groups on the surface renneted casein and possible π-type interaction between laccase and para-κ-casein resulted in a successful immobilization. The biocatalyst retained 50% of its initial activity after 24 reusability cycles, indicating stable immobilization of laccase onto the casein microstructures. The stability of laccase after immobilization was improved by 300% in comparison with the free enzyme, especially in basic pH values. The constructed laccase@casein@CoFe2O4 was then incorporated to remove crystal violet (CV) as an environmentally harmful synthetic tri-phenylmethane dye. The prepared heterogeneous biocatalyst effectively diminished the antimicrobial activity of CV up to 81.3% in 40 min against some bacterial strains, resulting from the formation of more minor toxic metabolites identified by liquid chromatography coupled with mass spectroscopy after degradation procedure. The proposed green and feasible method for the preparation of magnetic casein aggregates has not been previously reported. The incorporation of casein, which acted as a molecular chaperon, resulted in a significant improvement in the enzymatic stability and exhibited appropriate reusability for the constructed biocatalytic system. © 2022 Elsevier B.V.