Three-dimensional magnetic enzyme-inorganic hybrid nanocomplexes with high reusability and stability to obtain lactose-free products

Multitudinous people suffer from lactose intolerance which is bound up with lactose malabsorption. Enzymatic hydrolysis is the most common approach for the preparation of lactose-free products. The recycling of hydrolytic enzymes is an effective way to produce low-cost lactose-free products. Herein, a facile strategy for the preparation of the novel Fe3O4 magnetic nanoparticles-β-galactosidase-CaHPO4 hybrid nanocomplexes (β-gal MNCs) was established. β-gal MNCs were composed of amino-modified Fe3O4 magnetic nanoparticles, β-galactosidase and crystalline calcium hydrogen phosphates. Meanwhile, under the external magnetic field, the magnetic β-gal MNCs can be easily and rapidly separated from the reaction medium. In addition, the β-galactosidase maintained most of its initial activity after immobilization into the β-gal MNCs. In a continuous hydrolysis reaction, β-gal MNCs exhibited excellent reusability and good stability. Therefore, β-gal MNCs hold promising prospects in the fast and low-cost preparation of lactose-free milk.