Authors: Henriques, RO; Bork, JA; Fernandez-Lorente, G; Guisan, JM; Furigo, A; de Oliveira, D; Pessela, BC
Mol. Catal.. vol: 453. page: 2468-8231.
Date: JUL. 2018.
This article describes a model for co-immobilization of multiple enzymes onto a magnetic support. Lipase from Thermomyces lanuenosus (TLL) and beta-D-galactosidase from Kluyveromyces lactis (beta Gal) were selected for this study. TLL was immobilized onto hydrophobic magnetic nanoparticles from magnetite (Fe3O4) by a physical adsorption mechanism and was modified by chemical amination of surface carboxylic groups with ethylenediamine using a 1-ethyl-3-(dimethylaminopropyl) carbodiimide coupling method. The enzymatic derivate containing the adsorbed lipase had a 5 fold factor hyperactivation after the immobilization, and the residual activity decreased by 40% after chemical amination. beta Gal was co-immobilized on the aminated derivate by ion exchange. The post-treatment of the co-immobilized derivate with each of the cross-linking agents (glutaraldehyde and aldehyde-dextran) was studied to improve the stability of the enzymes. The derivates showed a better thermal stability than the enzymes in their free form (50 degrees C for TLL and 30 degrees C for beta Gal), increasing their thermal stabilities, and allowing their use over a wide pH range and up to 50 degrees C for beta Gal and up to 70 degrees C after the cross-linking step..