Application of magnetic field (MF) as an effective method to improve the activity of immobilized Candida antarctica lipase B (CALB)

Immobilization is considered a key condition for enzyme applications in the chemical industry. However, immobilization may damage the structure and charge state of an enzyme or increase steric hindrance, leading to a decrease in its catalytic effect. Recently, applying an external magnetic field (MF) was found to be able to change the structure of enzymes and even enhance their catalytic activity, which could reduce or neutralize the damage caused by immobilization. In this study, the effect of MF on the immobilization of Candida antarctica lipase B (CALB) was systematically explored. Specifically, the optimal MF treatment was obtained based on the experimental design, while the properties of the immobilized enzyme were analyzed according to the thermodynamic and kinetic parameters of the reaction. The results obtained in the study revealed that MF could positively alter the activity of immobilized CALB, and the best effect was obtained at 0.175 T, while the activity was 2 times the original immobilized enzyme activity. Notably, the catalytic efficiency and substrate affinity of the magnetic-immobilized enzyme (0.175 T) were all improved, and high stability and reusability were exhibited as well. Additionally, changes in the enzymatic structure and activity with MF in experiments were explained by a protein landscape model. This study provides a unique idea for the application of MF in the field of biochemistry, which may demonstrate even greater potential for improving potency in the biochemical industry.