Abstract
Enzymes have a wide variety of applications in diverse biotechnological fields, and the immobilization of enzymes plays a key role in academic research or industrialization due to the stabilization and recyclability it confers. In this study, we immobilized the Brassica oleracea chlorophyllase 1 (BoCLH1) or Candida rugosa lipase (CRL) in magnetic iron oxide nanoparticles-loaded alginate composite beads. The catalytic activity and specific activity of the BoCLH1 and CRL entrapped in magnetic alginate composite beads were evaluated. Results show that the activity of immobilized BoCLH1 in magnetic alginate composite beads (3.36 ± 0.469 U/g gel) was higher than that of immobilized BoCLH1 in alginate beads (2.96 ± 0.264 U/g gel). In addition, the specific activity of BoCLH1 beads (10.90 ± 1.521 U/mg protein) was higher than that immobilized BoCLH1 in alginate beads (8.52 ± 0.758 U/mg protein). In contrast, the immobilized CRL in magnetic alginate composite beads exhibited a lower enzyme activity (11.81 ± 0.618) than CRL immobilized in alginate beads (94.83 ± 7.929), and the specific activity of immobilized CRL entrapped in magnetic alginate composite beads (1.99 ± 0.104) was lower than immobilized lipase in alginate beads (15.01 ± 1.255). A study of the degradation of magnetic alginate composite beads immersed in acidic solution (pH 3) shows that the magnetic alginate composite beads remain intact in acidic solution for at least 6 h, indicating the maintenance of the enzyme catalytic effect in low-pH environment. Finally, the enzyme immobilized magnetic alginate composite beads could be collected by an external magnet and reused for at least six cycles.
Highlights
Despite the wide variety of applications of enzymes in diverse biotechnological fields, the utilization of their free forms are usually not cost-effective, because in general the enzymes were not recyclable after the catalytic reaction, and are not suitable to be used in industrial or mass catalysis processes [1–3]
Both the magnetic iron oxide nanoparticles (MIO NPs) and Brassica oleracea chlorophyllase 1 (BoCLH1) are loaded in the same beads
The results show that the MIO NP-entrapped alginate beads remained intact in acidic solution for at least 6 h
Summary
Despite the wide variety of applications of enzymes in diverse biotechnological fields, the utilization of their free forms are usually not cost-effective, because in general the enzymes were not recyclable after the catalytic reaction, and are not suitable to be used in industrial or mass catalysis processes [1–3]. A key topic for industrialization by stabilizing enzymes and making them recyclable, is one of the feasible approaches that can overcome the abovementioned limitations [4,5]. Due to the possible loss of enzyme activity during the immobilization, preserving the activity of the immobilized enzyme becomes quite an important issue [1]. Compared with other immobilization methods, enzyme encapsulation (i.e., the enzyme is entrapped in the internal structure of a polymer) possesses several advantages such as higher preservation of catalytic activity, better mobility that can enhance the enantioselectivity, and improved thermal stability and operational stability that result in higher catalytic conversions [4]. Entrapping the enzymes in gels has some drawbacks, including potential diffusion limitations related to the substrate reaching the enzyme
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
