Preparation of Expoxy-Functionalized Magnetic Nanoparticles for Immobilization of Glycerol Dehydrogenase

Abstract

Immobilization of glycerol dehydrogenase (GDH) from Serratia marcescens H30 onto epoxy functional magnetic nanoparticles by covalent attachment was carried out. The optimal immobilization conditions were obtained as follows: enzyme/support 6.08 mg/g, temperature 25 °C, pH 7.0 and time 8 h. Under these conditions, a high immobilization yield above 90% was obtained. The characterization of the immobilized GDH indicated that enhanced pH and thermal stability were achieved. Kinetic parameters Km of free and immobilized GDH were determined as 10.35 mM and 15.76 mM, respectively. The immobilized GDH retained about 85% initial activity after ten cycles. These results suggested that GDH immobilized onto magnetic nanoparticles is a simple and efficient way for preparation of stable enzyme. And the immobilized GDH has potential applications in the production of DHA.

Recent Developments in Carriers and Non-Aqueous Solvents for Enzyme Immobilization

“…Numerous covalent bond-based methods have been directly used in nanomaterials recently [44,45]. These nanomaterials can be tailored to the target enzyme, and their large surface area and selectivity of porosity provide great advantages in industrial and pharmaceutical products [6,[46][47][48]. For example, immobilization of urease on epichlorohydrin cross-linked carboxymethyl cellulose beads with polyacrylamide resulted in both the optimum pH and temperature shifting higher to 8 and 45 • C, respectively, and enabled 88% of the enzyme activity to be maintained after 10 cycles, and the modified support helped improve the stability of the urease structure [49].…”

Cloning, Expression and Characterization of a Highly Active Alcohol Dehydrogenase for Production of Ethyl (S)-4-Chloro-3-Hydroxybutyrate

“…When the temperature was raised to 55°C, the enzyme activity was around 76% of the initial activity. The possible reason for the decreased relative activity is that the spatial structure change of the enzyme at high temperature [22]. Several short-chain dehydrogenases including carbonyl reductase and alcohol dehydrogenase could catalyze conversion of COBE to (S)-CHBE.…”

Combined Cross-Linked Enzyme Aggregates as Biocatalysts

“…Moreover, combi-CLEAs showed the highest thermal stability at 55 °C and 75 °C. As immobilized enzymes, the combi-CLEAs have a more evident protection from thermal denaturation and require much more energy to break down the active conformation [38,109].…”

“…The reason for a higher rate of starch conversion was that increased proximity of enzymes and reduced the diffusion limitation of the substrate from one enzyme to another by using combi-CLEAs. Moreover, combi-CLEAs showed the highest thermal stability at 55 • C and 75 • C. As immobilized enzymes, the combi-CLEAs have a more evident protection from thermal denaturation and require much more energy to break down the active conformation [38,109]. chemical method, the combi-CLEAs mediated synthesis of mandelic acid has significant advantages such as having fewer unit operations, a smaller reactor volume and solvent, less waste generation, good stereo-selectivity, and it is less time-consuming [11,102].…”