Stable and efficient immobilization technique of aldolase under consecutive microwave irradiation at low temperature

To establish a stable and efficient immobilization technique under microwave irradiation, a focused microwave reaction system was used, where the temperature was set appropriately in the microwave system and cooling module to produce consecutive microwave irradiation. 2-Deoxy-D-ribose-5-phosphate aldolase (DERA) was rapidly and efficiently immobilized in mesocellular siliceous foams (MCFs) under microwave irradiation. When the output power in the microwave system was set to 30 W, after 3 min, 88.4% of the enzyme protein was coupled to the wall of the support pores and the specific activity of the immobilized enzyme was 2.24 U mg−1, 149.2% higher than that of the free enzyme and 157.0% higher than that of the non-microwave-assisted immobilized enzyme. In catalysis, microwave-assisted immobilized DERA tolerated a wider range of both pH and temperature than other DERA preparations. The thermal and storage stabilities were also significantly improved. This focused; microwave-assisted immobilization technique has proven to be simple, stable and highly efficient. This technique could also be applied to other enzyme immobilizations.

Research highlights
► Focus microwave system gives the stable irradiation in the enzyme immobilization.
► Micorwave irradiation accellerated the covalent immobilization of 2-deoxy-D-ribose-5-phosphate aldolase (DERA) and improved its activity significantly.
► The immobilized DERA under suitable microwave irradiation exihibited better thermal and storage stability.