Application of a carveol dehydrogenase from Klebsiella sp. O852 immobilized on magnetic gel for carvone production

Abstract

In this study, magnetic gel-embedded immobilized carveol dehydrogenase (Fe₃O₄@Gel@PEI@KlebADH1) was prepared and characterized by fourier transform infrared spectroscopy, scanning electron microscopy and vibrating sample magnetometer. The thermal and pH stabilities, storage stability, and kinetic parameters of Fe₃O₄@Gel@PEI@KlebADH1 compared to that of free KlebADH1 were investigated. Obtained results revealed that the Fe₃O₄@Gel@PEI@KlebADH1 exhibited enhanced stability and catalytic activity, with a superior thermal stability and broader pH range compared to free KlebADH1. After 8 days of storage, immobilized KlebADH1 still retained 69.60 % and 50.37 % of its initial activity at 4 °C and 30 °C, respectively, whereas free KlebADH1 merely retained 17.18 % and 1.97 % of its initial activity. Additionally, after 5 cycles of reuse, Fe₃O₄@Gel@PEI@KlebADH1 still maintained over 60 % of its initial activity, indicating its high reusability. Furthermore, carvone was produced using the Fe₃O₄@Gel@PEI@KlebADH1 as catalyst, and after optimization, the carvone yield reached 8.91 mM using 90 μg/mL Fe₃O₄@Gel@PEI@KlebADH1, 12 mM carveol and 2 mM NADP⁺at 40 °C for 12 h This study identified the potential applications of magnetic gel-embedded immobilized KlebADH1 for the production of carvone.