Construction of a hollow MOF with high sedimentation performance and co-immobilization of multiple-enzymes for preparing rare ginsenoside CK

Abstract

Good catalytic performance and cycling stability are essential guarantees for the industrial application of immobilized enzymes. The protein-induced soft template method was used to prepare the large-sized snailase&β-glucosidase@hollow-Cu-H₂BDC (Sna&β-G@H-Cu-BDC) biocomposite for the production of the rare ginsenoside compound K (CK). The special synthesis process of the Cu-BDC Metal organic framework (MOF) and the formation of stable Cu–O coordination bonds facilitated the preparation of the Sna&β-G@H-Cu-BDC biocomposite with larger size and good stability. The excellent physical protection for the enzyme was provided by the hollow structure, and the conformational freedom of the enzyme was preserved effectively. Meanwhile, adequate water can be held in the hollow MOF during conversion, which is conducive to the catalytic action of the enzyme. In addition, dual enzyme cascade catalysis efficiently improved the preparation of the rare ginsenoside CK. The CK yield of the Sna&β-G@H-Cu-BDC biocomposite reached 67.5%, and the enzyme activity after six cycles remained at 50% of the initial enzyme activity. Furthermore, the recovery rate of the Sna&β-G@H-Cu-BDC biocomposite with good sedimentation performance reached 82.14% after settling for 60 min. This eco-friendly, straightforward, and sustainable strategy provides a good theoretical support for the industrial production of the rare ginsenoside CK.