Abstract
Enzyme preparation can protect the enzyme conformation in storage, transportation, and operation process, but excessive additives can affect enzyme performance. In this work, a Ca2+-based metal-organic framework (UTSA-280) was prepared to encapsulate amylases (α-amylase, pullulanase, and glucoamylase) in situ. After release from UTSA-280, the relative activity of α-amylase and pullulanase increased to 177.8 and 201.0%, respectively, as compared to pure enzymes. Mechanism explorations indicate that amylase released from UTSA-280 has more Ca2+ on its surface with stronger combination, which probably leads to the activation effect to metal ion activating enzyme. Besides, UTSA-280 could protect enzymes from heat, organic solvent, and trypsin, which is beneficial for the storage, transportation, and operation of enzyme. Therefore, it is concluded that metal-organic frameworks could be a promising metal ion activating enzyme preparation material with activity promoting and protective effects.