Immobilization of Protease KHB3 onto Magnetic Metal–Organic Frameworks and Investigation of Its Biotechnological Applications

Recently, enzyme immobilization via self-assembly of magnetic metal–organic frameworks (mMOFs) has attracted attention for researchers. In this study, a Bacillus protease KHB3 was embedded into a magnetic metal organic framework. Temperature activity results shown that the free protease displayed the optimal activity at 40 °C, while the immobilized protease showed the highest activity at 60 °C. Besides, a 20% improvement in the activity of the immobilized form was found at 80 °C against the free protease. Furthermore, the Vmax of immobilized enzyme was 1.75 fold more than the free enzyme. Results exhibited that the immobilized protease showed 1.54 and 1.55 folds more activity than the control toward fibrin and gelatin, respectively. The immobilized protease reserved about twofold higher activity than the free protease after 21 days of storage. Results revealed that the immobilized enzyme showed 38% clot lysis, while the free protease showed 26% at a similar condition. The hydrolysis degree of the free protease and immobilized protease was obtained about 17 and 45% after 8 h incubation at 50 °C, respectively. Overall, our results show the high potential of these enzymes in the clot lysis capacity and construction of high-value compounds from protein hydrolysis of shrimp protein waste.