BSA-templated magnetic nanocomposite Ni-MOF for one step purification and co-immobilization of glycosyltransferases and sucrose synthase catalyzing ginsenoside Rh2 transformation

Ginsenoside Rh2 is a rare but pharmacologically potent component of ginseng, which is known for its immunomodulatory, anti-tumor, and antiaging effects. However, its low natural abundance and the instability of free enzymes used in its biosynthesis hinder large scale production. To address these challenges, a magnetic nanocomposite nickel-based metal organic framework (Ni-MOF) via a mild, bovine serum albumin (BSA)-templated synthesis method was developed. This MOF was engineered to enable simultaneous purification and co-immobilization of recombinant glycosyltransferase (UGT) and sucrose synthase (SUSy), forming a dual-enzyme catalyst system BSA-Trypsin-Fe 3 O 4 /MOF@UGT&SUSy BT-Fe 3 O 4 /MOF@UGT&SUSy for the biotransformation of ginsenoside Rh2. The immobilized enzyme system BSA-Trypsin-Fe 3 O 4 /MOF (BT-Fe 3 O 4 /MOF) demonstrated high enzyme loading 176.39 mg/g and enhanced thermal, pH, and storage stability compared to free enzymes. The co-immobilized UGT-SUSy system also facilitated in situ regeneration of UDP-glucose, significantly improving catalytic efficiency. Under optimized conditions, the system achieved a Rh2 yield of 80.67 μg/mL and retained 58.01 % of the initial activity after 12 repeated cycles. This work not only highlights the potential of BT-Fe 3 O 4 /MOF in sustainable and efficient enzymatic catalysis but also offers a sustainable and scalable approach for the enzymatic synthesis of high-value nutraceuticals.