The Synthesis of Ginsenoside Compound K Using a Surface-Displayed β-Glycosidase Whole-Cell Catalyst

Ginsenoside compound K (CK) has garnered considerable attention due to its versatile pharmacological properties, including anti-inflammatory, anti-allergic, anti-aging, anti-diabetic, and hepatoprotective effects, along with neuroprotection. The conventional approach to synthesizing ginsenoside CK involves enzymatic conversion. However, the purification of enzymes necessitates effort and expense, and enzymes are prone to inactivation. Additionally, whole-cell catalysis suffers from inefficiency due to limited cell permeability. To address these challenges, we harnessed the YiaT protein as an anchoring motif, establishing a surface display system for β-glycosidase Bgp3. This innovative system served as a whole-cell catalyst for the efficient synthesis of ginsenoside CK. We further optimized the YiaT-Bgp3 system, enhancing display levels and significantly increasing ginsenoside CK production. Optimal conditions were achieved at an IPTG concentration of 0.5 mM, an induction temperature of 16 °C, a ginsenoside substrate concentration of 15 mg/mL, and a catalytic temperature of 30 °C. Ultimately, the YiaT-Bgp3 system synthesized 5.18 ± 0.08 mg/mL ginsenoside CK within 24 h, with a conversion of 81.83 ± 1.34%. Furthermore, the YiaT-Bgp3 system exhibited good reusability, adding to its practicality and value. This study has successfully developed an efficient whole-cell Bgp3 biocatalyst, offering a convenient, highly productive, and economically viable solution for the industrial production of ginsenoside CK.