Highly Efficient Enzymatic Catalytic Transformation for the Synthesis of Rare Ginsenoside Compound K (CK) and Its Bioactivity Study

As a principal metabolite of ginsenosides, compound K (CK) exhibits remarkable antioxidant, anti-inflammatory, antidiabetic, and anticancer bioactivities. However, CK is naturally scarce in ginseng and its industrial application is limited by the lack of efficient deglycosylating enzymes for large-scale CK bioproduction. Here, we report a synthetic biology-driven approach for high-yield CK production via recombinant β-glycosidase-mediated bioconversion of the polar ginsenoside Rb1. The β‑glycosidase-encoding gene was introduced into Escherichia coli BL21 (DE3), and the resulting engineered strain produced 2.1 g/L β‑glycosidase in shake flasks and 10.1 g/L in a 5-L fermentor. The crude β-glycosidase exhibited excellent enzymatic activity; at a concentration of 1.5 g/L, it converted 95% of the Rb1 substrate (initial concentration 10 g/L) to CK within 4 h. In vitro studies demonstrated CK's high cytocompatibility and potent anti-aging effects, including suppression of reactive oxygen species (via upregulation of superoxide dismutase, catalase, and glutathione peroxidase), enhanced collagen I, Ⅲ and elastin synthesis, and matrix metalloproteinase-1 inhibition. These findings highlight CK as a promising candidate for anti-wrinkle formulations, supported by the feasibility of scalable bioproduction.