Glycosidase-Driven Bioprocess for Production of Rare Ginsenosides from Underutilized Ginseng Stem-Leaf

Ginseng stem-leaf biomass represents an abundant yet underutilized agricultural residue rich in valuable ginsenosides. Herein, an integrated glycosidase-driven bioprocess was developed for the efficient and selective preparation of rare ginsenosides from this low-cost feedstock. Seven highly specific glycosidases were screened and strategically combined to achieve site-specific deglycosylation, thereby systematically converting seven major ginsenosides into 17 target rare ginsenosides. An enzyme-mediated separation strategy was designed to resolve overlapping congeners, yielding high-purity monomers (>90%). Using lower-cost ginsenosides as substrates, the optimized biocatalytic protocols generated ten distinct product mixtures, each enriched in a specific rare ginsenoside. Furthermore, a three-step purification process consisting of centrifugation, ethanol extraction, and recrystallization or resin adsorption was established, with recrystallization showing superior performance. This production platform was successfully implemented using both ginseng stem-leaf biomass and root materials as feedstocks, and different product specifications could be readily tailored by adjusting glycosidase combinations and ratios. This work provides an integrated enzymatic strategy for valorizing ginseng agricultural residues into high-value rare ginsenosides, offering an efficient enzymatic route for biomanufacturing and purification.