Ginseng glycopeptides from Panax ginseng: Process optimization, structural characteristics, and immunomodulatory activities.

An efficient enzymatic hydrolysis process for preparing ginseng glycopeptides was optimized using response surface methodology (RSM). Under the optimal conditions (substrate 13%, enzyme 6469 U/g, 49 °C, pH 8.1, 6 h), the degree of hydrolysis reached 49.49%. The purified ginseng glycopeptide (PGG) was homogeneous with a molecular weight of 57.829 kDa, rich in galactose (Gal), arabinose (Ara), arginine (Arg) and phenylalanine (Phe), and featured an O-glycosidic linkage. In cyclophosphamide-induced immunosuppressed mice, PGG, ginseng water extract (GWE), total ginsenoside complex (TGC), and ginseng glycopeptide complex (GGC) restored immune functions to varying extents. Notably, PGG showed marked effects in enhancing phagocytosis, splenocyte proliferation, delayed-type hypersensitivity, serum hemolysin levels and TNF-α expression. This study provides a feasible preparation method for ginseng glycopeptides and offers new insights into their multi-component, multi-target immunomodulatory mechanisms, supporting their potential as novel glycopeptide-based immunomodulators.