Abstract
Wild ginseng (W-GS), ginseng under forest (F-GS, planted in mountain forest and growing in natural environment), and cultivated ginseng (C-GS) were compared via HPLC-DAD and HPLC-IT-TOF-MS(n). A total of 199 saponins, including 16 potential new compounds, were tentatively identified from 100 mg W-GS (177 saponins in W-GS with 11 new compounds), F-GS (56 saponins with 1 new compound), and C-GS (60 saponins with 6 new compounds). There were 21 saponins detected from all the W-GS, F-GS, and C-GS. Fifty saponins were only detected from W-GS, including 23 saponins found in ginseng for the first time. Contents of ginsenosides Re (12.36-13.91 mg/g), Rh(1) (7.46-7.65 mg/g), Rd (12.94-12.98 mg/g), and the total contents (50.52-55.51 mg/g) of Rg(1), Re, Rf, Rb(1), Rg(2), Rh(1), and Rd in W-GS were remarkably higher than those in F-GS (Re 1.22-3.50 mg/g, Rh(1) 0.15-1.49 mg/g, Rd 0.19-1.49 mg/g, total 5.69-18.74 mg/g), and C-GS (Re 0.30-3.45 mg/g, Rh(1) 0.05-3.42 mg/g, Rd 0.17-1.68 mg/g, total 2.99-19.55 mg/g). Contents of Re and Rf were significantly higher in F-GS than those in C-GS (p < 0.05). Using the contents of Re, Rf, or Rb(1), approximately a half number of cultivated ginseng samples could be identified from ginseng under forest. Contents of Rg(1), Re, Rg(2), Rh(1), as well as the total contents of the seven ginsenosides were highest in ginseng older than 15 years, middle-high in ginseng between 10 to 15 years old, and lowest in ginseng younger than 10 years. Contents of Rg(1), Re, Rf, Rb(1), Rg(2), and the total of seven ginsenosides were significantly related to the growing ages of ginseng (p < 0.10). Similarities of chromatographic fingerprints to W-GS were significantly higher (p < 0.05) for F-GS (median: 0.824) than C-GS (median: 0.745). A characteristic peak pattern in fingerprint was also discovered for distinguishing three types of ginseng. Conclusively, wild ginseng was remarkably superior to ginseng under forest and cultivated ginseng, with ginseng under forest slightly closer to wild ginseng than cultivated ginseng. The differences among wild ginseng, ginseng under forest, and cultivated ginseng in saponin compositions and contents of ginsenosides were mainly attributed to their growing ages.