Saponins composition in American ginseng leaf and berry assayed by high-performance liquid chromatography

The root of American ginseng is a commonly used herbal medicine in the United States. However, the compositions of American ginseng leaves and berries are not clear to date. In this study, we improved a method for the analysis of 12 ginsenosides based on solid phase extraction and high-performance liquid chromatography-ultraviolet. Good resolution was obtained for all tested ginsenosides: Rb1, Rb2, Rb3, Rc, Rd, Re, Rg1, Rg2, 20(R)-Rg2, Rg3, Rh1, and Rh2. Ginsenosides Rh1, Rg2, and 20(R)-Rg2 were easily separated with this column. The modified gradient elution program resulted in satisfactory linearity and precision. Solid phase extraction made the analysis accurate and efficient. Other investigators recently observed that ginsenoside Rb3 is a potent neuroprotective compound; it can promote learning and memory. In this report, we found that the major ginsenoside in American ginseng leaves and berries was ginsenoside Rb3, while Rb3 only had limited amounts in the root of American ginseng and other species of the Panax genus. Ginsenoside Rb3 was quantified as 4.71% in American ginseng leaves and 5.35% in berries, suggesting that American ginseng leaves and berries are new sources of ginsenoside Rb3.