Updating chemical profiling of red ginseng via the elucidation of two geometric isomers of ginsenosides Rg9 and Rg10

With the increasing popularity of dietary supplements, the quantitative analysis and quality control of their constituents have emerged as a significant regulatory and safety challenge. Ginseng, the root of Panax ginseng, has been used as a folk medicine to improve immunity, provide nutrition and diminish fatigue. Steam-processed ginseng, commonly called “red ginseng” in Korea and China, is prevalent as a dietary supplement. The different processing methods for the production of ginseng products could lead to quantitative and qualitative variations in biologically active compounds, such as the ginsenosides, present in the products. Herein, we have verified that ginsenoside Rf was transformed into two geometric isomers of ginsenoside Rg9, e.g., (20E)- and (20Z)-ginsenosides Rg9, and another ginsenoside here designated Rg10, which was inappropriately reported as ginsenoside Rg8 in a previous study. This study could be of practical use in the establishment of a comprehensive chemical profile of red ginseng for the quality control and standardization of commercial dietary supplements.