Multivariate Statistical Evaluation of Ginseng Quality and Antioxidant Activity

The composition of ginsenosides is closely associated with antioxidant activity, but the effects of variety and growth year on the accumulation of individual ginsenosides and their quantitative relationships with free radical scavenging activity remain unclear. In this study, six ginsenosides (Rb1, Rb2, Rc, Rd, Re, and Rg1) in cultivated ginseng (Panax ginseng C. A. Mey.) and American ginseng (Panax quinquefolius L.) were quantified by HPLC, combined with DPPH and ABTS assays, and systematically analyzed using PCA, OPLS-DA, HCA, and PLSR. The results showed that variety exerted a much greater influence than growth year. American ginseng contained significantly higher levels of PPD-type ginsenosides (Rb1, Rd, Rc), while Rg1 was more abundant in cultivated ginseng. OPLS-DA clearly distinguished the two varieties based on ginsenoside profiles, with Rc, Rb1, and Rd identified as key marker ginsenosides (VIP > 1). Ginsenoside extracts showed scavenging abilities against both DPPH and ABTS. However, the PLSR model only successfully yielded predictive capability for DPPH. The poor prediction for ABTS suggested that ABTS scavenging may be attributed to other untested constituents in the extracts. This study provides a robust basis for variety-oriented quality control and antioxidant efficacy evaluation in ginseng products.