[Plant metabolomics approach for age discrimination of mountain cultivated ginseng using UPLC-Q-TOF/MS]

Growth year is one of the important factors for the quality of mountain cultivated ginseng (MCG). For age differentiation of MCG, rhizome extracts of ginseng aged from 11 to 15 years were analyzed using a non-targeted approach with ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS)-based on plant metabolomics technique. Multivariate statistical methods such as principal component analysis (PCA) and orthogonal partial least squared discrimination analysis (OPLS-DA) were used to compare the derived patterns among the samples. The results showed that the chemical constituents of MCG rhizome extracts of ginseng aged from 11 to 15 years were different. The data set was subsequently applied to metabolite selection by variable importance in the projection (VIP) for sophisticated classification with the optimal number of metabolites. The OPLS-DA model of MCG has a high interpretability and predictive capability, which established by selecting metabolites of MCG aged from 11 to 15 years. By this approach, MCG samples aged from 11 to 15 years, which are the most in demand in the Chinese ginseng market, can be precisely differentiated on the basis of selected metabolites. This proposed analytical method is fast, accurate, and reliable for discriminating the growth year of MCG. Moreover, this study supplies a new method for the age discrimination of other Chinese medicinal materials.