Seasonal and Root-Specific Metabolomic Profiles of Panax Ginseng Meyer by Ultra-High Performance Liquid Chromatography-Quadrupole-Time-of-Flight-Mass Spectrometry (UPLC-QTOF-MS) and Partial Least Squares-Discriminant Analysis (PLS-DA)

The chemical composition of ginseng varies by several factors such as age, harvest season, and region. Each part of fresh ginseng contains certain valuable bioactive compounds; however, chemical studies of ginseng have focused on the ginsenoside content. In this study, we examine the chemical composition of Panax ginseng Meyer as related to harvest season and specific root parts via untargeted metabolomics using ultra-high performance liquid chromatography-quadrupole-time-of-flight-mass spectrometry (UPLC-QTOF-MS). Multivariate statistical analysis such as partial least squares discriminant analysis (PLS-DA) was used to select significant metabolites distinguishing ginseng harvested in different seasons and various ginseng parts. The selected thirteen metabolites were identified as amino acids, ginsenosides, and fatty acid amides through MS fragment pattern analysis. Additional chemometric analysis revealed chemical consistency between main and fine roots regardless of harvest time, indicating a stable chemical composition in P. ginseng among seasons. Furthermore, most ginsenosides among the thirteen selected metabolites had higher abundance in fine roots than in main roots, while primary metabolites were more abundant in main roots, highlighting a unique chemical composition dependent on the specific root parts.