Differences in metabolites and ginsenoside contents of wild-simulated ginseng according to harvest time

Wild-simulated ginseng ( Panax ginseng C.A. Meyer, WSG), a member of the Araliaceae family, is cultivated in natural mountainous forests without artificial facilities or chemicals. The metabolic composition of WSG varies with the environment and harvest timing as environmental conditions affect WSG. Therefore, this study aimed to investigate the harvest-time-dependent variations in the metabolic and ginsenoside profiles of WSG using NMR, GC/MS, and LC/MS. Aerial and root samples were collected monthly from May to September. Multivariate analyses showed that the metabolic patterns differed with harvest time and plant part. The sugar levels, especially those of glucose, fructose, and xylose, were higher in the aerial parts in May, whereas the organic acid and sucrose levels increased in the roots over time. Among the identified 22 ginsenosides, Rd, Rg3(S), and F1 predominantly accumulated in the aerial parts, while Rb1, Rc, and Ro predominated in the root parts. The ginsenoside content was the highest when combining the aerial and root parts. The levels of sugars (glucose, xylose, and sucrose) and those of ginsenosides were strongly and positively correlated, suggesting carbon metabolism is essential in ginsenoside biosynthesis. This study revealed that the metabolite and ginsenoside levels depend on harvest time of WSG, providing a basis for optimal harvest timing and functional applications.