Light Intensity and Gibberellic Acid Differentially Shape Primary Metabolism and Ginsenoside Profiles in Panax ginseng Sprouts

Ginseng sprouts (Panax ginseng C.A. Meyer) are mostly cultivated under controlled indoor conditions, allowing modulation of growth and phytochemical composition through environmental and hormonal treatments. In this study, 1H NMR and UPLC-QTOF/MS were used to investigate the independent and interactive effects of light intensity and gibberellic acid (GA3) on primary metabolism and ginsenoside profiles. While GA3 promoted shoot growth, high light reduced plant height but increased root dry weight. Multivariate analysis of 42 identified primary metabolites and 26 ginsenosides revealed that the primary metabolite profiles are primarily distinguished by GA3, whereas ginsenoside profiles are more clearly differentiated based on light intensity. GA3 broadly increased soluble carbohydrates and decreased free amino acids, whereas light intensity had a selective effect on some primary metabolites. In contrast to the limited interaction effects in primary metabolism, significant interactions between light and GA3 were detected for eight ginsenosides. High-intensity light increased the content of several ginsenosides, including Re, Rg1, Rd, Rb2, and Rc, while decreasing protopanaxadiol (PPD)-type ginsenosides that lack a sophorosyl moiety at C-3. Correlation analysis across the experimental conditions revealed coordinated variation between primary metabolites and ginsenosides, with the most prominent pattern corresponding to the light-response axis. Overall, GA3 and light intensity exerted distinct but interconnected effects across metabolic layers, providing a framework for understanding how cultivation factors determine growth and phytochemical composition in ginseng sprouts.