Post-harvest treatment of wild-simulated ginseng under climate-smart environmental conditions

PLOS One | https://doi.org/10.1371/journal.pone.0326237 June 18, 2025 3 / 6 Korea)—the first certified organic ginseng cultivation medium in Korea (Certification No. 1-2-109)—as the post-harvest treatment medium. Further details on cultivation techniques, environmental management, and container design are pro- vided in S1 Appendix. Ginsenoside analysis We analysed nine major ginsenosides (Rb1, Rg1, Rg3, Rd, Re, Rf, Mc1, F2, and Compound K) using the Waters ACQUITY® ultra-performance liquid chromatography (UPLC) system (Waters Corp., Milford, MA, USA). We operated the instrument at a gas temperature of 300 °C and a flow rate of 5 L/min. The nebulizer pressure was maintained at 45 psi, while the sheath gas temperature and flow rate were set at 250 °C and 11 L/min, respectively. Both positive and negative modes were employed, with a capillary voltage of 3,500 V and a nozzle voltage of 500 V. To ensure consistency with pre- vious studies and eliminate moisture-related variations, we used dried post-treated WSG samples for all analyses, allow- ing direct comparison with existing data on both WSG and FCG. Impact of post-treatment protocol on WSG growth and survival characteristics To evaluate post-treated WSG growth patterns, we monitored root weight changes over five months. Specimens were initially subjected to visual screening for preliminary separation, then weighed to assign them into two groups based on a 1.0 g fresh weight threshold: Group A (> 1.0 g; mean: 1.58 ± 0.21 g) and Group B (≤ 1.0 g; mean: 0.74 ± 0.18 g). This group-

ing criterion was informed by a bimodal weight distribution observed across 220 specimens (Fig 1A). The final harvest at five months revealed substantial growth in both groups: Group A achieved an average root weight of 3.85 g (a 2.44-fold increase), whereas Group B reached an average of 1.53 g (a 2.07-fold increase) (Fig 1B). To evaluate the effect of post-treatment on the ginsenoside profiles of WSG, UPLC analysis was performed. The total ginsenoside content of post-treated WSG was 10.458 mg/g of dried wild-simulated ginseng (DG) weight and considering an average root weight of 4.0 g, each root contained approximately 41.83 mg of total ginsenosides (Table 1). Of the anal- ysed ginsenosides, Re was the most abundant (7.716 mg/g DG), followed by Rb1 (1.293 mg/g DG) and Rg1 (1.195 mg/g Fig 1. Post-harvest treatment of wild-simulated ginseng (WSG). (A) Smart facility for post-treated WSG at Pyeongchang campus in Seoul National University. (B) Changes in average root weight of post-treated WSG over the treatment period. Group A (initial n = 220) and Group B (initial n = 220) rep- resent larger and smaller roots, respectively. Samples (n = 40) were excluded at 2 months to measure the ratio of underground to shoot fresh weight. The survival rate was 96.8% for Group A and 97.3% for Group B. *** represents p value < 0.0001 (t test; FDR adjusted). https://doi.org/10.1371/journal.pone.0326237.g001