Effects of Drying Methods on Morphological Characteristics, Metabolite Content, and Antioxidant Capacity of .

is a rare and endangered medicinal herb in China and a typical medicinal and food plant. Most of the research related to focuses on its pharmacological effects, artificial cultivation and clinical applications. However, there are few comprehensive evaluations on the quality of under different drying methods. In this study, the effects of vacuum freeze-drying (DG), oven-drying (HG) and air-drying (YG) on the morphological characteristics, microstructure, antioxidant activity and metabolites of were investigated using wild as the research object. The results showed that in their appearance and morphology, the YG- and HG-method samples were darker in color and wilted, while the DG- method samples were golden yellow in color and had better fullness. In terms of microstructure, the stomata of the YG and HG method samples were relatively small and irregularly shaped, whereas those of the DG method samples were larger and neat. In terms of antioxidant capacity, the HG-method samples were the lowest, followed by the YG group, and the DG group had the highest total antioxidant capacity. A correlation analysis revealed a significant relationship between antioxidant capacity and lipids, lipid molecules, nucleosides, nucleotides, and analogs. A metabolomics analysis identified 1937 metabolites from 18 superclasses, with lipids, lipid-like molecules, organic acids and derivatives, organoheterocyclic compounds, and organic oxygen compounds being the predominant metabolites in . Differentially accumulated metabolites (DAMs) in DG samples showed higher levels of lipids and lipid molecules, organic oxygen compounds, organic acids and derivatives, and organoheterocyclic compounds compared to the other drying methods, suggesting DG as the optimal preservation method for . These findings offer insights for selecting appropriate drying methods and maintaining the post-drying quality of .