Development and Validation of an HPLC Method for Determination of the Accumulation Patterns of Coumarin and 2-Hydroxycinnamic Acid in Different Parts of <i>Eupatorium Fortunei</i> Turcz. During Growth Stages

To quantify coumarin and 2-hydroxycinnamic acid in Eupatorium fortune Turcz. (EFT), a high-performance liquid chromatography method was developed and rigorously validated. This optimized approach was subsequently applied to analyze the distribution patterns of both compounds across different plant tissues and at various growth stages. The results indicated that the contents of coumarin and 2-hydroxycinnamic acid varied significantly among plant parts and over time. Specifically, the concentrations in leaves substantially exceeded those in stems and roots, establishing the following concentration gradient: leaves > stems > roots. Throughout the growth cycle, the levels of both compounds exhibited two distinct peaks amid a general declining trend. Based on these accumulation dynamics, two harvest periods are recommended within one growth cycle: the optimal harvest time occurs in early May, with a secondary period in early July. Furthermore, the leaves were identified as the most promising medicinal tissue due to their markedly higher bioactive content. These findings offer valuable insights for improving the quality control and agricultural practices related to EFT.