Systematic Chemical Profiling and Quality Evaluation Framework for Essential Oil Derived from Epimedium brevicornu Maxim.

In this study, we systematically evaluated how extraction protocol, processing variables, and storage conditions influence the quality of essential oil (EO) isolated from Epimedium brevicornu Maxim. Supercritical fluid extraction (SFE) proved superior to all other methods tested, affording the highest yield and most consistent composition.. Furthermore, this study proposes a comprehensive quality standard for qualified Epimedium EO, covering key parameters such as sensory attributes (appearance, odor), physicochemical properties, main chemical constituents, and hygienic indices. The principal components of the EO were hydrocarbons, alcohols, esters, and ketones, with α-guaiene, sesquiterpenes, patchoulene, and patchouli alcohol (all exceeded 1%) serving as chemotaxonomic markers. Antioxidant profiling revealed that EO prepared by SFE and stored in sealed amber vials at ambient temperature for 50 days (Essential oil-C) retained potent radical scavenging capacity (DPPH IC50 0.05 mg/mL; ABTS IC50 0.0003 mg/mL) and significant reducing power. These results establish a benchmark for the standardization and commercial exploitation of Epimedium EO.