Seasonality of Coumarin Composition and Antioxidant Activities in Daphne jejudoensis

Daphne jejudoensis, an endemic plant found in Gotjawal area in Jeju Island, was reported as a new species in 2013 due to its distinct characteristics and distribution, which differentiate it from its related species, D. kiusiana. This study focuses on the comparative phytochemical analysis and antioxidant activities of D. jejudoensis leaves based on the collection period in order to identify the optimal harvest time. Daphnin and daphnetin were identified as the major components with the highest content observed in samples collected during spring, and the highest antioxidant activities were recorded during the same time period. This study represents the first investigation into the quantitative analysis of daphnin and daphnetin in the leaves of D. jejudoensis based on the collection period.