Optimization of chiisanoside and chiisanogenin isolation from Eleutherococcus sessiliflorus (Rupr. & Maxim.) leaves for industrial application: A pilot study

Chiisanoside and chiisanogenin, which have been reported to have various bioactivities, were the most representative components of the leaves of Eleutherococcus sessiliflorus. The purpose of this study was to establish an optimal harvest period to increase bioactive chemical components and to utilize them as industrial crop materials under the quality control process of E. sessiliflorus. The extraction conditions of leaves were optimized to maximize the main two components using response surface methodology with a Box-Behnken design. The chemical structures of compounds 1–18 isolated from leaves under optimal extraction conditions were identified via NMR and HRMS. Using the chemical profile of leaves by the established UPLC-QTOF-MS and PDA methods, the yields of chiisanoside and chiisanogenin were inversely proportional, and the optimal harvest time from April to September was determined as July for those two components. This study could be used to develop high-quality products, including functional medicinal crops and health supplements, using E. sessiliflorus leaves.