Mass production of Eleutherococcus koreanum plantlets via somatic embryogenesis from root cultures and accumulation of eleutherosides in regenerants

Eleutherococcus koreanum (E. koreanum) is an endangered medicinal plant, which has been used for the treatments of rheumatism, diabetes and hepatitis. An in vitro methodology has been developed for mass propagation of E. koreanum by using adventitious root explants in liquid cultures. Among the various strengths of Murashige and Skoog media sucrose and growth regulators tested, 1/3 strength hormone-free medium supplemented with 60 g l−1 sucrose was found suitable for embryo induction and development from the root segments. Embryos which were developed on the root segments were able to mature and germinate in the same 1/3 MS hormone-free medium. Bioreactor cultures were established for large-scale cultivation of plantlets. Adventitious roots, embryos and plantlets could be simultaneously harvested after 12 weeks cultivation of adventitious roots in 1/3 strength MS medium supplemented with 60 g l−1 sucrose. HPLC analysis revealed that biomass harvested (somatic embryos, plantlets and adventitious roots) contained eleutheroside B and E in considerable amount, and this could be used for the extraction of these phytochemicals. The present system for plantlet production from root explants would provide an efficient means to produce both plantlets and phytochemicals from E. koreanum.