Enhancement strategies of bioactive compound production in adventitious root cultures of Eleutherococcus koreanum Nakai subjected to methyl jasmonate and salicylic acid elicitation through airlift bioreactors

To establish an attractive method for the annual production of valuable Eleutherococcus koreanum-based bioactive compounds, the adventitious roots in airlift bioreactors were subjected to methyl jasmonate (MJ) and salicylic acid (SA) treatment for 1 week before harvest as a chemical elicitor to enhance the productivity of bioactive compounds. After 6 weeks of culture, the addition of 50 µmol MJ was found to be the optimal concentration and elicitor type for biomass and bioactive compound production in the roots, as evidenced by the highest biomass and total production of five target bioactive compounds (i.e., eleutherosides B and E, chlorogenic acid, and total phenolics and flavonoids) without causing any physiological disorders. The total production of the target bioactive compounds at 50 µmol MJ (303.93 mg L−1) was 37.77 % higher than that for the control treatment, and the addition of high concentrations of MJ and SA increased 2,2-diphenyl-1-picrylhydrazyl activity and hydrogen peroxide content in the roots. In addition, the adventitious roots subjected to 50 µmol MJ for 1 week had a competitive edge for commercial use, as evidenced by the high total production of the five target bioactive compounds (per 1 L of medium) when compared to the 3-year field-grown plants.