Establishment of adventitious root co-culture of Ginseng and Echinacea for the production of secondary metabolites

We have successfully established the co-culture of ginseng (Panax ginseng C.A. Meyer) and echinacea [Echiancea purpurea (L.) Moench.] adventitious roots for the production secondary metabolites. Adventitious roots of ginseng and echinacea were cultured in different proportions (5 g L⁻¹; 4:1, 3:2 and 2:1 ginseng and echinacea, respectively) in 5-L capacity airlift bioreactors containing 4 L Murashige and Skoog medium supplemented with 25 μM indole-3-butyric acid and 50 g sucrose L⁻¹ and maintained at 25°C in the dark for 40 days. Results showed the negative effect of echinacea adventitious roots on the growth of ginseng roots, however, by limiting the inoculum density of echinacea, it was possible to establish the co-cultures. To enhance the accumulation of secondary metabolites, co-cultures were treated with 200 μM methyl jasmonate after 30 days of culture initiation. Methyl jasmonate elicitation promoted the accumulation of ginsenosides in the co-cultures. It was possible to produce ginsenosides and caffeic acid derivatives in higher amounts by establishing co-cultures with higher inoculum proportion of ginseng to echinacea (4:1 and 3:2) followed by elicitation treatment. This work demonstrates the effectiveness of interspecies adventitious root co-cultures for the production of plant secondary metabolites.