Effect of salicylic acid on eleutheroside accumulation in the adventitious root culture of Eleutherococcus koreanum

Eleutherococcus koreanum is a useful medicinal plant that has been used to alleviate many ailments including diabetes, hypertension and neuralgia. This plant has known to contain various beneficial compounds including eleutherosides (B, E, and E₁), coumarins, and polyacetylenes. This study was carried out to investigate the dose-dependent effect of salicylic acid (SaA) on both the adventitious root growth and the accumulation of various eleutherosides in the bioreactor culture of Eleutherococcus koreanum. The highest biomass production (3.5g DW/L) was observed in the absence of SaA. Although the root growth was significantly decreased by increasing the SaA concentration, SaA stimulated the production of both eleutheroside B and E. The highest level of eleutheroside B (14.2µg/g DW) and E (141.8µg/g DW) were obtained at 120 and 80µM of SaA. Total eleutheroside was increased up to 374.7µg per liter when SaA was not applied. In addition, when the adventitious roots were cultured with 80µM of SaA, eleutheroside B was decreased by increasing the SaA concentration. The highest levels of eleutheroside E and E₁ were observed at the 9th day, respectively.