Effect of certain elicitors on production of pyrrolizidine alkaloids in hairy root cultures of Echium rauwolfii

Hairy root cultures of Echium rauwolfii were obtained by infection of sterile apical shoots with Agrobacterium rhizogenes The linear increase in fresh weight was found to be parallel to the alkaloids production. The transformed cultures were exposed to different elicitors, such as methyl jasmonate (MJ), quercetin and salicylic acid in order to increase their productivity. Pyrrolizidine alkaloids were quantitatively determined by HPLC. Estimation of total alkaloids was achieved by peak area calculations MJ at a concentration of 100 mu M induced the accumulation of total alkaloids about 19-fold compared to the untreated control. The flavonoid quercetin (Q) at a concentration of 50 mu M enhanced the pyrrolizidine accumulation approximately 6-fold. The induction effect of both MJ and Q can be suppressed by pre-incubation of hairy root cultures with salicylic acid