Effects of salicylic acid elicitor on the production of tropane alkaloids (atropine and scopolamine) in hairy roots and in vitro roots cultures of Hyoscyamus niger L.

Tropane alkaloids such as atropine and scopolamine have wide application in the treatment of diseases such as asthma and antispasmodic due to anticholinergic agents. In the present study, the effects of salicylic acid (SA) on the production of two alkaloids, atropine and scopolamine ,were studied in hairy root and in vitro grown root cultures of Hyoscyamus niger L. The roots were cultured in liquid B5 medium containing different concentrations of SA (0, 0. 1, 1, 2 and 4 mM) in various exposure times (24, 96 and 168 hours). Eventually, root growth index, and atropine and scopolamine content were assayed after 30 days. In in vitro grown roots, treatment with 1mM SA resulted in the highest production of atropine after 168 hours, while the highest amount of scopolamine (649.53 µg/g D. W) was obtained in 2mM SA (after 96 hours), showing more than 13-fold increase compared to the control. In hairy root cultures, the most significant contents of atropine were observed in the medium containing 2mM SA after 96 h. Moreover, the highest content of scopolamine was achieved in medium treated with 0.1 mM SA after 96 hours. In general, atropine content in hairy roots was considerably higher than that of in vitro grown roots. In contrast, scopolamine content in in vitro grown roots was significantly more than that of hairy roots. Moreover, the rate of root growth declined as a result of increasing of elicitor concentration in the medium.