Control of development and valepotriate production by auxins in micropropagated Valeriana glechomifolia

Valeriana glechomifolia is a plant species endemic to southern Brazil that accumulates valepotriates, which are terpene derivatives, in all of its organs. Valepotriates are the presumed sedative generic components of the pharmaceutically used species of Valeriana. The influence of various concentrations of the auxins indole-3-acetic acid, indole-3-butyric acid and -naphthaleneacetic acid on the growth of micropropagated V. glechomifolia was investigated under conditions of transient and continuous exposure. Changes in the development of roots and shoots as well as the production of the valepotriates acevaltrate, valtrate and didrovaltrate (analyzed by high-performance liquid chromatography) were evaluated. The best performance in valepotriate production, growth and survival under ex vitro conditions following plant acclimatization was achieved in the continuous presence of 5.71 M IAA. When cultured in medium containing IAA plants produced stable levels of valepotriates throughout the entire cultivation period.Abbreviations ACE Acevaltrate - IAA Indole-3-acetic acid - IBA Indole-3-butyric acid - DW Dry weight - DID Didrovaltrate - NAA -Naphthaleneacetic acid - PVP Polyvinylpyrrolidone - VAL Valtrate