Centelloside production in Centella asiatica cell suspension cultures elicited with methyl jasmonate

Centella asiatica is a herbaceous plant used in medicine for its wound-healing and anti-inflammatory properties [1]. Its bioactive compounds are ursane-type triterpene saponins known as centellosides. With the aim of biotechnologically increasing the production of these compounds, C. asiatica cell suspensions were established and treated with two concentrations of methyl jasmonate (100µM and 200µM), an elicitor that induces the biosynthesis of many secondary metabolites [2]. The cell suspensions were established from 20g friable calli cultured on a shaking 200ml MS medium [3]. The maximum centelloside production was observed in the stationary growth phase, reaching 160µg/gPS in the control and 1.110µg/gPS in the methyl jasmonate-elicited cultures. The effect of the elicitor was greatest during the first 4 days of treatment and it did not change the centelloside pattern, madecassoside being the main compound, followed by asiaticoside. RT-PCR analysis of the beta -amyrin synthase gene (the specific oxidosqualene cyclase that leads to centelloside formation) showed higher levels of expression in the elicited cultures than in the control, peaking at 20h. The maximum content of centellosides was obtained at day 15 of culture, showing a time lag between the gene activation and centelloside biosynthesis. In the 200µM methyl jasmonate-elicted cultures the expression level of the gene remained much lower than in the 100µM-elicited cultures and the centelloside production did not increase compared to the control. Thus, methyl jasmonate elicitation in this type of culture was dosis-dependent and its inducing role was apparent at low concentrations. Acknowledgements: This work was partially supported by grants from Spanish Ministerio de Ciencia e Innovación (BIO2008–01210) and the Generalitat de Catalunya (2009SGR1217) References: 1. Skopinska-Rózewska et al. (2002) Central-Europ J Immunol. 27: 142. 2. Gundlach et al. (1992) Proc Nat Acad Sci USA 89: 2389. 3. Murashige and Skoog (1962) Physiol Plant. 15: 473.