Production of centellosides and phytosterols in cell suspension cultures of Centella asiatica

Centella asiatica is a herbaceous plant used in medicine for its wound-healing and anti-inflammatory properties. Its bioactive compounds are ursane-type triterpene saponins known as centellosides. With the aim of increasing the biotechnological production of these compounds, C. asiatica cell suspensions were established and treated with two concentrations (100 and 200 mu M) of methyl jasmonate (MeJA). The maximum centelloside production was observed in the stationary growth phase, reaching 0.16 mg g(-1) dry weight (DW) at day 25 of the culture in the control and 1.11 mg(-1) g DW at day 15 in the MeJA-elicited cultures. The elicitor did not change the centelloside pattern, with madecassoside being the main compound, followed by asiaticoside. Reverse transcription polymerase chain reaction (RT-PCR) analysis of the beta-amyrin synthase gene (CabAS, the specific oxidosqualene cyclase that leads to centelloside formation) showed higher levels of expression in the elicited cultures than in the control. The maximum content of centellosides was obtained at day 15, with a time lag between gene activation and centelloside biosynthesis. In the cultures elicited with 200 mu M MeJA, the centelloside production did not increase compared to the control. Both elicitor concentrations decreased the content of phytosterols. Thus, MeJa elicitation in this type of culture was dose-dependent and its inducing role was apparent at low concentrations.