Methyl jasmonate (MJ) enhances the production of a range of secondary metabolites including triterpenoid saponins in a variety of plant species. Here, it enhanced production of bacoside A, a valuable triterpenoid saponin having nootropic therapeutic activity in in vitro shoot cultures of Bacopa monnieri, the only known source of bacoside A. The highest yield was with 50 mu M MJ giving 4.4 mg bacoside A/g dry wt; an 1.8-fold increase (compared to control) after 1 week.