ABSTRACTIntroductionBacopa monnieri (BM) contains several dammarane‐type triterpenoid saponins including bacopaside I and bacoside A. These bioactive compounds may be used as chemical markers for the quality control of different BM products used for promoting mental health and intellect.ObjectiveQuantification of bacopaside I and bacoside A in crude plant material of BM stored under the stability study conditions by HPLC.MethodologyCrude BM samples were stored at long‐term (LS; 30°C and 65% RH), accelerated (AS; 40°C and 75% RH) and real‐time (RT) study conditions. HPLC of BM extracts was carried out using a LiChroCART Purospher® STAR RP‐18 endcapped column along with a guard column, Purospher STAR RP 18e 4.0 4.0 mm 5 µm using a gradient of acetonitrile (A) and water containing 0.05% (v/v) orthophosphoric acid (B) at a flow rate 1.5 mL/min with UV detection at 205 nm.ResultsThe linear range of bacopaside I and bacoside A was 0.2 to 1 mg/mL. With the help of a regression equation the coefficient of determination (r2) values for bacopaside I and bacoside A were found to be > 0.999 and > 0.994 respectively. Relative standard deviation (RSD) values were < 4.0 for all the concentrations injected (n = 3). The HPLC study indicated that BM samples kept under LS condition are rich in saponin contents as compared with the samples stored under AS and RT study conditions.ConclusionThe study indicated that BM plant material should be used fresh to obtain maximum concentration of active saponins or it should be stored under LS conditions up to 3 months. Copyright © 2012 John Wiley & Sons, Ltd.