Stability studies of crude plant material of Bacopa monnieri and quantitative determination of bacopaside I and bacoside A by HPLC.

摘要

Introduction - Bacopa 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. Objective - Quantification of bacopaside I and bacoside A in crude plant material of BM stored under the stability study conditions by HPLC. Methodology - Crude BM samples were stored at long-term (LS; 30 degrees C and 65% RH), accelerated (AS; 40 degrees C and 75% RH) and real-time (RT) study conditions. HPLC of BM extracts was carried out using a LiChroCART PurospherReg. STAR RP-18 endcapped column along with a guard column, Purospher STAR RP 18e 4.0 4.0 mm 5 micro m 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. Results - The 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. Conclusion - The 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.