Development and validation of a high-performance thin-layer chromatography method for the simultaneous estimation of four cardioprotective triterpenoids in Terminalia arjuna W. & A. bark and a fermented polyherbal biomedicine

Terminalia arjuna W. & A. bark is used as a cardioprotective herb in various traditional preparations. It consists of the oleanane class of triterpenoids as cardioprotective principles. In this study, we have developed and validated a simultaneous estimation method for four isolated triterpenoids and determined their biotransformation in a fermented formulation, Arjunadyarishta. A robust high-performance thin-layer chromatography (HPTLC) method was developed for the separation of arjunic acid, arjungenin, arjunetin and arjunglucoside-I. The mobile phase was optimized as ethyl acetate–toluene–tetrahydrofuran–acetic acid (10:5:4:1, V/V ) over pre-coated HPTLC silica gel 60 F 254 plates. The HPTLC plate was developed to a distance of 70 mm at 23 ± 4 °C in a chamber previously saturated for 20 min. The method was validated for linearity, accuracy, precision, robustness, limit of detection, limit of quantification and specificity. The correlation coefficients 0.998 to 0.999 of the compounds with average recoveries of 96.25% to 102.6 were found satisfactory. The developed method can be used successfully for the quality control and quality assurance of T. arjuna formulations, where the stem bark is used. Arjunic acid content was found to be higher in the raw herb whereas arjungenin content was higher in the fermented formulation. Graphical abstract