26 Thai Pharmaceutical and Health Science Journal, Vol. 2 No. 1, Jan. – Apr. 2007 Original Article Determination of Saponin Glycosides in Bacopa monnieri by Reversed Phase High Performance Liquid Chromatography Watoo Phrompittayarat 1,2 , Sakchai Wittaya-areekul 3 , Kanchalee Jetiyanon 4 , Waraporn Putalun 5 , Hiroyuki Tanaka 6 and Kornkanok Ingkaninan 1,2 * 1 Department of Pharmaceutical Chemistry and Pharmacognosy, Faculty of Pharmaceutical Sciences, Naresuan University, Thailand 2 Cosmetics and Natural Products Research Center, Naresuan University, Thailand 3 Department of Pharmaceutical Technology, Faculty of Pharmaceutical Sciences, Naresuan University, Thailand 4 Department of Agricultural Sciences, Faculty of Agriculture Natural Resources and Development, Naresuan University, Thailand 5 Department of Pharmaceutical Botany and Pharmacognosy, Faculty of Pharmaceutical Sciences, Khon Kaen University, Thailand 6 Department of Medicinal Plant Breeding, Graduate School of Pharmaceutical Sciences, Kyushu University, Japan * Corresponding author: k_ingkaninan@yahoo.com ABSTRACT A reversed phase HPLC system was developed for the quantitative analysis of bioactive saponin glycosides in the medicinal plant, Bacopa monnieri (L.) Wettst (Brahmi). Five dammarane saponin glycosides namely Bacoside A 3 (1), Bacopaside II (2), 3-O-[α-L-arabinofuranosyl(12)-{β-D-glucopyranosyl-(13)}-α-L-arabinopyranosyl] jujubogenin (3), Bacopasaponin C (4) and Bacopaside I (5) were analyzed on a C-18 column. With an isocratic elution of 0.2% phosphoric acid and acetonitrile (65:35 v/v), the separation was obtained in a total run time of 20 min. The method was validated and the applicability of this HPLC method for analyzing saponin glycosides from Brahmi is demonstrated. Key words: Bacopa monnieri, RP HPLC analysis, saponin glycosides Thai Pharm Health Sci J 2007;2(1):26-32 § Introduction Bacopa monnieri (L.) Wettst., commonly known as Brahmi, has been used for a long time in Ayurvedic medicine as nervine tonic for promoting mental health and improving memory 1 . Recently, several studies have been published on the biological effects of this plant, especially for a therapeutic potential in treatment or prevention of neurological diseases and improvement of higher order cognitive processes. 1-5 Triterpenoid saponins, the major components in Brahmi, were reported to be responsible for the cognitive enhancing activity of Brahmi. 1,6 Although several commercial products of Brahmi claimed for memory improvement have been launched in § 12 th year of Srinakharinwirot Journal of Pharmaceutical Sciences the market, only a few reports regarding quality control methods were published. Estimation procedures by using high performance thin layer chromatography (HPTLC) 7 and ultraviolet (UV) detector 8 for the determination of “Bacoside A,” the mixture of active saponins in Brahmi were reported. More precise high performance liquid chromatography (HPLC) methods for quantification of each saponin are available. 9-11 However, in all methods, gradient elution is used and more than 30 min run time is needed. In the present study, we described a simple and accurate isocratic reversed phase (RP) HPLC procedure for a determination of five major saponins in Brahmi. The method was validated and its applicability for quality control purpose was discussed.