Quantitative Analysis of Bacoside A from Bacopa monnieri, Collected from Different Geographic Regions of India, by High-Performance Thin-Layer Chromatography-Densitometry

Context: Bacoside A, a triterpenoid saponin, is a major constituent isolated from Bacopa monnieri (L.) Wettst. (Scrophulariaceae), used as a memory enhancer. Bacoside A and B are active ingredients in Bacopa herb and have antioxidant and hepatoprotective activities. Objective: A new rapid, simple, and economical high-performance thin-layer chromatographic (HPTLC) method was developed and validated for densitometric quantitative analysis of bacoside A in powdered leaves from different geographical regions of India. Materials and methods: An amount of 10 mg mL(-1) methanol extract of powdered leaves from different geographic regions was used for sample application on precoated silica gel 60 F-254 aluminum sheets. Standard bacoside A (1 mg mL(-1)) was used for calibration curve. HPTLC separation was performed on percolated silica gel aluminum plate 60 F-254 (20 cm x 10 cm with 0.2 mm thickness) as a stationary phase using ethyl acetate-methanol-water (4:1:1) as the mobile phase. Quantification was achieved by densitometric analysis at 598 nm over the concentration range of 500-4000 ng band(-1). Result: Compact and well-resolved bands for bacoside A from powdered leaves of different geographic regions were found at retardation factor (R-F) 0.53 +/- 0.02. The linear regression analysis data for calibration curve showed good linear relationship with regression coefficient r(2) = 0.9996 and r(2) = 0.99810 with respect to peak area and peak height. The method was validated for precision, recovery, and robustness as per the International Conference on Harmonization (ICH) guidelines. Variation in quantitative analysis of bacoside A in powdered leaves sample from different geographic regions was found by HPTLC method. Discussion and conclusion: The highest and lowest content of bacoside A in powdered leaves sample from Jammu and Kerala regions, respectively. The variety of B. monnieri in Jammu is superior to other regions of India. The proposed developed HPTLC method can be applied for the quantitative determination of bacoside A in powdered leaves of plant and its formulation.