Abstract
In this study, we have developed a validated high-performance thin-layer chromatography (HPTLC) method for the concurrent estimation of the biomarkers beta-amyrin and beta-sitosterol in dichloromethane and ethanol extracts of the aerial parts of Tinospora cordifolia (TCDC and TCET) and Calotropis gigantia (CGDC and CGET). Chromatographic estimations were carried out on HPTLC (glass-backed silica gel 60 F-254) plates with solvents hexane and ethyl acetate in the ratio of 7.5:2.5, v/v (as the mobile phase). Post development, the plate was derivatized with p-anisaldehyde reagent to furnish compact spots of beta-amyrin and beta-sito-sterol and scanned at lambda(max) = 530 nm. Well-resolved, compact as well as intense peaks of beta-sitosterol (R-F = 0.26 +/- 0.001) and beta-amyrin (R-F = 0.39 +/- 0.001) were found. The linear regression equation and the correlation coefficient square (r(2)) for beta-amyrin (Y = 6.118x + 460.76 and 0.9959) and beta-sitosterol (Y = 7.109x + 1069.1 and 0.9967) in the concentration range of 100-1400 ng spot(-1) indicated good linear relationship. The low values of the percent relative standard deviation (% RSD) for intra-day and inter-day precisions for beta-amyrin (1.003-1.148 and 0.993-1.105) and beta-sitosterol (0.578-0.969 and 0.513-0.813) suggested that the method is precise. The % recovery and % RSD values were found to be 98.42-99.29% and 1.103-2.103, respectively, for beta-amyrin and 98.33-99.39% and 1.375-2.346, respectively, for beta-sitosterol, which confirms the good accuracy of the proposed method. The quantity of beta-amyrin in TCDC, CGDC, TCET, and CGET was found to be 70.14, 10.76, 4.85, and 0.87 mu g mg(-1), respectively, of the dried weight of the extracts, while the beta-sitosterol content was found to be 19.4, 18.5, 1.18, and 0.27 mu g mg(-1), respectively. The highest quantity of beta-amyrin and beta-sitosterol in the dichloromethane fractions of T. cordifolia and C. gigantia validated the wide range of their proved activities including antioxidant, anticancer, and hepatoprotective features. The above developed method can be further employed in the analysis of these markers in marketed preparations.