Phytochemical investigation of bioactive Emodin and quercetin in Cassia fistula and Cassia tora plant parts by HPTLC

In the present study, HPTLC method was developed and validated for the determination of a Emodin (anthraquinone) and Quercetine (flavonoid) in Cassia fistula and Cassia tora (family: Cesalpineceae) flower and stem extract. Appropriate mobile phases were found as n-hexane: ethyl acetate (7:3V/V) for Emodin (Compound 1) and toluene: ethyl acetate: formic acid (2.5:2:0.3V/V) for Quercetine (Compound 2). The densitometric determination was carried out for both compounds. These plates were scanned at 437nm & 254 nm absorbance / reflection mode respectively as Compound 1 & 2. Validation parameters such as linearity range, limit of detection and limit of quantification, regression analysis, sensitivity etc. Regression analysis shows the calibration data is in the range of 0.5 to3 μg for Compound 1, with correlation coefficient (r2) value 0.977 whereas 2 to10 μg for Compound 2 with correlation coefficient (r2) value0.991.The equation indicates that a unit increase in the concentration of Compound 1& 2 results in an increase in the detector response. Low magnitude of residual values indicates a good agreement between observed and calculated values. The accuracy of the proposed method is determined by performing replicate analysis, which indicates high accuracy as actual amount obtained close to theoretical amount. The robustness of proposed HPTLC method was checked with chamber saturation, as it has a pronounced influence on saturation profile.