Validated HPTLC Method for Dihydrokaempferol-4'-O-glucopyranoside Quantitative Determination in Alcea Species

Dihydrokaempferol-4'-O-glucopyranoside, a flavanonol glucoside, is the major compound in the flower of Alcea rosea L. which possesses significant antioxidant and anticancer activity against HepG-2 cell line and thus can be considered a marker compound for A. rosea L. We attempted to establish a new simple, validated high-performance thin-layer chromatographic (HPTLC) method for the quantitation of dihydrokaempferol-4'-O-glucopyranoside to help in the standardization of the hydroalcoholic extracts of A. rosea L. flowers and to evaluate the best method for its extraction from the plant material. The separation was carried out on an HPTLC aluminum plate pre-coated with silica gel 60F-254, eluted with ethyl acetate-methanol-water-acetic acid (30:5:4:0.15 v/v). Densitometric scanning was performed using a Camag TLC scanner III, at 295 nm. A linear relationship was obtained between the concentrations (0.9-3.6 mg) and peak areas with the correlation coefficient (r) of 0.9971 ± 0.0002. The percentage relative standard deviations of intra-day and inter-day precisions were 0.22-1.45 and 0.49-1.66, respectively. The percentage w/w of dihydrokaempferol-4'-O-glucopyranoside in the flowers of A. rosea L. after maceration and sonication for 15 min was found to be 0.733 g/100 g and 0.928 g/100 g, respectively.