High-performance thin-layer chromatography (HPTLC) method development and validation for the quantification of catechin in the hydroalcoholic extract of Parkia roxburghii seed

Parkia roxburghii pod is a very popular food in North East India, known as Yongchak. Traditionally, it is used for the treatment of blood pressure, piles, diabetes, dysentery and urinary tract infections. The seeds contain many phytochemicals like flavonoids, alkaloids, saponins, terpenoids and tannins which are responsible for their medicinal properties. High-performance thin-layer chromatography (HPTLC) plays a major role in the quality control of plant extracts/formulations. This study aims to develop and validate a HPTLC method for the quantification of catechin from hydroalcoholic extract (70:30) of P. roxburghii seeds. The separation was executed using the solvent system of ethyl acetate‒acetic acid‒formic acid‒water (10:1:0.75:1, V/V) on a 10 × 10 cm TLC aluminium plate pre-coated with silica gel 60F254. HPTLC fingerprinting and quantification were performed by densitometric scanning at a speed of 100 mm/s, 6 × 0.45 nm micro-slit dimension and optimized at 302 nm in absorbance mode. The method was validated using the International Council for Harmonisation guidelines in terms of accuracy and precision in which the sample drug provided a compact peak at RF 0.61 equivalent to catechin as a standard marker. The quantification and detection limits were 37.23 and 12.32 ng/band, respectively. The quantity of catechin in the hydroalcoholic extract of P. roxburghii seeds was found to be 2.24% w/w. This validated HPTLC method can be used for the standardization and quantitative analysis of catechin in P. roxburghii seed extracts/formulations, being helpful in the quality control.