High-Performance Thin-Layer Chromatographic Determination of Three Therapeutic Phenolic Components in Leucas Species

This study was designed to develop a simple, sensitive, selective, and precise high-performance thin-layer chromatography (HPTLC) fingerprint and quantitative estimation method for the analysis of three phenolic compounds from nine Leucas species. The developed HPTLC method was validated according to the International Conference on Harmonization guidelines. The method permits reliable quantification of one important phenolic acid (gallic acid) and two hydroxycinnamic acids (caffeic and ferulic acids) in 50% hydroethanolic extracts on silica gel with toluene—ethyl acetate—formic acid 8:2:1 (v/v) as the mobile phase. The system showed good resolution and separation of caffeic, ferulic, and gallic acids (at RF values 0.48, 0.60, and 0.30, respectively) from the other constituents of the extract. Densitometric scanning was done at 300 nm in absorbance mode. All the results obtained by the developed method were statistically compared for validation parameters, for accuracy and good precision. Caffeic, ferulic, and gallic acids were estimated in all the aforesaid nine Leucas species, but the quantity varied from species to species. Further, these phenolics were reported from the aforesaid Leucas species for the first time, except for Leucas lanata and Leucas urticifolia. However, Leucas biflora, Leucas decemdentata, and Leucas stricta were documented for their chemical constituents for the first time. The proposed HPTLC method can be used for routine quality testing of Leucas species.