Metabolic diversity in Coleus forskohlii Briq. of Indian subcontinent.

New economic, easy, specific, accurate, robust, validated high performance thin layer chromatography (HPTLC) and high performance liquid chromatography methods with good range of linearity and sensitivity were developed for quantification of forskolin in ten samples collected from different regions of Indian subcontinent, which showed a large variation among samples (0.074-0.282%, w/w). Metabolic diversity of all the samples using HPTLC fingerprint method showed a total of 16 well separated spots. There is no significant metabolic diversity among the samples collected from different locations of Indian subcontinent, which was obtained from HPTLC fingerprinting. The results of locational variation showed highest content of forskolin in Bengaluru sample by both analytical methods. The validated quantification methods and fingerprint profile together can act as a good authentication tool for coleus as well as for other medicinal plants.