HPTLC fingerprinting and quantification of lignans as markers in sesame oil and its polyherbal formulations

Sesamum (Sesamum indicum) seed and its oil have been in use in Indian traditional medicine, 'Ayurveda' since antiquity. However, there has been no attempt to standardize the polyherbal formulations containing sesamum oil as the main ingredient in terms of its active principle or marker compound. Biologically active lignans in sesamum oil are identified as the marker compound for the oil and its formulations. In this report, a simple, rapid and sensitive HPTLC method is described for the first time to identify and quantify sesamin and sesamolin, the major lignans of the sesamum oil and the method was applied to polyherbal formulations containing the oil for their quantitative estimation. The method was validated in terms of its calibration curve, limits of detection and quantification, precision, accuracy and robustness following standard protocols. The method thus developed was applied to sesamum oil and its commercial herbal formulations to quantify sesamin and sesamolin. The method for fingerprints of the formulations in the form of densitogram following charring of the chromatographic plate was also developed that could be useful for marker-based quality assurance of the polyherbal products containing sesamum oil.