Quantification of bioactive lignans in sesame seeds using HPTLC densitometry: Comparative evaluation by HPLC-PDA

Sesamin and sesamolin constitute the main bioactive secondary metabolites of sesame seeds (Sesamum indicum L., Pedaliaceae). In the present work, a rapid HPTLC-based methodology was developed in compliance with the requirements of the European Pharmacopoeia for the quantification of these two lignans in sesame seeds. A comparative study was simultaneously performed with HPLC-PDA for assessing the sesamin and sesamolin content of diverse samples. Both methods were validated and the results were subsequently subjected to statistical analysis in order to compare their performance as well as to investigate possible correlations. The methods were shown to be adequately correlated in terms of performance, as revealed by Pearson's rank correlation coefficients (>0.99 for sesamin and >0.98 for sesamolin) and Bland-Altman analysis (relative method bias 0.06-0.21, SD of bias 0.05-0.07). HPTLC densitometry could thereby serve as a valid and reliable tool for the rapid determination of the major lignans in sesame seed samples.