Analysis of Sesamin, Asarinin, and Sesamolin by HPLC with Photodiode and Fluorescent Detection and by GC/MS: Application to Sesame Oil and Serum Samples

New sensitive and specific analytical methods are needed for the analysis of sesamin, asarinin, and sesamolin in sesame seed oils, sesame dietary supplements, as well as in serum samples from clinical studies involving sesamin, asarinin, and sesamolin. The objective of this study was to develop a high performance liquid chromatographic (HPLC) method with photodiode array and fluorescent detectors and a gas chromatography mass-spectrometry (GC/MS) method for the analysis of sesamin, asarinin (episesamin), and sesamolin in sesame oil and in serum samples. Sesame oil samples were extracted with methanol whereas the serum samples were extracted with ethyl acetate or n-hexane. The individual lignans were analyzed by HPLC using reversed phase C18 columns. Analytical recoveries of sesamin, asarinin, and sesamolin from sesame oil were 92-94 % with two extractions. Recoveries from serum ranged from 87 to 97 %. The limit of quantitation with the fluorometric detector was 0.1 ng compared to 0.1 mu g with the PDA detector. The concentrations of sesamin, asarinin, and sesamolin in Orchids and Sigma sesame oil were 0.4, 0, and 0.15 % and 0.19, 0.09, and 0 %, respectively. The identities of the individual lignans obtained by HPLC were confirmed by GC/MS and the concentrations of sesamin, asarinin, and sesamolin obtained with the fluorometric detector correlated with those obtained by GC/MS (r (2) = 0.94, P < 0.001). The HPLC and GC/MS methods permit simple and efficient procedures for the analysis of sesamin, asarinin, and sesamolin in sesame oil samples as well as in serum samples.