Contribution of lignan analogues to antioxidative activity of refined unroasted sesame seed oil

Abstract A lignan compound, P3, having strong antioxidative activity was found to be formed in high concentration during the industrial bleaching process of unroasted sesame seed oil. P3 (named sesaminol) was identical to a minor constituent previously isolated from acetone extract of sesame seed. It was shown that sesamolin in unprocessed sesame oil is the source of seaseminol, and the formation of seasaminol was confirmed by the model experiment with corn oil to which sesamolin had been added. Sesaminol was not so greatly removed by the deodorization process that follows bleaching as was sesamol, and it was shown to be at a concentration of ca. 100 mg/100g in commercial refined unroasted seed oil. The antioxidative activity of sesaminol was foughly equal to those of sesamol and γ‐tocopherol by the thiocyanate method. Therefore, it seems that the antionxidative activity of refined unroasted seed oil is mainly attributed to sesaminol.