Yasuko Fukuda

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

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.

Oil and minor components of sesame (Sesamum indicum l.) strains.

Oil and mior components of sesamin and sesamolin were studied in 42 strains ofSesamum indicum L. The oil contents of the seed ranged from 43.4 to 58.8% and varied inversely with the percentage of hull (r=−0.804, significant at the 1% level). The hull percentage was used as a criterion to predict oil content. The percentage of sesamin in the oil ranged from 0.07 to 0.61% and that of sesamolin from 0.02 to 0.48%. There was a significant positive correlation between the oil content of the seed and the sesamin content of the oil (r=0.608, significant at the 1% level); no correlation was found between the oil and sesamolin contents.The average oil content found for the white-seeded strains was 55.0% and for the black-seeded strains 47.8%, the difference of 7.2% being significant at the 1% level. The white- and black-seed strains also differed significantly in sesamin content, but not in sesamolin content.

Marked Antioxidative Activity of Seed Oils Developed by Roasting of Oil Seeds Part I. Synergistic Action of the Antioxidative Components in Roasted Sesame Seed Oil.

1) 焙煎ゴマ油の濃褐色成分はアンバーライトXAD-7に吸着し,グリセリドを主成分とする非極性の区分と分離することができた.2) 濃褐色成分をさらにシリカゲルカラムクロマトグラフィーにより分画した.酢酸エチル,メタノール溶出区分は褐色,濃褐色を呈し,抗酸化性を示したが,これらの区分にはセサモールやトコフェロールはほとんど検出されなかったので,未知の抗酸化成分の存在が示唆された.3) 焙煎ゴマ油中の抗酸化物質であるセサモール,トコフェロール,弱い抗酸化性を示したセサミン,2)で分画した酢酸エチルおよびメタノール区分の抗酸化性および相乗作用について重量法で調べた.その結果,酢酸エチルおよびメタノール区分そのものの抗酸化性はそれほど高くなく,また,焙煎ゴマ油に含まれるどの抗酸化物質も単独ではゴマ油の高い抗酸化性には及ぼなかった.4) 焙煎ゴマ油中の4種の抗酸化成分(セサモール,トコフェロール,セサミン,メタノール溶出区分)をこの油中の含量に相当する量でリノール酸に添加して,相乗作用を検討した.2種ずつを組み合わせるとセサミン+メタノール溶出区分の組み合わせを除いて活性が高まり,特にトコフェロールとの組み合わせで著しく活性が高まった.3種,4種の混合でさらに高い活性が得られ,特に,4種の混合が最も高い抗酸化性を示した.