School of Bioscience and Biotechnology, Tokyo University of Technology.
Graduated School of Agricultural Science, Tohoku University.
J Oleo Sci. 2021 Apr 2;70(4):503-507. doi: 10.5650/jos.ess20277. Epub 2021 Mar 10.
In this study, we investigated the compositions of vitamin E tocochromanol [tocopherol (Toc) and tocotrienol (T3)] in crude and refined rice bran oil (RBO) produced in Japan and other countries, including Brazil, Thailand, and Vietnam, based on high-performance liquid chromatography analysis. All RBO analyzed contained α-, β- and γ-Toc and α-, γ- and δ-T3. Japanese crude RBO, although not refined RBO, also contained β-T3. Furthermore, total Toc contents in both Japanese crude and refined oils were found to be higher than those in the crude and refined RBO from other countries. Total T3 contents in Japanese crude RBO were similar to those in the crude RBO from Brazil and Vietnam. The α-Toc and α-T3 contents in Japanese crude and refined RBO were considerably higher than those in the crude and refined RBO produced in other countries, whereas in contrast, γ-Toc and γ-T3 contents in Japanese crude and refined RBO were lower. Consequently, the ratios of total α-Toc and α-T3 contents to total γ-Toc and γ-T3 contents in Japanese crude and refined RBO (1.75 and 1.91, respectively) were notably higher than those in the crude and refined RBO produced in other countries. Similarly, the ratios of total Toc to total T3 in Japanese crude and refined RBO were higher than those in the crude and refined RBO produced in other countries. These results accordingly indicate that the ratio of total α-Toc and α-T3 contents to γ-Toc and γ-T3 contents could be used as an effective index to discriminate between the RBO produced in Japan and that produced in other countries.
在这项研究中，我们使用高效液相色谱分析法，调查了日本及其他国家（巴西、泰国和越南）生产的糙米油（RBO）中的维生素 E 生育三烯酚[生育酚（Toc）和生育三烯醇（T3）]组成。所有分析的 RBO 均含有 α-、β-和 γ-Toc 以及 α-、γ-和 δ-T3。日本粗制 RBO 虽然未经精制，但也含有 β-T3。此外，日本粗制和精制油中的总Toc 含量均高于其他国家的粗制和精制 RBO。日本粗制 RBO 中的总 T3 含量与巴西和越南的粗制 RBO 相似。日本粗制和精制 RBO 中的 α-Toc 和 α-T3 含量明显高于其他国家的粗制和精制 RBO，而相反，α-Toc 和 α-T3 含量则低于日本粗制和精制 RBO。因此，日本粗制和精制 RBO 中的总 α-Toc 和 α-T3 含量与总 γ-Toc 和 γ-T3 含量的比值（分别为 1.75 和 1.91）明显高于其他国家的粗制和精制 RBO。同样，日本粗制和精制 RBO 中的总Toc 与总 T3 的比值高于其他国家的粗制和精制 RBO。这些结果表明，总 α-Toc 和 α-T3 含量与 γ-Toc 和 γ-T3 含量的比值可以作为区分日本和其他国家生产的 RBO 的有效指标。
