Ames S R
J Nutr. 1979 Dec;109(12):2198-204. doi: 10.1093/jn/109.12.2198.
The bipotencies of several forms of vitamin E were determined by the rat fetal-resorption bioassay. RRR-alpha-tocopheryl acetate compared with 2-ambo-alpha-tocopheryl acetate had a mean relative potency (RP) of 1.66, significantly higher than the currently accepted value of 1.36. RRR-alpha-tocopheryl hydrogen succinate compared with 2-ambo-alpha-tocopheryl acetate had a mean RP of 1.125, significantly lower than the currently accepted value of 1.21. RRR-alpha-tocopherol compared with 2-ambo-alpha-tocopherol had a mean RP of 1.31, not significantly different from the currently accepted value of 1.36. Some preparations of all-rac-alpha-tocopheryl acetate compared with 2-ambo-alpha-tocopheryl acetate had a mean RP of 0.81, and compared with RRR-alpha-tocopheryl acetate had a mean RP of 0.52. Both RP values are significantly lower than the currently accepted values of 1.00 and 0.725 (the reciprocal of 1.36) respectively. Similar biological activities were obtained for oily and dry preparations of the same forms of alpha-tocopheryl acetate. A basic assumption of stoichiometric equivalence for the acetate and hydrogen succinate of RRR-alpha-tocopherol, inherent in the currently accepted values, was shown to be incorrect. The results show that the unit/weight relationships for the various forms of vitamin E currently assigned by the National Formulary have not been validated using a bioassay based on biological function.
通过大鼠胎儿吸收生物测定法测定了几种形式维生素E的双效性。与2-消旋-α-生育酚醋酸酯相比，RRR-α-生育酚醋酸酯的平均相对效价（RP）为1.66，显著高于目前公认的1.36的值。与2-消旋-α-生育酚醋酸酯相比，RRR-α-生育酚氢琥珀酸酯的平均RP为1.125，显著低于目前公认的1.21的值。与2-消旋-α-生育酚相比，RRR-α-生育酚的平均RP为1.31，与目前公认的1.36的值无显著差异。所有消旋-α-生育酚醋酸酯的一些制剂与2-消旋-α-生育酚醋酸酯相比，平均RP为0.81，与RRR-α-生育酚醋酸酯相比，平均RP为0.52。这两个RP值分别显著低于目前公认的1.00和0.725（1.36的倒数）的值。相同形式的α-生育酚醋酸酯的油性和干燥制剂获得了相似的生物活性。目前公认值中固有的RRR-α-生育酚醋酸酯和氢琥珀酸酯化学计量当量的基本假设被证明是不正确的。结果表明，美国国家处方集目前指定的各种形式维生素E的单位/重量关系尚未通过基于生物学功能的生物测定法进行验证。
