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alpha-Tocopheryl quinone is converted into vitamin E in man.

A N Moore·K U Ingold
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Abstract

The conversion of alpha-tocopheryl quinone into alpha-tocopherol in humans has been demonstrated. A male subject was given an oral dose of 400 mg of alpha-3,5-[(C2H3)2]-tocopheryl quinone with an evening meal. Analysis of plasma 15 h later by lipid extraction and subsequent GC-MS single ion monitoring revealed the presence of alpha-[5,7-(C2H3)2]-tocopherol at a concentration of 0.4 microM, representing 0.8% of the total tocopherol in the plasma sample. This experiment clearly demonstrates that orally administered alpha-tocopheryl quinone is converted in a low overall yield to alpha-tocopherol in humans. The conversion to alpha-tocopherol of that portion of the quinone dose which was actually absorbed into the blood stream may, however, have been fairly efficient.

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Administration, OralAgedBiotransformationGas Chromatography-Mass SpectrometryHumansIntestinal AbsorptionMaleVitamin EJournal ArticleResearch Support, Non-U.S. Gov't

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A N Moore, K U Ingold. 1997. alpha-Tocopheryl quinone is converted into vitamin E in man.. https://doi.org/10.1016/s0891-5849(96)00276-6

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