Oxidation of βCarotene : Formation of Vitamin A Acid

Abstract

ALTHOUGH Moore¹ had demonstrated that β-carotene was transformed into vitamin A in the animal body, the actual process of this transformation has not as yet been fully understood. There are two views: one postulating oxidation of β-carotene at the central double bond, with the formation of, at first, two molecules of retinene^2,3 (vitamin A aldehyde), which are immediately reduced to give two molecules of vitamin A alcohol; the other claiming that if an excentric bond be attacked it would give only one molecule of vitamin A, resulting from the further degradation of the larger fragment. Moore⁴ has given an outline of the evidence for and against these views.