The alleged contamination of carotene by vitamin A

Abstract

that carotene can restore growth in rats receiving diets deficient in vitamin A has now been supported by various workers [Moore, 1929, 1, 2; Collison, Hume, Smedley-MacLean and Smith, 1929; Kawakami and Kimm, 1929]. Negative results, however, were obtained by Duliere, Morton and Drummond [1929, 1, 2], and it was suggested by these workers that pure carotene was inactive, and that samples found to be active must have contained traces of vitamin A as impurity. Recently Hume and Smedley-MacLean [1930] have shown that the real cause of this failure did not lie in the superior purity of the carotene used, but was in all probability traceable to the use of ethyl oleate as a solvent for the test doses. Nevertheless the criticism that even the purest samples of carotene might still contain traces of the familiar vitamin A of cod-liver oil has re- mained incompletely answered.