Activation of Ergosterol at –180°C

Abstract

WITH reference to the letter in NATURE of Mar. 24, p. 452, from Dr. Bills and Mr. Brickwedde, on the activation of cholesterol at liquid oxygen temperature, we may mention that we are now studying the production of vitamin D from ergosterol by ultra-violet radiation at various temperatures, and have obtained intensely active products at – 180° C. from weak alcoholic solutions immersed in liquid oxygen, as well as at higher temperatures up to + 78° C. Details will be published shortly. Our results therefore are similar to those of Bills and Brickwedde, and are made with the pure provitamin instead of with cholesterol.