Investigations on the preparation and behaviour of vitamin B1 concentrates from yeast

IN a previous publication a method was described for the concentration of vitamin B1 from wheat embryo, which had been attended with a considerable measure of success [Guha and Drummond, 1929]. A semi-crystalline prepara- tion was obtained, of which the pigeon-curative day-dose was found to be of the order of 0 005 mg. It also promoted good growth in young rats, placed on a vitamin Bl-deficient diet, in a daily dose of 0-015 mg. The preparation, however, was obviously inipure, and when subjected to fractionation by gold chloride behaved as if the vitamin had been split into two fractions, as a mixture of the substances obtained from the gold precipitate and filtrate appeared to be more active than either. As, however, a very small amount of material was at our disposal, the number of pigeon and rat tests was very inadequate, and, therefore, our results had to be taken with reserve. Recently, however, Reader [1930] has stated that the experimental "beriberi" condition in rats is a complex syndrome, resulting from a deficiency of two factors, B1 and B4. Furthermore, the crystals obtained by Jansen and Donath [1926] from rice polishings, which were originally claimed to be vitamin B1 hydro- chloride, have also been stated to contain vitamin B4 [Jansen, Kinnersley, Peters and Reader, 1930].