Thiamine Utilization of Rats Maintained on Diets Containing Dextri-Maltose.

Abstract

Summary

Commercial dextri-maltose contains 0.9 γ thiamine per g by the thiochrome assay. Prophylactic and curative tests with rats have demonstrated that the thiamine present in dextri-maltose-containing diets is utilized by the rat. Rats maintained on rations containing autoclaved yeast showed weight increments in excess of those observed with a diet containing the “heat stable” B factors in crystalline form, although both diets contained 0.5 γ thiamine per g by the thiochrome method. Animals receiving diets containing sucrose and autoclaved yeast, but with thiamine added to the same level (0.5 γ per g) present in dextri-maltose, made essentially the same weight gains in prophylactic tests as did rats fed the ration containing dextri-maltose. However, when the autoclaved yeast was replaced by crystalline vitamins, the animals receiving dextri-maltose grew at a rate in excess of that of rats fed sucrose although the thiamine level of the two diets was the same (0.5 γ per g). The results of these experiments indicate that autoclaved yeast apparently carries factor (s) which augment the effect of small amounts of thiamine in the rat. Thus, the thiochrome method may not measure all thiamine which, according to these bioassays, was available to the rat.