The sugars of urine

Abstract

THE first paper of this series by West and Peterson [1932] outlines an improved procedure for the determination of fermentable and non-fermentable sugars in urine. Although a number of workers have studied the factors which influence the excretion of these substances, the whole question is in a rather confused and unsatisfactory state. This is largely due to the fact that in much of the older work the methods of analysis were inadequate. This applies especially to the fermentation procedures used, which involved the use of unwashed yeast acting for many hours. Under such conditions it is well recognised that the yeast itself may add an amount of reducing material which may completely offset that removed by the yeast, leading to data which indicate the complete absence of fermentable sugar, or bacterial contamination may cause sugar destruction leading to values for fermentable sugar which are too high. Other sources of error lie in the incomplete removal of non-sugar reducing substances from the urine before analysis and the use of sugar methods incapable of detecting small differences. Benedict and Osterberg [1918] using Hg(NO3)2-NaHCO3 filtrates of urine and the picrate sugar method, studied the effect of diet and starvation upon the excretion of total sugar in the dog. They found this to be highest on a carbohydrate diet, appreciably decreased on a high protein diet and markedly less during starvation. They noted a maximum excretion 4-5 hours, and a minimum excretion about 15 hours, after feeding. They found the output to be independent of urine volume. These workers with Neuwirth [1918] studied both the fermentable and non-fermentable sugars in the urine of two normal men as affected by diet. They found the total excretion to be greater, in general, for a high carbohydrate than for a high protein diet, both fermentable and nonfermentable fractions being increased. Their fermentable values for all experiments on one individual averaged nearly the same as their non-fermentable, something over 500 mg. (calculated as glucose) per 24 hours. The other subject