Metabolism of Galactose I. Cutaneous Blood Sugars after Galactose Ingestion by Victor

Our knowledge of the fate of galactose after its oral ingestion has been limited by the analytical methods at our disposal. As a reducing sugar, the galactose could be traced by earlier workers only by methods common to those for glucose. The use of bakers’ yeast enabled these two sugars to be separated. By this means, Blanc0 (l), Corley (Z), and Harding and van Nostrand (3) reduced the number of assumptions used in the interpretation of galactose metabolism. Roe and Schwartzman (4) by using Benedict’s (5) reagent for blood sugar after fermentation have minimized the occurrence of non-sugar reducing substances in the fraction analyzed as galactose. In two papers from this laboratory methods have been developed for the determination of galactose in bloods and urines. Both “galac” yeast (6) and Sacchuromyces marzianus (7) quantitatively remove galactose from Folin-Wu blood filtrates and from urines previously treated with HzS04 and Lloyd’s reagent. The total reducing power of these liquids can be fractionated into (a) fermentable sugars, (b) galactose, and (c) residual reducing substances. It is thus possible to follow the course of galactose in blood and urine after its oral ingestion in man, and to trace its influence, if any, on the other fractions. We have been able to gather further information on its behavior under varying conditions and to clarify many minor points of dispute. Our progress has been helped by our ability to apply this method of sugar fractionation to small amounts of cutaneous blood. All previous work either has been with venous blood, if the separation of fermentable sugar from the remaining reducing substances has