The Isolation and Identification of O-Xylosyl-serine and S-Methylcysteine Sulfoxide from Human Urine*

Abstract

Two unknown ninhydrin-reacting substances have been isolated from normal human urine and identified as O-xylosyl-serine and S-methylcysteine sulfoxide, respectively. The average yields of O-xylosyl-serine and S-methylcysteine sulfoxide from 100 1 of urine were approximately 100 mg and 150 mg, respectively. O-xylosyl-serine was confirmed to be a glycoside in which L-serine is linked to xylose through its hydroxyl group, and was suggested to have [beta]-configuration.