Fluorescent Glucoside in the Human Lens

A PROTEIN-FREE extract of the lens of man and other primates contains a fluorescent compound which is absent from the lens of the usual domestic and laboratory animal. This compound, detected on paper chromatograms by its reaction with ninhydrin, was believed to be a peptide1. The protein free extract of the lens of man and certain other primates has been found to contain one or more fluorescent yellow pigments2, and I have now isolated from the human lens the O-β-D-glucoside of L-3-hydroxykynurenine (Fig. 1), which is yellow and highly fluorescent. This glucoside has also been found in the silkworm, Bombyx mori3.