Spectroscopic studies of brunescent cataractous lenses

The absorption spectra of brunescent cataractous lenses and their homogenates were analyzed under various conditions by using a double wavelength spectrophotometer. The absorption spectra of the samples were in good agreement with those of synthetic xanthommatin derived from 3-hydroxykynurenine. The results provided evidence that brown pigment in the brunescent cataractous lenses is mainly composed of xanthommatin.