Chemical and Microbiological Differentiation of Enantiomorphs of Galactose and Xylose

An enzyme-P.M.R.-spectroscopic determination of the enantiomers of galactose

The action of D-galactose oxidase on D-galactose in the presence of oxygen afforded meso-galacto-hexodialdose quantitatively, which allowed p.m.r.-spectroscopic determination of the D enantiomer in a DL mixture. In the spectrum of the products obtained from the enzymic treatment of a mixture of D- and L-galactose, the magnitude of the aldehydrol signals derived solely from the oxidised D enantiomer, relative to those of the anomeric signals, provided the fractional content of the D enantiomer. This simple, accurate, and convenient procedure was applied to the hydrolysate of a seaweed galactan, which was also analyzed, for comparative purposes, by the fermentation technique employing D-galactose-adapted Saccharomyces cerevisiae.