EFFECT OF GLUCOSE ON ASPARTIC-ACID RACEMIZATION

The racemization of aspartic acid in aqueous solution with and without phosphate buffer was found to increase in the presence of d-glucose. This increase in racemization appears to involve the formation of an imine intermediate (Schiff base). Subsequent proton tautomerization leading to the loss of asymmetry during the early stages of melanoidin formation could account for the observed increase in racemization. The racemization reaction did not follow reversible first order kinetics when glucose was added to buffered aspartic acid solution at 80°C; in unbuffered solution reversible first order kinetics were followed up to 624 hr. © 1979.