Determination of glyoxalase activity.

Dakin and Dudley (1) and Keuberg (2) discovered the enzyme glyoxalase in 1913, and showed that it could convert methylglyoxal to lactic acid. The usual assay for this enzyme is a manomctric procedure (3). In 1928 Ariyama (4) described a method for the calorimetric determination of glyoxals involving the ability of these compounds to reduce Benedict’s uric acid reagent (5) in an alkaline medium. Under his optimal conditions, Ariyama measured between 580 and 870 y of glyoxal. By halving the volumes of the reagents he could detect as little as 607 of glyoxal. A modification of Ariyama’s procedure, to be described herein, enables one to measure as little as 2 y of methylglyoxal and also permits the determination of glyoxalase activity of tissues by examining the disappearance of methylglyoxal.