Enzyme Inhibition of the Advanced-Stage of the Maillard Reaction

Abstract

We extracted α-ketoaldehyde dehydrogenase (α-KAD) from rabbit's liver (New Zealand White, body weight 3kg). The α-KAD reacted with methylglyoxal as a substrate in the presence of coenzyme NAD with a Km value of 0.24 mM. Preincubation of glycated bovine serum albumin as a substrate with NAD and α-KAD at 0°C or 30°C for 2 hours caused significantly smaller increases in fluorescence intensity after subsequent incubation for 7 days at 37°C, compared with samples preincubated without α-KAD at 37°C. Preincubation of glycated bovine serum albumin for 2 hours with α-KAD and NAD at 30°C caused the smallest increase in fluorescence intensity after 7 days of subsequent incubation.
These findings suggest that α-KAD may inhibit the formation of the advanced Maillard products.