Development of a method for the determination of gamma-aminobutyric acid in foodstuffs.

A method for the determination of gamma-aminobutyric acid (GABA) in foodstuffs has been developed by combination of its dinitrophenylation and high-performance liquid chromatography (HPLC) using norleucine as an internal standard. GABA was converted to its stable derivative with 1-fluoro-2,4-dinitrobenzene and the derivative was extracted with ether. After evaporation of the extract, the residue was dissolved in 0.1 M NaOH and the solution was subjected to reversed-phase HPLC with an elution system of a linear gradient of methanol in 10 mM Tris-HCl buffer (pH 6.0) and a detection system monitoring the absorbance of the effluent at 400 nm. The present method was shown to be utilized as a satisfactory method for the determination of gamma-aminobutyric acid in foodstuffs.