Use of electrodialysis to separate and concentrate γ-amino butyric acid

Microbial or enzymatic conversion of L-glutamic acid (Glu) is used to produce γ-aminobutyric acid (GABA). GABA recovery from several model solutions was demonstrated with two desalting electrodialysis units, equipped with commercial membrane cartridges for cation recovery. The effect of pH in 50 g/L of GABA model solution on GABA recovery was investigated using the first unit; the GABA recovery rate was approximately 85% at pH 3. The influence of initial GABA concentrations on the process performance was investigated using the second unit; the GABA recovery rate, Glu exclusion rate, current efficiency, and energy consumption were 82–89%, 91–94%, 81–85%, and 0.197–0.204 kWh/kg, when using 80 and 150 g/L of GABA model solutions containing 20 g/L Glu.