γ-Aminobutyric acid (GABA)

a natural non-protein amino acid

plays an irreplaceable role in regulating the life activities of organisms. Nowadays

the separation and purification of food-grade GABA from fermentation broth is still a great challenge. This research utilized monosodium glutamate as a substrate for the production of high-purity GABA

via

an integrated process incorporating fermentation

purification

and crystallization. Firstly

147 g·L

-1

GABA with a yield of 99.8% was achieved through fed-batch fermentation by

Lactobacillus brevis

CE701. Secondly

three integrated purification methods by ethanol precipitation were compared

and crude GABA with a purity of 89.85% was obtained by the optimized method. Thirdly

GABA crystals with a purity of 98.69% and a yield of 60% were further obtained through a designed crystallization process. Furthermore

the GABA industrial production process model was established by Superproper Designer V10 software

and material balance and economic analysis were carried out. Ethanol used in the process was recovered with a recovery of 98.79% through Aspen simulated extractive distillation. Then the fixed investment

(equipment purchase and installation costs) for an annual production of 80 t GABA will be about 833000 USD; the total annual production cost (raw material cost and utility cost) will be about 641000 USD. The annual sale of GABA may be at the range of 2400000-4000000 USD and the payback period will be about 1-2 year. This integrated process provides a potential way for the industrial-scale production of food-grade GABA.