Development of an integrated process for the production of high-purityγ-aminobutyric acid from fermentation broth

摘要

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.