Abstract：
γ-Aminobutyric acid (GABA) is a crucial neurotransmitter with wide application prospects. In this study, we focused on a GABA-producing strain from a traditional Chinese fermented beverage system. Among the six isolates, Lactobacillus hilgardii GZ2 exhibited the greatest ability to produce GABA in the traditional Chinese fermented beverage system. To increase GABA production, we optimized carbon sources, nitrogen sources, temperature, pH, and monosodium glutamate and glucose concentrations and conducted fed-batch fermentation. The best carbon and nitrogen sources for GABA production and cell growth were glucose, yeast extract and tryptone. Gradual increases in GABA were observed as the glucose and monosodium glutamate concentrations increased from 10 g/L to 50 g/L. During fed-batch fermentation, lactic acid was used to maintain the pH at 5.56, and after feeding with 0.03 g/mL glucose and 0.4 g/mL sodium glutamate for 72 h, the GABA yield reached 239 g/L. This novel high-GABA-producing strain holds great potential for the industrial production of GABA, as well as the development of health-promoting functional foods and medical fields.
摘要：
γ-氨基丁酸(GABA)是一种重要的神经递质,具有广阔的应用前景。在这项研究中,我们专注于从传统的中国发酵饮料系统中产生GABA的菌株。在六个分离株中，在传统的中国发酵饮料体系中，木耳乳杆菌GZ2表现出最大的产生GABA的能力。为了增加GABA产量，我们优化了碳源，氮源，温度,pH值,和味精和葡萄糖浓度，并进行补料分批发酵。GABA生产和细胞生长的最佳碳源和氮源是葡萄糖，酵母提取物和胰蛋白胨。随着葡萄糖和味精浓度从10g/L增加到50g/L，观察到GABA逐渐增加。在补料分批发酵过程中，用乳酸维持pH为5.56,用0.03g/mL葡萄糖和0.4g/mL味精饲喂72h,GABA产量达到239g/L这种新型的高产GABA菌株在GABA的工业化生产中具有巨大的潜力，以及促进健康的功能性食品和医疗领域的发展。
