精品文档---下载后可任意编辑高产 γ-氨基丁酸乳酸菌菌株选育及其转化条件优化的开题报告摘要：γ-氨基丁酸乳酸菌能够合成 γ-氨基丁酸（GABA），具有镇静、抗焦虑、改善睡眠等功效。本讨论旨在通过菌株选育和转化条件优化，提高 γ-氨基丁酸产量。首先，从酸奶和红枣中分离出 49 株乳酸菌，经过筛选和鉴定，最终选出一株能够高效产生γ-氨基丁酸的菌株。随后，通过单因素试验和响应面试验，确定了 γ-氨基丁酸产量最优的发酵条件为：pH4.5、温度 35℃、转速 150rpm、发酵时间 48 小时、初始浓度乳糖 10g/L、初始浓度谷氨酸 10g/L。最后，进一步优化了转化条件，发现添加谷氨酸酯和钙离子对 γ-氨基丁酸产量均有明显增加。本讨论对于提高 γ-氨基丁酸的产量和质量具有一定的参考价值。关键词：γ-氨基丁酸乳酸菌；菌株选育；转化条件优化Abstract：Gamma-aminobutyric acid lactobacillus can synthesize gamma-aminobutyric acid (GABA), which has sedative, anti-anxiety, and sleep improvement effects. The purpose of this study is to improve the production of GABA by strain selection and transformation condition optimization. Firstly, 49 strains of lactobacillus were isolated from yogurt and jujube, and after screening and identification, a strain that could efficiently produce GABA was finally selected. Subsequently, the optimal fermentation conditions for GABA production were determined by single-factor experiments and response surface experiments, which were pH4.5, temperature 35℃, rotation speed 150rpm, fermentation time 48 hours, initial lactose concentration 10g/L, and initial glutamic acid concentration 10g/L. Finally, the transformation conditions were further optimized and it was found that adding glutamic acid ester and calcium ions could significantly increase the production of GABA. This research has certain reference value for improving the yield and quality of GABA.Key words: Gamma-aminobutyric acid lactobacillus; strain selection; transformation condition optimization
