利用高通量生物反应器，以在线监测的pH为直接反馈补料信号，以葡萄糖、氨水和硫酸铵混合溶液为流加液进行补料发酵生产L-赖氨酸。当流加液中葡萄糖含量均为360 g/L时，对流加液中硫酸铵添加量、氨水添加量和发酵培养基接种量进行了单因素优化，确定一段式流加培养最佳条件为氨水添加量180 mL/L、硫酸铵添加量40 g/L、接种量为5 mL/45 mL培养基。分段式补料培养研究结果表明，在赖氨酸发酵的不同阶段采用不同配比的流加液进行分段式培养可以进一步提高赖氨酸的产酸浓度，同时降低残糖和残铵氮含量。三段式pH反馈补料发酵可以将赖氨酸产酸浓度提高到（56.85±0.98） g/L，与二段式和一段式相比分别提高8.65%和23.64%。%L-lysine fed-batch fermentations were carried out in high throughput bioreactors, and pH was used as a direct feedback signal to feed the solution mixed with glucose, ammonia water and ammonium sulfate. The single factor optimization experiments on addition amount of ammonia water, ammonium sulfate and inoculation quantity, when glucose level in feeding liquid was 360 g/L, were developed. The best composition of one section fermentation feeding liquid was ammonia water 180 mL/L, ammonium sulfate 40 g/L and inoculation quantity 5 mL/45 mL. The results of phased fed-batch showed that the yield of L-lysine was increased meanwhile the level residual sugar and ammonium was decreased, when feeding liquid with different composition was used at different fermentation stages. The production was enhanced by (56.85 ±0.98) g/L at the end of tri-section pH feedback fed-batch fermentation, which was increased by 8.65%and 23.64%respectively compared with bi-section and one section styles.
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