氧供应量对Klebsiella pneumoniae利用混合糖生物合成2,3-丁二醇过程的影响分析

以筛选的肺炎克雷伯氏茵（Klebsiella pneumoniaeUV-86）为对象，考察供氧条件分别对茵体生长、葡萄糖和木糖双底物利用和产物合成的影响。研究发现生物量随氧供应量增加而增加。不同供氧条件对茵体消耗葡萄糖过程的影响较小，而代谢木糖的能力随氧供应量的增大而增强。微氧条件下2，3-丁二醇的生物合成能力最强，2，3-丁二醇产量在1．5wm下达到最高为30．1g／L，是好氧时的2．5倍，最大体积产率为0．485g／（L·h）。不同条件下两底物产物分布有所区别，木糖代谢中乙酸生产增强。因此根据不同阶段代谢特点选择适合的供氧策略可以提高过程产量和产率。

Analysis of 2,3-butanediol production with Klebsiella pneumoniae using sugar mixture under different oxygen supply conditions

The characteristics of cell growth, the metabolism of glucose and xylose and products formed by Klebsiella pneumoniae UV-86 （K. pneumoniae UV-86） under different oxygen supply conditions were investigated. The results showed that the cell mass increased with oxygen supply rates. The influence on the ability of glucose metabolism was not evident under different oxygen supply conditions. But the average specific xylose consumption rate was enhanced with increasing oxygen supply rates. The optimal production condition was under micro-aerobic condition. The maximum of 2, 3-butanediol concentration of 30.1 g/L was obtained at 1.5 vvm and it was 2.5 times the aerobic condition. The maximum productivity was 0. 485 g]（L＂ h）. The distributions of products metabolized by glucose and xylose under differ- ent oxygen supply conditions were different. The production of acetate was enhanced in xylose metabolism. Therefore, it was necessary to choose suitable strategies to improve 2,3-butanediol concentration and productivity according to metabolic characteristics at different stages.