Wei Dong, Gu Jinjie, Zhang Zhongxi, Wang Chenhong, Wang Dexin, Kim Chul Ho, Jiang Biao, Shi Jiping, Hao Jian
Lab of Biorefinery, Shanghai Advanced Research Institute, Chinese Academy of Sciences; University of Chinese Academy of Sciences.
Lab of Biorefinery, Shanghai Advanced Research Institute, Chinese Academy of Sciences.
J Vis Exp. 2017 Jun 29(124):55828. doi: 10.3791/55828.
Bamboo is an important biomass, and bamboo hydrolysate is used by Klebsiella pneumoniae as a feedstock for chemical production. Here, bamboo powder was pretreated with NaOH and washed to a neutral pH. Cellulase was added to the pretreated bamboo powder to generate the hydrolysate, which contained 30 g/L glucose and 15 g/L xylose and was used as the carbon source to prepare a medium for chemical production. When cultured in microaerobic conditions, 12.7 g/L 2,3-butanediol was produced by wildtype K. pneumoniae. In aerobic conditions, 13.0 g/L R-acetoin was produced by the budC mutant of K. pneumoniae. A mixture of 25.5 g/L 2-ketogluconic acid and 13.6 g/L xylonic acid was produced by the budA mutant of K. pneumoniae in a two-stage, pH-controlled fermentation with high air supplementation. In the first stage of fermentation, the culture was maintained at a neutral pH; after cell growth, the fermentation proceeded to the second stage, during which the culture was allowed to become acidic.
竹子是一种重要的生物质，肺炎克雷伯菌将竹水解产物用作化学生产的原料。在此，竹粉用氢氧化钠预处理并洗涤至中性pH值。向预处理的竹粉中添加纤维素酶以生成水解产物，该水解产物含有30 g/L葡萄糖和15 g/L木糖，并用作制备化学生产培养基的碳源。在微需氧条件下培养时，野生型肺炎克雷伯菌产生12.7 g/L 2,3-丁二醇。在需氧条件下，肺炎克雷伯菌的budC突变体产生13.0 g/L R-乙偶姻。肺炎克雷伯菌的budA突变体在高空气补充的两阶段pH控制发酵中产生了25.5 g/L 2-酮葡萄糖酸和13.6 g/L木糖酸的混合物。在发酵的第一阶段，培养物保持在中性pH值；细胞生长后，发酵进入第二阶段，在此期间培养物变为酸性。
