建立了以K.pneumoniae为菌种,甘油和半纤维素水解液(HH)共发酵生产1,3-丙二醇(1,3-PDO)的体系.通过添加HH,1,3-PDO的质量浓度、甘油的转化率和生产力比甘油单独发酵分别提高了18.2％,24.4％,18.0％.HH中的木糖和甘露糖能显著提高l,3-PDO的产量和生物量,葡萄糖对l,3-PDO的合成产生抑制,半乳糖和阿拉伯糖对l,3-PDO的合成没有影响.与不添加抑制物相比,添加0.28 g/L糠醛时,生物量提高了12％,1,3-PDO的产量有微量提高;添加0.61 g/L甲酸盐时,对细胞生长和1,3-PDO的合成产生轻微抑制,分别降低了9.8％和11％;添加1.46 g/L乙酸盐时,细胞生长略有提高,1,3-PDO的质量浓度从8.77 g/L增至11.73 g/L.在补料分批发酵中添加HH,1,3-PDO的质量浓度、甘油的转化率和生产力分别提高到71.58 g/L,65％,1.93 g/(L·h),比甘油单独发酵分别提高了17.8％,25.0％,17.7％.%A system for the synthesis of 1, 3-propanediol(l, 3-PDO) from glycerol and hemicellulose hydrolysates(HH) as the cosubstrate was established. By the addition of HH, the 1, 3-PDO mass concentration, glycerol conversion and productivity increased by 18.2%, 24.4% and 18.0% higher than those from glycerol alone, respectively. Xylose and mannose in HH enhanced the biomass and fermentation efficiency, glucose inhibited the 1, 3-PDO synthesis, and galactose and arabinose have no effect on the fermentation. By the addition of 0.28 g/L furfural, the biomass increased by 12% higher than that without any inhibitors; by the addition of 0.61 g/L formate, the cell growth and 1, 3-PDO production decreased 9.8% and 1.1% respectively; by the addition of 1.46 g/L acetate, the 1, 3-PDO mass concentration increased from 8.77 g/L to 11.73 g/L. With the addition of HH in fed-batch fermentation, the 1, 3-PDO mass concentration, glycerol conversion and productivity increased to 71.58 g/L, 65% and 1.93 g/(L·h), which were 17.8%, 25.0% and 17.7% higher than those from glycerol alone respectively.
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