纤维床反应器在琥珀酸放线杆菌菌种选育中的应用

为提高琥珀酸放线杆菌对琥珀酸盐的耐受性，在微米尺度的黏胶纤维膜载体上固定琥珀酸放线杆菌并构建纤维床反应器，通过菌体对高盐浓度环境的适应性进化，选育出一株耐盐的高产菌株。结果显示，该菌株琥珀酸产量为38.4±3.14 g/L，比初始菌株提高了23.8%；在3 L发酵罐分别对进化前后的菌株进行补料分批发酵产琥珀酸的验证，发现进化后获得的菌株发酵62 h，产琥珀酸86.3 g/L，生产强度1.39 g/（L·h），糖酸转化率78.7%，相比原始菌株，进化后获得的菌株糖酸转化率提高14.2%，琥珀酸生产强度提高24.1%。
In order to improve the tolerance of Actinobacillus succinogenes to succinate，a microfibrous bed bioreactor with immobilized Actinobacillus succinogenes is constructed in this thesis. Through adaptive evolution，a stain with enhanced salt-tolerance and productivity was obtained with succinic acid concentration of 38.4±3.14 g/L，which was a 23.8% increase compared to the original strain. Fermentative production of succinic acid with both the original and the evoluted strains were conducted in a 3 L fermentor. A fed-batch strategy was used and after 62 h of fermentation，the concentration，productivity and yield of succinic acid was 86.3 g/L，1.39 g/（L·h） and 78.7%，respectively for the evolved strain. Compared to the original strain，the succinic acid yield and productivity increased by 14.2% and 24.1% for the evolved strain