以右旋糖酐发酵废液为原料发酵生产丁二酸

Fermentative succinic acid production from waste fermentation broth of dextran

以右旋糖酐发酵废液为原料利用琥珀酸放线杆菌发酵生产丁二酸,在比较不同糖浓度废液对发酵产酸影响的基础上,通过Plackett-Burman试验筛选出对摇瓶发酵产丁二酸的主要影响因素Na H2PO4·2H2O,并用单因素试验确定其最适质量浓度为2.8 g/L。在3 L发酵罐上进行分批发酵和补料分批发酵,以60 g/L初糖质量浓度的右旋糖酐发酵废液为碳源,分批发酵46.8 h产丁二酸40.5 g/L;采用30 g/L葡萄糖为起始发酵培养基的碳源,后续补加浓缩右旋糖酐发酵废液的方式进行补料分批发酵,丁二酸质量浓度达到55.0 g/L,生产强度1 g/(L·h),糖酸转化率为0.83 g/g。结果表明:以右旋糖酐发酵废液为原料发酵生产丁二酸,为解决废液处理排放提供了新途径,具有良好的应用前景。

In this paper,succinic acid production by Actinobacillus succinogenes from waste fermentation broth of dextran was studied. After comparing the effect of initial sugar concentrations on succinic acid production,PlackettBurman experiment was used to determine that Na H2PO4·2H2O was the most important factor in succinic acid production. Results from single factor experiment suggested that the optimal concentration of Na H2PO4·2H2O was 2. 8g / L for the following fermentation tests. Condensed waste fermentation broth of dextran with reducing sugar concentration of 60 g / L was used as the carbon source for batch fermentation in a 3 L fermentor,and 40. 5 g / L succinic acid concentration was achieved after 46. 8 h. In the fed-batch fermentation,an initial carbon source of 30 g / L glucose solution was added,followed by condensed waste fermentation broth of dextran,leading to an eventual succinic acid concentration of 55. 0 g / L with a productivity of 1 g /（ L·h） and conversion rate of 0. 83 g / g. This work not only provided a new and efficient way to produce succinic acid using cheap raw materials,but also offered a significant promising method for solving the problems of waste liquid emission.