响应面试验优化产琥珀酸放线杆菌GXAS137发酵粗甘油产丁二酸工艺

通过优化产琥珀酸放线杆菌GXAS137发酵粗甘油产丁二酸的培养基，提高丁二酸产量，降低生产成本。先通过单因素试验对粗甘油发酵产丁二酸的电子受体、初始粗甘油质量浓度及氮源进行了优化，再利用响应面试验确定重要参数的最佳水平。结果表明：二甲基亚砜（dimethyl sulfoxide，DMSO）为最适电子受体，玉米浆可替换酵母粉作为氮源，各因素的最佳条件为：初始粗甘油质量浓度55.43?g/L、DMSO质量浓度10.35?g/L、玉米浆质量浓度17.69?g/L。优化后丁二酸产量达到37.02?g/L，丁二酸得率为66.79%，生产强度为0.51?g/（L·h）。与初始条件下丁二酸产量（16.88?g/L）相比，优化后提高了1.19?倍。本研究为微生物发酵粗甘油原料生产丁二酸提供了理论支持。

Optimization of Succinic Acid Production from Crude Glycerol by Actinobacillus succinogenes GXAS137 Using Response Surface Methodology

The optimization of medium components for improved succinic acid production by Actinobacillus succinogenes GXAS137 at reduced cost was performed using one-factor-at-a-time method and response surface methodology. The independent variables considered were electron acceptors, crude glycerol concentration and nitrogen sources. The results showed that dimethyl sulfoxide (DMSO) was the optimum electron acceptor and corn steep liquor (CSL) could be used as an alternative nitrogen source to replace yeast extract. The optimum culture medium that provided maximum succinic acid yield of 37.02 g/L, which was increased by 119% compared to that (16.88 g/L) before optimization, was composed of crude glycerol 55.43 g/L, DMSO 10.35 g/L and CSL 17.69 g/L. Under this optimized condition, the conversion rate of glycerol to succinic acid was 66.79% and succinic acid productivity was 0.51 g/(L·h). This study can provide a basis for the microbial production of succinic acid from crude glycerol.