Optimization of pretreatment and fermentation processes to enhance the production of succinic acid from corn straw by Actinobacillus succinogenes

Abstract

The utilization of lignocellulosic resources through microbial fermentation to produce succinic acid is a green pathway that has been widely studied. Raw material pretreatment is a critical step that determines the efficiency of succinic acid production. This study focused on optimizing the pretreatment conditions of corn straw via response surface methodology, resulting in the maximum sugar yield and the lowest concentration of inhibitory compounds, such as furfural, in the hydrolysate after enzymatic hydrolysis. Under the optimal conditions of 145°C and 0.97 % acid, the yields of glucose and pentose (xylose + arabinose) were 75.2 % and 72.1 %, respectively, while the concentration of furfural was 0.87 g/L. Using the nondetoxification hydrolysate of corn straw as a substrate, Actinobacillus succinogenes M4, a strain with stress resistance, was employed to produce succinic acid. The production rate of succinic acid was 0.54 g/L/h, and the concentration was 54.2 g/L. This study provides important information for the industrial development of succinic acid production using lignocellulosic materials, which is highly important for reducing the dependence on oil and solving environmental problems.