Recent progress on bio-succinic acid production from lignocellulosic biomass

Succinic acid is a valuable bulk chemical, which has been extensively applied in food, medicine, surfactants and biodegradable plastics industries. As a substitute for chemical raw material, bio-based succinic acid production has received increasing attention due to the depletion of fossil fuels and environmental issues. Meanwhile, the effective bioconversion of lignocellulosic biomass has always been a hot spot of interest owning to the advantages of low expense, abundance and renewability. Consolidated bioprocessing (CBP) is considered to be an alternative approach with outstanding potential, as CBP can not only improve the product yield and productivity, but also reduce the equipment and operating costs. In addition, the current emerging microbial co-cultivation systems provide strong competitiveness for lignocellulose utilization through CBP. This article comprehensively discusses different strategies for the bioconversion of lignocellulose to succinic acid. Based on the principles and technical concepts of CBP, this review focuses on the progress of succinic acid production under different CBP strategies (metabolic engineering based and microbial co-cultivation based). Moreover, the main challenges faced by CBP-based succinic acid fermentation are analyzed, and the future direction of CBP production is prospected.