Biobutanol.

China initiated its acetone-butanol-ethanol (ABE) industry in the 1950s; it peaked in the 1980s, and ended at the end of the last century owing to the development of more competitive petrochemical pathways. However, driven by the high price of crude oil and environmental concerns raised by the over-consumption of petrochemical products, biofuels and bio-based chemicals including butanol have garnered global attention again. Currently, butanol produced from ABE fermentation is mainly used as an industrial solvent or a platform chemical for several bulk derivatives, and is also believed to be a potential biofuel. A number of plants have been built or rebuilt in recent years in China for butanol production with the ABE process. Chinese researchers also show great interest in the improvement of the production strains and corresponding processes. They have applied conventional mutagenesis methods to improve butanol-producing strains such as the Clostridium acetobutylicum mutant strains EA2018 (butanol ratio of 70%) and Rh8 (butanol tolerance of 19 g/L). The omics technologies, such as genome sequencing, proteomic and transcriptomic analysis, have been adapted to elucidate the characteristics of different butanol-producing bacteria. Based on the group II intron method, the genetic manipulation system of C. acetobutylicum was greatly improved, and some successful engineering strains were developed. In addition, research in China also covers the downstream processes. This article reviews up-to-date progress on biobutanol production in China.