Clostridium sp. Strain NJ4: A Promising Solventogenic Strain for Butanol Production from Jerusalem Artichoke through Consolidated Bioprocessing

Clostridium sp. strain NJ4 was successfully isolated and characterized, which exhibited a wide carbon utilization spectrum, including glucose, fructose, fructooligosaccharide, and Jerusalem artichoke. In comparison to 14.71 and 15.81 g L-1 butanol produced from glucose and fructose, a similar butanol production was obtained by strain NJ4 from fructooligosaccharide and Jerusalem artichoke without supplementation of exogenous inulinases, owing to its efficient expression of levanase and fructan beta-fructosidase. After the process optimization, 13.25 g L-1 butanol was directly produced from 90 g L-1 Jerusalem artichoke, indicating that strain NJ4 could be a promising candidate for butanol production from Jerusalem artichoke through consolidated bioprocessing (CBP) at a large scale. In addition, extra supplementation of sodium butyrate could improve butanol and acetone-butanol-ethanol titers to 14.35 and 24.75 g L-1. To the best of our knowledge, this represents the highest butanol production from Jerusalem artichoke through CBP.