Gas Fermentation of Chemicals

Abstract

The demand for alternative energy, materials, and technology to petrochemistry has been increasing due to environmental threats such as global warming. Here, we introduce microbial gas fermentation as a candidate technology to meet the demand. Gas fermentation can utilize syngas to produce valuable chemicals. Syngas is derived from biomass gasification and composed of mainly hydrogen and carbon monoxide. The gasification process can utilize any organic materials, including recalcitrant lignin and other organic wastes. Hence, it can contribute to solving the issue by utilizing carbon neutral resources and recycling various materials. In addition, gas fermentation can utilize carbon dioxide by supplementing hydrogen derived from renewable energy. The utilization of such gaseous substrates can be accomplished by a group of microorganisms called acetogen. We describe the metabolic pathway to utilize gaseous substrates, show some examples of the chemical production, and discuss the future perspective.