Novel anaerobic digestion induced by bacterial components for value-added byproducts from high-loading glycerol

Abstract

A novel bioprocessing system was developed and tested that involved anaerobic fermentation to degrade high-loading glycerol by a fermentation promoter, and which could be used for the production of important resources. In the absence of a promoter, there was no anaerobic digestion when glycerol (4.0–6.0%, v/v) was added to the reactor. By contrast, glycerol was readily decomposed when sewage sludge, acting as a fermentation promoter, was added to the anaerobic reactor. Fermentation resulted in the generation of hydrogen, 1,3-propanediol (1,3-PDO) and various organic acids. In 7days, glycerol decomposition reached 88%; hydrogen production was 3.1mg/kg-glycerol (0.0004g/day/L), and 1,3-PDO yield reached 0.35kg/kg-glycerol (0.05g/day/L). Further experiments confirmed that the bacteria Escherichia coli and particularly Schizosaccharomyces pombe (found within sewage sludge) and especially glucose (found within bacterial components (i.e., cell walls)) acted as efficient promoters of fermentation.