Chemical and microbial characterization for fermentation of water-soluble cellulose acetate in human stool cultures.

ABSTRACT

BACKGROUND: Water-soluble cellulose acetate (WSCA), a synthetic fiber source, was applied to human stool cultures and to pure cultures of representative Bacteroides species to characterize the fermentation properties of WSCA in the human gut, and to assess the potential availability of WSCA as a food or additive candidate. RESULTS: All nine of the different types of WSCA tested here provided increased acetate levels in human stool cultures. Greater levels of deacetylation were observed as the degree of substitution of hydroxyl groups by acetyl groups decreased. Among the nine tested types of WSCA, CA-0.78-128 caused the largest shifts of the microbial community, including an increased abundance of members of the genus Bacteroides, especially Bacteroides uniformis. Of four representative human gut Bacteroides species, only B. uniformis grew in pure culture on WSCA to produce acetate actively. CONCLUSION: Water-soluble cellulose acetate has the potential for dietary application in human and other monogastric animals, based on the enhanced production of short-chain fatty acids (SCFAs), in particular acetate, in the hindgut. Short-chain fatty acid production is caused by selective proliferation of specific gut bacteria belonging to the genus Bacteroides. © 2020 Society of Chemical Industry.