Previous studies have suggested that ethanol is a fermentation product of microflora. However, it is unknown whether this ethanol production is elevated by intake of prebiotics. Prebiotics are considered to enhance the production of short-chain fatty acids (SCFAs) as a fermentation product of beneficial bacteria. In the present study, the effect of fructooligosaccharides (FOS) consumption on intestinal ethanol levels was investigated. Rats were fed a diet with or without 10% FOS for two weeks. Consequently, FOS intake significantly increased ethanol levels per gram of ileum and cecum digesta of the rats (3.5-fold and 1.9-fold, respectively, P<0.01). The numbers of cecum Bifidobacterium (producer of ethanol and lactate) were significantly increased by FOS intake (P<0.05) and correlated with the cecum ethanol levels per gram of cecum (r=0.626, P<0.05). FOS intake also led to a significant increase in the cecum levels of SCFAs, namely lactate, propionate and n-butyrate (P<0.05). Furthermore, ethanol levels were significantly correlated with lactate levels (r=0.691, P<0.01), but not with propionate or n-butyrate levels (r=0.449 and 0.493, respectively, P>0.05). The current study, to the best of our knowledge, is the first to indicate that FOS intake significantly increases the level of intestinal ethanol. Therefore, dietary FOS may affect the intestinal health status of animals by elevating their ethanol levels, without direct ethanol consumption.
Keywords: Bifidobacterium; ethanol; fructooligosaccharides; intestine; prebiotics; rat; short-chain fatty acids.