In vitro fermentation of gum acacia - impact on the faecal microbiota

Interest in the consumption of gum acacia (GA) has been associated with beneficial health effects, which may be mediated in part by prebiotic activity. Two doses of GA and fructooligosaccharide (FOS) (1 and 2%) were tested for their efficacy over 48 h in pH- and temperature-controlled anaerobic batch cultures inoculated with human faeces. Samples were taken after 0, 5, 10, 24 and 48 h of fermentation. The selective effects of GA (increases in Bifidobacterium spp. and Lactobacillus spp.) were similar to those of the known prebiotic FOS. The 1% dose of substrates showed more enhanced selectivity compared to the 2% dose. The fermentation of GA also led to SCFA production, specifically increased acetate after 10, 24 and 48 h of fermentation, propionate after 48 h and butyrate after 24 and 48 h. In addition, FOS led to significant increase in the main SCFAs. These results suggest that GA displays potential prebiotic properties.