In vitro fermentation of B-GOS: impact on faecal bacterial populations and metabolic activity in autistic and non-autistic children

FEMS Microbiol Ecol. 2017 Feb;93(2):fiw233. doi: 10.1093/femsec/fiw233. Epub 2016 Nov 16.

Abstract

Children with autism spectrum disorders (ASD) often suffer gastrointestinal problems consistent with imbalances in the gut microbial population. Treatment with antibiotics or pro/prebiotics has been postulated to regulate microbiota and improve gut symptoms, but there is a lack of evidence for such approaches, especially for prebiotics. This study assessed the influence of a prebiotic galactooligosaccharide (B-GOS) on gut microbial ecology and metabolic function using faecal samples from autistic and non-autistic children in an in vitro gut model system. Bacteriology was analysed using flow cytometry combined with fluorescence in situ hybridization and metabolic activity by HPLC and 1H-NMR. Consistent with previous studies, the microbiota of children with ASD contained a higher number of Clostridium spp. and a lower number of bifidobacteria compared with non-autistic children. B-GOS administration significantly increased bifidobacterial populations in each compartment of the models, both with autistic and non-autistic-derived samples, and lactobacilli in the final vessel of non-autistic models. In addition, changes in other bacterial population have been seen in particular for Clostridium, Rosburia, Bacteroides, Atopobium, Faecalibacterium prausnitzii, Sutterella spp. and Veillonellaceae. Furthermore, the addition of B-GOS to the models significantly altered short-chain fatty acid production in both groups, and increased ethanol and lactate in autistic children.

Keywords: B-GOS; SCFAs; autism; gut microbiota; in vitro fermentation; prebiotics.

MeSH terms

  • Anti-Bacterial Agents
  • Autistic Disorder / microbiology*
  • Bacteroides / metabolism
  • Bifidobacterium / growth & development
  • Bifidobacterium / metabolism
  • Child*
  • Clostridium / metabolism
  • Fatty Acids, Volatile / metabolism
  • Feces / microbiology*
  • Fermentation*
  • Humans
  • In Situ Hybridization, Fluorescence
  • Lactic Acid
  • Lactobacillus / metabolism
  • Microbiota
  • Oligosaccharides / metabolism
  • Prebiotics*

Substances

  • Anti-Bacterial Agents
  • Fatty Acids, Volatile
  • Oligosaccharides
  • Prebiotics
  • Lactic Acid