In vitro batch cultures of gut microbiota from healthy and ulcerative colitis (UC) subjects suggest that sulphate-reducing bacteria levels are raised in UC and by a protein-rich diet

Int J Food Sci Nutr. 2014 Feb;65(1):79-88. doi: 10.3109/09637486.2013.825700. Epub 2013 Aug 13.

Abstract

Imbalances in gut microbiota composition during ulcerative colitis (UC) indicate a role for the microbiota in propagating the disorder. Such effects were investigated using in vitro batch cultures (with/without mucin, peptone or starch) inoculated with faecal slurries from healthy or UC patients; the growth of five bacterial groups was monitored along with short-chain fatty acid (SCFA) production. Healthy cultures gave two-fold higher growth and SCFA levels with up to ten-fold higher butyrate production. Starch gave the highest growth and SCFA production (particularly butyrate), indicating starch-enhanced saccharolytic activity. Sulphate-reducing bacteria (SRB) were the predominant bacterial group (of five examined) for UC inocula whereas they were the minority group for the healthy inocula. Furthermore, SRB growth was stimulated by peptone presumably due to the presence of sulphur-rich amino acids. The results suggest raised SRB levels in UC, which could contribute to the condition through release of toxic sulphide.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acids, Sulfur / adverse effects
  • Amino Acids, Sulfur / metabolism*
  • Butyric Acid / metabolism
  • Colitis, Ulcerative / diet therapy
  • Colitis, Ulcerative / metabolism
  • Colitis, Ulcerative / microbiology*
  • Colon / metabolism
  • Colon / microbiology*
  • Diet, Protein-Restricted
  • Dietary Proteins / administration & dosage*
  • Dietary Proteins / adverse effects
  • Dietary Proteins / metabolism
  • Fatty Acids, Volatile / metabolism*
  • Feces / microbiology
  • Female
  • Fermentation
  • Gram-Negative Bacteria / classification
  • Gram-Negative Bacteria / growth & development
  • Gram-Negative Bacteria / isolation & purification
  • Gram-Negative Bacteria / metabolism
  • Gram-Positive Bacteria / classification
  • Gram-Positive Bacteria / growth & development
  • Gram-Positive Bacteria / isolation & purification
  • Gram-Positive Bacteria / metabolism
  • Humans
  • Intestinal Mucosa / metabolism
  • Intestinal Mucosa / microbiology*
  • Male
  • Microbial Viability
  • Middle Aged
  • Molecular Typing
  • Mucins / metabolism
  • Peptones / metabolism
  • Starch / metabolism
  • Sulfur-Reducing Bacteria / classification
  • Sulfur-Reducing Bacteria / growth & development*
  • Sulfur-Reducing Bacteria / isolation & purification
  • Sulfur-Reducing Bacteria / metabolism

Substances

  • Amino Acids, Sulfur
  • Dietary Proteins
  • Fatty Acids, Volatile
  • Mucins
  • Peptones
  • Butyric Acid
  • Starch