A protocol for the cultivation and monitoring of ileal gut microbiota surrogates

J Appl Microbiol. 2022 Sep;133(3):1919-1939. doi: 10.1111/jam.15684. Epub 2022 Jul 15.

Abstract

Aims: This research aimed to develop and validate a cultivation and monitoring protocol that is suitable for a surrogate microbial community that accounts for the gut microbiota of the ileum of the small intestine.

Methods and results: Five bacterial species have been selected as representatives of the ileal gut microbiota and a general anaerobic medium (MS-BHI, as minimally supplemented brain heart infusion) has been constructed and validated against BCCM/LGM recommended and commercial media. Moreover, appropriate selective/differential media have been investigated for monitoring each ileal gut microbiota surrogate. Results showed that MS-BHI was highly efficient in displaying individual and collective behaviour of the ileal gut microbiota species, when compared with other types of media. Likewise, the selective/differential media managed to identify and describe the behaviour of their targeted species.

Conclusions: MS-BHI renders a highly efficient, inexpensive and easy-to-prepare cultivation and enumeration alternative for the surrogate ileal microbiota species. Additionally, the selective/differential media can identify and quantify the bacteria of the surrogate ileal microbial community.

Significance and impact of study: The selected gut microbiota species can represent an in vitro ileal community, forming the basis for future studies on small intestinal microbiota. MS-BHI and the proposed monitoring protocol can be used as a standard for gut microbiota studies that utilize conventional microbiological techniques.

Keywords: anaerobic cultivation; general anaerobic medium; gut microbiota; ileum; in vitro studies; monitoring protocol; small intestine.

MeSH terms

  • Bacteria / genetics
  • Gastrointestinal Microbiome*
  • Ileum / microbiology
  • Intestine, Small
  • Microbiota*