Lentil extract and yeast fiber against E. coli in lab tests
What it found
In lab tests, a lentil extract reduced a diarrhea-causing E. coli toxin and calmed gut inflammation, while yeast fiber cut the bacteria's ability to stick to mucus and gut cells.
Neither product changed how much the bacteria colonized a complex mix of human gut microbes.
What they found
Animal and lab studies
Toxin production
The lentil extract lowered LT toxin levels in a dose-dependent way, with the effect starting at 0.065 g/L and toxin no longer detected above 1 g/L. Yeast cell walls had no effect on LT toxin levels at any dose tested.
Bacteria sticking to mucus
The lentil extract and yeast cell walls reduced ETEC adhesion to mucin beads by about 6-fold and 3-fold, respectively. Only yeast cell walls reduced adhesion to mucus-secreting intestinal cells, by nearly one log.
Inflammation in gut cells
ETEC infection triggered inflammatory cytokine genes in intestinal cells. The lentil extract significantly reduced IL-1 beta, IL-6 and IL-10 induction, and lowered IL-8 protein levels back to near normal, while yeast cell walls only reduced IL-10.
Gut barrier strength
Both products strengthened the intestinal barrier in lab tests. Yeast cell walls reduced caffeine absorption from 21.2% to 17.0% and both products strongly reduced atenolol absorption, while the lentil extract raised electrical resistance across the cell layer.
Studies in people and animals
Colonization in gut microbes
In batch experiments with fecal samples from six people, neither product significantly changed ETEC levels in the liquid or mucus parts. Yeast cell walls showed a slight trend toward lower ETEC, but it was not significant.
Gut bacterial balance
In fecal batch tests, the donor person was the main factor shaping the gut bacterial community. ETEC infection also changed it, but the fiber products did not significantly affect the overall bacterial balance.
What the authors conclude
“These pioneering data demonstrate the promising role of dietary fibers in controlling different stages of the ETEC infection process.”
Also in their conclusions
- They say the lentil extract and yeast cell walls can interfere with the ETEC infection process at several stages, including virulence gene expression, cell adhesion, cross talk with intestinal host cells, and interactions with gut bacteria.
- They call for next steps in more complex models of the human gut before moving to animal studies.
- They say these findings have implications for how diet history may modify susceptibility to some gut infections and provide insights into using low-cost fiber products to help prevent ETEC infections and traveler's diarrhea.
How it was done
The authors wanted to find alternatives to antibiotics for traveler's diarrhea caused by ETEC, because antibiotic resistance is rising. They also noted that the anti-infectious properties of dietary fibers against gut pathogens have been poorly studied.
They tested a lentil extract and yeast cell walls against the human ETEC reference strain H10407 in lab dishes, including mucus-secreting intestinal cells and mucus beads. They also ran 24-hour batch experiments with fecal samples from six healthy people aged 20 to 30 to see how the fibers affected the bacteria in a complex gut microbe background.
What it can’t tell you
- These are lab tests using cells and fecal samples in dishes. They cannot show what happens in a living person.
- The products tested were not pure fibers, so other components may have caused some of the effects.
- The batch experiments used fecal samples from only six healthy people, so results may differ in other people.
Who paid
- Conflicts
- T.V.d.W. is advising ProDigest as a science officer and is a member of the scientific advisory board of MRM Health. S.B.-D. is advising NexBiome as a science officer. S.H. is an employee of HARi&CO. F.C.D. is an employee of Lallemand SAS. The other authors declare that the research was conducted in the absence of any commercial or financial relationships that could be considered as potential conflicts of interest.
- Authors work at
- Université Clermont Auvergne, France; Ghent University, Belgium
The paper
- Title
- Lentils and Yeast Fibers: A New Strategy to Mitigate Enterotoxigenic Escherichia coli (ETEC) Strain H10407 Virulence?
- Type
- Study
- Evidence
- Studies in people · animals · lab
- Summarised from
- Full text
- Cite
- Sauvaitre T, Van Herreweghen F, Delbaere K, et al (2022). Lentils and Yeast Fibers: A New Strategy to Mitigate Enterotoxigenic Escherichia coli (ETEC) Strain H10407 Virulence?. Nutrients. doi:10.3390/nu14102146Free full textPubMed 35631287DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error