Evaluation of peanut fermentation by gut microbes as a potential source of immunomodulatory metabolites
| dc.contributor.advisor | O'Mahony, Liam | |
| dc.contributor.advisor | O'Toole, Paul | |
| dc.contributor.author | Ndwandwe, Cebile Samkelisiwe | en |
| dc.contributor.funder | Science Foundation Ireland | en |
| dc.date.accessioned | 2026-09-17T14:40:23Z | |
| dc.date.available | 2026-09-17T14:40:23Z | |
| dc.date.issued | 2026-03-02 | |
| dc.date.submitted | 2026-03-02 | |
| dc.description.abstract | The metabolism of dietary substrates by the gut microbiota is important for generation of metabolites that have effects on immune function. Peanut consumption in early life has been shown to protect from later life allergy. The aim of this study was to investigate the effects of peanut fermentation by gut microbes. Blautia has been shown to be increased by peanut consumption so firstly Blautia utilization of potential substrates was assessed. Blautia wexlerae and Blautia obeum grew well on a variety of potential substrates, with some evidence of glycerol utilisation, indicating the existence of vitamin B12-dependent glycerol dehydratase genes. However, Blautia faecis was much more limited in its capacity to utilise these substrates with a much more selective carbohydrate utilisation profile. Using human faecal microbiota bioreactors, peanut was fermented by the faecal microbiota with significant beneficial microbiological and metabolic outcomes. Peanut fermentation generated high levels of SCFAs (including acetate, propionate and butyrate), with enriched pathways for lipid and aromatic amino acid metabolism. Raw peanut fermentation was associated with increased relative abundance of SCFA producers such as Bacteroidetes and Bifidobacteria. However, fermentation also led to histamine production. Fermentation of digested peanut led to increased anti-inflammatory metabolites including jasmonic acid, while decreasing pathogenic Escherichia-shigella and increased SCFA producers such as Bifidobacteria and Bacteroidetes. Metabolomic patterns in general suggested increased production of potential immunomodulatory metabolites. On the other hand, defatted peanut produced the lowest levels of SCFAs and increased relative abundance of opportunistic pathogens Escherichia-shigella, indicating a trend towards less favourable gut ecological environments. This work highlights the functional diversity of Blautia species, with species specific utilisation of a wide range of growth substrates. In addition, these findings illustrate how gut microbial fermentation of foods such as peanuts affects microbial composition and metabolism, with production of immunomodulatory compounds. The impact of food processing methods was also demonstrated as many potential beneficial effects were lost for defatted peanut. While my research clearly demonstrates that peanut can be metabolized by gut microbes, future research should determine the effects of microbial peanut fermentation on host immune responses, such as animal models of food allergy. | en |
| dc.description.status | Not peer reviewed | en |
| dc.description.version | Accepted Version | en |
| dc.format.mimetype | application/pdf | en |
| dc.identifier.citation | Ndwandwe, C. S. 2026. Evaluation of peanut fermentation by gut microbes as a potential source of immunomodulatory metabolites. MRes Thesis, University College Cork. | |
| dc.identifier.endpage | 100 | |
| dc.identifier.uri | https://hdl.handle.net/10468/19282 | |
| dc.language.iso | en | en |
| dc.publisher | University College Cork | en |
| dc.relation.project | info:eu-repo/grantAgreement/MSM/ED/ED1.100/02/0123/CZ/St. Anne´s University Hospital Brno - International Clinical Research Center (FNUSA-ICRC)/ | |
| dc.rights | © 2026, Cebile Ndwandwe. | |
| dc.rights.uri | https://creativecommons.org/licenses/by-nd/4.0/ | |
| dc.subject | Immunomodulatory metabolites | en |
| dc.subject | Peanut allergy | en |
| dc.subject | Food processing | en |
| dc.subject | Gut micriobiota | en |
| dc.subject | Blautia | en |
| dc.subject | Short-chain fatty acids (SCFAs) | en |
| dc.subject | Peanut fermentation | en |
| dc.subject | Histamine production | en |
| dc.subject | Faecal microbiota bioreactors | en |
| dc.title | Evaluation of peanut fermentation by gut microbes as a potential source of immunomodulatory metabolites | |
| dc.type | Masters thesis (Research) | en |
| dc.type.qualificationlevel | Masters | en |
| dc.type.qualificationname | MRes - Master of Research | en |
