Led by veteran prebiotic researcher, Kristin Verberke, PhD, from the Leuven Food Science and Nutrition Research Center in Belgium, the review suggests that examining protein fermentation metabolites like phenol, p-cresol, indole and ammonia could be valuable markers of prebiotic health benefits as they occur in small quantities in the microbiome.
The idea being that “analysing the activity of the microbiota rather than its composition and structure may be more relevant to assess the impact of prebiotic interventions.”
Consequently, changes in bacterial fermentation metabolites could be valuable markers of prebiotic health benefits, for instance the decrease in protein fermentation metabolites that are typically considered as potentially toxic (like phenol, p-cresol, indole, ammonia). According to the review, these metabolites occur at non-toxic concentration ranges in the colon, which means examining a decrease would be not sufficient to conclude a health benefit.
“The endproducts of saccharolytic fermentation, SCFA, may have effects on colonic health, host physiology, immunity, lipid and protein metabolism and appetite control. However, measuring SCFA concentrations in faeces is insufficient to assess the dynamic processes of their nutrikinetics,” wrote professor Verbeke and her colleagues in Nutrition Research Reviews.
They added: “Integration of results from metabolomics and metagenomics holds promise for understanding the health implications of prebiotic microbiome modulation but adequate tools for data integration and interpretation are currently lacking. Similarly, studies measuring metabolite fluxes in different body compartments to provide a more accurate picture of their nutrikinetics are needed.”
“The ultimate goal is to move towards a definition of ‘healthy metabolic signatures’ that might comprise integrated measures of metabolite patterns in different matrices.”
Prebiotic effects are typically measured by changes in probiotic species Bifidobacterium and Lactobacillus in faeces and the microbiome.
Metagenomics is the genomic analysis of microorganisms.
Prebiotic fibres typically include oligofructose and inulin.
Nutrition Research Reviews
2015 Jun;28(1):42-66. doi: 10.1017/S0954422415000037
‘Towards microbial fermentation metabolites as markers for health benefits of prebiotics’
Authors: Verbeke KA, Boobis AR, Chiodini A, Edwards CA, Franck A, Kleerebezem M, Nauta A, Raes J, van Tol EA, Tuohy KM