Potential for enriching next-generation health-promoting gut bacteria through prebiotics and other dietary components

Abstract

The human intestinal commensal microbiota and associated metabolic products have long been regarded as contributors to host health. As the identity and activities of the various members of this community have become clearer, newly identified health-associated bacteria, such as Faecalibacterium prausnitzii, Akkermansia muciniphila, Ruminococcus bromii and Roseburia species, have emerged. Notably, the abundance of many of these bacteria is inversely correlated to several disease states. While technological and regulatory hurdles may limit the use of strains from these taxa as probiotics, it should be possible to utilize prebiotics and other dietary components to selectively enhance their growth in situ. Dietary components of potential relevance include well-established prebiotics, such as galacto-oligosaccharides, fructo-oligosaccharides and inulin, while other putative prebiotics, such as other oligosaccharides, polyphenols, resistant starch, algae and seaweed as well as host gut metabolites such as lactate and acetate, may also be applied with the aim of selectively and/or differentially affecting the beneficial bacterial community within the gastrointestinal environment. The present review provides an overview of the dietary components that could be applied in this manner.

Keywords: Prebiotics; beneficial microbes; health-promoting gut bacteria; microbiota.

Figure 1.

Schematic representation of selected gut bacteria involved in carbohydrate fermentation and cross-feeding interactions resulting in the production of major microbial metabolites. Pathways leading to the production of the three main SCFAs, acetate, butyrate and propionate, are depicted here. Acetate can be produced from acetyl-CoA or by acetogens using H₂ and CO₂ or formate. It can also be used for the formation of butyrate. Butyrate can be formed in two ways; either through the formation of butyryl-P or more commonly through the use of butyryl-CoA:acetate CoA-transferase which many Firmicutes possess. The main route by which propionate is generated is via the succinate pathway. However, two other pathways have also been found; i.e., the acrylate pathway which involves lactate and the propanediol pathway which utilizes deoxyhexose sugars. DHAP, dihydroxyacetonephospate; PEP, phosphoenolpyruvate. Adapted from Louis et al., 2014.⁴³

Figure 2.

An overview of some beneficial impacts of prebiotic supplementation on the gut microbiota.