Disclosing the effects of pea-derived proteins on the human gut microbiota

Aim: Plant-derived proteins have emerged as promising alternatives to animal-based proteins, offering not only environmental and nutritional benefits to the human host but also potential effects on the gut microbiota. Yellow pea (Pisum sativum) represents an attractive source due to its balanced amino acid composition and suitability for food applications. This preliminary study was designed to evaluate the effects of two commercial pea-derived protein preparations - a wet-extracted protein isolate (PPI) and a dry-fractionated protein concentrate (PPC) - on the human gut microbiota using a dual in vitro approach. Methods: We combined monoculture assays on selected representative intestinal bacterial strains with in vitro cultivation models of stabilized microbial communities derived from human fecal samples. Results: Monoculture experiments revealed selective growth responses in certain taxa, such as Bacteroides thetaiotaomicron and Bifidobacterium spp. Moreover, in silico genomic predictions of amino acid biosynthesis and proteolytic capabilities further supported these findings, highlighting functional differences among the tested strains. Furthermore, analysis based on stabilized microbial communities revealed moderate shifts in microbial richness and composition. Notably, PPC was associated with greater variation in taxonomic profiles across samples. Both protein ingredients exhibited similar directional effects on specific taxa, including increases in the load of Bifidobacterium longum and Faecalibacterium duncaniae, and decreases in members of Bacteroides, Parabacteroides, and Phocaeicola. Conclusion: These findings indicate that pea-derived proteins, especially when used as concentrates, exert selective pressure on gut microbial communities.