BiombalanceTM: A Specific Oligomeric Procyanidin-Rich Grape Seed Extract as Multifunctional Ingredient Integrating Antibacterial, Antioxidant, and Anti-Inflammatory Activities with Beneficial Gut-Brain Axis Modulation.

Polyphenols, as natural compounds abundant in plant-derived foods, have been recognised for their human health benefits. This study evaluates the multifunctional properties of BiombalanceTM (BB), a grape seed extract rich in oligomeric procyanidins, in various in vitro and in vivo models. BB was studied to assess (i) its antimicrobial effects in different bacterial species; (ii) its protective effects against oxidative and inflammatory stress in Caco-2 cells; and (iii) its effects in mice, which were fed a standard diet with or without BB at two different doses (BB1X and BB2X) to understand the impacts of BB on microbiota and gut homeostasis. BB selectively inhibited several bacterial species, including Staphylococcus aureus, Helicobacter pylori, and Blautia coccoides. In addition, BB protected Caco-2 cells against hydrogen peroxide (H2O2)-induced oxidative damage and lipopolysaccharide (LPS)-induced oxidative and inflammatory stress. In vivo, BB supplementation upregulated the expression of antioxidant and homeostasis genes in the colon, ileum, and liver, accompanied by dose-dependent changes in the gut microbiota composition. Functional predictions indicated favourable modulation of microbial metabolic pathways, including those involved in antioxidant capacity and glutamate degradation. Furthermore, BB positively influenced key gut-brain axis mediators, including GLP-1, the GLP-1 receptor, and NPY. These findings highlight the potential of BiombalanceTM to support health and gut-brain communication and to protect against oxidative and inflammatory stress in the gut.