Purpose : Inflammatory bowel disease (IBD) is characterized by inflammation and permeability increased of the intestinal wall leading to diarrhea, abdominal pain, weight loss, eg. Various treatments nowadays allow patients to treat symptomatic attacks and to a lesser extent, to space them out. These treatments are effective but remain burdensome for the patients with numerous undesirable effects and considerably alter their quality of life. Our new vegetable extract (NE) based on natural anti-inflammatory polymers has been developed as nutritional formulation in order to improve benefit/risk ratio, and thus reduce the use of current treatments to preserve the quality of life and mobility of IBD patients. Aims of this work were 1/ to assess the toxicity and inflammatory response of NE (pathway and responsible composition) on cells culture and mice models and 2/ to determine the implication of NE in intestinal permeability and membrane integrity. NE composition has been studied (flavonoids, vitamin C, polyphenol…) by chemical dosages and evaluated on cellular metabolism in vitro. The different types of inflammatory mediators (inflammatory cytokines) were determined by ELISA assay, and the treatment action on NF-kB pathway was determined after induction of inflammation by lipopolysaccharides (LPS) on Raw 264.7 cells by western blot. The proof of concept was evaluated in vivo on Fvb/n mice models treated with DSS representative of IBD pathologies. Secondly, the modification of permeability (in vitro and ex vivo) in IBD context was evaluated with NE treatment. The efficacy of the in vitro and in vivo treatments shows a decrease in inflammatory factors and inhibition of NF-kB pathway as well as a reduction of the digestive permeability system, particularly at the colonic level. The formulation of a nutritional vector based on natural excipient NE could be an effective therapeutic solution to treat IBD.