Biochemical Effect Mechanism of Probiotics in Gut and Evaluation of Their Effect on Allergies

Abstract

Probiotics are natural members of the gut microbiota. In order to be effective, they must first pass through the intestinal tract alive by showing resistance to gastric acidity and bile salts, and finally colonize the cell surfaces of the intestinal epithelium. The limitation of allergy treatment methods has paved the way for the use of probiotics for the development of alternative treatment applications. However, in order for probiotics to be used in the treatment of allergic diseases, first of all, the biochemical effect mechanism in the gastrointestinal system (GIS) should be fully understood and a hypothesis consisting of three steps has been proposed for this purpose. The first step of the mechanism is that probiotics reduce the number of pathogenic bacteria and they do this by producing antimicrobial metabolites as a result of their activities in the GIS and showing antagonistic effect against other microorganisms. The second step of the mechanism is competition for nutrients, colonization sites and adhesion to intestinal epithelial tissue. The third step of the mechanism is that they change the enzymatic activity, and they do this by producing digestive system enzymes and thus contributing to the epithelial barrier functions of the intestinal tissues. Some people's immune system may also react to substances that are not normally harmful, and IgE antibodies are formed against these allergens, especially as a result of the system's repeated encounters with these allergens, and the findings of this hypersensitivity process indicate allergies. Probiotics act on the GIS by providing intestinal modulation with their dominant colonies in the intestines and stimulate mucosal immunity. They enhance the host immune system and the mucus barrier system by interacting with immune cells in the small intestine and large intestine. Both systemic and local-mucus immune systems can be regulated by probiotics in the GIS. In conclusion, probiotics show beneficial effects by regulating the microbial balance of the GIS.