Connection of the publication with planned research works.The publication is part of the planned scientific topic of the Department of Microbiology, Virology and Immunology of ONMedU, «Development of antimicrobial biomaterials based on natural polymers and quaternary ammonium compounds», the Department of Traumatology and Orthopedics of ONMedU «Intramedullary osteosynthesis for fractures of the lower third of the thigh» and the scientific topic of the Department of Urology, subject of scientific topic № 624p «The role of cellular and tissue metabolism in the diagnosis, clinical course and treatment of diseases of the kidneys, urinary tract and genital organs» (state registration number 0121U108881).Introduction.Ulcerative colitis (UC) is an inflammatory disease that generally affects the colon and rectum. Genetic factors, disorders of the host's immune system, dysbiosis of the intestinal microbiota, and environmental factors significantly affect the pathogenesis of UC [1,2].According to several authors, it has been established that UC is caused by an imbalance between the intestinal microbiota and the immunity of the mucous membrane, which directly leads to the activation of the inflammatory process in the intestine. With UC, the permeability of the mucous membrane increases, and the inflammatory reaction is caused by an excessive reaction below the lymphoid tissue [2, 3]. There is impaired colonic barrier function, decreased mucin and mucin-producing goblet cells, and decreased epithelial NLRP6 in UC patients [4].In patients with UC, the intestinal microbial population, its functional diversity and the stability of intestinal bacteria are disturbed with a decrease in the number of specific Firmicutes bacteria and an increase