Lactobacillus is one of the commonly used probiotics in commercial products.27 Probiotics are increasingly used to prevent or treat a variety of intestinal diseases, including inflammatory bowel disease (IBD), acute infectious diarrhea, and antibiotic‐associated diarrhea.28 Here, we found that Lactobacillus administration effectively suppressed CA9 expression, protected against mucus depletion in murine colonic tissues following DEPs exposure. This evidence concerns the gene CA9 and inflammatory bowel disease.