Effect of Lactobacillus acidophilus bacteria and copper oxide nanoparticles on the tissues of male mice

Abstract

L. acidophilus is used in the food and pharmaceutical industries to improve the natural gut flora, which is related to human digestive health. It offers excellent therapeutic and pharmaceutical benefits due to its biological activity in producing bacteriocins that inhibit pathogenic bacteria, as well as its ability to bind to epithelial cells. This binding prevents the adhesion of intestinal bacterial pathogens through competitive exclusion. Therefore, this study aimed to isolate and identify strains of L. acidophilus from local yogurt and evaluate the inhibitory effect of the metabolites of these bacterial strains on the tissues of male mice infected with E. coli-induced diarrhea. This research was conducted in the laboratories of the Department of Life Sciences at Samarra University from September 1, 2025, to November 1, 2025. In this research , a strain of L. acidophilus, a lactic acid bacteria, was obtained. The results showed that the metabolites of this strain possess good efficacy in inhibiting the E. coli serotype causing diarrhea.    Histological sections were taken from 0% and 10% of mice with liver, intestinal, and kidney infections. Inflammatory cells infiltrated the subcutaneous layer due to anaerobic E coli bacteria. This resulted in congestion, hemorrhage, and infiltration of inflammatory cells into the intestinal epithelial layers, tissue necrosis, deterioration of the stratified squamous epithelium, increased number of dead cells in the external lumen, breakdown of the keratin layer, and a change in the appearance of the stratified squamous epithelium, giving it a fibrous appearance.