Antibacterial diarrhea effect and action mechanism of Portulaca oleracea L. water extract based on the regulation of gut microbiota and fecal metabolism

Portulaca oleracea has served as food and folk medicine in many parts of the world for thousands of years. Portulaca oleracea extract (POE) was prepared from fresh plants. This study aims to evaluate the antibacterial diarrhea effect and explore the possible mechanism.POE was effective in reducing diarrhea rate, improving intestinal tissue, and reducing cytokines concentrations of interleukin (IL)-6, IL-10, IL-12 p40 and TNF-α in blood. Besides, the result of histological observation showed that the mucus layer thickness and crypt length in the POE-treated group was higher than that in the model group. The POE could significantly upregulate the protein expression of MUC2, occludin and ZO-1. 16S rRNA sequencing analysis showed that Parabacteroides, Clostridium and Muribaculaceae may be the key functional microflora of POE. The non-targeted metabolomics also suggested that the antibacterial diarrheal effects of P. oleracea may be attributed to the regulation of amino acid metabolism and composition of the gut microbiota.Portulaca oleracea has definite clinical efficacy against bacterial diarrhea and anti-inflammatory effects. Its regulation of gut microbiota and fecal metabolism may account for its antibacterial diarrhea and anti-inflammatory effects. © 2023 Society of Chemical Industry.