Comparative analysis of fermented barley dietary fiber by Lactiplantibacillus plantarum dy-1 promoting gut health and regulating hepatic energy metabolism in high fat diet induced obese mice

Abstract

Previous study has revealed that Lactiplantibacillus plantarum (Lp. plantarum) dy-1 fermentation changed the structural and the in vitro fecal fermentation characteristics of barley dietary fiber. However, the health-promoting effects of fermented dietary fiber in vivo remained uncovered. This study aimed to compare the ameliorative effects of barley dietary fiber fermented with or without Lp. plantarum dy-1 on the lipid metabolism, gut microbiota composition and hepatic energy metabolism. After twelve weeks intervention, fermented barley dietary fiber (FBDF) could reduce the body weight and fat accumulation in liver and epididymal white adipose tissue, improve HFD-induced hyperlipidemia and glucose intolerance, and increase the short chain fatty acid (SCFA) levels, which the effects were better than those of raw barley dietary fiber (RBDF). FBDF supplementation improved the gut microbiota composition, especially enhanced the abundance of probiotic and SCFA-producing bacteria, such as Akkermansia, Muribaculaceae, et al, while RBDF exhibited regulatory effects on harmful bacteria (Escherichia–Shigella and Desulfovibrionacea). Additionally, FBDF up-regulated the expression of genes related to energy metabolism such as aerobic respiration and oxidative phosphorylation, inhibited the genes related to lipid biosynthetic metabolism, and improved the activities of hepatic energy metabolism-related enzymes, which the effects were better than those of RBDF. Therefore, this study indicated the potential of using FBDF as health food resources to prevent obesity or as the prebiotics to improve gut microbiota.