Antiobesity Effect of Lactiplantibacillus plantarum Fermented Barley Extracts via the Interactions with Gut Microbiota of the Obese Adult Humans

Abstract

Extracts of fermented barley with Lactiplantibacillus plantarumdy-1 (LFBE) have been reported to exert antiobesity activity in vivo and in vitro. However, whether it worked in clinical trials remained uncovered. In the current study, we conducted a single-blind experiment by enrolling on some obese adult humans with hyperlipemia to test the effects of products containing LFBE (No. ChiCTR1800019614 by the Chinese Clinical Trial Registry). Results indicated that LFBE intervention could ameliorate the symptoms of the obese, characterized by the decrease of body fat percentage, visceral fat area, and serum lipid levels. More interestingly, products containing the β-glucan ingredients had similar antiobesity effects. 16S rRNA sequencing revealed that LFBE modulated the community structure of the gut microbiota of the obese adults as shown by the diversity analysis. For gut microbiota composition, LFBE significantly increased the Bacteroides genus while decreasing Streptococcus and Haemophilus genus. At the species level, beneficial microorganisms such as Bifidobacterium_longum_subsp_longum, Alistipes_sp_AL-1, Bacteroides_plebeius, and Bacteroides_vulgatus were enriched by LFBE, which was different from the effects of β-glucan. Furthermore, Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis indicated that LFBE particularly regulated the steroid biosynthesis and hypertrophic cardiomyopathy pathways. Furthermore, correlation analysis suggested that body fat percentage and visceral fat area were significantly positively correlated with Desulfovibrio and Sutterella, the basal metabolic rate was negatively correlated with Haemophilus, and fasting blood glucose was positively correlated with Dialister. In all, this clinical study demonstrated the antiobesity function of LFBE in humans, probably via its interactions with the gut microbiota, and LFBE could be developed as a prebiotic ingredient with antiobesity effects for a healthy diet. This trial is registered with ChiCTR1800019614.