Contrasting Effects of Probiotic Yogurt and Brown Yogurt on the Urinary Metabolites and Gut Microbial Function of...

Consuming yogurt is beneficial for healthy people, but few studies have evaluated the interactions among yogurt intake, gut microbiota, and the metabolism of healthy hosts. We aimed to compare the effects of probiotic yogurt (Yi Jun Duo; YJD) and brown yogurt (Shao Suan Nai; SSN) on urinary metabolite concentrations and gut microbial composition and function in healthy adults. The SSN was produced by Streptococcus thermophilus S4.02 and low-fat (1.2%) milk, which was hydrolyzed using galactosidase and browned, and the YJD was whole milk fermented by a mixture of Lactobacillus bulgaricus, S. thermophilus, L. acidophilus, and Bifidobacterium lactis. Forty-six healthy adults (n = 23/group) consumed the yogurts for 28 days. NMR metabolomics was then used to study the differences in the concentrations of urinary metabolites, and the composition of the intestinal microbiota was characterized using 16S rRNA amplicon sequencing. SSN consumption significantly increased the urinary concentrations of methylamine, O-phosphocholine, trimethylamine N-oxide (TMAO), and 3-hydroxyisobutyrate, and reduced the abundances of the Pasteurellaceae, Enterobacteriaceae, Dorea, Megamonas, Haemophilus, and Shuttleworthia. YJD consumption reduced the concentrations of O-phosphocholine, fumarate, and tryptophan, reduced the abundance of Collinsella, and increased the urea concentration and the abundances of the Porphyromonadaceae and Parabacteroides. Twelve metabolites differed significantly in concentration between the two groups. SSN and YJD also had differing effects on carbohydrate metabolism (pyruvate metabolism, TCA cycle, and glycolysis/gluconeogenesis) and the amino acid metabolism pathway (phenylalanine, tyrosine, and tryptophan biosynthesis, and metabolism of histidine and tyrosine), principally by regulating the TMAO and amino acid metabolism of the intestinal bacteria.