Bioconversion properties of the urate-lowering probiotic fermented Aronia melanocarpa (black chokeberry) and its antihyperuricemic capacity via regulating metabolic/immune pathways and gut microbiota

Hyperuricemia (HUA) is a worldwide metabolic disorder. We developed a functional fermented beverage by fermenting Aronia melanocarpa (AR) with the urate-lowering probiotic Lactobacillus paracasei N1115 (LP). Firstly, untargeted metabolomics revealed that LP balanced its aroma and imparted a lactic flavor to AR and increased the concentrations of certain compounds with anti-HUA properties (e.g., caffeic acid and shikimic acid). In HUA mice, AR, fermented AR (FAR) and sterilized FAR (FARS) reduced serum uric acid, improved renal function, and suppressed inflammation via the TLR4/MyD88/NF-κB pathway. They also down-regulated the levels of XOD, ADA and URAT1. The fermented beverage showed superior efficacy, enhancing XOD inhibition by about 30% and additionally inhibiting GLUT9. FAR and FARS increased fecal butyrate, likely by enriching Faecalibaculum and Anaerostipes. Because the anti-HUA patterns of FAR and FARS were similar, and no colonization of Lactobacillus was observed, the postbiotics may serve as the primary factors contributing to the enhanced anti-HUA activity of the fermented beverage.