Study on the regulatory effect of pomegranate peel polyphenols on rat metabolism and its mechanism mediated by gut microbiota.

Purpose: Pomegranate peel polyphenols (PPPs) have recognised bioactive properties, but their metabolic interactions with gut microbiota are still uncertain. Materials and methods: This investigation aimed to shed light on the metabolic regulation by PPPs and the gut microbiota's role in this process in normal SD rats. Animals were administered PPPs (300 mg/kg·bw·d) for 28 days. Results: Results showed PPPs significantly reduced rat body weight, and optimised lipid profiles. PPPs modulated the gut microbial composition by enhancing the abundance of beneficial bacterial genera (e.g. Oscillibacter, Prevotella_9) and stimulating the biosynthesis of short-chain fatty acids (SCFAs). Serum metabolomics further revealed that PPPs altered key metabolic pathways, including glycine metabolism, primary bile acid biosynthesis, and tryptophan metabolism. The correlation studies indicated that PPPs target specific gut bacterial genera (Oscillibacter, Allobaculum, Prevotella) to regulate SCFAs production and key metabolic pathways, thereby optimising the metabolic status of rats. Conclusions: These findings provide a critical scientific basis for their potential application in preventing metabolic disorders.