Phenolic compounds' impact on gut microbiota: insights from in vitro batch fecal fermentation for composition modulation

The relationship between phenolic compounds and gut microbiota (has been widely studied to explore the health benefits of these bioactive dietary compounds. Phenolic compounds are metabolized by gut microbiota, while also modulating its composition. However, the individual effects of these compounds on human gut microbiota remain underexplored. To address this, three phenolic compouds—ellagic acid, naringenin, and phloroglucinol—underwent in vitro batch fermentation with fecal samples from healthy donors. Samples were analyzed through 16S metagenomics sequencing, and short-chain fatty acids (SCFAs) were measured using gas chromatography. Results showed that ellagic acid and phloroglucinol had prebiotic properties, producing SCFAs like acetic, propanoic, and butyric acids and promoting the growth of beneficial bacteria such as Lactobacillus and Bifidobacterium. In contrast, naringenin was linked to the growth of pathogenic genera like Escherichia and Salmonella. This study provides valuable insights into how specific phenolic compounds influence gut microbiota composition, contributing to potential pharmaceutical or nutraceutical developments.