Effects of golden oyster mushroom extract on oral and gut microbiota diversity in rats

Background Golden oyster mushroom (GOM) exhibits various beneficial effects. However, it remains unknown whether it can simultaneously affect both the oral and gut microbiomes. Therefore, we investigated the effects of GOM-containing diets on the oral and gut microbiomes of rats. Methods We determined the minimum inhibitory concentration of GOM against periodontal disease-related bacteria. We randomly categorized the rats into two groups receiving a standard diet only (control) or a standard diet containing 5% GOM (GOM). We analyzed the microbiota using bacterial DNA isolated from oral swabs and fecal samples and through 16S ribosomal RNA sequencing. Moreover, we assessed G protein-coupled receptor ( Gpr ) 41 and Gpr43 mRNA expression in the gut tissue. Results GOM inhibited the growth of Fusobacterium nucleatum . Although the α- or β-diversity of the oral microbiome exhibited no significant differences, the gut microbial β-diversity significantly differed between the two groups. Pathways related to fatty acid and lipopolysaccharide synthesis were inhibited in the oral microbiome of GOM-fed rats compared to those in the control group. Moreover, Gpr41 expression was increased in GOM-fed rats, indicating enhanced short-chain fatty acid production in the gut. Conclusion GOM may help prevent various diseases and support oral and gut microbiome health.