The differential modulatory effects of on the gut microbiota of obese dogs and mice are associated with improvements in metabolic disturbances.

Obesity is a disease in humans and companion animals that can cause many chronic diseases. () is a dominant fungus in Fuzhuan tea. In this study, we aimed to investigate the possibility that may reduce diet-induced obesity by regulating the gut microbiota and measuring the differences in the gut microbiota of obese mice and dogs under supplementation. High-fat diet-fed C57BL/6J mice and beagle dogs were supplemented with live for 8 or 12 weeks. Faecal microbiota transplantation (FMT) and 16S rRNA sequencing were used to evaluate the relationship between the anti-obesity effect of and the gut microbiota. The results suggested that live reduced obesity and metabolic disorders in obese mice and dogs. 16S rRNA sequencing results revealed that decreased the Firmicutes/Bacteroidetes (F/B) ratio and the abundance of members of the Firmicutes phylum, including , , and , in obese mice, but the opposite was true in obese dogs. Furthermore, to investigate whether the antiobesity effect of can be attributed to gut microbiota, FMT and 16S rRNA sequencing were employed. The FMT trial confirmed that the anti-obesity effect of was mediated by modulating gut dysbiosis. In addition, we isolated live from faeces and found the β-hydroxy acid metabolite of monacolin K (MKA) in culture. Our research implies that has the potential to treat obesity as a novel probiotic.