Evaluation of the effects of fermented plant juices (PFJ) derived from corn, alfalfa, and meadow grass on gut microbiota profile in a diabetic mouse model

In this study, the effects of fermented plant juices (PFJs) obtained from corn, alfalfa, and meadow grass on the gut microbiota in a diabetic mouse model were evaluated using metagenomic methods. Thirty male Balb/c mice were divided into five groups (Control, Positive Control, Meadow Grass PFJ, Corn PFJ, and Alfalfa PFJ). The type 2 diabetes model was induced by streptozotocin (STZ) administration, and PFJs were administered by adding them to the drinking water throughout the experiment. At the end of the experiment, DNA was isolated from intestinal samples, and the V3–V4 regions of the 16S rRNA gene were analyzed using next-generation sequencing (NGS). Alpha and beta diversity analyses showed that PFJ treatments exerted a balancing effect on the gut microbiota. Microbial diversity was highest in the Control group, whereas a significant decrease was observed in the Positive Control group. PFJ treatments particularly increased diversity in the Corn PFJ and Meadow Grass PFJ groups. Taxonomic analyses revealed that the dominant phyla in the gut microbiota were Firmicutes and Bacteroidota, and PFJ treatments helped maintain this natural balance. Furthermore, metabolic parameter evaluations indicated that the Alfalfa PFJ group exhibited the highest insulin levels and a significant reduction in blood glucose compared to all other groups. Overall, these findings suggest that PFJ treatments alleviate diabetes-related microbial dysbiosis, support the structural diversity of the gut microbiota, and may be considered potential biotherapeutic agents.