Gut microbiota in the Alzheimer’s disease (AD) patients and the control subjects. The relative abundance of the bacterial taxa in the feces from the control subjects and the AD patients classified in the stages GDS-3, GDS-4 and GDS-5. The data are the means ± the SEM; (n = 10, control subjects; n = 12, AD patients; 4 per stage). (A) The bacterial class, family and genera belonging to the phylum Bacteroidota. (B) The bacterial class, family and genera belonging to the phylum Actinobacteria. (C) The family Akkermansiaceae, genus Akkermansia and species Akkermansia muciniphila. The ANOVA shows an effect (p < 0.05) between the bacterial taxa and the AD patients classified in the stages. Tukey’s test: * p < 0.05and ** p < 0.01. c, class; f, family; g, genus, s, species.