Fig. 2

MK-7 intervention promotes differential alterations of gut microbiota and fecal metabolites. A–D Alterations of gut microbiota over 6-month MK-7 intervention. A Overview of the observed amount of OTUs. B Alpha diversity measured by the observed index and Simpson index and *P < 0.05, ** P < 0.01, ***P < 0.001 by one-way ANOVA. C PCoA based on weighted Unifrac distance showed different taxonomic compositions between NC and VK groups at a terminal time point, and no significance was shown at baseline (lower left corner). P value was measured by AMOVA. D Heatmap showing the significantly differential microbial genus (P < 0.05 or LDA > 3) after 6-month MK-7 intervention accompanied with their corresponding baseline status. The colors changing from blue to red indicate higher relative abundance. E Coabundance network at terminal time point. The edges represent significant Pearson correlations of > 0.6 or < -0.6 between genera. Each node represents a genus and is colored based on the affiliated phylum. After 6-month MK-7 intervention accompanied by their corresponding baseline status. Node is based on the degree of connectivity. Blue dashed and orange edges indicate positive correlations in the NC group and VK group and gray edges indicate negative correlations. F Dumbbell chart showing the significantly differential fecal metabolites (P < 0.05 or VIP > 1) after 6-month MK-7 intervention accompanied with their corresponding baseline status