Fig. 3

Multivariate statistical analysis of differential metabolites. a Donut plot of metabolite classification and proportions. Different color blocks represent different taxonomic categories, and percentages represent the percentage of metabolites belonging to that type in the total number of metabolites identified. b Heatmap of differentially abundant metabolites between the control and CE groups. The horizontal axis represents the names of the serum samples from the CE group and healthy control group, and the vertical axis represents the different metabolites. Red indicates that the substance is highly expressed in the group where it is located, blue indicates that the substance is low in the group where it is located, and the depth indicates the degree of influence. c Volcano map of differentially abundant metabolite screening results. Significantly upregulated metabolites are shown in red, significantly downregulated metabolites are shown in blue, and non-significantly differentiated metabolites are shown in gray