Fig. 3

Bioinformatics analysis of differential metabolites. The univariate statistical analysis of the Volcano plot showed the metabolite changes between control and functional constipation in positive ion and negative ion mode (A). The upward trend in metabolites was indicated by red scatters, the downward trend in metabolites was indicated by blue scatters, and the non-significant trend in metabolites was indicated by black scatters. The correlation heat map was used to highlight the relationship between significantly altered metabolites in positive ion and negative ion mode (B). The histogram of the KEGG enrichment pathway were used to further explore the mechanism of action of gut microbiota and metabolites in children with constipation (C)