Fig. 3

OI improves intestinal dysbiosis in aged mice after anesthesia and surgery. The intestinal contents of aged mice were subjected to 16S rRNA gene sequencing. a, b Differences in the intestinal flora composition of aged mice among the three groups of aged mice; a Relative abundance in the Phylum levels, Negativicutes and Bacteroidia increased after POCD and decreased after OI treatment, while Bacilli decreased after POCD and increased after OI treatment. b Relative abundance in the Genus levels, Lactobacillaceae and Erysipelotrichaceae decreased after POCD and increased after OI treatment, while Lachnospiraceae increased after POCD and decreased after OI treatment. c β-diversity by PCoA. d Chao1 index to characterize richness, Simpson and Shannon indices to characterize diversity, and OI treatment after POCD decreased richness and diversity (*p < 0.05 vs. POCD, one-way ANOVA). e, f Gut microbial markers identified by LEfSe analysis. g, h PICRUSt analysis determined the potential function of the gut microbiota in the administration of OI therapy after POCD. n = 5 for 16S rRNA gene sequencing