Abstract: 【Objective】 This study was aimed to explore the active ingredients and mechanism of action of Astragalus membranaceus (Fisch.) Bunge.on flora imbalance diarrhea in piglets based on network pharmacology and molecular docking.【Method】 The main chemical constituents and the potential targets of Astragalus membranaceus (Fisch.) Bunge.were obtained and collected by traditional Chinese medicine systematic pharmacology (TCMSP) database.Targets of flora imbalance diarrhea were derived from GeneCards and OMIM databases.The targets predicted by the two methods were mapped to obtain the common action targets. STRING database was used to construct the interaction relationship between target proteins,and Cytoscape_3.8.0 software was used to analyze the topology of the network.DAVID database was used to analyze the enrichment of co-acting targets.The core components and core targets were docked by AutoDuck_4.2.6 software.【Result】 There were 11 core components in Astragalus membranaceus (Fisch.) Bunge. which regulated flora imbalance diarrhea in piglets,corresponding to 65 target genes,854 disease targets and 25 intersection targets.Tumor necrosis factor(TNF),transcription factor AP-1(JUN),Caspase-3(CASP3),interleukin-6(IL6),NF-kappa-B inhibitor alpha (NFKBIA),IL1B,IL10,cellular tumor antigen p53(TP53),peroxisome proliferator-activated receptor gamma(PPARG) and C-C motif chemokine 2 (CCL2) were shown as key targets in PPI network.GO function and KEGG pathway enrichment analysis showed that the effective components of Astragalus membranaceus (Fisch.) Bunge.were involved in transcriptional regulation,immune response,cell response to lipopolysaccharide and other biological processes through American trypanosomiasis,inflammatory bowel disease,amoebiasis,cytokine-cytokine receptor interaction,influenza A,malaria,T cell receptor signal pathway and Salmonella infection.The results of molecular docking showed that the core components such as quercetin,kaempferol and formononetin were closely bound to the key targets such as TNF and IL1B,and had good affinity.【Conclusion】 The Astragalus membranaceus (Fisch.) Bunge.might have therapeutic effect on flora imbalance diarrhea in piglets by TNF,IL1B and other targets through main active ingredients such as quercetin,kaempferol and formononetin,and by participating in american trypanosomiasis,inflammatory bowel disease,malaria,T cell receptor signal pathway,Salmonella infection and other pathways.

Key words: Astragalus membranaceus(Fisch.) Bunge.; flora imbalance diarrhea; network pharmacology; molecular docking; active composition; action mechanism