基于网络药理学的紫斑牡丹花、叶抗菌活性和作用机制研究

Exploration on antibacterial activity and mechanism of flowers and leaves from Paeonia rockii based on network pharmacology

该研究考察紫斑牡丹花、叶的抗菌活性，筛选其抗菌主要活性成分，预测抗菌靶点，探讨其多成分、多靶点抗菌作用机制。首先，采用微量稀释法测定甲醇、乙酸乙酯提取紫斑牡丹花、叶对金黄色葡萄球菌、表皮葡萄球菌、枯草芽孢杆菌、蜡样芽胞杆菌、大肠杆菌、肺炎克雷伯氏菌、铜绿假单胞菌的最小抑菌浓度（MIC）。其次，利用Uniprot数据库找到相对应的基因靶点，并通过RCSB网站寻找相对应的蛋白亚型的PDBID以及小分子结构为受体，前期已鉴定的紫斑牡丹花、叶化学成分以PubChem等数据库进行结构确认，通过Chem Draw，Avogadro和Discovery Studio Visualizer软件进行配体的构建，采用QuickVina2．0软件进行分子对接。最后，借助Cytoscape3．5．1软件绘制活性成分与抗菌靶点网络图，使用Uniprot在线数据库进行靶点基因功能及代谢通路进行分析。实验结果表明紫斑牡丹花、叶提取物具有抗菌活性，紫斑牡丹花甲醇提取物具有最强的抗菌作用。网络分析表明紫斑牡丹花、叶中筛选得到活性成分29个，抗菌靶点18个。通过紫斑牡丹花、叶活性成分与抗菌靶点网络数的比较，预测其抗菌成分主要是黄酮和酚酸，抗菌机制主要是抑制细菌蛋白的合成。该研究通过体外抗菌实验和网络药理学的筛选，发现紫斑牡丹花、叶提取物具有抗菌活性，为紫斑牡丹花、叶抗菌机制研究提供新的思路和线索。

This paper aimed to investigate the antibacterial activity of flowers and leaves from Paeonia rockii, screen antibacterial compounds and predict targets of antibacterial to explore its multi-component, multi-target antibacterial mechanism. In this study, min- imal inhibitory concentration （MIC） of seven strains of Staphylococcus attreus , S. epidermidi, Bacillus subtilis , B. cereus, Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa were determined by microdilution method. Uniprot databases was used to find the antibacterial targets, and RCSB was used to identify targets associated with antimicrobial activity as docked receptor proteins. The candidate active ingredients from flowers and leaves of P. rockii were identified by database such as PubChem. The ligands were con- structed by ChemDraw, Avogadro and Discovery Studio Visualizer. QuickVina 2. 0 software was used to molecular docking. Besides, the Cytoscape 3.5.1 software was used to construct activity compounds of flowers and leaves from P. rockii ingredients-targets network,and Uniprot software was used to analyze gene ontology and KEGG pathway. In vitro antibacterial experiments found antibacterial effect of the flowers and leaves from- P. rockii, especially methanol extraction of flowers has the strongest antibacterial effect. The network pharmacology indicated that total 29 activity ingredients and their 18 targets were screened in flowers and leaves from P. rockii. Com- parison of the active ingredients and the number of antimicrobial target networks, it is predicted that the antibacterial components are mainly flavonoids and phenolic acids and main mechanism of antibacterial is to inhibit the synthesis of bacterial proteins. In this study, potential antibacterial activity of flowers and leaves from P. rockii has be found by antibacterial experiments in vitro and network phar- macology screening. And this study provides new clues for further basic study on the antibacterial agents of flowers and leaves from P. rockii.