D-青霉胺稳定银簇聚集体对大肠杆菌和金黄色葡萄球菌抑制作用

Inhibitory effect of D-penicillamine stabilized silver cluster on Escherichia coli and Staphylococcus aureus

目的探讨D-青霉胺稳定的银簇聚集体对大肠杆菌和金黄色葡萄球菌的抑制作用。方法利用红外光谱、X-射线光电子能谱和俄歇电子谱分析银簇聚集体的结构;并将银簇聚集体与细菌混合培养,探讨银簇聚集体的抑菌作用。利用扫描电子显微镜观察细菌培养后状态。结果银簇聚集体对大肠杆菌最低抑菌浓度(MIC)为1μg/mL,半抑制浓度IC;为0.86μg/mL;银簇聚集体对金黄色葡萄球菌无抑制作用,即使银簇聚集体浓度达到大肠杆菌MIC的200倍也无抑菌效果。扫描电子显微镜结果表明,与银簇聚集体培养后,大肠杆菌的细胞膜发生明显破裂,导致细菌死亡。结论银簇聚集体对大肠杆菌具有明显抑制作用,对金黄色葡萄球菌无抑制作用。

Objective To observe inhibitory effect of silver cluster assemblies capped by D-penicillamine on Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus).Methods The structure of D-penicillamine stabilized silver cluster assemblies was examined with infrared spectroscopy,X-ray photoelectron spectroscopy and Auger electron spectroscopy.Then,the E.coli and S.aureus strains were cultivated with various doses of D-penicillamine stabilized silver cluster assemblies.Scanning electron microscope was used to observe the proliferation of the cultivated bacteria.Results The minimum inhibitory concentration(MIC)and the half maximal inhibitory concentration of silver cluster assemblies for E.coli were 1μg/mL and 0.86μg/mL;no inhibition effect of silver cluster assemblies on S.aureus at the concentration of 200 times higher than the MIC for E.coli.Observations with scanning electron microscope revealed obvious rupture of the cell membranes of E.coli cultivated with silver cluster assemblies,which may be contributed to the bacterial death.Conclusion Silver cluster assemblies has obvious inhibition effect on E.coli but no such effect on S.aureus.