摘要
为制备载铜蒙脱石(Cu-MMT)并研究其杀菌活性及机制,采用离子交换法制得Cu-MMT,对其结构与表面特性进行表征。以大肠杆菌为试验菌株,检测Cu-MMT对细菌的最小抑菌浓度(MIC)和最小杀菌浓度(MBC),Cu-MMT杀菌过程中菌液胞内酶活性的变化,并观察细菌形态。结果显示,载铜后蒙脱石的离子交换容量增大,但比表面积和表面负电荷密度下降;Cu-MMT对大肠杆菌的MIC和MBC分别为0.16和0.64mg.mL-1;Cu-MMT可使细菌细胞膜受损,胞内酶诸如冬氨酸氨基转移酶、乳酸脱氢酶和丙氨酸氨基转移酶等外泄。Cu-MMT对细菌具有较强的杀灭活性,其杀菌机制:Cu-MMT与细菌发生吸附作用,使细菌细胞膜形态和通透性改变,胞内物外泄而死亡。
The aims of this study were to prepare Cu^2＋-loaded montmorillonite （Cu-MMT） and investigate its bactericidal activity and mechanism. Cu-MMT was prepared by the method of ion exchange reaction. The structure and surface characteristic of Cu-MMT were determined. Minimum inhibitory concentration （MIC） and minimum bactericidal concentration （MBC） of Cu-MMT against the strain of Escherichia coli were determined. The activities of intracellular enzyme in bacterial solution were measured, and the morphology of E. coli was observed during the interaction between Cu-MMT and bacteria. The results showed that treatment with Cu^2 ＋ increased cation exchange capacity of montmorillonite, but specific surface area and surface negative charge density were decreased. The MIC and MBC of Cu-MMT against the tested E. coli were 0. 16 and 0. 64 mg · mL^-1 , respectively. Cu-MMT could destroy bacterial cellular membrane and then resulted in leakage of intracellular enzymes such as asparate aminotransferase, lactate dehydrogenase and alanine aminotransferase. These suggest that Cu- MMT has a strong bactericidal activity. The bactericidal mechanism of Cu-MMT may be that bacteria are adsorbed by Cu-MMT, and then morphology and permeability of cellular membrane are changed. This leads to an effiux of intracellular contents and the death of bacteria.
出处
《药学学报》
CAS
CSCD
北大核心
2007年第3期318-322,共5页
Acta Pharmaceutica Sinica
基金
宁夏自然科学基金资助项目(NZ0609)
宁夏高等学校科学研究项目资助
关键词
蒙脱石
铜离子
大肠杆菌
抗菌活性
杀菌机制
montmorillonite
copper ion
Escherichia coli
antibacterial activity
bactericidal mechanism
