MEL-A-ZnONPs的制备、表征及抗菌活性研究

Preparation, characterization, and antibacterial activity of MEL-A-ZnONPs

为提高纳米氧化锌(zinc oxide nanoparticles,ZnONPs)的分散性和抗菌活性,该研究将绿色、无毒的A型甘露糖赤藓糖醇脂(mannosylerythritol lipids-A,MEL-A)用于ZnONPs的制备和修饰,并利用紫外可见光谱、X射线衍射、傅里叶红外光谱、纳米粒度、Zeta电位和透射电镜-能谱等方法进行表征。结果表明,MEL-A添加浓度为0.250 mmol/L时,制备出的0.250MEL-A-ZnONPs平均粒径及多分散系数(polydispersity index,PDI)值最小,分别为(78.25±27.26)nm和0.155,Zeta电位的绝对值达到最大,为-22.89 mV,且透射电镜形貌及分散性最好,显著优于未修饰的对照组(N-ZnONPs)。利用最小抑菌浓度(minimum inhibitory concentration,MIC)、最小杀菌浓度(minimum bactericidal concentration,MBC)、生长曲线、抑菌圈等实验评价ZnONPs的抗菌性能,发现N-ZnONPs和0.250MEL-A-ZnONPs对金黄色葡萄球菌的MIC均为12.0 mg/L,MBC分别为24.0 mg/L和16.0 mg/L,对大肠杆菌的MIC分别为24.0 mg/L和20.0 mg/L,MBC分别为32.0 mg/L和24.0 mg/L,表明MEL-A-ZnONPs对金黄色葡萄球菌具有更好的抗菌效果。

The green and non-toxic mannosylerythritol lipids-A(MEL-A)was used to improve the dispersibility and antibacterial activity of zinc oxide nanoparticles(ZnONPs).The characterization of the modified ZnONPs was conducted using UV-vis spectroscopy,X-ray diffraction,Fourier transform infrared spectroscopy,nano-particle size,Zeta potential,and transmission electron microscopy-energy spectroscopy.Results showed that the average particle size and PDI value of 0.250MEL-A-ZnONPs were the lowest,with a Zeta potential of-22.89 mV.The transmission electron microscope morphology and dispersibility of the modified ZnONPs were significantly better than the unmodified N-ZnONPs.The antibacterial property of ZnONPs was evaluated using minimum inhibitory concentration(MIC),minimum bactericidal concentration(MBC),growth curve,and inhibition zone tests.The MIC of N-ZnONPs and 0.250MEL-A-ZnONPs against Staphylococcus aureus were both 12.0 mg/L,while the MBC were 24.0 mg/L and 16.0 mg/L,respectively.The MIC of MEL-A-ZnONPs against Escherichia coli were 24.0 mg/L and 20.0 mg/L,and the MBC were 32.0 mg/L and 24.0 mg/L,respectively.These results demonstrate that MEL-A-ZnONPs is more effective against S.aureus than the unmodified N-ZnONPs.