Antibacterial activity of thymol/carvacrol and clinoptilolite composites prepared by supercritical solvent impregnation
Antibacterial activity of thymol/carvacrol and clinoptilolite composites prepared by supercritical solvent impregnation
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DOI：
10.1007/s10934-021-01107-y
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发表时间：
2021-06-16
影响因子：
2.6
通讯作者：
Rajic, Nevenka
中科院分区：
文献类型：
--
作者：
Dikic, Jelena;Lukic, Ivana;Rajic, Nevenka
以天然沸石-斜沸石和单萜酚-百里香酚和香薰醇为原料，在超临界二氧化碳（scCO(2)）中，在30 MPa和35℃条件下，经18 h超临界溶剂浸染（SSI）制备了新型复合材料。复合材料中酚类物质（百里香酚-23.0 wt%和香薰酚-19.1 wt%）的含量通过C、h、N和热分析（TGA）测定；傅里叶变换红外光谱（FTIR）和粉末x射线衍射（PXRD）研究了酚类化合物与沸石晶格的相互作用，表明复合材料中保留了沸石晶格。复合材料在不同的水介质（磷酸盐缓冲液、泉水和湖水）中对革兰氏阴性菌大肠杆菌DSM 498和革兰氏阳性菌金黄色葡萄球菌ATCC 25923均有抑菌活性。经1 h后，含香芹酚的斜沸石抗菌活性优于含百里香酚的复配物。两种复合材料在接触24 h后均表现出杀菌效果。百里香酚（22.7-32.1%）比香芹酚（6.2-8.9%）在水中的浸出更明显，表明空间位阻效应对解吸过程的影响。
Novel composites based on natural zeolite-clinoptilolite and monoterpene phenols-thymol and carvacrol were prepared by supercritical solvent impregnation (SSI) in supercritical carbon dioxide (scCO(2)) at 30 MPa and 35 degrees C during 18 h. The content of phenols in composites (thymol-23.0 and carvacrol-19.1 wt%) was determined using both C,H,N and thermal analysis (TGA); interactions of the phenols with the zeolite lattice studied by Fourier transform infrared spectroscopy (FTIR) and powder X-ray diffraction (PXRD) showed that the zeolite lattice was preserved in the composites. The composites exhibited antibacterial activity toward Gram-negative bacteria Escherichia coli DSM 498 and Gram-positive bacteria Staphylococcus aureus ATCC 25923 in different water media (phosphate buffer solution, spring water and lake water). After 1 h carvacrol-containing clinoptilolite showed better antibacterial activity than composite with thymol. Both composites expressed bactericidal effect after 24 h of contact. Leaching of the phenols from composite in water was more pronounced from thymol (22.7-32.1%) than for carvacrol (6.2-8.9%) suggesting influence of steric effect on the desorption process.