Nanobiotechnology and Molecular Biology Research Lab, Department of Food Science and Nutrition, College of Food and Agriculture Sciences, King Saud University, Riyadh 11541, Saudi Arabia.
Nanobiotechnology and Molecular Biology Research Lab, Department of Food Science and Nutrition, College of Food and Agriculture Sciences, King Saud University, Riyadh 11541, Saudi Arabia.
Microb Pathog. 2018 Jul;120:85-96. doi: 10.1016/j.micpath.2018.04.035. Epub 2018 Apr 21.
The appearance of drug-resistant (DR) bacteria in the community is a crucial development, and is associated with increased morbidity, mortality, healthcare costs, and antibiotic use. Natural oil nanoemulsions (NEs) have potential for antimicrobial applications. In the present study, we determined the antimicrobial activity of an NE against DR bacterial pathogens in vitro. The NE comprised Cleome viscosa essential oil, Tween 80 nonionic surfactant, and water. We found that an NE with a droplet size of 7 nm and an oil:surfactant (v/v) ratio of 1:3 was effective against methicillin-resistant Staphylococcus aureus (MRSA), DR Streptococcus pyogenes, and DR extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa. Fourier-transform infrared (FTIR) spectroscopy revealed that NE treatment modified the functional groups of lipids, proteins, and nucleic acids in DR bacterial cells. Scanning electron microscopy (SEM) showed damage to the cell membranes and walls of NE-treated DR bacteria. These alterations were caused by bioactive compounds with wide-spectrum enzyme-inhibiting activity in the NE, such as β-sitosterol, demecolcine, campesterol, and heneicosyl formate. The results suggest that the nanoemulsion is effective against DR bacteria, and acts by inhibiting the drug efflux mechanism of DR strains.
耐药（DR）细菌在社区中的出现是一个关键的发展，与发病率、死亡率、医疗保健成本和抗生素使用增加有关。天然油纳米乳液（NE）具有抗菌应用的潜力。在本研究中，我们确定了一种 NE 对体外 DR 细菌病原体的抗菌活性。该 NE 由醉蝶花精油、吐温 80 非离子表面活性剂和水组成。我们发现，油滴大小为 7nm、油：表面活性剂（v/v）比为 1:3 的 NE 对耐甲氧西林金黄色葡萄球菌（MRSA）、DR 化脓性链球菌和 DR 产超广谱β-内酰胺酶（ESBL）的大肠杆菌、肺炎克雷伯菌和铜绿假单胞菌有效。傅里叶变换红外（FTIR）光谱显示，NE 处理改变了 DR 细菌细胞中脂质、蛋白质和核酸的功能基团。扫描电子显微镜（SEM）显示，NE 处理后的 DR 细菌的细胞膜和细胞壁受损。这些变化是由 NE 中具有广谱酶抑制活性的生物活性化合物引起的，如β-谷甾醇、秋水仙素、菜油甾醇和二十一烷酸甲酯。结果表明，纳米乳液对 DR 细菌有效，通过抑制 DR 菌株的药物外排机制发挥作用。
