Thaya Rajagopalan, Malaikozhundan Balasubramanian, Vijayakumar Sekar, Sivakamavalli Jeyachandran, Jeyasekar Raja, Shanthi Sathappan, Vaseeharan Baskaralingam, Ramasamy Palaniappan, Sonawane Avinash
Crustacean Molecular Biology and Genomics Division, Biomaterials and Biotechnology in Animal Health Lab, Department of Animal Health and Management, Alagappa University, Karaikudi, 630 003, Tamil Nadu, India.
Department of Zoology, S.T. Hindu College, Nagercoil, 629 002, Tamil Nadu, India.
Microb Pathog. 2016 Nov;100:124-132. doi: 10.1016/j.micpath.2016.09.010. Epub 2016 Sep 10.
In the present study, chitosan coated Ag/ZnO (CS/Ag/ZnO) nanocomposite was synthesized and characterized by UV-Vis spectroscopy (UV-Vis), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and Scanning electron microscopy (SEM). The CS/Ag/ZnO nanocomposite exhibited antibacterial activity against Gram positive (B. licheniformis and B. cereus) bacteria at 8 μg mL compared to Gram negative (V. parahaemolyticus. and P. vulgaris) bacteria. CS/Ag/ZnO nanocomposite effectively inhibited the biofilm growth of Gram positive bacteria compared to Gram negative bacteria at 30 μg mL. The hydrophobicity index and EPS (extracellular polysaccharide) production of both Gram positive and Gram negative bacteria was decreased after treatment with 30 μg mL of CS/Ag/ZnO nanocomposite. CS/Ag/ZnO nanocomposite showed effective control of fungal C. albicans biofilm (92%) at 50 μg mL. The inhibition of bacterial and fungal biofilms was clearly visualized under light and confocal laser scanning microscopy (CLSM). CS/Ag/ZnO nanocomposite was observed to be non toxic to RAW264.7 murine macrophages and no changes in the morphology of macrophages was observed under phase contrast microscopy. The study concludes that CS/Ag/ZnO nanocomposite is the promising candidate to be used as biomaterial against bacterial and fungal infections without any toxicity risk.
在本研究中，合成了壳聚糖包覆的Ag/ZnO（CS/Ag/ZnO）纳米复合材料，并通过紫外-可见光谱（UV-Vis）、X射线衍射（XRD）、傅里叶变换红外光谱（FTIR）和扫描电子显微镜（SEM）对其进行了表征。与革兰氏阴性菌（副溶血性弧菌和普通变形杆菌）相比，CS/Ag/ZnO纳米复合材料在8μg/mL时对革兰氏阳性菌（地衣芽孢杆菌和蜡样芽孢杆菌）表现出抗菌活性。在30μg/mL时，与革兰氏阴性菌相比，CS/Ag/ZnO纳米复合材料能有效抑制革兰氏阳性菌的生物膜生长。用30μg/mL的CS/Ag/ZnO纳米复合材料处理后，革兰氏阳性菌和革兰氏阴性菌的疏水性指数和胞外多糖（EPS）产量均降低。CS/Ag/ZnO纳米复合材料在50μg/mL时对白色念珠菌生物膜显示出有效控制（92%）。在光学显微镜和共聚焦激光扫描显微镜（CLSM）下可清楚地看到细菌和真菌生物膜的抑制情况。观察到CS/Ag/ZnO纳米复合材料对RAW264.7小鼠巨噬细胞无毒，在相差显微镜下未观察到巨噬细胞形态的变化。该研究得出结论，CS/Ag/ZnO纳米复合材料是一种有前途的生物材料候选物，可用于对抗细菌和真菌感染，且无任何毒性风险。
