School of Biosciences, Mahatma Gandhi University, Kottayam, Kerala, India.
School of Biosciences, Mahatma Gandhi University, Kottayam, Kerala, India.
Microb Pathog. 2020 Jan;138:103832. doi: 10.1016/j.micpath.2019.103832. Epub 2019 Nov 2.
The mycofabrication of silver nanoparticles (AgNPs) through green chemistry protocol is an advanced methodological progress in medical nanotechnology. Mycofabricated AgNPs are less toxic due to an aura of biomolecules around the nanoparticles. Hence the mycofabricated AgNPs can be used for clinical applications. The present study explores the antibiofilm activity of mycogenerated AgNPs, which were synthesized by the enzymatic reduction of silver nitrate using the marine algicolous endophytic fungus Penicillium polonicum ARA10. The mycogenerated AgNPs showed very specific and potent bactericidal activity against Acinetobacter baumannii. Anti-A.baumannii activities of mycogenerated AgNPs on planktonic as well as biofilm embedded cells were explored. The physical impact of synthesized AgNPs on A.baumannii was investigated by scanning electron microscopy and fluorescence microscopy. A bionanocomposite coating for the central venous catheter (CVC) was formulated using the mycogenerated AgNPs and polydopamine. The bionanocomposite surface was characterized by field emission scanning electron microscopy, water contact angle measurement, and Raman spectroscopy. The results showed that the mycogenerated AgNPs have potent antibiofilm activity on biofilms of A.baumannii. The scanning electron microscopy (SEM) and fluorescence microscopy images showed noticeable aberrations on the ultrastructure of A.baumannii. The SEM and FE-SEM images of biofilms on the surface of CVC samples proved that the AgNPs at minimum bactericidal concentration could destroy the structure of biofilms and lyses the bacterial cell. Thus, the present study establishes a new way to the development of 'antibacterial surfaces' based on mycogenerated AgNPs.
通过绿色化学方法制造银纳米粒子（AgNPs）是医学纳米技术的一个先进方法学进展。由于纳米粒子周围存在生物分子的氛围，因此真菌制造的 AgNPs 的毒性较低。因此，真菌制造的 AgNPs 可用于临床应用。本研究探讨了通过海洋藻类内生真菌 Penicillium polonicum ARA10 酶促还原硝酸银合成的真菌生成 AgNPs 的抗生物膜活性。真菌生成的 AgNPs 对鲍曼不动杆菌表现出非常特异和有效的杀菌活性。研究了真菌生成的 AgNPs 对浮游生物和生物膜嵌入细胞的抗 A.baumannii 活性。通过扫描电子显微镜和荧光显微镜研究了合成 AgNPs 对 A.baumannii 的物理影响。使用真菌生成的 AgNPs 和聚多巴胺配制了用于中央静脉导管（CVC）的生物纳米复合材料涂层。通过场发射扫描电子显微镜、水接触角测量和拉曼光谱对生物纳米复合材料表面进行了表征。结果表明，真菌生成的 AgNPs 对鲍曼不动杆菌生物膜具有很强的抗生物膜活性。扫描电子显微镜（SEM）和荧光显微镜图像显示 A.baumannii 超微结构出现明显异常。CVC 样品表面生物膜的 SEM 和 FE-SEM 图像证明，最低杀菌浓度的 AgNPs 可以破坏生物膜的结构并溶解细菌细胞。因此，本研究为基于真菌生成的 AgNPs 开发“抗菌表面”开辟了新途径。
