Department of Physics, Kalasalingam Institute of Technology, Krishnan Koil 626 126, India.
Department of Physics, Park College of Technology, Karumathampatti, Coimbatore, 641 659, Tamil Nadu, India.
J Photochem Photobiol B. 2018 Apr;181:53-58. doi: 10.1016/j.jphotobiol.2018.02.011. Epub 2018 Feb 8.
The present work reports the green synthesis of Zinc Oxide Nanoparticles (ZnO NPs) using aqueous Tabernaemontana divaricata green leaf extract. ZnO NPs have been characterized by X-ray diffraction (XRD), Ultra Violet-Visible (UV-Vis) studies, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and Fourier Transform-Infra Red (FT-IR) analysis. XRD pattern analysis confirms the presence of pure hexagonal wurtzite crystalline structure of ZnO. The TEM images reveal the formation of spherical shape ZnO NPs with the sizes ranging from 20 to 50 nm. The FT-IR analysis suggests that the obtained ZnO NPs have been stabilized through the interactions of steroids, terpenoids, flavonoids, phenyl propanoids, phenolic acids and enzymes present in the leaf extract. Mechanism for the formation of ZnO NPs using Tabernaemontana divaricata as bioactive compound is proposed. As prepared ZnO NPs reveals antibacterial activity against three bacterial strains, Salmonella paratyphi, Escherichia coli and Staphylococcus aureus. The ZnO NPs shows higher antibacterial activity against S. aureus and E. coli and lesser antibacterial activity against S. paratyphi compared to the standard pharmaceutical formulation. Photocatalytic activity of synthesized ZnO NPs was analyzed for methylene blue (MB) dye degradation with sunlight. Almost complete degradation of dye occurred in 90 min. This nano-ZnO, prepared by eco-friendly method will be much useful for dye removal and bacterial decontamination.
本工作报道了使用水溶液中的 Tabernaemontana divaricata 绿叶提取物来绿色合成氧化锌纳米粒子（ZnO NPs）。通过 X 射线衍射（XRD）、紫外可见（UV-Vis）研究、扫描电子显微镜（SEM）、透射电子显微镜（TEM）和傅里叶变换红外（FT-IR）分析对 ZnO NPs 进行了表征。XRD 图谱分析证实了 ZnO 的纯六方纤锌矿晶体结构的存在。TEM 图像显示形成了尺寸范围为 20 至 50nm 的球形 ZnO NPs。FT-IR 分析表明，所获得的 ZnO NPs 通过叶提取物中存在的甾体、萜类、类黄酮、苯丙素、酚酸和酶的相互作用得到稳定。提出了使用 Tabernaemontana divaricata 作为生物活性化合物形成 ZnO NPs 的机制。所制备的 ZnO NPs 对三种细菌菌株（副伤寒沙门氏菌、大肠杆菌和金黄色葡萄球菌）表现出抗菌活性。与标准药物制剂相比，ZnO NPs 对金黄色葡萄球菌和大肠杆菌的抗菌活性更高，对副伤寒沙门氏菌的抗菌活性较低。用太阳光分析了合成的 ZnO NPs 对亚甲基蓝（MB）染料降解的光催化活性。在 90 分钟内几乎完全降解了染料。这种通过环保方法制备的纳米 ZnO 将非常有助于去除染料和细菌污染。
