Novel microbial route to synthesize ZnO nanoparticles using Aeromonas hydrophila and their activity against pathogenic bacteria and fungi

• Published in: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy Molecular and biomolecular spectroscopy, 2012-05, Vol.90, p.78-84
• Main Authors: Jayaseelan, C., Rahuman, A. Abdul, Kirthi, A. Vishnu, Marimuthu, S., Santhoshkumar, T., Bagavan, A., Gaurav, K., Karthik, L., Rao, K.V. Bhaskara
• Format: Article
• Language: English
• Subjects: Aeromonas hydrophila; Antimicrobial activity; Atomic force microscopy; Electron microscopy; ZnO nanoparticles
• ISSN: 1386-1425
• DOI: 10.1016/j.saa.2012.01.006

Bacteria-mediated biosynthesis of zinc oxide nanoparticles (ZnO NPs) using Aeromonas hydrophila as eco-friendly reducing and capping agent. The synthesized ZnO NPs were characterized by UV–vis spectroscopy, XRD, FTIR, AFM, non-contact mode AFM and FESEM with EDX analyses. The AFM identifies the topological appearance and the size range was found to be 57.72nm providing a 3D profile of the surface on a nanoscale. The surface area of the nanoparticles has increased dramatically showing with the increase in the peaks. The FESEM study showed that biodegradable nanoparticles were smooth and spherical in shape. The ZnO NPs showed the maximum zone of inhibition against Pseudomonas aeruginosa (22mm) and Aspergillus flavus (19mm). [Display omitted] ► Biosynthesis mode for green low cost tactic, capable of creating ZnO NPs at 37°C. ► Bacteria, Aeromonas hydrophila mediated synthesis of ZnO NPs is reported. ► The UV peak was practical at 374nm which is typical to monodispersed nanoparticles. ► The characterization was made by XRD, AFM, NC-AFM and SEM–EDX analysis. ► The ZnO NPs was spherical, irregular with sharp edges and the size of 57.72nm. In the present work, we describe a low-cost, unreported and simple procedure for biosynthesis of zinc oxide nanoparticles (ZnO NPs) using reproducible bacteria, Aeromonas hydrophila as eco-friendly reducing and capping agent. UV–vis spectroscopy, XRD, FTIR, AFM, NC-AFM and FESEM with EDX analyses were performed to ascertain the formation and characterization of ZnO NPs. The synthesized ZnO NPs were characterized by a peak at 374nm in the UV–vis spectrum. XRD confirmed the crystalline nature of the nanoparticles and AFM showed the morphology of the nanoparticle to be spherical, oval with an average size of 57.72nm. Synthesized ZnO NPs showed the XRD peaks at 31.75°, 34.37°, 47.60°, 56.52°, 66.02° and 75.16° were identified as (100), (002), (101), (102), (110), (112) and (202) reflections, respectively. Rietveld analysis to the X-ray data indicated that ZnO NPs have hexagonal unit cell at crystalline level. The size and topological structure of the ZnO NPs was measured by NC-AFM. The morphological characterization of synthesized nanoparticles was analyzed by FESEM and chemical composition by EDX. The antibacterial and antifungal activity was ended with corresponding well diffusion and minimum inhibitory concentration. The maximum zone of inhibition was observed in the ZnO NPs (25μg/mL) against Pseudomonas aeruginosa (22±1.8mm) an