Antibacterial activity and characterization of zinc oxide nanoparticles synthesized by microalgae.

Biosynthesis of zinc oxide nanoparticles (ZnO-NPs) using microalgae is novel and cost-effective approach. We studied production, molecular characterization, and antibacterial activity. Filtrates of isolated microalgae strain ZAA1 (MF140241), ZAA2 (MF114592) and ZAA3 (MF114594) were used. Incubation of these strains in 5mM solution of zinc nitrate was resulted in the synthesis of ZnO-NPs. Fourier-transform infrared, UV-visible spectroscopy and scanning electron microscopy were used to characterize the nanoparticles. Significant antibacterial activity of ZnO-NPs was measured against Escherichia coli, Staphylococcus aureus, Micrococcus luteus, Klebsiella pneumoniae and Citrobacter freundii. The microalgae mediated ZnO-NPs production is a successful procedure that can be used in a wide range of biomedical applications.