Boswellia sacra leaf extract mediated biosynthesis of ZnO nanoparticles: Characterization, photocatalytic and antibacterial activity

Abstract

The Boswellia sacra or Olibanum tree has unique herbal properties in the Burseraceae family and has already been considered a versatile material in traditional Arabic medicine. Zinc oxide nanoparticles (ZnO NPs) were synthesized using B. sacra aqueous leaf extract as a mediator in the present study. As a critical reducing and stabilizing agent for ZnO NPs, B. sacra aqueous extract with reducing polysaccharides and phytochemicals have been used. UV-visible spectroscopy has preliminarily confirmed the formation of ZnO NPs. FTIR, XRD, and SEM analyses were used to classify the photosynthesized nanoparticles. The functional group present in the nanoparticles was analyzed using FTIR. X-ray diffraction has been used to validate the particles’ crystalline existence. SEM technique determined the nanoparticles’ morphology and crystalline phase of the nanoparticles. The enhanced photocatalytic activity for methylene blue as model pollutant dye under solar irradiation was 84% in 100 minutes. The antibacterial activity of ZnO NPs was tested using the agar diffusion technique against Staphylococcus aureus, Bacillus subtilis (gram-positive), and Escherichia coli Pseudomonas aeruginosa (gram-negative) species. ZnO NPs synthesized using B. sacra leaf extract exhibited promising results against Gram-positive and Gram-negative bacterial strains with a maximum inhibition zone of 15 mm and 14 mm, respectively. In conclusion, the results indicated that the protocol is quick, fast, one-step, eco-friendly, non-toxic, and alternative to physical/chemical traditional methods.