Eco-friendly Biosynthesis of Silver Oxide Nanoparticles Using Boswellia carterii with Antibacterial Applications

<ns3:p>Abstract* Background Frankincense (Boswellia carterii) a natural resin rich in biologically active compounds, especially boswellic acids, which contribute to its anti-inflammatory and therapeutic properties. Plant extracts have become valuable in the green synthesis of metal nanoparticles because they act as safe, low-cost and stabilizing agents, offering an environmentally friendly alternative to conventional chemical methods. Methods In this study, silver oxide nanoparticles were prepared using an aqueous extract of Frankincense. The extract was obtained by dissolving 1 g of crude resin in 100 mL of deionized water, heating at 50°C, and filtering to remove insoluble material. A 1 mM solution of silver nitrate was prepared by dissolving 0.015 g of AgNO₃ in 100 mL of water. The silver solution was added gradually to the warm extract under continuous stirring, and the mixture was heated up to 140°C for 50 minutes until a dark brown color appeared, indicating nanoparticle formation. The product was then centrifuged, washed several times, and left to dry. Structural characterization was carried out using X-ray diffraction, and the crystallite size was calculated using the Scherrer equation. Particle morphology was examined by scanning electron microscopy. Results The antibacterial activity of the synthesized nanoparticles was evaluated against Pseudomonas aeruginosa and Streptococcus species at concentrations of 60%, 80%, and 100%. The XRD results confirmed the formation of silver oxide with an orthorhombic crystalline structure corresponding to standard reference data, with an average crystallite size of 80.6 nm. SEM images revealed that the particles were relatively uniform in distribution, with diameters ranging from 55.84 to 82.17 nm. Antibacterial testing showed clear inhibition zones measuring between 14.5 and 23 mm for both bacterial strains, with a stronger effect observed against Streptococcus. Conclusion These findings demonstrate that Boswellia carterii extract can serve as an effective natural agent for the green synthesis of silver oxide nanoparticles, producing particles with suitable structural characteristics and notable antibacterial activity.</ns3:p>