Microwave-assisted Synthesis of Silver Nanoparticles Using Cannabis sativaand Aegle marmelos Leaves for Potential Antibacterial Activity

Introduction: Nanomaterial-based antimicrobial agents have gained global attention due to their potent antibacterial activity. Green synthesis using plant extracts offers an eco-friendly and cost-effective alternative to conventional methods. In this study, silver nanoparticles (Ag NPs) were synthesised using Cannabis sativa and Aegle marmelos leaf extracts, and their antimicrobial efficacy was evaluated. Methods: Ag NPs were synthesised using a domestic microwave (180 sec, 400 W) with plant extracts. The synthesised NPs were characterised by X-ray diffraction (XRD), UV-visible spectroscopy, scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). Antibacterial activity was tested against Gram-positive (S. aureus) and Gram-negative (E. coli, S. typhi, Pseudomonas) bacteria at different concentrations. Results: Characterisation confirmed spherical Ag NPs clustered in morphology. Ag NPs synthesised using Cannabis sativa showed maximum inhibition zones of ~14 ± 0.7 mm (Pseudomonas). Aegle marmelos-derived Ag NPs exhibited higher inhibition zones of ~24 ± 1.2 mm (Pseudomonas), surpassing those of the commercial antibiotic (ZID~12 ± 0.6 mm) after 24 h of incubation. Discussion: Green synthesis of Ag NPs using Cannabis sativa and Aegle marmelos extract proved effective and eco-friendly. Aegle marmelos-derived Ag NPs showed stronger antibacterial activity, likely due to richer phytochemicals. The NPs were particularly effective against Pseudomonas. These results highlight their potential as sustainable antimicrobial agents. Conclusion: Cannabis sativa and Aegle marmelos are effective plant sources for green synthesis of Ag NPs, which exhibit significant antibacterial activity for both Gram-positive and Gram-negative bacterial strains. In particular, they are most effective against Pseudomonas, highlighting their potential in targeting pathogenic microorganisms.