The biomedical potential of silver nanoparticles (AgNPs) synthesised from Guilandina bonduc seeds was evaluated in this study. A colour change supported the visual confirmation of AgNPs synthesis, and the UV–Visible spectroscopy showed the characteristic surface plasmon resonance peak at 438 nm. Phytochemical groups, including phenolics, carbonyls, and amines, were identified through FT-IR analysis, acting both as reducing agents and stabilisers for nanoparticle formation. X-ray diffraction confirmed the crystalline nature of the nanoparticles, while SEM analysis revealed cubic in shape particles in the size. Dynamic light scattering analysis provided an average particle size of 98.4 nm, with a polydispersity index of 0.514. Zeta potential values for − 11.7 mV. The G. bonduc seed-derived AgNPs exhibited significant antimicrobial activity, with the highest efficacy against Staphylococcus haemolyticus (16.26 mm), followed by Aeromonas hydrophila (14.53 mm) and Escherichia coli (11.63 mm). The antioxidant activity of the synthesised AgNPs was confirmed through DPPH, hydroxyl radical (HRSA), and hydrogen peroxide (H₂O₂) scavenging assays. In the DPPH assay, the AgNPs exhibited an IC₅₀ value of 73.31 μg/mL, indicating strong free radical scavenging potential. Similarly, the HRSA assay showed an IC₅₀ value of 95.92 μg/mL, demonstrating effective hydroxyl radical neutralisation. The H₂O₂ scavenging assay showed an IC₅₀ value of 107.61 μg/mL, further confirming their notable antioxidant potential of G. bonduc seed-derived AgNPs. Additionally, G. bonduc seed-derived AgNPs demonstrated significant cytotoxic effects against PA-1 ovarian cancer cells, with an IC₅₀ value of 56.36 μg/mL. Apoptosis was confirmed by AO/EtBr staining and morphological changes. These findings not only highlight the antimicrobial, antioxidant, and anticancer activities of AgNPs but also emphasise their potential for sustainable therapeutic applications in biomedical fields.
Ayyadurai et al. (Sun,) studied this question.