Bioengineered selenium nanoparticles synthesized using Ficus hispida ethyl acetate extract exhibit antibacterial and...

The emergence of multidrug-resistant bacteria necessitates the development of novel antimicrobial agents. Selenium nanoparticles (Se-NPs) synthesized via green methods offer promising antioxidant and antibacterial properties.

This study investigates the synthesis, characterization, and bioactivity of Se-NPs mediated by Ficus hispida extract.

Ficus hispida fruit extract was used to synthesize Se-NPs by mixing 10 mL of the extract with 20 mL of 50 mM selenium solution, followed by reduction with 200 μL of 40 mM ascorbic acid. The formation of Se-NPs was confirmed by a ruby red color. Characterization was performed using UV-Vis spectroscopy (peaks at 203 nm and 257 nm), FT-IR (bands at 3362, 3245, 1648, 1383, 1202 cm^-1), XRD (2θ: 23.5°, 29.7°, 41.4°, 43.6°, 45.4°, 51.7°, 55.9°, 61.5°), FE-SEM (particle size: 71.73-98.81 nm), HR-TEM (7.59-12.26 nm), zeta potential analysis (-37.1 mV), and EDAX (Se and O peaks). Antioxidant activity was assessed via DPPH assay, and antibacterial activity was evaluated by agar well diffusion against Escherichia coli, Bacillus subtilis, and Staphylococcus aureus.

Se-NPs showed strong surface plasmon resonance and high crystallinity with hexagonal structure. They were predominantly spherical, monodispersed, and exhibited excellent colloidal stability. Antioxidant activity reached 71 % inhibition at 100 μg/mL, while ascorbic acid achieved 98.22 %. Antibacterial tests revealed inhibition zones of 14 mm (E. coli, B. subtilis) and 18 mm (S. aureus), compared to ciprofloxacin's 31-32 mm. HR-TEM of S. aureus treated with Se-NPs showed significant morphological alterations.

Ficus hispida-mediated Se-NPs are eco-friendly, well-characterised, and display notable antioxidant and antibacterial activities, especially against Gram-positive bacteria. These findings support further biomedical exploration of FH-Se-NPs as alternative therapeutic agents.