Biological potential of <i>Argyrolobium roseum</i> (Camb.) Jaub &amp; Spach mediated silver nanoparticles and their effect on the growth of wheat seeds

The green synthesis of silver nanoparticles (AgNPs) using plant-based derivatives is getting attention for biological applications because of their small dimensions and shape. In this study, AgNPs were prepared using leaf extract of Argyrolobium roseum (A. roseum) (Camb.) Jaub. & Spach. and then characterized via Fourier transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), scanning electron microscopy (SEM) and ultraviolet-visible absorption (UV-Vis) spectroscopy. The UV-visible spectrum displayed a absorption peak at 450 nm and x-ray diffraction depicted a crystalline nature of biogenic NPs. FTIR analysis showed various functional groups involved in the reduction and capping of AgNPs while SEM revealed the spherical form of synthesized AgNPs. The antibacterial assay was conducted using disc diffusion assay and highest inhibition zones were recorded against Bacillus subtilis (B. subtilis) (9.6 ± 0.5 mm) and Staphylococcus aureus (S. aureus) (8.6 ± 0.5 mm). The antioxidant potential was assessed via DPPH scavenging assay and highest percentage inhibition (89%) was observed at 100 μg/mL. Subsequently, different concentrations of A. roseum AgNPs were applied on the wheat seedlings to investigate its effects on different growth parameters. After applying AgNPs, significant increase in the fresh weight (FW), dry weight (DW), root length (RL), shoot length (SL), leaf number (LN) and chlorophyll content (CC) in wheat (Akbar-2019 variety) seedlings was observed in comparison to the control seedlings. Overall, A. roseum mediated synthesis of AgNPs was cost-effective and safe and can be used in agriculture, biomedical and other fields. RESEARCH HIGHLIGHTS: Synthesis and characterization of A. roseum AgNPs was done. Biogenic AgNPs revealed potent antibacterial and antioxidant potential. A. roseum mediated AgNPs also increases the growth and germination of wheat seedlings.