Facile single step preparations of phyto-nanoparticles of iron in Calotropis procera leaf extract to evaluate their antifungal potential against Alternaria alternata

Green nanotechnology has become an emerging field for the control of plant disorders. In the current study, the leaf extract of Calotropis procera has been used as reducing and stabilizing agent and the preparation of iron nanoparticles has been optimised. For this purpose, the formation and morphological properties of green iron nanoparticles were investigated. The synthesized nanoparticles were characterized through fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) analysis. FTIR spectroscopy detected the presence of stabilising and reducing molecules such as O-H, C-H, O=C=O, C=O and C-O. XRD analysis confirmed the orthorhombic form and size (similar to 32 nm) of these nanoparticles. EDX analysis gave information about the presence of major elements in the samples while the spinal shaped morphology of prepared iron nanoparticles was described by SEM. After successful preparation, iron nanoparticles were evaluated for their potential antifungal activity. Using poisoned food technique, different concentrations of nanoparticles were used to assess growth inhibition of Alternaria alternata. Iron nanoparticles showed highly significant growth reduction and the maximum growth inhibition (87.9 %) was observed at 1.0 mg/mL concentration of nanoparticles. These results reveal that the iron nanoparticles, prepared in the leaf extract of C. procera are very efficient, cost-effective and eco-friendly. These proficient results suggest the large scale use of these green nanoparticles, as an effective alternative to chemical fungicide.