ABSTRACT
This study was designed to prepare silver, zinc and gold nanoparticles
(NPs), AgNPs, ZnNPs and AuNPs, by biosynthesis technique using methanolic
extract of Rhanterium epapposum flowers using AgNO3, Zn (CH3CO2)2 and HAuCl4·3H2O as starting materials. The physical
properties of the formed NPs were characterized by ultraviolet spectroscopy (UV),
X-ray diffraction (XRD), transmission electron microscopy and Fourier
transformed infrared spectroscopy (FTIR). The results revealed that, AgNPs were
homogeneous and spherical in shape, with average diameter 16.3 nm. While, ZnNPs
were approximately triangle and hexagonal shaped, with average diameter 23.5 nm.
Most of the synthesized AuNPs were spherical in shape with average diameter
17.9 nm. The antifungal activity of different concentrations of the formed
AgNPs, ZnNPs and AuNPs was tested against two human pathogens: Candida albicans and Aspergillus melleus and one plant pathogenic fungus: Phoma exigua, using agar diffusion
assay. The best results recorded by 120 μg/ml AgNPs against the human pathogen: C. albicans where the inhibition zone was 23.5 mm.
Additionally, the cytotoxicity of the tested NPs was evaluated against Breast
adenocarcinoma (MCF-7), Hepatocellular carcinoma (HepG-2) and colorectal carcinoma (HCT 116) human cell
lines. The most toxic was AuNPs where the IC50 against MCF-7, HepG2 and HCT116
was 55.02, 66.44 and 169.87 μg/mL respectively.