Zizyphus mauritiana Fruit Extract-Mediated Synthesized Silver/Silver Chloride Nanoparticles Retain Antimicrobial Activity and Induce Apoptosis in MCF-7 Cells through the Fas Pathway

Recently, green synthesis of silver/silver chloride nanoparticles (Ag/AgCl-NPs) has gained a lot of interest because of the usage of natural resources, rapidness, eco-friendliness, and benignancy. Several researchers reported that silver-based biogenic NPs have both antimicrobial and anticancer properties. In the present study, Ag/AgCl-NPs were synthesized from Zizyphus mauritiana fruit extract, and their antibacterial, antifungal, and antiproliferative mechanisms against human MCF-7 cell lines were evaluated. Synthesis of Ag/AgCl-NPs from the Z. mauritiana fruit extract was confirmed by the changes of color and a peak of the UV–visible spectrum at 428 nm. The nanoparticles were characterized by transmission electron microscopy, energy dispersive X-ray, X-ray powder diffraction, thermal gravimetric analysis, atomic force microscope, and Fourier transform infrared. Antibacterial activity was checked against four pathogenic bacteria and two fungi. Cytotoxicity was checked against human breast cancer cell line (MCF-7) and mice Ehrlich ascites carcinoma (EAC) cells by MTS assay and clonogenicity assay. Cell morphology of the control and nanoparticle-treated MCF-7 cells were checked by Hoechst 33342, YF488-Annexin V, and caspase-3 substrates. The level of reactive oxygen species (ROS) was studied by using 2′,7′-dichlorofluorescein-diacetate staining. Real-time polymerase chain reaction was used for gene expression. Synthesized nanoparticles were heat stable cubic crystals with an average size of 16 nm that contain silver and chlorine with various functional groups. The synthesized Ag/AgCl-NPs inhibited the growth of three pathogenic bacteria (Bacillus subtilis, Shigella boydii, and Escherichia coli) and two fungi (Aspergillus niger and Trichoderma spp.). Ag/AgCl-NPs inhibited the growth of MCF-7 and EAC cells with the IC50 values of 28 and 84 μg/mL, respectively. No colony was formed in MCF-7 cells in the presence of these nanoparticles as compared with control. Ag/AgCl-NPs induced apoptosis and generated ROS in MCF-7 cells. The expression level of FAS, FADD, and caspase-8 genes increased several folds with the decrease of PARP gene expression. These results demonstrated that the anti-proliferation activity of Ag/AgCl-NPs against MCF-7 cells resulted through ROS generation and induction of apoptosis through the Fas-mediated pathway.