The Antimicrobial, Antioxidant, and Anticancer Activity of Greenly Synthesized Selenium and Zinc Composite Nanoparticles Using Ephedra aphylla Extract

Abstract

The current work aimed to synthesize selenium and zinc nanoparticles using the aqueous extract of Ephedra aphylla as a valuable medicinal plant. The prepared nanoparticles were characterized by TEM, zeta potential, and changes in the phytochemical constituents. Hence, the phenolic, flavonoid, and tannin contents were reduced in the case of the prepared samples of nanoparticles than the original values in the aqueous extract. The prepared extract of Ephedra aphylla and its selenium and zinc nanoparticles showed high potency as antioxidant agents as a result of the DPPH^• assay. The samples were assessed as anticancer agents against six tumor cells and a normal lung fibroblast (WI-38) cell line. The selenium nanoparticles of Ephedra aphylla extract revealed very strong cytotoxicity against HePG-2 cells (inhibitory concentration (IC₅₀) = 7.56 ± 0.6 µg/mL), HCT-116 cells (IC₅₀ = 10.02 ± 0.9 µg/mL), and HeLa cells (IC₅₀ = 9.23 ± 0.8 µg/mL). The samples were evaluated as antimicrobial agents against bacterial and fungal strains. Thus, selenium nanoparticles showed potent activities against Gram-negative strains (Salmonella typhimurium, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Escherichia coli), Gram-positive strains (Bacillus cereus, Listeria monocytogenes, Staphylococcus aureus, and Staphylococcus epidermidis), and the fungal strain Candida albicans. In conclusion, the preparation of nanoparticles of either selenium or zinc is crucial for improved biological characteristics.

Keywords: Ephedra aphylla; antimicrobial; antioxidant; aqueous extract; cancer; cytotoxic; nanoparticles; oxidation; selenium; zinc.

Figure 1

TEM micrographs of the prepared selenium and zinc nanoparticles of the extract of Ephedra aphylla. (a) TEM micrographs and size distributions for selenium nanoparticles synthesized by Ephedra aphylla extract at a 200 nm magnification value. (b) TEM micrographs and size distributions for zinc nanoparticles synthesized by Ephedra aphylla extract at a 200 nm magnification value.

Figure 2

Zeta potential charts of the prepared selenium and zinc nanoparticles of the extract of Ephedra aphylla. (a) Zeta potential of the prepared nano selenium synthesized by Ephedra aphylla extract. (b) Zeta potential of the prepared nano zinc synthesized by Ephedra aphylla extract.

Figure 3

Comparison of the IC₅₀ values of the tested samples against human cancer cells.

Figure 4

Comparison of the inhibition percentage with the percent of average relative viability of tumor and normal cells at different concentrations. Where: (a,b) for Doxorubicin, (c,d) for Ephedra aphylla extract, (e,f) for Ephedra aphylla + SeNPs, (g,h) for Ephedra aphylla + ZnNPs, (i,j) for Selenium sulfate solution and (k,l) for Zinc sulfate solution.

Figure 4

Comparison of the inhibition percentage with the percent of average relative viability of tumor and normal cells at different concentrations. Where: (a,b) for Doxorubicin, (c,d) for Ephedra aphylla extract, (e,f) for Ephedra aphylla + SeNPs, (g,h) for Ephedra aphylla + ZnNPs, (i,j) for Selenium sulfate solution and (k,l) for Zinc sulfate solution.

Figure 5

Photos of the antimicrobial activity of the wild Ephedra aphylla water extract and the synthesized nanoparticles using well diffusion assay against different pathogenic microbial starins as presented in subfigures (a): Salmonella typhimurium, (b): Bacillus cereus, (c): Klebsiella pneumoniae, (d): Escherichia coli, (e): Staphylococcus epidermidis, (f): Pseudomonas aeruginosa, (g): Staphylococcus aureus, (h): Listeria monocytogenes and (i): Candida albicans where, Code 1 = Ephedra aphylla aqueous extract; Code 1 Se = greenly synthesized selenium nanoparticles; Code 1 Zn = greenly synthesized zinc nanoparticles.