Biological synthesis of silver nanoparticles using Rheum ribes and evaluation of their anticarcinogenic and antimicrobial potential: A novel approach in phytonanotechnology

This paper reports the anticarcinogenic and antimicrobial properties of silver nanoparticles (Ag NPs) obtained by green synthesis using the extract of Rheum ribes (R. ribes), a medicinal plant. For the synthesis of Ag NPs, the ethanolic extracts of R. ribes were used as a reducing as well as the stabilizing agent. For the characterization of Ag NPs, advanced analytical methods such as transmission electron microscopy (TEM), X-Ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and UV-vis spectrophotometry were performed. The synthesized Ag NPs obtained from R. ribes were evaluated as a cytotoxic agent against MDA-MB-231 breast carcinoma cell line. The IC₅₀ values of the nanoparticles were ranged from 165 to 99 μg/mL against MDA-MB 231 cell line for 24 h and 48 h, respectively. The results show that the use of Ag NPs at low concentrations show the toxic effect in the cancer cells. In addition, the results of experiments on gram-positive (Staphylococcus aureus (S. aureus), Methicillin-resistant Staphylococcus aureus (MRSA) and Bacillus subtilis (B. subtilis)) and gram-negative (Escherichia coli (E. coli)) bacteria showed that the Ag NPs had high antimicrobial activity. The results suggest that Ag NPs can be developed as potential anticancer and antibacterial agents.

Biogenic platinum nanoparticles using black cumin seed and their potential usage as antimicrobial and anticancer agent

Herein, the biogenic platinum nanoparticles (Pt NPs) were synthesized by using black cumin seed (Nigella sativa L.) extract as a reducing agent. The biogenic platinum nanoparticles synthesized by black cumin seed extract was characterized in detail by Transmission Electron Microscopy (TEM), UV-vis spectrophotometer, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS). According to TEM analysis, Pt nanoparticles have spherical shapes and sizes between 1-6 nm. Moreover, the biogenic Pt NPs was assessed for its cytotoxicity effect on MDA-MB-231 breast and HeLa cervical cancer lines and their antibacterial effect against selected strains of gram-positive and negative bacteria. The cytotoxicity and bacterial tests showed the effectiveness of biogenic Pt nanoparticles. Dose-dependent toxicity effects were shown in the MDA-MB-231 breast and HeLa cervical cancer lines (IC50: 36.86 μg/mL and 19.83 μg/mL, respectively). In addition, Pt NPs showed high zone diameters against gram-positive and gram-negative bacteria at concentrations of 100 and 500 μg/ml. These results contribute to the development of the pharmaceutical industry as a potential antibacterial and anticancer agent.