Characterization and biological activities of synthesized zinc oxide nanoparticles using the extract of Acantholimon serotinum

Abstract

The present study reports the synthesis of ZnO-NPs using Acantholimon serotinum extracts followed by characterization and evaluation of biological activities. Field emission scanning electron microscope revealed irregular spherical morphology with a size in the range of 20–80 nm. The X-ray diffraction analysis confirmed the synthesis of highly pure ZnO NPs with a hexagonal shape and a crystalline size of 16.3 nm. The UV-Vis spectroscopy indicates the synthesis of ZnO-NPs. FT-IR confirmed the presence of phytocomponents in the plant extract, which was responsible for nanoparticle synthesis. According to MTT results, the biosynthesized ZnO-NPs showed cytotoxic effects on human colon cancer Caco-2 (IC50: 61 µg/mL), neuroblastoma SH-SY5Y (IC50: 42 µg/mL), breast cancer MDA-MB-231 (IC50: 24 µg/mL), and embryonic kidney HEK-293 (IC50: 60 µg/mL) cell lines. Significant reactive oxygen species (ROS) generation was measured by the DCFH-DA assay after 24 h incubation with ZnO-NPs (200 µg/mL). ZnO-NPs caused apoptotic and necrotic effects on cells, which was confirmed by Annexin V-PE/7-AAD staining and 6.8-fold increase in pro-apoptosis gene Bax and 178-fold decrease in anti-apoptosis gene Bcl-2. The well diffusion method did not show effective growth inhibition activities of the ZnO-NPs against bacteria. In conclusion, the ZnO-NPs induce cytotoxicity in cell lines through ROS generation and oxidative stress.

Keywords

• zinc oxide nanoparticles
• acantholimon serotinum
• cytotoxicity
• anti-bacterial activity
• oxidative stress