Comparison of the effect of copper oxide and iron oxide nanoparticles on oxidative stress in Nannochloropsis oculata

In this study, the effects of various concentrations (5, 10, 50, 100 and 200mg/L) of copper oxide (CuO) and iron oxide (Fe2O3) nanoparticles (NPs) on growth, lipid peroxidation and activity of catalase and ascorbate peroxidase enzymes were investigated. The results showed that concentrations of more than 5mg/L of CuO-NPs and more than 10mg/L of Fe2O3-NPs reduced the growth of Nannochloropsis oculata. The content of aldehydes in response to some of concentrations of both metal oxide nanoparticles significantly increased compared to control (P<0.05(.  However, the increase of aldehydes in response to CuO-NPs was higher than Fe2O3-NPs. The activity of ascorbate peroxidase increased significantly in response to both nanoparticles, but the effect of CuO-NPs on the activity of this enzyme was higher than that of Fe2O3-NPs. Catalase activity showed a significant increase in response to CuO-NPs, but Fe2O3-NPs decreased the activity of this enzyme. The results showed that the toxicity of CuO-NPs in N. oculata was much more severe than Fe2O3-NPs.