Study of the toxic effects of samarium doped zinc oxide (SM/ZnO) nanoparticles on some growth and developmental indices of the green alga Chlorella vulgaris

A nanoparticle is considered as a material with at least one dimension of less than 100 nm. The increasing use of nanoparticles in the last two decades has made it necessary to study the potential effects of these substances on aquatic environments and ecosystems. Microalgae are commonly used for assessing the toxicity of toxins and nanoparticles in aquatic ecosystems. This research was conducted to investigate the toxicity of Samarium zinc oxide nanoparticles on Chlorella vulgaris. In this study, ZnO nanoparticles were doped by samarium by hydrothermal technique and their characteristics were determined using transmission electron microscopy (TEM) and Energydispersive X-ray spectroscopy (EDS). Then, the toxicity of (Sm/ZnO) nanoparticles on some growth and development indices of the green alga Chlorella vulgaris wereinvestigated. Under the influence of nanomaterials, oxidative stress is produced, resulting in the production of reactive oxygen species (ROS). Increasing activity of ascorbate peroxidase (APX) and superoxide dismutase (SOD) and decreasing activity of catalase (CAT) as antioxidant enzymes in treated algae by nanoparticles were observed compared to control. Moreover, the study of growth changes in different concentrations of nanoparticles was carried out and by the increasing concentration of nanoparticles growth of alga was decreased. By the increasing concentration of nanoparticles, the total phenol and flavonoid content and chlorophyll a, b, total chlorophyll content, as well as carotenoids, decreased in treated samples compared to control. Also, using scanning electron microscope (SEM), the effect of nanoparticles on the shape of algae was observed

کلیدواژه ها:

Nanoparticles ، Cellular toxicity ، Photosynthetic pigments ، Antioxidant enzymes ، Chlorella vulgaris