Developmental toxicity and biochemical and biomarker in the zebrafish (Danio rerio) embryo exposed to biosynthesized cadmium oxide nanoparticles

Abstract

Cadmium oxide nanoparticles (CdO-NPs) play an important role in health applications due to their antibacterial properties. However, ecotoxicological investigations of these NPs and their adverse effects on aquatic organisms are necessary to protect the environment. Zebrafish is widely used as a model organism to explore toxic effects at multiple levels of integration. Hence, the objective of this work was to pursue possible harmful impacts of CdO -NPs that have been produced through biosynthesis, utilizing extract from the lily plant Gloriosa superba leaves, on the growth and biochemical changes in zebrafish (Danio rerio) embryos and larvae. UV, SEM, TEM, FTIR, EDAX, DLS, and ZETA-potential techniques were employed to examine the structure and morphology of the biosynthesized CdO-NPs. The identification of bioactive chemicals from the leaf extract of G. superba was conducted using GC-MS. To study the in vivo toxicity of CdO-NPs, zebrafish embryos and larvae were treated with two different concentrations of G. superba leave extract (0.5 and 1.0 mg/mL) at 96 hours after fertilization (hpf). Bended tail, pericardial edema, shortened yolk sac extension, scoliosis, and damaged eyes were observed in the CdO-NPs treated groups. In addition, there was a considerable decrease in the levels of superoxide dismutase (SOD), catalase (CAT), glutathione S-transferases (GST), and lipid peroxidation (LPO). The CdO-NPs treated groups showed significant alterations in biochemical markers, including protein levels, glucose levels, and acetylcholinesterase (AChE) activity. Overall, our findings indicated that CdO-NPs induced a dose-dependent toxicity in zebrafish embryos. The investigated parameters serve as reliable biomarkers for the surveillance of CdO-NPs in aquatic ecosystems and their impact on living animals.