Oxidative Stress In Zebrafish Embryo/Larvae And BSA Conformation Impact By Butachlor

Butachlor is used widely. Once released into the environment, it exerts toxic effects on non-target organisms and even humans via food chain. Therefore it's necessary to evaluate the toxicity of butachlor accurately. Zebrafish has been one of the most used models for toxicological studies for its features. Reports have confirmed that xenobiotic could induced oxidative stress in zebrafish, leading to oxidative damage. Compared to the studies on toxicity, the effect of antioxidant is somehow ignored.The aim of this study is to study about the effect of butachlor on the development, oxidative stress of zebrafish and the structural changes of BSA. Vitamin C(Vc) is a common soluable antioxidant, offen used as an additive in food and feed. For the first time, the joint effect of Vc and butachlor on zebrafish was studied, and the butachlor-BSA interaction was studied using spectroscopic methods. The details were as follows:(1) The acute toxicity of butachlor on zebrafish embryos was evaluated. After 96 hpf exposure, butachlor would lead to malformation and death of zebrafish. Physical abnormalities like PE, YSE and crooked body were observed. The toxicity effects were dose-dependent;(2) The joint effect of Vc and butachlor on the development of zebrafish embryo was studied. After 72 hpf exposure, results show that Vc could relieve the morality and malformation caused by butachlor;However Vc could increase the burden of organism when it exists along;(3) The joint effect of Vc and butachlor on the antioxidant system of zebrafish was also evaluated. The results showed that butachlor caused the increase of ROS, leading to lipid peroxidation, and dose-dependent toxicity was observed. While lower concentration of butachlor exerted slight oxidative stress, inducing the increased enzymatic activity, high levels of butachlor led to oxidative damage and inhibit enzymatic activity. The metabolic rate was also changed. Vc would decrease the increment of ROS and MDA caused by butachlor significantly and maintain the enzymatic activity at steady levels, indicating that vitamin C helped in the process of ROS cleaning, and protecting cells from oxidative damage. But the protective process was with higher energy consumption;(4) The interaction between butachlor and BSA was studied using spectroscopic methods. Results suggested that butachlor-BSA complex was formed resulting in a static quenching of BSA. Van der Waals force and hydrogen bond were the major forces contributed to the interaction. Butachlor changed the microenvironment around Trp in BSA and the structure of BSA was changed because of the folded peptide chain.