Effect of Silver nanoparticles exposure on oxidative stress in blue swimmer crab (Portunus pelagicus)

Nanotechnology is a new technology that has many potential environmental effects on living organisms, especially aquatic species. This study was carried out to determine the median lethal concentrations (LC 50 ) of silver nanoparticles and its effect on the antioxidant system in the hepatopancreas and muscle tissue of blue swimmer crab ( Portunus pelagicus ). The LC 50 value was determined according to the OECD standard method and after that, the crabs were exposed to sublethal silver nanoparticles concentrations (equivalent to 25, 50 and 75% LC 50 AgNPs) for 14 days. To measure the activity of catalase, glutathione superoxide dismutase, glutathione peroxidase, total antioxidant capacity and malondialdehyde, crab were sampled on days 3, 7 and 14. According to the results, the 96 h LC 50 value of AgNPs was 13.65 mg/L. In both hepatopancreas and muscle tissue, except glutathione and glutathione peroxidase, the level of catalase, superoxide dismutase and total antioxidant capacity of crabs exposed to 50% LC 50 of AgNPs were significantly decreased as compared to the control (p < 0.05). MDA level in hepatopancreas significantly increased in crab exposed to 50% LC 50 of AgNPs compared to all tested concentration and control group (p < 0.05), but not in the muscle. In general, crabs exposed to 50% LC 50 of AgNPs showed a significant decrease in the levels of catalase, superoxide dismutase and total antioxidant capacity, except in MDA level where it was significantly increased which was indicate that a dose of 50% LC 50 of AgNPs had a deleterious effect on the hepatopancreas antioxidant system of blue swimmer crab.