Effects of Di-2-ethylhexyl phthalate on growth, lipid peroxidation and antioxidative enzyme activity in Dunaliella salina

Abstract

Di-2-ethylhexyl phthalate (DEHP) is a toxic organic compound. It has been shown to exert negative effects on non-targeted aquatic organisms. In order to study the toxicological effects of DEHP on marine microalgae, we investigated cell growth, oxidative damage and antioxidant enzyme activities of Dunaliella salina under DEHP treatment. After exposure to DEHP of 10 to 800 mg/L for 7 days, D. salina growth was gradually inhibited with the increase in DEHP concentration. After D. salina was exposed to 400 mg/L DEHP for 4 days, the contents of malondialdehyde and hydrogen peroxide in D. salina were significantly increased as compared with those in the control group. After 6 days of exposure to DEHP at 10 to 400 mg/L, glutathione peroxidase activity in D. salina was significantly reduced in the 10 and 40 mg/L DEHP groups. Exposure of D. salina to 100 to 400 mg/L DEHP resulted in significantly higher inhibition of total superoxide dismutase in D. salina (p<0.05), and copper-zinc superoxide dismutase of D. salina was significantly inhibited compared with that of the control group (p<0.01). The results showed that DEHP exposure can damage the antioxidant defense system and cause cell death in D. salina.