Changes in Antioxidant and Detoxification Systems of the Freshwater Amphipod Gammarus pulex Exposed to Congo Red

In this study, it is aimed to investigate the changes in glutathione S-transferase and cytochrome 1A1 enzymes with malondialdehyde levels in Gammarus pulex exposed to congo red. G. pulex was exposed to synthetic solutions containing 20, 10, 5 mg/L of congo red during 96 hours. Glutathione S-transferase and cytochrome 1A1 enzyme activities were determined by using ELISA kit, malondialdehyde levels were determined spectrophotometrically. Glutathione S-transferase activities groups increased in all application groups during 24 and 96 hours compared to control (P<0.05). After exposure to congo red, cytochrome 1A1 activity was decreased during 24 and 96 hours in all application groups compared to control groups (P<0.05). Malondialdehyde levels increased in all groups after congo red exposure compared to control during 24 hours (P<0.05), after 96 hours increased in group A, decreased in groups B and C (P<0.05). Our results show that congo red may cause oxidative stress by producing reactive oxygen species. In conclusion, changes in antioxidant enzymes and malondialdehyde levels suggest that congo red can be used as potential sensitive biomarkers in the assessment of environmental toxicity.