Figure 5. Analysis of enzymatic activity.

(A) Catalase, (B) Superoxide Dismutase and (C) Glutathione Reductase were measured in homogenates from liver (black bars) and gills (white bars) after exposure to CuO NP in different environmental salinities. FW0, fresh water; FW0.5, FW plus 0.5 mg·L⁻¹ CuO; FW5, FW plus 5 mg·L⁻¹ CuO; SW0, increasing salinity; SW0.5, SW plus 0.5 mg·L⁻¹ CuO; SW5, SW plus 5 mg·L⁻¹ CuO. Activity is expressed as mean nmol.ml⁻¹.min⁻¹.µg prot⁻¹ ± SEM. Groups with significant different means by Anova analysis are shown with ‡ (P value). Letters denote groups showing non significant differences by Tukey's post-test (P<0.05). n×treatment = 5.