Figure 2.

Consumption of O₂ by the NAD(P)H oxidoreductase, its suppression by XTT, and the partial reversion of the suppression by SOD (pH 7.5). The addition of NADPH (200 μm), MD (100 μm), enzyme, XTT (100 μm), and SOD (100 μg mL⁻¹) is indicated by arrows. The measurements were performed in a 2-mL total volume containing 1.3 μg mL⁻¹ purified enzyme.