Fig. 5. Effects of propofol medium chain triglyceride/long chain triglyceride (MCT/ LCT) on superoxide (O^2·−) generation. (  A ) Electron spin resonance spin trapping measurement of O^2·−generation from xanthine oxidase (0.1 U/ml) and xanthine (362 μm) in 0.1 m phosphate-buffered saline (pH 7.2) as spin trap 5,5-dimethyl-1-pyrroline-  N -oxide (440 mm) (  a ) in the absence of propofol MCT/LCT (control) (  b ) with pretreatment of superoxide dismutase (150 U/ml) to xanthine oxidase (  c ) with propofol MCT/LCT pretreatment (original liquid; 5,609 μm). Signals appearing at either side of the electron spin resonance spectra correspond to manganese oxide installed in the cavity as a reference. In  B , we report the effects of propofol MCT/LCT (original liquid; 5,609 μm) on O^2·−generation from xanthine oxidase and xanthine. The signal intensity of the second peak of the spectrum was normalized as the relative height against the standard's signal intensity of the manganese oxide marker. Data are presented as mean ± SD of quadruplicate experiments.