Figure 2.

Medium free radical generation under conditions of increasing oxygen concentrations with vitamin C. The medium was mixed with DMPO and subjected to an ESR spin-trapping analysis. The ESR spectrum of the medium without vitamin C is shown, which revealed the presence of RO^· (A). The signal intensity of RO^· under conditions of an increasing oxygen concentration in the presence of 200 μmol/L of vitamin C was decreased (n = 4; B). # indicates RO^· spin adduct. *, P < .05, between the samples cultured with and without vitamin C; DMPO, 5,5-dimetyl-1-pyrroline-N-oxide; ESR, electron spin resonance; RO·, alkoxyl radical.