Antiradical activities of potent antioxidants by DPPH
The antioxidant activities were determined using DPPH as a
free radical. For each antioxidant, different concentrations
were tested (expressed as the number of moles of anti-
oxidant/mole DPPHe). Antioxidant solution in methanol
(0.1mL) was added to 3.9mL of a 6 × 10--Smol/L
methanol DPPH e solution. The decrease in absorbance was
determined at 515 nm at 0min, 1 rain and every 15 min until
the reaction 'reached a plateau. The exact initial DPPH*
concentration (CDPPH) in the reaction medium was calcu-
lated from a calibration curve with