Determination of the activity of an antioxidant by the DPPH° assay
A company that produces natural antioxidant extracts wishes to evaluate the effectiveness of two of their new products: extract A and extract B. To this end, they decide to evaluate their antiradical activity using the DPPH° test by establishing, for each extract, the reaction kinetics for different concentrations. From the resulting curves, the percentage of residual DPPH° on the plateau is determined. The values obtained are reported in the following table:
Concentration in antioxidant extract (g/L) | EXTRACT A: residual DPPH° at the plateau (%) | EXTRACT B: residual DPPH° at the plateau (%) |
0 | 100 | 100 |
0.25 | 74.6 | 84.1 |
0.5 | 53.2 | 72.3 |
1 | 18.5 | 48.6 |
2.5 | 8.7 | 19.2 |
10 | 7.1 | 5.2 |
20 | 3.9 | 4.1 |
40 | 3.8 | 4.0 |