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


The EC50 value of extract A is higher than that of extract B
The EC50 value of extract A is
The results obtained by the DPPH° test are directly applicable to food products
Extract A contains 50% (w/w) of antioxidant molecules, while extract B has only 10%. It can therefore be considered that the antioxidant molecules in extract B are overall more effective than those in extract A
Since extract B is half the price of extract A, it would be the best of the two options for stabilizing food products
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