The concentration
of antioxidant giving the same percentage inhibition of
absorbance of the radical cation at 734 nm as 1 mM
Trolox was calculated in terms of the Trolox equivalent
antioxidant activity at each specific time-point. To calculate
the TEAC, the gradient of the plot of the percentage
inhibition of absorbance vs. concentration plot for
the antioxidant in question is divided by the gradient of
the plot for Trolox. This gives the TEAC at the specific
time point and the calculated results for the flavonoids,
carotenoids, some plasma antioxidants, and a representative
fruit and beverage sample are given in Table 1.