The resulting blue–green colored ABTS•+ solution was adjusted
to an absorbance of 0.70 ± 0.02 at 734 nm. Briefly, 0.5 ml
of the extract was added to 1 ml of the ABTS•+ solution and
thoroughly mixed. After 6 min, the absorbance was measured
at 734 nm against a control. The values were expressed
as an IC50 value, which is the concentration of the extract that
scavenges 50% of the ABTS•+.