The mixtures were shaken and
kept in the dark at room temperature for 30 min.
Absorbance values
of the final solutions were recorded at 515 nm using a spectrophotometer
(Analytik Jena UV-Vis L 40, Germany) with respect to
control solution (80% MeOH instead extract in DPPH solution).
The
antioxidant activity of the samples was expressed as percentage
inhibition of the DPPH radical which was calculated by using the
following