reduction of the DPPH radical was measured by monitoring the
decrease of absorption at 517 nm. DPPH scavenging effect was calculated
as the percentage of DPPH discoloration using the following
equation: % scavenging effect = [(ADPPH − AS)/ADPPH]
×100, where AS is the absorbance of the solution when the sample extract has
been added at a particular level and ADPPH is the absorbance of
the DPPH solution.