where Y is the extent of protection against protein oxidation, Ds is the density of the band of BSA treated with the sample (treated or not with a-amylase) (i.e., BSA incubated with AAPH and methanolic sample extract), Dt is the density of the negative control (BSA incubated with AAPH in the absence of methanol extracts of samples),and Dc, (standard density, defined as the density of the positive control whose relative density is set to 1). All the experiments were carried out in triplicate.