Ferric reducing antioxidant power (FRAP)The FRAP assay method of Benzie and Strain14 was modified to determine antioxidant activity using trolox as the standard. The FRAP reagent was prepared using 300mMacetate buffer, pH 3.6 (3.1 g sodium acetate trihydrate, plus 16 ml glacial acetic acid made up to 1 l with distilled water). The acetate buffer was mixed with 10 mM TPTZ (2,4,6-tri(2-pyridyl)-s-triazine) in 40 mM HCl and 20 mM FeCl3 6H2O at the ratio of 10:1:1 to produce the working reagent. For assays, 3950 µl of freshly prepared FRAP reagent was mixed with 50 µl sample,standard, or blank and incubated for 30 min before reading absorbance at 595 nm.