DPPH radical-scavenging capacity assay. The DPPH radical-scavenging activities of OLE, OFE, BPOL and BPOF were determined according to a previously reported method (Brand-Williams, Cuvelier, & Berset, 1995) with slight modifi- cations. A 0.5-mL aliquot of sample solution was mixed with 2.5 mL of a 0.5 mM methanolic solution of DPPH. The mixture was shaken vigorously and incubated for 30 min in the dark at room temperature. The absorbance was measured at 517 nm against a blank, using a UV–vis spectrophotometer. The results are expressed as the percent inhibition of the DPPH radical, which was calculated using the equation [(A0 − A1)/A0] × 100, where A0 is the absorbance of the DPPH solution without the sample. Vc and BHT were used as positive controls in this assay.