2.4.3.1. DPPH radical scavenging spectrophotometric assay. The DPPH
radical-scavenging activity of pumpkin seeds was determined
according to the method proposed by Yen and Chen (1995). To
each supernatant (0.5 ml), DPPH and ethanol were added in the
amount of 0.5 and 1.5 ml, respectively. The mixture was shaken
and allowed to stand at room temperature for 10 min. Antioxidant
capacity was measured by recording the absorbance at 517 nm
using a spectrophotometer (Shimadzu UV-2401 PC). Ethanol was
used as the blank. All determinations were performed in triplicate