2.6. Antioxidant Activity 2.6.1. DPPH Scavenging Activity
The DPPH (2,2-diphenyl-1-picryhydrazyl) assay was used to measure radical scavenging activity [15] and radical scavenging activity of the samples was reported as mg of ascorbic acid equivalents (AAE)/g DM sample. In brief, diluted sample extract or 0-0.04 mg/mL of ascorbic acid solution (1.5 ml) were mixed with 3 mL of 0.09 mg/mL DPPH solution and placed at room temperature for 5 min in dark. Then the absorbance was determined by a spectrophotometer at 517 nm. The assay was done in triplicate.