Antioxidant capacity of CISE was determined by measuring the
DPPH radical scavenging activity. An aliquot of the extracts (0.5 mL)
was mixed with DPPH solution in ethanol (0.5 mL, 0.1 mM). The
reaction mixture was shaken vigorously and allowed to stand in the
dark for 30 min at room temperature, after which the absorbance
at 517 nm was measured. To calculate the DPPH radical scavenging
activity, trolox standards at different concentrations (0–0.08 mM)
were used.