2.4.2. Anti-oxidant activity
2.4.2.1. DPPH radical scavenging activity. Free radical scavenging activity
was determined with a DPPH radical assay, performed according to the
modified method described by Brand-Williams et al. (1995). Briefly,
100 μM of DPPH in ethanol was prepared and 1 ml of this solution
was added to a test sample (4 ml). The reaction mixture was shaken
well and incubated for 30 min at room temperature. The absorbance
of the resulting solution was read at 517 nm using a UV–Vis spectrophotometer
(Carry 100 UV–VIS, Agilent Technologies, Santa Clara,
California, USA) against a blank and DPPH radical scavenging activity
was expressed as μ mol of trolox equivalents (TE) g sample from a
standard curve developed with Trolox. All determinations were
performed in triplicate.