2.2.2 Determination of antioxidant capacity and total phenolic
content
Radical- scavenging activity of Camelina seed was detrmined by 2,
2-diphenyl-1-picrylhydrazyl radical (DPPH) assay according to Hanato et
al., 1998 method. In short, the different concentrations of methanol
extraction (2ml) were added to the 200µM DPPH solution. The mixture was
incubated in room temperature for 30 min. The absorbance value of
solution was determined at 517nm using Shimadzu UV- Vis
spectrophotometer, Japan. The standard curve of Trolox was prepared for
the measurement of antioxidant capacity.
The total phenolic (TPC) content was measured by the Folin-Ciocalteu
method (Velioglu etal., 1998). In short, the TPC was extracted from
seeds (0.1 gr powder) with 10 ml 80% methanol at 70°C for 3h. 2.5ml of
Folin-Ciocateu reagent was added to 0.5 ml methanolic extract and
incubated in room temperature for 10 min and centrifuged in 5000 rpm for
20 min. Supernatant was incubated at 90°C for 5min when 2.5 ml
Na2Co3 solution (7.5%) was added. The
absorbance value of mixture read at 765 nm and TPC was determined by a
standard curve of Gallic acid.