Ferric reducing power
It was carried out according to Barros et al[18]. Briefly,
2.5 mL of extract of varying concentrations were incubated
at 50 °C for 20 min together with 2.5 mL of 200 mmol/L of
Na-phosphate buffer ( pH 6.6) and 2.5 mL of 1% potassium
ferricyanide. After incubation, 2.5 mL of 10% trichloroacetic
acid was added to the reaction mixture and centrifuged
at 1 000 r/min for 8 min. About 5 mL of supernatant was
extracted and made up to 10 mL with deionized water.
To this solution, 1 mL of 0.1% ferric chloride was added
and absorbance was measured at 700 nm. Butylated
hydroxyanisole (BHA) was used as a standard.