The reducing activity of the extracts was measured using the
method explained by Balakrishnan et al. (2011). Briefly, 100 L
of the extract was added to 900 L of phosphate buffer (0.2 M,
pH 6.6) and 900 L of 1% potassium ferric cyanide; the solution
was mixed thoroughly and kept in incubation at 50 °C
for 20 min. Nine hundred microlitres of 10% TCA was added,
mixed and centrifuged at 7000 g for 10 min. From the supernatant
900 L of solution was mixed with 900 L of distilled
water and 900 L of 0.1% FeCl3. The solution was mixed and
reducing activity was measured by using a spectrophotometer
at 700 nm.