One gram of sample was taken along
with 29 ml methanol, shaken vigorously, and centrifuged at
5000 rpm for 15 min at 4 8C. To that filtrate 0.5 ml DPPH
(Diphenyl picrylic hydrazine) reagent was added and incubated
for 45 min in dark. Methanol was taken as blank and 3 ml
methanol with 0.5 ml DPPH reagent was taken as control. The
absorbance was measured using spectrophotometer (Shimadzu
1609, Tokyo, Japan) at 517 nm. The antioxidant activity
was calculated using the following formula