Ten grams of macerated sample extract was diluted to 100 ml
with water and 1 ml of Folin–Ciocalteu reagent was added to
5 ml of this aliquot. After 6 min, 10 ml of Na2CO3 (7%) was
added and the volume was made up to 25 ml with distilled
water followed by incubation at room temperature for 90 min.
The absorbance was measured at 750 nm by spectrophotom-
eter (Shimadzu 1609, Tokyo, Japan) using gallic acid as
standard and distilled water as blank