Total phenols
The CA extracts were analyzed for total phenolics using the Folin–
Ciocalteu (F–C) assay (Escarpa & Gonzalez, 2001) with slight modifications.
Suitable aliquots of extracts were taken in a test tube and the
volume was made to 0.5 ml with distilled water followed by the
addition of 0.25 ml F–C (1 N) reagent and 1.25 ml sodium carbonate
solution (20%). The tubes were vortexed and the absorbance recorded
at 725 nm (SHIMADZU, Model: UV-1700 PharmaSpec, Japan) after
40 min. The amount of total phenolics was calculated as tannic acid
equivalent from the calibration curve using standard tannic acid solution
(0.1 mg/ml).