The total phenolic content (TPC) in each fracton was determined by the Folin–Ciocalteu
method (Singleton, Orthofer, & Lamuela-Raventos,1999). One milliliter of extract in methanol was mixed with 1 ml of 3-fold-diluted Folin–Ciocalteu phenol reagent. Two milliliters of 35% sodium carbonate solution and distilled water were added subsequently. The mixture was incubated
for 30 min and the absorbance was recorded at 700 nm by a spectrophotometer