After 8 min of equilibrium, 750 lL of 20% Na2CO3 and 950 lL of H2O were added to the extracts; after incubation for 30 min at room temperature, the absorbance was read at 765 nm with a UV–Vis spectrophotometer PerkinElmer Lambda 11. Concentration of total soluble phenols compound was calculated using a standard curve of aqueous solutions of gallic acid (0–10 ppm) and expressed as mg gallic acid equivalents (GAE)/100 g dry weight (DW).