The absorbance was measured at 725 nm using a spectrophotometer (Hewlett Packard 8452A, Diode Array, USA) and the results were expressed in gallic acid equivalents (GAE; mg/100 g fresh mass) using a gallic acid (0–0.1 mg/mL) standard curve. Additional dilution was done if the absorbance value measured was over the linear range of the standard curve.