Ethyl alcohol, potassium persulfate and Folin–Ciocalteu reagent were obtained from Merck (Darmstadt, Germany). Trolox(6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) were purchased from Sigma–Aldrich (St. Louis, MO, USA).