Antioxidant activities of natural vitamin E formulations.

The antioxidant activities of natural d-α-tocopherol, mixed tocopherols and tocotrienols, and formulations comprising all forms of vitamin E, providing 400IU, were determined employing an improved oxygen radical absorbance capacity (ORAC) assay using fluorescein (FL) as the fluorescent probe, randomly methylated β-cyclodextrin (RMCD), 2, 2'-azobis(2-amidino-propane)dihydrochloride (AAPH) as the peroxyl radical generator, and Trolox as the standard in 75mM phosphate buffer. The antioxidant activities, expressed in μmol Trolox equivalent per gram, of d-α-tocopherol (87%), mixed tocopherols (70%), and tocotrienols (30%) were found to be 1, 293, 1, 948, and 1, 229, respectively. Some of the vitamin E formulations showed antioxidant activities superior to d-α-tocopherol.