Antioxidant activities of natural vitamin E formulations.
The antioxidant activities of natural d-alpha-tocopherol, mixed tocopherols and tocotrienols, and formulations comprising all forms of vitamin E, providing 400 IU, were determined employing an improved oxygen radical absorbance capacity (ORAC) assay using fluorescein (FL) as the fluorescent probe, randomly methylated beta-cyclodextrin (RMCD), 2,2'-azobis(2-amidino-propane)dihydrochloride (AAPH) as the peroxyl radical generator, and Trolox as the standard in 75 mM phosphate buffer. The antioxidant activities, expressed in micromol Trolox equivalent per gram, of d-alpha-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-alpha-tocopherol.
Naguib
Yousry
Y
Soft Gel Technologies, Inc., 6982 Bandini Blvd., Los Angeles, California 90040, USA. yousryn@soft-gel.com
Hari
Siva P
SP
Passwater
Richard
R
Huang
Dejian
D
D000578:Amidines / Q000378:metabolism; D000975:Antioxidants / Q000032:analysis / Q000378:metabolism*; D002839:Chromans / Q000378:metabolism; D003505:Cyclodextrins / Q000378:metabolism; D019793:Fluorescein / Q000032:analysis; D005609:Free Radicals / Q000378:metabolism; D006801:Humans; D007202:Indicators and Reagents; D017601:Oxygen Compounds / Q000378:metabolism*; D010545:Peroxides / Q000378:metabolism; D024505:Tocopherols / Q000737:chemistry / Q000378:metabolism; D024508:Tocotrienols / Q000737:chemistry / Q000378:metabolism; D014810:Vitamin E / Q000031:analogs & derivatives / Q000737:chemistry / Q000378:metabolism*
D000578:Amidines; D000975:Antioxidants; D002839:Chromans; D003505:Cyclodextrins; D005609:Free Radicals; D007202:Indicators and Reagents; D017601:Oxygen Compounds; D010545:Peroxides; D024508:Tocotrienols; D014810:Vitamin E; C049375:perhydroxyl radical; C046728:2,2'-azobis(2-amidinopropane); D024505:Tocopherols; C010643:6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid; D019793:Fluorescein