A spectrophotometric method has been developed for the quantitative determination of antioxidant capacity.
The assay is based on the reduction of Mo(VI)to Mo(V) by the sample analyte and the subsequent formation of
a green phosphate/Mo(V) complex atacidic pH. The method has been optimized and characterized with
respect to linearity interval, repetitivity and reproducibility, and molar absorption coefficients for the
quantitation of several antioxidants, including vitamin E. The phosphomolybdenum method, in combination
with hexane monophasic extraction, has also been adapted for the specific determination of vitamin E in seeds.
The results obtained with the proposed method were validated by comparison with a standard HPLC method.
The phosphomolybdenum method is routinely applied in our laboratory to evaluate the total antioxidant
capacity of plant extracts and to determine vitamin E in a variety of grains and seeds, including corn and
soybean