Antioxidant potential of individual or combined dietary supplements

An antioxidant may be defined as a substance that when present at low concentrations, compared with those of the oxidizable substrate, significantly delays or inhibits its oxidation [1]. Nowadays there are several commercial dietary supplements which claim for antioxidant activity. In this work, the antioxidant activity (AA) of 17 dietary supplements (Table 1) available in different formulations (pills, capsules or bags), was evaluated by in vitro assays: scavenging activity of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals, reducing power (RP) and inhibition of lipid peroxidation by preventing the formation of thiobarbituric acid reactive substances (TBARS). Furthermore, different combinations (8+10+17, 8+10, 8+17 and 10+17) of some samples were also tested in order to obtain potential synergistic effects. Linear discriminant analysis (LDA) was used to categorize the condensed formulations (pills and capsules), the infusion bags and the combined samples, according with their antioxidant activity. The Advanced Antioxidant Formula (AAF; sample 8) proved to have the highest antioxidant activity in all the assayed methods, either singly taken or included in mixtures. Furthermore, the mixtures containing this supplement revealed synergistic effects in 92% of the cases. The intake of antioxidant mixtures might provide some additional benefits.