Antioxidant action of fermented grain food supplement: Scavenging of peroxyl radicals and inhibition of plasma lipid oxidation induced by multiple oxidants

- Antioxidant effect of fermented grain food supplement was assessed in plasma solution.
- Rate and amount of scavenging peroxyl radical were measured separately.
- Inhibition of plasma lipid oxidation by biologically relevant oxidants was assessed.
- Lipid oxidation by peroxyl radical, hypochlorite, and singlet oxygen were suppressed.
- This method may be useful for screening antioxidant capacity of foods and supplement.

Unregulated oxidative modification of biological molecules induced by multiple oxidants in vivo has been implicated in the pathogenesis of various diseases. Accordingly, the role of antioxidants contained in foods in the maintenance of health and prevention of diseases has received much attention. The efficacy of antioxidants against oxidative stress depends on the nature of oxidants. In the present study, the antioxidant action of fermented grain food supplement, Antioxidant Biofactor (AOB), for scavenging peroxyl radical and inhibition of plasma lipid oxidation induced by multiple oxidants was measured. The antioxidant efficacy against lipid oxidation was assessed by the level of lipid hydroperoxides produced using diphenyl-1-pyrenylphosphine, which is not fluorescent per se but reacts with lipid hydroperoxides stoichiometrically to yield highly fluorescent diphenyl-1-pyrenylphosphine oxide. AOB acted as a potent peroxyl radical scavenger and suppressed lipid oxidation induced by peroxyl radical, peroxynitrite, hypochlorite, and singlet oxygen, but not by 15-lipoxygenase.