In this study, the effects of three
smoke flavouring
phenols, including
4-methoxyphenol (4-MP), 4-ethyl-2-methoxyphenol (EMP), and 4-propenyl-2-methoxyphenol (
isoeugenol), on oxidative damage and
nitric oxide production, were examined. In the range 5-20μM, EMP displayed the highest inhibitory effects on radical production and biomolecule oxidation in the acellular systems of the three
smoke flavouring
phenols. In addition,
4-MP, EMP and
isoeugenol, in the range 5-20μM, protected liver cells against
tert-butyl hydroperoxide (t-BHP)-induced cytotoxicity, correlating with protection against intracellular
glutathione depletion. Meanwhile, the inhibitory effects of the three
smoke flavouring
phenols on
nitric oxide (NO) generation, in
lipopolysaccharide (LPS)-stimulated macrophages, increased with increasing concentrations. The decrease in NO production was attributed to the reduced
inducible nitric oxide synthase (iNOS) expression in macrophages. These data suggested that the three
smoke flavouring
phenols, particularly EMP, show
biological activities that contribute to antioxidation as well as anti-
inflammation.