Inhibition of induced DNA oxidative damage by beers: Correlation with the content of polyphenols and melanoidins

Title
Inhibition of induced DNA oxidative damage by beers: Correlation with the content of polyphenols and melanoidins
Publication type
Journal Article
Year of Publication
2005
Journal
Journal of Agricultural and Food Chemistry
Volume
53
Issue
9
Pagination
3637 - 3642
Date published
2005
ISBN
00218561 (ISSN)
Abstract
Beers are a source of dietary flavonoids; however, there exist differences in composition, alcohol concentration, and beneficial activities. To characterize these differences, three kinds of lager beer of habitual consumption in Spain, dark, blond, and alcohol-free, were assayed for total phenolic content, antioxidant activity, Superoxide and hydroxyl radical scavenging activities, and in vitro inhibitory effect on DNA oxidative damage. Furthermore, their melanoidin content and correlation with antioxidant activity were evaluated. Dark beer contained the highest total phenolic (489 ± 52 mg/L) and melanoidin (1.49 ± 0.02 g/L) contents with a 2-fold difference observed when compared to the alcohol-free beer. For the three kinds of beer, the antioxidant activity measured as N,N-dimethyl-p-phenylenediamine dihydrochloride concentration was strongly correlated with the total polyphenol content (R 2 = 0.91102, p < 0.005) and with the melanoidin content (R 2 = 0.7999, p < 0.05). The results support a positive effect of beers on the protection of DNA oxidative damage, by decreasing the deoxyribose degradation, DNA scission (measured by electrophoresis), and inhibition of 8-hydroxydeoxyguanosine (8-OH-dG) formation. Furthermore, a correlation between the total melanoidin content (R 2 = 0.7309, p < 0.01) and inhibition of 8-OH-dG was observed.