Antiradical properties of sorghum (Sorghum bicolor L. Moench) flour extracts.

In vitro antioxidative activity of solvent extracts of white sorghum flour (prepared from sorghum cv. M-35-1) were determined; fractions responsible for antiradical activity were also isolated and their activities confirmed using 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity and beta-carotene bleaching tests. Sorghum extracts were obtained in water, 60% methanol, 60% ethanol or 60% t-butanol. Radical quenching activity was highest in acetone/methanol extracts followed by methanol extracts (IC50 = 8.20 and 9.18 mug gallic acid equivalent/ml, respectively). However, total phenols content of sorghum extract fractions and their antiradical activities were poorly correlated (R2 = -1.57). Results suggest that white sorghum may be a good dietary source of antioxidant compounds with beneficial health properties.