Global Patterns of Antioxidant-Rich Food Crops Based on Geographical Origins

Abstract

We mapped antioxidant values of 118 common food crops at a global scale based on geographical origins using median oxygen radical absorbance capacity (ORAC) and total phenolics (TP) for twenty-three regions to evaluate broad-scale patterns. Using the U.S. Department of Agriculture Food Composition Database we used k-means clustering to differentiate regions based on ORAC and TP values. Latitude is positively associated with ORAC (r s = 0.51, p < 0.02) and TP (r s = 0.48, p < 0.02) with the highest values found in northeastern Europe, North America, and temperate South America. The lowest ORAC values are associated with equatorial and subtropical regions. Latitudinal differences in antioxidant properties of crops are positively associated with cold stress in the promotion of higher ORAC and TP values in colder regions. Latitudinal pattern exceptions occur in southwestern Europe where maritime conditions moderate cold stress and in the Andes where high-elevation conditions promote cold stress. Global evaluation of crop antioxidants reveals distinct geographical patterns that incorporate the long- and short-term effects of anthropogenic activity. Our findings suggest that results from smaller scale studies are operative at broader (regional-level) scales despite the influence of crop domestication and dispersal of crops across floristic boundaries.