Hongxia Wan¹, Renbin Liu², Haiyan Sun¹, Xiangying Yu¹, Yan Li¹, Yanli Cong¹, Dong Liu^1,

Determination of antioxidant activity using biologically relevant assay is important to screen vegetables for potential health benefits. This study was to evaluate the Caco-2 cell-based antioxidant activity (CAA) of 36 vegetables commonly consumed in China. Total phenolics, total flavonoids and oxygen radical absorbance capacity (ORAC) for selected vegetables were also measured to be compared with CAA values. The results showed that there was a large variation among different vegetables in CAA values with the highest value of 37 ± 3.7 µmol of quercetin equivalents (QE) / in lotus root and lowest value of 0.376 ± 0.053 µmol of QE/ in green bell pepper, and 23 vegetables were of unquantifiable CAA values due to their low activities. Correlation analysis showed that CAA values were significantly correlated to total phenolics (R = 0.516, p < 0.01) and ORAC values (R = 0.350, p < 0.05), suggesting a better predictor of total phenolics for the CAA of vegetables. The data obtained could be useful for consumers to plan antioxidant rich diets and for nutritionists to estimate health benefits of vegetables from daily intake.

vegetables, Caco-2 cell-based antioxidant activity (CAA), phenolic content, flavonoid content, oxygen radical absorbance capacity (ORAC)