Antioxidant activity and phenolic content of roots, tubers and vegetables commonly consumed in India

Epidemiological evidence suggests that consumption of vegetables can prevent degenerative diseases caused by oxidative stress. Considering scanty data available on antioxidant activity (AOA) of roots, tubers and vegetables commonly consumed in India, the objective of the present study was to assess their AOA and relate it to their total phenolic content. AOA was assessed in vegetables (n = 19) and roots/tubers (n = 10) by DPPH (2,2′-diphenyl-1-picryl hydrazyl) scavenging activity and FRAP (ferric reducing antioxidant power) methods and the total phenolic content (TPC) using Folin–Ciocalteu reagent. Although AOA as well as TPC showed wide variation among roots, tubers and vegetables studied. AOA (both DPPH and FRAP) was significantly correlated with TPC among all the foods studied, with the correlation coefficient (r) values being 0.76 and 0.85 (p < 0.01) respectively with FRAP and DPPH activity among roots and tubers while among the vegetables studied, the corresponding values were 0.85 and 0.79 (p < 0.01) respectively. The results suggest that phenolic compounds may be significant contributors to the AOA of the vegetables, roots and tubers studied.