Antioxidant Capacity and Total Phenol Content of Commonly Consumed Indigenous Foods of Asian Tropical Regions

Abstract

In order to screen the antioxidant capacity of commonly consumed indigenous foods of tropical region, vegetables, fruits, tea, oil seeds, legumes, spices and cereal were analyzed. Among the vegetables, green chili showed the highest total oxygen radical absorbance capacity (ORAC(subscript FL)) and lipophilic ORAC (L-ORAC(subscript FL)); whereas, bean showed highest hydrophilic ORAC (H-ORAC(subscript FL)) content. The H-ORAC(subscript FL) of vegetable samples varied between 2.26 to 23.08 μmol of Trolox equivalent (TE)/g of fresh weight (FW) and L-ORAC(subscript FL) content widely varied from 0.20 (sweet pumpkin) to 16.95 (green chili). The range of H-ORACFL values of fruits showed large variation (0.45-178 μmol of TE/g FW). All four different types of tea showed high H-ORAC(subscript FL) (1,295.84-2,709.11 μmol of TE/g), in contrast to negligible amount of L-ORAC(subscript FL). In legumes, H-ORAC(subscript FL) content ranged from 16.22 to 140.54; whereas, L-ORAC(subscript FL) ranged from 4.43 to 25.78. Porso millets showed higher L-ORAC(subscript FL) value (19.4) as compared to H-ORAC(subscript FL) (0.8). In case of spices, L-ORAC(subscript FL) content varied from 29.75 ± 0.00 to 1,575.24 ± 39.63, which is considerably higher as compared to H-ORAC(subscript FL) (61.68 ± 1.71 to 272.82 ± 1.05) content. Comparatively, spices showed much higher H-ORAC(subscript FL) values as compared to fruits analyzed. In case of selective vegetables, fruits and tea samples, the total phenol content was highly correlated with the H-ORAC(subscript FL) content.