Wiwat Wangcharoen and Wallaya Morasuk

pp. 1407 - 1415

Abstract

The antioxidant capacity of white and red holy basil leaves (Ocimum sanctum Linn., white and red varieties) from fresh markets in Chiang Mai was estimated by three different methods; ferric reducing antioxidant power (FRAP) assay, improved ABTS radical cation decolorization assay, and DPPH free radical scavenging activity; together with their total phenolic contents. Water and 95% ethanol ratios of extraction solvents were also studied, and it was found that 57 and 76% ethanol solvents were more suitable in this study. All three antioxidant capacity assays showed that red holy basil was higher in antioxidant capacity than white holy basil (p<0.05). ABTS values were higher than FRAP and DPPH values, respectively,
because of their different mechanisms, but their significant correlation (p<0.01) expressed their similar trends. In addition, correlation between results of all antioxidant capacity and total phenolic content was
found (p<0.01). ABTS values were highly correlated into the results of total phenolic content than were FRAP and DPPH values.