Influence of Cooking Methods on Antioxidant Activities of Selected Leafy Vegetables , , and in Sri Lanka.

Green leafy vegetables (GLVs) are abundant in bioactive compounds and constitute a crucial part of a balanced diet. Sri Lankan green leafy vegetables which are edible and available for consumption have not been thoroughly investigated, whilst their consumption can deflate the risk of arising several degenerative diseases, such as cancer and cardiovascular diseases. The present study was aimed at evaluating the antioxidant capacities of the leafy vegetables, (Kurignan), (Aguna), and (Girithilla), with different thermal treatments (70°C, 120°C, and 170°C) which are used in domestic cooking processes. Heat treatments significantly affect the antioxidant capacity and polyphenolic content of most vegetables analyzed, either increasing or decreasing the concentration of these compounds. In the presence of thermal treatments, (14.52-20.28 mg GAE/g DW) and (19.75-27.13 mg GAE/g DW) showed a significantly higher ( < 0.05) total phenolic content. The temperature treatment did not alter the ABTS radical scavenging activity in . In contrast, an increment of ferric reducing antioxidant power (41.26-54.85 mg TE/g DW) and DPPH radical scavenging activity (0.11-0.26 mg TE/g DW) was observed. treated at 170°C appeared to have a significantly higher amount (104.93 ± 1.41 mg TE/g DW) of ferric reducing antioxidant power compared to its raw form. All cooking processes with their corresponding thermal treatments caused a significantly lower ( < 0) amount of antioxidant capacity in