Investigation on the effects of cooking methods on anti-inflammatory and antioxidant activities of five mostly consumed vegetables in winter

Abstract

The aim of this study is to investigate the effects of steaming and boiling on antioxidant and anti-inflammatory activity of five frequently consumed vegetables in winter. The vegetables were prepared by three different cooking methods including steaming, 5-minute boiling, 15-minute boiling to compare with their raw forms. Antioxidant capacity was measured with 1, 1-diphenyl–2 picrylhydrazyl (DPPH) radical scavenging method, anti-inflammatory activity was measured with 5-lipoxgenase inhibitory method, and the total phenolic content was detected after in vitro cooking process. The highest antioxidant activities among the raw vegetables were found in spinach (SR) (425.80 µg/mL, 12.83 mg/g) and broccoli (BR) (754.50 µg/mL, 7 mg/g). While boiling for 15 minutes and steaming slightly increased the antioxidant capacity in spinach and decreased it in broccoli; the highest activities among the mentioned cooking methods and vegetable samples were detected in these two vegetables. The lowest antioxidant activities were determined in leek (LR) (5662.0 µg/mL, 1.24 mg/g) and celery (CeR) (2796.0 µg/mL, 2.98 mg/g). In addition, the least affected vegetable from the cooking methods was spinach (S) (227.4-549.8 µg/mL). Cooking techniques have significative effects on the levels of phytochemical compounds and antioxidant capacities. It was observed that cooking methods increased the anti-inflammatory activity of the vegetables used in this study. Only broccoli (B) showed a decrease. The highest anti-inflammatory activity was found in the leek (L15) which was boiled for 15 minutes. Also, our results contribute to the databases that provide information about the effects of different cooking