Antioxidant and pro-oxidant activities of n-hexane extracts from vegetables and by-products of agricultural products in bulk oils at 60 and 140°C heating

n-Hexane extract antioxidant properties from broccoli, sesame leaves, tomatos, black beans, coriander, and peels of apples, red grapes, carrots, and sweet potatos were determined in corn oil heated at 60 and 140°C. Broccoli, sesame leaves, and coriander showed high antioxidant properties. Carrots at 60°C showed prooxidative activities at both 1 and 5 mg concentrations. Red grape peels act as pro-oxidants at 1 mg, and as antioxidants at 5 mg. At 60°C, the antioxidant properties of hexane extracts were obvious, but not at 140°C. Broccoli and sesame leaves showed high anti-oxidative activities. Apple and sweet potato peels accelerated lipid oxidation rates.