In-Vitro Antioxidant Activity of Lycopene Extracted from Citrulluslanatus (WATER MELON) and Lycopersiconesculentum Mill (TOMATOES)

Abstract

Lycopene makes up the majority of carotenoids in watermelon and tomatoes. Carotenoids are antioxidants responsible for preventing human diseases including cardiovascular diseases, cancer, and other chronic diseases. Lycopene was extracted using n-hexane and acetone from two species of watermelon (dark green and light green skin) and tomatoes (beefsteak and plum). The concentrations were determined using UV-Vis Spectrophotometer at 480 and 503 nm wavelength. The ferric reducing antioxidant power (FRAP) and 2, 2 –Diphenyl -1- Picrylhydrazyl (DPPH) free-radical scavenging activity of the extracted lycopene samples were also assessed. There were variations in the lycopene content in each of the tomato and watermelon species analysed. The average concentration of lycopene extracted from tomatoes and watermelon were 301 and 155.22 μg/g respectively. The average percentage inhibition activity for FRAP was 67.3 % for tomatoes and 61.75 % for watermelon while for DPPH, the average percentage inhibition activity were 62 and 58 % for tomatoes and watermelon respectively. The tomatoes samples had the highest lycopene content and the highest percentage inhibition activity compared to watermelon, however, Vitamin C (standard antioxidant) percentage inhibition activity was 90 %. The study revealed that the lycopene extracted from watermelon and tomato had an in-vitro antioxidant activity which is, however, lower than that of vitamin C. Lycopene in tomatoes and watermelon can, therefore, be used as a medicinal and functional food to manage diseases caused by free radicals and reactive oxygen species.