Abstract

Fruits are indispensable in today’s world owing their tremendous health benefits. Cucumber and watermelon are commonly consumed fruits worldwide. In this study, antioxidant potential of crude methanol extract of different concentrations of cucumber and watermelon were screened for antioxidant activity using total phenolic content, ferric reducing power (FRAP), ferric thiocyanate (FTC) tests and free radical scavenging (DPPH) assay. They are good source of calcium, magnesium and copper with appreciable amounts of vitamin C (143.360 ± 101.400 mg/100 g) for cucumber and vitamin A (90.980 ± 22.860 mg/100g; 29.475 ± 0.575 mg/100 g) for both watermelon and cucumber respectively. It was found that polyphenolics compounds were maximum in watermelon (87.04 ± 0.55 mg/g GAE in concentration 100 mg/mL). The extracts showed a potent DPPH free radical scavenging activity; cucumber had maximum percentage inhibition at 20 µg/mL concentration (29.2%) compared to watermelon at 40 µg/mL concentration (13.5%). These fruits also exhibited fairly good antioxidant activity with in both FRAP (0.517 mg/100 g; 0.317 mg/100 g) and FTC (17.2%; 31%) methods for watermelon and cucumber respectively.

Keywords: Cucumber, Watermelon, Antioxidants activities