Nutriceutical potentials of Nigerian grown <i>Citrullus lanatus</i> (Watermelon) seed

Abstract

Several plants and their parts have been used both as food and as medicines since ancient times, but their safety and efficacy still need to be scientifically investigated. This study evaluated the mineral and the phytochemical composition of watermelon (Citrullus lanatus) seed-pulp and shell using standards methods of analysis. The phytochemical screening indicated the presence of alkaloids, cardiac glycoside, flavonoids, steroids, saponins and tannins in the seed-shell while alkaloids, cardiac glycoside, flavonoids, steroids and reducing sugar in the seedpulp. The mean concentrations of the minerals determined: calcium (Ca), copper (Cu), iron (Fe), potassium (K), manganese (Mn), sodium (Na), lead (Pb) and zinc (Zn) in the seed-pulp were found to be 733.4±5.02, trace, 1.85±0.07, 580.925±273, 798.15±1.84, 107.08±1.77, 5.3±0.64 and 15.625±1.24 μg/g respectively. In the seed-shell, the values were 593.13±2.65, 12.65±0.07, 14.48±2.09, 13302.273±4.56, 403.58±0.81, 174.35±1.12, 10.03±0.67and 50.575±0.60 μg/g respectively. The concentration of lead (Pb) in the seed-shell was slightly above WHO permissible limit (10 μg/g). The study revealed that watermelon seed is a rich source of both beneficial minerals and phytochemicals, which serve nutritional and medicinal purposes. It is therefore, advised that watermelon fruit be consumed along with the seed in order to fully benefit from its nutritional and medicinal values.

Keywords: Watermelon; Phytochemicals; TLC fingerprint; Minerals