Habitat: Cultivated throughout India on sandy river beds, up to an altitude of 1,500 m.
English: Watermelon.Ayurvedic: Kalinga.Unani: Tarbuz.Siddha: Poiychaviral, Tharbuza- palam (Tamil.Action: Pulp—cooling and refreshing, a rich source of pectin, carotenoids, surcose (as major sugar). Fruit juice is prescribed in strangury and urinary complaints, also in hepatic congestion and intestinal catarrh. Seeds—cooling, purgative, diuretic, demulcent (used in urinary infections). Leaves— febrifuge. The pericarp is given in diarrhoea.
Watermelon juice contains citrullin (0.17%) and arginine, which are thought to increase urea production in the liver, thus increasing the flow of urine.The seeds possess a high lipase activity comparable to that of wheat germ, in addition to high lipoxygenase, urease and trypsin-inhibitor activities. Aqueous extract of the seeds also exhibit amylase inhibitor activity. The seed oil is used as a substitute for almond oil.The roots of mature plant contain a triterpene, bryonolic acid. Bryono- lic acid possesses a stronger antiallergic activity with lesser side effects than that of glycyrrhetinic acid, the aglycone of glycyrrhizin, used clinically in Japan for the treatment of allergy and hepatitis.