Proteins and other nitrogenous constituents of water melon seeds (Citrullus vulgaris)

Abstract

The N of watermelon seeds is composed of: glutelin, 9.4% (extractable 1.6%, not extractable 7.8%); globulin, 73.2%; water soluble protein, 6.3%; proteoses, 3.5%; peptones, 1.1%; material precipitable by phospho-tungstic acid, 0.1%; simpler substances not precipitable by phosphotungstic acid, 1.6%. The globulin and the glutelin were isolated in pure, the former in crystalline condition and the most important amino acids in the 2 proteins determined. Independent determinations of arginine and histidine have borne out the accuracy of the values for these amino acids obtained by the N-distribution method. The seeds do not contain canavanine or citrulline, either free or combined, and only traces of free arginine.