The New International Encyclopædia/Legumin

LEGU'MIN (from Lat. legumen, bean). A vegetable proteid of the albumin group, found mainly in the seeds of many plants, including the leguminous plants, such as peas, beans, and lentils. Its exact nature is not known. Ritthausen found legumin from peas, vetches, lentils, and field beans to contain the elements in the following proportions: Carbon, 51.48 per cent.; hydrogen, 7.02 per cent.; nitrogen, 16.77 per cent.; and oxygen, 24.32 per cent. Legumin is insoluble in water, but soluble in very weak acids and alkalies, and it is not coagulated by heat. It resembles the casein of mammalian milk, with which it was considered identical by Liebig and others, and was therefore called ‘vegetable casein.’ It contains less carbon and more nitrogen, however, than true casein. Upon treatment with sulphuric acid, legumin gives leucin, tyrosin, and glutamic and aspartic acids. It is closely related to congluten, a substance found in the seeds of cereals.