Amino Acid Composition, Protein Fractions and Electrophoretic Analysis of Seed Storage Proteins in Lupins

Amino acid composition, protein fractions and electrophoretic analysis of seed storage proteins of eleven genotypes of 3 lupin species grown in Punjab area of Northwest India were analyzed. Significant genotypic variations in contents of lysine, tryptophan, sulphur containing amino acids like cysteine and methionine and storage protein fractions viz. albumin, globulin, prolamin and glutelin were observed in the seed. Electrophoretic analysis of total soluble proteins and globulin fraction from lupin seeds showed the presence of 10–15 and 8–17 bands with the molecular weight ranging from 14.6–168.2 and 11.1–109.1 kilodaltons (KDa), respectively. Furthermore, white lupins exhibited higher contents of sulphur-containing amino acids, lysine, tryptophan, crude protein, total soluble proteins and free amino acids than yellow lupins, narrow-leafed lupins and chickpea check variety “GPF2”. Higher contents of seed protein and essential amino acids in lupin species compared with chickpea check can be further used to exploit the potential of this crop in lupin breeding programme under local environment conditions.