PROTEIN-FRACTIONS IN AMARANTH GRAIN AND THEIR CHEMICAL CHARACTERIZATION

Protein distribution in each of two selections of Amaranthus caudatus, Amaranthus hypochondriacus, and Amaranthus cruentus was established by the Landry and Moreaux fractionation scheme. Some of these fractions were analyzed for their amino acid content. Two extraction sequences were used, which differed in the first solvent, water in one and 0.5 M NaCl in the other. No differences were found in the protein fractions distribution between species or cultivars of the same species, independent of the fractionation sequence used. The solvent sequence resulted in differences in fraction I (albumin), II (globulin), III (prolamine), V (glutelin-like), and some in fraction VI (glutelins). With water as first solvent, albumins averaged 20.7, globulins 19.2, prolamines 2.2, glutelins 44.4, with 13.4% in the residue of the total protein. Albumins were rich in tryptophan, threonine, and lysine; globulins in sulfur amino acids and lysine; prolamines in threonine and leucine; and glutelins in tryptophan and leucine. © 1990, American Chemical Society. All rights reserved.