Identification of bioactive peptide sequences from amaranth (amaranthus hypochondriacus) seed proteins and their potential role in the prevention of chronic diseases

Amaranth (Amaranthus hypochondriacus) is a pseudocereal with higher protein concentration than most cereal grains. Enzymatic hydrolysis and food processing could produce biopeptides from amaranth proteins; however, there is limited information about the bioactivity of peptides from amaranth proteins. The objective of this comprehensive review was to determine bioactive peptide sequences in amaranth proteins that may prevent cardiovascular disease, cancer, and diabetes. Amaranth proteins, reported in UniProt database, were evaluated for potential bioactive peptide using BIOPEP database. The 15 main proteins present in amaranth seed are 11S globulin, 7S globulin, α-amylase inhibitor, trypsin inhibitor, antimicrobial proteins, nonspecific lipid-transfer-protein-1, superoxide dismutase, ring-zinc finger protein, prosystemin, amaranth albumin 1, glucose-1-phosphate adenyltransferase, glucosyltransferase, polyamine oxidase, granule-bound starch synthase 1, and acetolactate synthase. All proteins showed high occurrence frequencies of angiotensin-converting enzyme-inhibitor peptides (A = 0.161 to 0.362), as well as of dipeptidyl peptidase IV inhibitor (A = 0.003 to 0.087). Other proteins showed antioxidative (A = 0.012 to 0.063) and glucose uptake-stimulating activity (A = 0.023 to 0.042), and also antithrombotic (A = 0.002 to 0.031) and anticancer sequences (A = 0.001 to 0.042). The results of this study support the concept that amaranth grain could be part of a "healthy" diet and thereby prevent chronic human diseases.