Composition of amino acids and related nitrogenous nutrients in feedstuffs for animal diets. Academic Article uri icon


  • We analyzed the composition of amino acids (AAs) in oligopeptides, proteins, and the free pool, as well as creatine, agmatine, polyamines, carnosine, anserine, and glutathione, in animal- and plant-derived feedstuffs. Ingredients of animal origins were black soldier fly larvae meal (BSFM), chicken by-product meal, chicken visceral digest, feather meal, Menhaden fishmeal, Peruvian anchovy fishmeal, Southeast Asian fishmeal, spray-dried peptone from enzymes-treated porcine mucosal tissues, poultry by-product meal (pet-food grade), spray-dried poultry plasma, and spray-dried egg product. Ingredients of plant origins were algae spirulina meal, soybean meal, and soy protein concentrate. All animal-derived feedstuffs contained large amounts of all proteinogenic AAs (particularly glycine, proline, glutamate, leucine, lysine, and arginine) and key nonproteinogenic AAs (taurine and 4-hydroxyproline), as well as significant amounts of agmatine, polyamines, creatine, creatinine, creatine phosphate, and glutathione. These nitrogenous substances are essential to eitherDNA and protein syntheses in cells orenergy metabolism in tissues (particularly the brain and skeletal muscle). Of note, chicken by-product meal, poultry by-product meal, and spray-dried poultry plasma contained large amounts of carnosine and anserine (potent antioxidants). Compared with most of theanimal-derived feedstuffs, plant-derived feedstuffs contained muchlower contents of glycine and proline, little 4-hydroxyproline, and no creatine, creatinine, creatine phosphate, carnosine or anserine. These results indicate the unique importance of animal-source feedstuffs in improving the feed efficiency, growth and health of animals (including fish andcompanion animals). Because soy protein concentrate is consumed by infants, children and adults, as are BSFM and algae for children andadults, our findings also have important implications for human nutrition.

published proceedings

  • Amino Acids

altmetric score

  • 0.5

author list (cited authors)

  • Li, P., & Wu, G.

citation count

  • 89

complete list of authors

  • Li, Peng||Wu, Guoyao

publication date

  • April 2020