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n. An essential amino acid, C4H9CH(NH2)COOH, obtained by the hydrolysis of protein by pancreatic enzymes during digestion and necessary for optimal growth in infants and children and for the maintenance of nitrogen balance in adults.

n. An essential amino acid, C6H13NO2, isomeric with isoleucine, found in most animal proteins; it is essential for growth in children.

n. a naturally occurring alpha-amino acid ((CH3)2CH.CH2.CH(NH2)-COOH), one of the building units of almost all proteins of living organisms, both animal and vegetable. It is one of the essential amino acids (not synthesized by the human body, a required component for proper nutrition), and is hydrophobic in character when bound in proteins. In isolated form it is a white, crystalline, zwitterionic substance formed, e. g. by the decomposition of proteins by pancreatic digestion, by the action of boiling dilute mineral acid, or by putrefaction. Chemically it is to be considered as amido-caproic acid. It occurs as two optical isomers, the L- and D-forms. The L-form, L-leucine, is the natural form, present in most proteins.

n. a white crystalline amino acid occurring in proteins that is essential for nutrition; obtained by the hydrolysis of most dietary proteins

"Amaranth protein, itself, is low in the amino acid leucine, which is not a serious limitation because leucine is found in excess in most common grains."

leucin   

essential amino acid   

Leu   

isoleucine    phenylalanine    valine    alanine    arginine    selenomethionine    asparagine    soln    methionine    serine/threonine