tryptophan

An essential amino acid, C₁₁H₁₂N₂O₂, formed from proteins during digestion by the action of proteolytic enzymes. It is necessary for normal growth and development and is the precursor of several substances, including serotonin and niacin.

Same as proteinochromogen.

An essential amino acid having an indole side chain; it is present in many foods, especially chocolate, oats, bananas and milk; it is essential for normal growth and development and is the precursor of serotonin and niacin; any specific form of this compound, or any derivative of it.

an amino acid that occurs in proteins; is essential for growth and normal metabolism; a precursor of niacin