Record Information
Creation date2010-04-08 22:06:27 UTC
Update date2020-09-17 15:30:54 UTC
Primary IDFDB004940
Secondary Accession NumbersNot Available
Chemical Information
FooDB NameL-(-)-Phenylalanine
DescriptionPhenylalanine, abbreviated Phe or F, is a neutral, nonpolar, hydrophobic, essential amino acid. It is the precursor of the amino acid tyrosine, a precursor of the skin pigment melanin and a precursor of catecholamines that include tyramine, dopamine, epinephrine, and norepinephrine. Catecholamines are neurotransmitters that act as adrenalin-like substances. Interestingly, several psychotropic drugs (mescaline, morphine, codeine, and papaverine) also have phenylalanine as a constituent. Phenylalanine is highly concentrated in the human brain and plasma and is found naturally in mammalian breast milk. Normal metabolism of phenylalanine requires biopterin, iron, niacin, vitamin B6, copper, and vitamin C. An average adult ingests 5 g of phenylalanine per day and may optimally need up to 8 g daily. Phenylalanine is highly concentrated in several high protein foods, such as meat, cottage cheese, and wheat germ. An additional dietary source of phenylalanine is artificial sweeteners containing aspartame. Generally, aspartame should be avoided by phenylketonurics and pregnant women. When present in sufficiently high levels, phenylalanine can act as a neurotoxin and a metabotoxin. A neurotoxin is a compound that disrupts or attacks neural cells and neural tissue. A metabotoxin is an endogenously produced metabolite that causes adverse health effects at chronically high levels. Chronically high levels of phenylalanine are associated with at least five inborn errors of metabolism, including Hartnup disorder, hyperphenylalaninemia due to guanosine triphosphate cyclohydrolase deficiency, phenylketonuria (PKU), tyrosinemia type 2 (or Richner-Hanhart syndrome), and tyrosinemia type III (TYRO3). Phenylalanine also has some potential benefits. Phenylalanine can act as an analgesic, providing relief for premenstrual syndrome and may enhance the effects of acupuncture and electric transcutaneous nerve stimulation (TENS) for Parkinson's patients. Phenylalanine and tyrosine, like L-DOPA, produce a catecholamine-like effect. Phenylalanine is better absorbed than tyrosine and may cause fewer headaches. Low phenylalanine diets have been prescribed for certain cancers with mixed results. For some tumours that use more phenylalanine than others (such as melatonin-producing tumours called melanomas) may benefit from low phenylalanine diets.
CAS Number63-91-2
Predicted PropertiesNot Available
Chemical FormulaC9H11NO2
IUPAC name
InChI IdentifierInChI=1S/C9H11NO2/c10-8(9(11)12)6-7-4-2-1-3-5-7/h1-5,8H,6,10H2,(H,11,12)/t8-/m0/s1
Isomeric SMILESN[C@@H](CC1=CC=CC=C1)C(O)=O
Average Molecular Weight165.1891
Monoisotopic Molecular Weight165.078978601
ClassificationNot classified
Physiological effect

Health effect:


Route of exposure:


Biological location:


Indirect biological role:

Industrial application:

Biological role:

  • Dairy products
  • Eggs
  • Meats
  • Grains:

    Nuts and legumes:

    Physico-Chemical Properties - Experimental
    Physico-Chemical Properties - Experimental
    Physical stateNot Available
    Physical DescriptionNot Available
    Mass CompositionNot Available
    Melting PointNot Available
    Boiling PointNot Available
    Experimental Water SolubilityNot Available
    Experimental logPNot Available
    Experimental pKaNot Available
    Isoelectric pointNot Available
    ChargeNot Available
    Optical RotationNot Available
    Spectroscopic UV DataNot Available
    DensityNot Available
    Refractive IndexNot Available
    EI-MS/GC-MSNot Available
    MS/MSNot Available
    NMRNot Available
    ChemSpider IDNot Available
    ChEMBL IDNot Available
    KEGG Compound IDNot Available
    Pubchem Compound IDNot Available
    Pubchem Substance IDNot Available
    ChEBI IDNot Available
    Phenol-Explorer IDNot Available
    DrugBank IDNot Available
    HMDB IDNot Available
    CRC / DFC (Dictionary of Food Compounds) IDNot Available
    EAFUS IDNot Available
    BIGG IDNot Available
    KNApSAcK IDNot Available
    HET IDNot Available
    Food Biomarker OntologyNot Available
    VMH IDNot Available
    Flavornet IDNot Available
    GoodScent IDNot Available
    SuperScent IDNot Available
    Wikipedia IDNot Available
    Phenol-Explorer Metabolite IDNot Available
    Duplicate IDSNot Available
    Old DFC IDSNot Available
    Associated Foods
    FoodContent Range AverageReference
    Biological Effects and Interactions
    Health Effects / BioactivitiesNot Available
    EnzymesNot Available
    PathwaysNot Available
    MetabolismNot Available
    BiosynthesisNot Available
    Organoleptic Properties
    FlavoursNot Available
    MSDSNot Available
    Synthesis ReferenceNot Available
    General ReferenceNot Available
    Content Reference— Duke, James. 'Dr. Duke's Phytochemical and Ethnobotanical Databases. United States Department of Agriculture.' Agricultural Research Service, Accessed April 27 (2004).