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Related to phenylalanine: Phenylalanine hydroxylase


a naturally occurring amino acid, one of the essential amino acids, necessary for optimal growth in infants and for nitrogen equilibrium in adults.

phen·yl·al·a·nine (Phe, F),

2-Amino-3-phenylpropionic acid; the l-isomer is one of the common amino acids in proteins; a nutritionally essential amino acid.


/phen·yl·al·a·nine/ (Phe) (F) (-al´ah-nēn) an aromatic essential amino acid necessary for optimal growth in infants and for nitrogen equilibrium in human adults.


(fĕn′əl-ăl′ə-nēn′, fē′nəl-)
An essential amino acid, C9H11NO2, that occurs as a constituent of many proteins and is converted to tyrosine in the body.

phenylalanine (Phe)

an essential amino acid necessary for the normal growth and development of infants and children and for normal protein metabolism throughout life. The normal value of this amino acid in serum is less than 3 mg/dL in adults and 1.2 to 3.5 mg/dL in newborns. It is abundant in milk, eggs, and other common foods. See also amino acid, phenylketonuria, protein.
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Chemical structure of phenylalanine


Alternative pharmacology
A 50:50 mixture of dextro- and levo-forms of the amino acid phenylalanine, which is present in meats and cheeses. Phenylalanine is claimed to reverse ageing by boosting the internal supply of norepinephrine, and is allegedly useful for fatigue, depression, pain and other age-related phenomena. There is no peer-reviewed scientific evidence to support its alleged effects and benefits.


One of the common amino acids in proteins; a nutritionally essential amino acid.


One of the 20 AMINO ACIDS from which proteins are constructed. Phenylalanine is an essential amino acid and cannot be synthesized in the body; it must be provided in the diet.
Phenylananineclick for a larger image
Fig. 251 Phenylananine . Molecular structure.

phenylalanine (F, Phe)

one of 20 AMINO ACIDS common in proteins, which has a NONPOLAR'R’ structure and is relatively insoluble in water.

The ISOELECTRIC POINT of phenylalanine is 5.5.see PHENYLKETONURIA.


An essential amino acid that must be obtained from food since the human body cannot manufacture it.
Mentioned in: Phenylketonuria


(F) (fen'il-al'ă-nēn)
One of the common amino acids in proteins; a nutritionally essential amino acid.

phenylalanine (fen´ilal´ənēn),

n one of the essential amino acids. See also amino acid.


a naturally occurring amino acid essential for optimal growth in young animals and for nitrogen equilibrium in adults.

phenylalanine deaminase test
a biochemical test used for the identification of enterobacteria, based on the formation of phenylpyruvic acid.
References in periodicals archive ?
Kuvan is the synthetic form of 6R-BH4, a naturally occurring co-factor that works in conjunction with the enzyme phenylalanine hydroxylase (PAH) to metabolize phenylalanine into tyrosine.
While I could find studies which showed that aspartame consumption raises phenylalanine levels, I could not find controlled human studies that proved neurological consequences.
New evidence suggests that high phenylalanine levels during just the first 2 weeks of life can affect the structural development of the visual system.
The Guthrie test measures the amount of phenylalanine in the blood.
Rationale for the German recommendations for phenylalanine level control in phenylketonuria.
If too much phenylalanine accumulates in the blood of a baby with PKU (which can happen even before birth), it can result in mental retardation.
Contract awarded for Phenylketonurics; Dairy Substitute Or Without Protein Phenylalanine
com offers 2015 Market Research Report on Global Phenylalanine Industry spread across 162 pages covering 21 company profiles.
The effects of GanedenBC30 with protein were examined in a randomized, double-blind crossover clinical trial on key amino acids, including leucine (the regulator for muscle protein synthesis), isoleucine and valine (branched chain amino acids), as well as histidine, alanine, asparagines, citrulline, cystine, glutamine (a key amino acid for supporting ph balance and the immune system), methionine, ornthinine, serine, threonine, tryptophan and phenylalanine.
PKU (phenylketonuria) - This condition means a baby cannot process a substance in food called phenylalanine.
SUGGESTED SUPPLEMENT DOSES SUPPLEMENT DOSAGE Vitamin D 5,000-6,000 IU per day Iodine 500-1,000 mcg per day DHEA 10-25 mg per day (women) / 25-50 mg per day (men) Pregnenolone 100-300 mg per day BCAA 5-20 grams per day HMB 3 grams per day Creatine 15-20 grams per day (loading phase) / 2-5 grams per day Rhodiola 200 mg per day Tyrosine 1,500-7,000 mg per da Phenylalanine 50-100 mg per day Taurine 1,500 mg-6,000 mg per day Melatonin 1-3 mg per night, 1-2 hours before sleep L-Tryptophan 250-2,500 mg at bedtime Valerian 300-600 mg, one hour before bedtime

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