phenylalanine

American  

[fen-l-al-uh-neen, -nin, feen-] / ˌfɛn lˈæl əˌnin, -nɪn, ˌfin- /

noun

Biochemistry.

1. a crystalline, water-soluble, essential amino acid, C 6 H 5 CH 2 CH(NH2 )COOH, necessary to the nutrition of humans and most animals, obtained chiefly from egg white or skim milk. Phe; F

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phenylalanine British  

/ ˌfiːnaɪlˈæləˌniːn, ˌfɛnɪl- /

noun

1. an aromatic essential amino acid; a component of proteins

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phenylalanine Scientific  

/ fĕn′əl-ăl′ə-nēn′ /

1. An essential amino acid. Chemical formula: C ₉ H ₁₁ NO ₂ .

2. See more at amino acid

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Etymology

Origin of phenylalanine

First recorded in 1880–85; phenyl + alanine

Example Sentences

See Examples For:

phenylalanine

Phenylpropionate and hippuric acid are produced when bacteria process phenylalanine, and they are associated with gut health and healthy body weight.

From Science Daily ● Aug. 15, 2026

The paper, titled "The role of phenylalanine and tyrosine in longevity: a cohort and Mendelian randomization study," examined whether levels of these nutrients in the blood are connected to lifespan.

From Science Daily ● Feb. 26, 2026

People with PKU cannot break down phenylalanine, an amino acid found in protein foods.

From BBC ● Jan. 1, 2024

However, for individuals with a rare genetic disorder called phenylketonuria, phenylalanine can accumulate and cause health issues, so they are sometimes instructed to avoid it.

From Salon ● Jul. 14, 2023

The WHO reports show that aspartame itself is rapidly broken down in the gut into three other substances - phenylalanine, aspartic acid and methanol.

From BBC ● Jul. 13, 2023