D-Phenylalaninyl-D-Phenylalanine-D5
Parent: Phenylalanine
Levodopa EP Impurity B
Parent: Levodopa / Phenylalanine
N-Nitroso-N-methyl-DL-phenylalanine
Parent: Phenylalanine
Phenylalanyl-Tryptophane-D5 (Mixture of Diastereomers)
Parent: Phenylalanine
Phenylalanine and Related Compound
Commercial and pharmaceutical specifications vary by grade but typical high purity L phenylalanine is specified at assay ≥98.5% w w. Individual related substances such as D phenylalanine, phenylpyruvic acid and phenylacetic acid are commonly limited to ≤0.2 to 0.5% w w each, with total related impurities generally not to exceed 1.0% w w. Typical limits and analytical controls include enantiomeric impurity D phenylalanine ≤0.5% w w, phenylpyruvic acid ≤0.3% w w, residual moisture ≤0.5 to 1.0% w w, heavy metals ≤10 ppm and microbiological limits appropriate to the grade. Residual solvents and volatile impurities are controlled to ICH recommended limits and are monitored by GC or GC MS, metallic contaminants by ICP MS, and organic related substances by validated HPLC methods. Exact impurity limits depend on intended use food, feed or pharmaceutical and on the applicable pharmacopeial or regulatory standard.
FAQ
Phenylalanine is used as a nutritional essential amino acid in protein synthesis, as an intermediate in metabolic pathways leading to tyrosine and catecholamine neurotransmitters, as an ingredient in animal feed and dietary supplements, and industrially as a starting material for synthetic chemistry and for the production of the artificial sweetener aspartame.
Phenylalanine itself is not an additive in cola; however the artificial sweetener aspartame, which is present in some diet cola formulations, contains a phenylalanine residue. When aspartame is metabolized it releases a small amount of phenylalanine, which is why products sweetened with aspartame carry an advisory for individuals with phenylketonuria.
The warning relates to phenylketonuria PKU, a genetic disorder in which affected individuals lack functional phenylalanine hydroxylase and cannot metabolize phenylalanine to tyrosine. Elevated phenylalanine levels can cause serious neurodevelopmental damage in untreated people with PKU, therefore foods and products that release phenylalanine include warnings to protect that population.
No, Phenylalanine is not classified or used as a laxative. At very high doses some amino acids can cause gastrointestinal discomfort, but phenylalanine does not have recognized laxative properties and is used nutritionally rather than as a gastrointestinal stimulant.