L-Phenylalanine is an essential aromatic amino acid and direct precursor to tyrosine, dopamine, norepinephrine, and epinephrine. It plays a foundational role in neurotransmitter synthesis, mood regulation, and cognitive function. As an essential amino acid, it cannot be synthesised by the body and must be obtained through diet or supplementation.
Applications:
- Cognitive health and mood support supplements
- Sports nutrition and pre-workout formulations
- Weight management (appetite regulation via CCK stimulation)
- Pharmaceutical and nutraceutical API
Key Features & Benefits:
- Essential precursor to dopamine, norepinephrine, and epinephrine
- Supports mood, focus, and cognitive performance
- No animal substance – suitable for halal and vegan formulations
- High purity white crystalline powder
- USP/Food grade available
What L-phenylalanine is
L-phenylalanine is an essential amino acid: the body cannot make it, so it comes from protein in the diet. The body converts it to tyrosine, which is the starting point for dopamine and noradrenaline. Supplement grades are white crystalline powders, usually made by fermentation. Ask for the specific optical rotation to confirm the L form, because D- and DL-phenylalanine are different products.
Phenylketonuria (PKU) labelling
People with phenylketonuria (PKU) cannot break down phenylalanine and must limit their intake. Products containing added phenylalanine, including those sweetened with aspartame, carry a phenylalanine warning in many markets. Check the labelling rules for your product before launch.
Formulation notes
L-phenylalanine is sparingly soluble in water and has a slightly bitter taste. In amino acid blends it is often combined with L-Theanine. Claims about mood, appetite or cognition are not authorised for food supplements in most markets.
What to ask for on the certificate of analysis
- Assay (%) with the method (for example titration or HPLC)
- Specific optical rotation (confirms the L form)
- Identity test (for example IR)
- Related amino acids, loss on drying and residue on ignition
- Loss on drying and heavy metals (lead, arsenic, cadmium, mercury)
- Microbiology: total plate count, yeast and mould, E. coli, Salmonella
- Batch number, manufacture and retest dates
