L-Phenylalanine
L-Phenylalanine is one of the nine essential amino acids and the precursor of the amino acid L-Tyrosine.
L-Phenylalanine occurs naturally in many protein-rich foods such as milk, eggs and meat. It plays an important role in the biosynthesis of other amino acids and is converted to L-Tyrosine in the body to then be used in the biosynthesis of dopamine and norepinephrine neurotransmitters.