Comment · Thu, August 22, 2013 · Ceretropic
What's the difference between DL-PHENYLALANINE and L-PHENYLALANINE ?
What they were answering
Sarepno · 1 points
So which one would be better for consumption ?
u/MisterYouAreSoDumb · Ceretropic
The biologically active forms of amino acids are always the levorotory enantiomers. The dextrorotory enantiomers exist in these substances because it's cheaper to synthesize a racemic version, rather than an enantiopure version. This is why you see things like L-tyrosine, L-DOPA, L-tryptophan, L-theanine, etc.
D-phenylalanine cannot be used to produce dopamine and norepinephrine, like L-phenylalanine can. However, that does not mean it's useless. D-phenylalanine has actually been shown to be analgesic, because it inhibits the degredation of enkephalin. Enkephalin is one of the body's endogenous opioids.