What is phenylalanine?

Answer 1

Phenylalanine is an essential alpha-amino acid. It exists in two forms, a D and an L form, which are enantiomers (mirror-image molecules) of each other. It has a benzyl side chain. Its name comes from its chemical structures consisting of a phenyl group substituted for one of the hydrogens in the side chain of alanine. Because of its phenyl group, phenylalanine is an aromatic compound. At room temperature, it is a white, powdery solid.
L-Phenylalanine (LPA) is an electrically-neutral amino acid, one of the twenty common amino acids used to biochemically form proteins, coded for by DNA. Its enantiomer, D-phenylalanine (DPA), can be synthesized artificially.

L-phenylalanine is used in living organisms, including the human body, where it is an essential amino acid. L-phenylalanine can also be converted into L-tyrosine, another one of the twenty protein-forming amino acids. L-tyrosine is converted into L-DOPA, which is further converted into dopamine, norepinephrine, and epinephrine (latter three are known as the catecholamines). D-phenylalanine can be converted only into phenylethylamine.

The genetic disorder phenylketonuria (PKU) is an inability to metabolize phenylalanine. Individuals with this disorder are known as "phenylketonurics", and must abstain from consumption of phenylalanine. It is present in many sugarless gums, Monster Munch crisps, sugarless soft drinks (such as Diet Coke) and a number of other food products, all of which must be labeled: "Phenylketonurics: Contains phenylalanine." It's important to realize that phenylalanine itself is not present in the food. Rather, the artificial sweetener aspartame (e.g. Equal, NutraSweet) is present. Aspartame is an ester that is hydrolyzed in the body to form phenylalanine, aspartic acid and methanol (wood alcohol), and it is the phenylalanine product of aspartame which then builds up in the person with PKU. The amounts produced by aspartame are an incredibly low risk factor however, as far larger quantities of the amino acid would be obtained through simply consuming any protein at all with phenylalanine content, which would include all complete proteins, as phenylalanine is an essential amino acid.

The synthesized mix DL-Phenylalanine (DLPA), which is a combination of the D- and L- forms (e.g. a racemate: a racemic compound or mixture), is used as a nutritional supplement. Research indicates that DLPA can be an effective part of an overall program to fight chronic pain and depression in some cases, including the mood swings of premenstrual syndrome (PMS). Some sources contend that DLPA can increase energy and mental alertness, as well as heighten the ability to focus in individuals with attention deficit hyperactivity disorder (ADHD).

The genetic codon for phenylalanine was the first to be discovered. Marshall W. Nirenberg discovered that, when he inserted m-RNA made up of multiple uracil repeats into E. coli, the bacterium produced a new protein, made up solely of repeated phenylalanine amino acids.

Phenylalanine uses the same active transport channel as tryptophan to cross the blood-brain barrier, and, in large quantities, interferes with the production of serotonin.

Phenylalanine is contained in most protein rich foods, but especially good sources are dairy products (curd, milk, cottage cheese), avocados, pulses and legumes (particularly peanuts and lima beans), nuts (pistachios, almonds), seeds (piyal seeds), leafy vegetables, whole grains, poultry, fish and other seafoods.

http://en.wikipedia.org/wiki/Phenylalanine

Answer 2

Phenylalanine - Used by the brain to produce dopamine and norepinephrine, chemicals that promote alertness, elevate mood, decrease pain, aid in memory and learning, and reduce hunger and appetite. Caution: Phenylalanine should not be supplemented by individuals with anxiety attacks, diabetes, pigmented melanoma (skin cancer), high blood pressure, or if pregnant.

Answer 3

http://www.anyvitamins.com/phenylalanine-info.htm

Answer 4

http://en.wikipedia.org/wiki/Phenylalanine

Answer 5

common amino acid found in many living organisms. it is good for brain

Answer 6

Not long ago I asked the question about this substance and whether there is a reason it is used in something like breath mints. I got back answers about the chemical make-up of molecules and how our bodies may produce this substance anyway - never any answers about what it has to be added to some things.

What I do know about this substance is that it shows up in some sugar-free products and even things like Listerine Breath Strips (or others like it), and it has the potential of causing kidney damage if used in large amounts. I know someone who had tests on his kidney function (and who had chewed sugar-free gum regularly) which showed an improvement after he stopped using the gum.

If nothing else, this stuff causes intestinal problems like diarrhea.

I still never got the answer as to why some sugar-free products have this stuff in them because not all sugar-free products have it. Why it must be in something like breath strips remains a mystery to me as well. I do know, though, that this stuff is potent enough so that most people who eat/drink something that has it don't need to read the label to eventually figure out the product contained. They figure out when they get the cramps a few hours later.