L-Carnitine

Thus far in Biochemistry, some new knowledge that I have connected with past knowledge is about the ammonium compound carnitine, which is biosynthesized from the amino acids lysine and methionine. Before learning about Carnitine in biochemistry, my only knowledge about it was from having seen it marketed as a workout supplement by itself, most often labeled as L-Carnitine.

In living cells, Carnitine is required for the transport of fatty acids from the cytosol into the mitochondria during the breakdown of lipids for the generation of metabolic energy. The reason that I have most often seen it labeled as L-Carnitine is because, as we learned in class, many amino acids (and other products of metabolism) have two forms that are mirror images of each other and are considered the L and D forms of the substance, based on chemical structure. the L form is the biologically active form of Carnitine, whereas the D-form is the enantiomer and is not a marketed product because it is biologically inactive.

Even if you are not considered an athlete, there is medical evidence that suggests that the body's production of carnitine slows just with age. As a result, many nutritionists have begun suggesting that their older clients increase dietary sources of carnitine, which are mainly derived from the muscle, kidney, and liver content of animal products but some plant sources can also be found in avocado, alfafa, and wheat germ.