Carnitine

Carnitine (β-hydroxy-γ-N-trimethylaminobutyric acid, 3-hydroxy-4-N,N,N-trimethylaminobutyrate) is a quaternary ammonium compound involved in metabolism in most mammals, plants and some bacteria. Carnitine may exist in two isomers, labeled D-carnitine and L-carnitine, as they are optically active. At room temperature, pure carnitine is a white powder, and a water-soluble zwitterion with low toxicity. Carnitine only exists in animals as the L-enantiomer, and D-carnitine is toxic because it inhibits the activity of L-carnitine. Carnitine, derived from an amino acid, is found in nearly all organisms and animal tissue. Carnitine is the generic expression for a number of compounds that include L-carnitine, acetyl-L-carnitine, and propionyl-L-carnitine. It is most accumulated in cardiac and skeletal muscles as it accounts for 0.1% of its dry matter. It was first derived from meat extracts in 1905, therefore the name carnitine is derived from Latin ``carnus'' or flesh. The body synthesizes enough carnitine from lysine side chains to keep up with the needs of energy production in the body as carnitine acts as a transporter of long-chain fatty acids into the mitochondria to be oxidized and produce energy. Some individuals with genetic or medical disorders (like preterm infants) cannot make enough, so this makes carnitine a conditionally essential nutrient for them.

Question: is carnitine the same as l-carnitine
Answer: no