Pharmaceutical Grade Acetyl L-Carnitine. Antioxidant Protection For The Brain. Acetyl-L-Carnitine is a more bioavailable form of L-Carnitine an amino acid found in high concentration in human brain nerve heart liver and sperm cells. Acetyl L-Carnitine supports energy production via the metabolism of fatty acids to yield the universal energy molecule ATP. As an antioxidant Acetyl-L-Carnitine protects neurons from damage caused by superoxide radicals.