L carnitine is primarily synthesized in the liver from the amino acids lysine and methionine through a series of four enzymatic reactions, with the liver and kidneys converting the precursor butyrobetaine into active Carnitines as Mitochondrial Modulators of Oocyte and Embryo Bioenergetics Long chain fatty acid activation, entry into mitochondria and Download Scientific Diagram Fatty acid transport into mitochondria by carnitine transporter