Determination of D-amino acids and their distribution in mammals

D-Amino acids are the enantiomers of l-amino acids. Although the l-forms are predominantly present in life systems in the free form and also in the protein-bound form, the optically inversed D-forms were hardly found especially in higher animals. This is due to the very low amounts of these D-amino acids, and the determination is frequently disturbed by large amounts of l-amino acids and uncountable numbers of peptides and amino compounds. However, due to the recent progress in analytical technologies, several D-amino acids have been found in mammals including humans. In this chapter, the analytical methods for determining these D-amino acids and their distribution in mammals are described.