Glycyl-L-valine is a dipeptide composed of glycine and valine. It is an incomplete breakdown product of protein digestion or protein catabolism.

Glycyl-l-leucine is a dipeptide that appears to be a common substrate for glycyl-leucine dipeptidase.

Aspartame is an artificial non-saccharide sweetener used as a sugar substitute in some foods and beverages. It is a methyl ester of the aspartic acid/phenylalanine dipeptide.

Glutathione acts as an antioxidant, a free radical scavenger and a detoxifying agent. It is a tripeptide comprised of three amino acids (cysteine, glutamic acid, and glycine) present in most mammalian tissue.

Bestatin is a competitive and specific inhibitor of leucine aminopeptidase, aminopeptidase B, and triamino peptidase.