Malonic acid (propanedioic acid) is the archetypal example of a competitive inhibitor: it acts against succinate dehydrogenase (complex II) in the respiratory electron transport chain. Malonic acid is found to be associated with malonyl-CoA decarboxylase deficiency which is an inborn error of metabolism.

3, 4-Dihydroxyphenylethanol is an active ingredient extracted from the olive.

Osteocalcin (7-19) (human) is a peptide fragment of Osteocalcin, can be used as a peptide tag.