Levodopa is an immediate precursor of dopamine and product of tyrosine hydroxylase. It derived from vanillin is widely used for treatment of Parkinson’s disease.

Astragaloside A are bioactive saponins isolated from dried roots of plants of the genus Astragalus, which is used in traditional Chinese medicine.

Trypsin is a digestive enzyme found in the digestive system. The enzyme catalyzes the hydrolysis of peptide bonds breaking down proteins into smaller peptides.

Pepsin is an enzyme that is secreted in the digestive track of mammals. It works to break down proteins into smaller peptides which can readily be absorbed by the small intestine.

Alpha-GPC has been used to rescue choline auxotrophy. It has also been used for the synthesis of glycerophospholipids.