Betaine is a zwitterionic quaternary ammonium compound and is mainly present in animals, microorganisms and plants. It is one of the main constituent of several food items like wheat, shellfish, spinach and sugar beets. It is also termed as trimethylglycine, lycine, glycine betaine and oxyneurine. Betaine is a methyl derivative of glycine. It has a molecular mass of 117.2.
End-product of oxidative metabolism of choline, betaine is a general methyl donor, in particular in a minor pathway of methionine biosynthesis. It is used to treat homocystinuria, which is a defect in the major pathway of methionine biosynthesis.
Betaine, as an osmolyte helps to guard the cells, proteins and enzymes from environmental stress. It also acts as a methyl donor to involve in the methionine cycle.