Also found in: Medical, Wikipedia.


A change in the optical rotation of light that takes place in the solutions of freshly prepared sugars.



a gradual change in the optical activity of freshly prepared solutions of monosaccharides and some other optically active compounds. Mutarotation is a result of the inter-conversion of tautomeric forms of monosaccharides, leading to the establishment of a dynamic equilibrium between the forms. Thus, upon completion of mutarotation a solution of glucose has a specific rotation ]p20 of +52.5° and consists of 37 percent α-glucose with [α]p20 of +112° and 63 percent β-glucose with [a]p20 of +18.7°.

The rate of mutarotation depends on the temperature and nature of the solvent; it increases in the presence of acids and bases and particularly in the presence of bifunctional acid-base catalysts such as 2-oxypyridine. In living organisms, the mutarotation of monosaccharides and disaccharides is catalyzed by the enzyme aldose 1-epimerase.


Khimiia uglevodov. Moscow, 1967.
Mentioned in ?
References in periodicals archive ?
Glucose undergoes mutarotation between its different anomers.
Isbell, A Note on the Purification of [alpha]-d-Xylose and its Mutarotation, Research Paper 723, J.
2] investigated the mutarotation of [alpha]-D-glucose to [beta]-D-glucose and observed a 3-fold reaction rate enhancement.