Glucose Isomerization by Enzymes and Chemo-catalysts: Status and Current Advances

Abstract

The well-known interconversion of aldoses to their corresponding ketoses was discovered more than a century ago, but has recently attracted renewed attention due to alternative application areas. Since the pioneering discovery, much work has been directed toward improving the process of isomerization of aldoses in terms of yields, catalysts, solvents, catalytic systems, etc., by both enzymatic and chemo-catalytic approaches. Among aldose–ketose interconversion reactions, fructose production by glucose isomerization to make high-fructose corn syrup (HFCS) is an industrially important and large biocatalytic process today, and a large number of studies have been reported on the process development. In parallel, also alternative chemo-catalytic systems have emerged, as enzymatic conversion has drawbacks, though they are typically more selective and produce fructose under mild reaction conditions. Isomerization of glucose is also a central reaction for making renewable platform chemicals, such as lactic acid, ...