Biotechnological Synthesis and Transformation of Valuable Sugars in the Food and Pharmaceutical Industry

Oligosaccharides and glycoconjugates find application in the food, feed, cosmetic and pharmaceutical industry, which makes glycosylation the target for development of new therapeutic agents, functional food ingredients and other valuable molecules. Unlike other biological molecules, the synthesis of carbohydrates is not template dependent, such that the design of a vast catalog of multifunctional glycostructures is potentially possible. The challenge to achieve regio- and stereo selective structures has made the carbohydrate chemistry one of the most defiant fields of study over the last century, since the synthesis of such a complex molecules is difficult and often impossible to achieve by solely a traditional chemical approach. Enzymatic synthesis however, generally leads to structurally controlled products and overcomes structural complexity. Hence, enzymatic and chemo-enzymatic processes continue gaining attention through the years. Although nature supplies a pool of enzymes able to efficiently catalyze a number of reactions, there are still many transformations requiring redesign at molecular level. Different approaches for the synthesis of valuable glycostructures are covered in this review and their scope and limitations for industrial application are discussed.