Chapter 16 - Challenges and prospects of xylitol production by conventional and non-conventional yeasts

Abstract

Xylitol, sugar alcohol, is widely used in the confectionary, pharmaceutical, and nutraceutical fields due to its ability to prevent diseases and as a low-calorie sugar substitute for people suffering from diabetes. At an industrial level, xylitol is currently produced by catalytic hydrogenation of pure xylose. However, biotechnological xylitol production is a more popular and sustainable alternative as the process conditions are economically feasible and less extensive. Many wild-type microorganisms are known to produce xylitol. Of these, yeasts are regarded as the best xylitol producers. Many strategies involving metabolic engineering of conventional as well as nonconventional yeasts have been developed, which have improved xylitol titer and productivity as compared to the wild-type strains. This chapter briefly reviews the current and alternative routes of xylitol production, highlighting the diversity of yeasts used and the challenges of such alternative production methods.