Process Biochemistry, Vol.51, No.12, 1964-1972, 2016
Strategies for eliminating (L)-arabinitol in the bioconversion of xylitol
Xylitol is a five-carbon sugar alcohol that is used in the food and pharmaceutical industries. Traditionally, xylitol is produced by the chemical hydrogenation of (D)-xylose using Raney nickel as a catalyst under high temperature and pressure. This method is not economical and is also highly polluting. As an alternative method, the bioconversion of xylitol from hemicellulose hydrolysates using microorganisms is more efficient, economical, and environmentally friendly. Unfortunately, because (L)-arabinose is the second most abundant sugar in hydrolysate and can be reduced by xylose reductase (XR), the by-product (L)-arabinitol can also be produced, thus decreasing the purity of xylitol and the efficiency of the bioconversion process. Many researchers have proposed solutions to this problem. These solutions can be divided into four categories:.(1) improving XR specificity; (2) more efficient arabinose elimination; (3) removal or conversion of (L)-arabinitol; and(4)other strategies to eliminate (L)-arabinitol. This review focuses on the most recent developments in strategies for eliminating (L)-arabinitol in the production of xylitol. (C) 2016 Elsevier Ltd. All rights reserved.
Keywords:(D)-Xylose;Xylitol production;(L)-Arabinose;(L)-Arabinitol;Hemicellulose hydrolysates;Specificity of xylose reductase