Preparation of L-talose and D-gulose from L-tagatose and D-sorbose, respectively, using immobilized L-rhamnose isomerase.

L-rhamnose isomerase of Pseudomonas sp. LL172 immobilized on BCW 2603 Chitopearl beads was used to produce L-talose and D-gulose. At equilibrium, the production yields of L-talose and D-gulose were determined to be 12 and 10% from L-tagatose and D-sorbose, respectively. The crystallized products were confirmed by HPLC, IR and NMR spectra, and optical rotation measurement analyses.