Mannosylated derivatives of cyclodextrins (CDs), mannosyl-α, β, and γCD were synthesized from a mixture of mannose and α, β, and γCD by the reverse action of α-mannosidase from jack bean, respectively. Their structures were analyzed by FAB-MS and 13C-NMR spectroscopies, and they were identified as 6-O-α-d-mannosyl-α, β, and γCD. The optimum conditions for the production of 6-O-α-d-mannosyl-αCD by α-mannosidase were examined. Optimum pH and temperature were pH 4.5 and 60°C, respectively. Yield of mannosyl-αCD increased with increasing mannose concentration and reached more than 35% (mol/mol) at the concentration of 2 m mannose and 0.4 m αCD.
Keywords: CD; Jack bean; mannosyl-CD; reverse action; α-mannosidase.