Separation and Structural Characterization of Tri-Glucosyl-Stevioside

Abstract

Stevioside is a non-cariogenic and low-calorigenic diterpenoid glycoside has slightly bitterness and bad after taste. Enzymatic modification by alternansucrase from Leuconostoc citreum SK24.002 was utilized in biotransformation of stevioside to remove the bitter taste fully or partially and an aftertaste of the stevioside, using sucrose as donor and stevioside as acceptor. Tri-glucosyl-stevioside produced during alternansucrase acceptor reaction of stevioside were successfully separated using adsorption separation technology of macroporous adsorption resin (AB-8) flowed by semipreparative high performance liquid chromatography. Structure of the product was characterized to be 13-{[α-D-glucopyranosyl-(1→3)-α-D-glucopyranosyl-(1→6)-α-D-glucopyranosyl-(1→3)-β-Dglucopyranosyl-( 1→2)-β-D-glucopyranosyl]oxy}kaur-16-en-19-oic acid β-D glucopyranosyl ester on the basis of extensive one dimension and two dimensional NMR and LC-ESI-MS in negative mode data.