Soluble sugar and polyols were determined by an Agilent
1200 HPLC system (Agilent Technologies, Palo Alto, CA) equipped
with an Alltech 3300 evaporative light scattering detector
(ELSD) (Alltech Associates, Deerfield, IL). The assay was performed
on a Sugar-D column (4.6 mm 250 mm, 5 lm; Nacalai Tesque
Inc. Kyoto, Japan) and the mobile phase was composed of
acetonitrile (LC grade) and deionised water (75:25 (v/v) with
injection volume of 20 lL at a flow rate of 0.9 mL/min. The
ELSD was operated at 35 C, and nitrogen was used as the
nebulising gas.