Abstract:

Sargassum hemiphyllum polysaccharides (SHP) was extracted from dry Sargassum hemiphyllum
(Turner) C.Ag. powder using 60-80 ℃ purified water and then hydrolyzed with 4.0 g/L trifluoroacetic
acid at 80 ℃. Without any derivatization reaction, the determination of monosaccharides in SHP was
developed by anion-exchange chromatography with pulsed amperometric detection with an Au working
electrode and an Ag/AgCl reference electrode. Monosaccharides were separated on a CarboPacTM PA10
anion-column (2 mm i.d.×250 mm) by using isocratic elution consisting of 14 mmol/L sodium
hydroxide at a flow rate of 0.20 mL/min. Six monosaccharides, xylose, galactose, arabinose, glucose,
rhamnose and fructose, contained in SHP were separated and determined. Their contents in SHP were
2200, 820, 98, 4560, 358 and 740 mg/kg, respectively. The recoveries of the six monosaccharides were
in the range 86.0%-108.0%. The detection limits for these monosaccharides ranged from 5.6 to 89.6 μ
g/kg. The experimental results showed that SHP mainly consisted of xylose and glucose with smaller
quantities of galactose, arabinose, rhamnose and fructose. This method is suitable for the
determination of monosaccharides without any derivatization reaction at the level of μg/kg in dry
algae with high sensitivity and good precision.

Key words:
polysaccharides, monosaccharide, pulsed amperometric detection, Sargassum hemiphyllum (Turner) C.Ag. , ion chromatography （IC）