Inhibition of Helicobacter pylori hemagglutination by polysaccharide fractions from roots of Panax ginseng

Polysaccharides from the roots of Panax ginseng were extracted by hot water and fractionated by using ethanol precipitation and ion exchange chromatog raphy. Fractions FC (crude extract), F1 (fraction precipitated by ethanol), F1N (fraction unbound to DEAE-Sepharose CL-6B), and F1A (bound fraction) w ere obtained. Their carbohydrate analyses showed that acidic fraction F1A c ontains higher amounts of galactose, arabinose and uronic acids, in compari son to FC and F1. Fraction F1N mainly consists of glucose. The inhibition o f Helicobacter pylori-induced hemagglutination revealed different inhibitor y activities of these fractions. In particular, acidic fraction F1A showed a remarkable inhibitory activity (minimum inhibition concentration was 0.25 mg/ml) among the polysacharide fractions. However, digestion of the fracti on F1A with pectinase resulted in a lower molecular weight oligosaccharide fraction F1AP which was non-inhibitory at the concentration of 4 mg/ml. Com parison of inhibitory activities and carbohydrate compositions of isolated fractions indicates that the activity correlated with the contents of galac tose, arabinose, and uronic acids. These data suggest that acidic polysacch arides may be responsible for the inhibitory activity.