Abstract:

The crude polysaccharide (MCP) extracted from the fruits of Momordica charantial was subjected to DEAE-cellulose column chromatographic separation and Sephadex G-100 column chromatographic fractionation and a polysaccharide fraction with a high ability to scavenge superoxide anion and hydroxyl free radicals, named MCP Ia, was obtained. According to UV spectroscopic analysis and cellulose acetate membrane electrophoresis, MCP Ia was a single composition. Its monosaccharide composition was determined by HPLC to consist of L-rhamnose, D-xylose, D-fructose and D-galactose, in a molar ratio of 4.4:2.3:1:5.7, with the possibility of containing glucose. The IR spectral analysis showed that there were intramolecular hydrogen bond and intermolecular hydrogen bond in MCP Ia. In addition, the existences of stretching vibration of the carbon-hydrogen and deformation vibration of hydroxyl group and characteristic absorption of ribofuranoside were also demonstrated. Therefore, MCP Ia is a typical polysaccharide.

Key words: Momordica charantial polysaccharides, purification, infrared spectrum