Abstract:

In this paper, first, crude water-soluble polysaccharides were extracted from Chaenomeles cathayensis using cellulase, and the optimal extraction conditions were determined via orthogonal experiments, that is, extracting the polysaccharides with a cellulose dosage of 50 U/g at 50 ℃ and pH 4.0 for 2.5 h. Next, the proteins in the crude polysaccharides were removed by means of Sevage method combined with acid-resistant proteinase. Then, the pigments in the polysaccharides were removed using macroporous resin and other small-molecule impurities were removed via dialysis. Thus, fine water-soluble Chaenomeles cathayensis polysaccharides （CCP） were obtained and further fractionated. Finally, an elution component CCP1 was separated via the column chromatography of DEAE- cellulose. According to the results of paper chromatography and Sepharose Cl-6B column chromatography, CCPI is as a kind of pure polysaccharide with a saccharide content of 97.3 % detected by the phenol-sulfuric acid assay. Moreover, as there are no absorption peaks of protein （ at 280 nm） and nucleic acid （ at 260 nm） in the UV spectrum but there are typical characteristic absorption peaks of polysaccharides in the IR spectrum, it is concluded that CCP1 is a new kind of homogeneous polysaccharide separated from Chaenomeles cathayensis.

Key words: Chaenomeles cathayensis, polysaccharide, extraction, purification, structural analysis