Abstract: Polysaccharides were extracted from dried powder of Citus reticulata peel with acidic water, followed by pigment removal on D-201 ion exchange resin, protein removal by Sevag,s method, dialysis and freeze-drying. The CPA-I fraction was achieved by sequential column chromatographies on DEAE-sepharose fast flow and Sephadex G-100. Monosaccharide composition analysis of CPA-I was carried out by HPLC based on pre-column derivatization with 1-phenyl-3-methy1-5-pyrazolone (PMP). High performance size exclusion chromatography (HPSEC) was used for purity analysis and relative molecular weight determination. UV-visible and infrared (IR) spectral analyses were conducted for structural characterization. The results showed that the molecular weight of CPA-I with high purity was 7.96×104, and the monosaccharide composition of the polysaccharide was composed of galacturonic acid and arabinose. The IR spectrum indicated that CPA-I was a galacturonic acid polysaccharide esterified by carboxylic acid.

Key words: Citus reticulata peel, polysaccharide, isolation and purification, monosaccharide composition