Abstract: To explore the content and the monosaccharide composition of the polysaccharide in Rosa laevigata Mickx and provide references for the quality control and the pharmaceutical utilization of R.laevigata,the total polysaccharide was obtained by water extraction and alcohol precipitation method.The polysaccharide content was detected by anthrone sulfuric acid colorimetry using the glucose calibration.Then the monosaccharide compositions of the polysaccharide were analyzed by TMS pre-column GC-MS method.The results showed that the yield of total polysaccharide was 29.38%.The polysaccharide was composed by arabinose,rhamnose,xylose,mannose,galactose,glucose,galacturonic acid and fructose,and the contents of glucose,mannose,fructose and galactose were reached to 65.03%,7.36%,16.11% and 8.87%,respectively,obviously higher than the other 4 monosaccharides in R.laevigata polysaccharide.

Key words: Rosa laevigata, polysaccharide, extraction, purification, monosaccharide, GC-MS