Comparison between alkali-soluble and water-soluble polysaccharides from Dendrobium officinale

Objective To establish the HPLC characteristic spectra of water-soluble and alkali-soluble polysaccharides from D. officinale and analyze the difference of the monosaccharide composition and bioactivity. Methods The PMP-HPLC fingerprints of both polysaccharides were established,then the difference of their spectra,monosaccharide composition and similarity were analyzed. The WST-1 method was used to evaluate the anti-tumor activity of polysaccharides. The antioxidant activity of polysaccharides were evaluated according to the ability of clearing · OH and H2O2. Results The water-soluble polysaccharides were mainly composed of D-mannose and D-glucose,while alkali-soluble polysaccharides contained D-mannose,galacturonic acid,D-glucose,D-galactose and D-xylose. The bioactivity studies demonstrated that both alkali-soluble and water-soluble polysaccharides could inhibit the proliferation of Hela cells. However,the antioxidant activities of alkali-soluble polysaccharides were more significant than the water-soluble polysaccharides. Conclusion There are differences between alkali-soluble and watersoluble polysaccharides on the characteristic spectra and activities,which may be caused by the different monosaccharides compositions.