[Correlation Between Functional Groups and Radical Scavenging Activities of Acidic Polysaccharides from Dendrobium].

Objective: To compare the radical scavenging activity of five different acidic polysaccharides, and to find the correlation with the functional groups.

Methods: Alkali extraction method and Stepwise ethanol precipitation method were used to extract and concentrate the five Dendrobium polysaccharides, and to determine the contents of sulfuric acid and uronic acid of each kind of acidic polysaccharides, and the scavenging activity to ABTS+ radical and hydroxyl radical. Functional group structures were examined by FTIR Spectrometer.

In vitro antioxidant activities of a water-soluble polysaccharide derived from Dendrobium nobile Lindl. extracts.

A water-soluble polysaccharide (DNP), isolated from the aqueous extracts of the stem of Dendrobium nobile Lindl., was found to have an average molecular weight (Mw) of about 8.76 x 10(4)Da.