ABSTRACT
The important structural requirements for the observed immunomodulating activities seem to be branched structures involving arabinogalactan regions and an rhamnogalacturonan (RG) backbone. The presence of immunomodulating polysaccharides in Malian medicinal plants can be related to the medical effects. However, the putative immunomodulatory applications of the pectic polysaccharides studied here will need further investigation. P. Albersheim et al. have suggested that the same set of pectic subunits is present in the cell walls of all higher plants. These subunits include homogalacturonan, RG-I and substituted galacturonans like RG-II and xylogalacturonan. Compounds that are capable of interacting with the immune system to upregulate or downregulate specific parts of the host response can be classified as immunomodulators. Polysaccharides showing immunomodulating activities are exhibited in a wide range of glycans, extending from homopolymers to highly complex heteropolymers. The polysaccharide-rich fractions both from the bark and the leaves were tested in a rodent model for anti-ulcer activity.
