Characterization of a rhamnogalacturonan and a xyloglucan from neriumindicum and their activities on PC12 pheochromocytoma cells.

Two polysaccharides, a rhamnogalacturonan (J1) and a xyloglucan (J2), were isolated and purified from the whole flowers of Nerium indicum and characterized by GC, GC-MS, NMR, and ESMS. The rhamnogalacturonan was found to consist of repeating units of a linear trisaccharide with the structure [-->4)-alpha-GalpA(1-->2)alpha-Rhap(1-->4)-alpha-GalpA(1-->4)-](n)(), while the xyloglucan consisted of repeating units of the trisaccharide, which was (1-->4)-linked beta-glucopyranosyl residues as a backbone and substituted at position 6 linked to terminal alpha-xylopyranose side chains. These two polysaccharides were tested on the proliferation and differentiation on PC12 pheochromocytoma cells and found to have effects similar to nerve growth factor (NGF).