Polysaccharides of Ungernia. XVII. Study of a mannan from bulbs of Ungernia oligostroma

A mannan having a linear structure and containing β-1 → 4-bound D-mannopyranose residues in the chain has been isolated from the bulbs ofUngernia oligostroma M. Pop et Vved. X-ray and electron microscope studies have been made of the mannan and its derivatives. From the x-radiographic point of view the mannan and its derivatives are amorphous. At the supermolecular level the mannan possesses an amorphous finely disperse structure with loose packing of the particles. In the acylated mannan a tendency to the formation of the characteristic laminar structure elements are observed. Such laminae may be fairly thin (down to a thickness of 0.1–0.3 µm).