Non-Cellulosic Glucan

The hypocotyl tissue from which the P-glucan was obtained contains both primary and secondary cell walls. Thus, it is not known whether such glucans exist in primary cell walls of dicots. If such a glucan does exist in primary cell walls, the glucan would be difficult to classify. The glucan does not appear to be associated with galacturonosyl 

Cellulose is the most abundant polysaccharide in nature and is probably the most studied cell wall polymer. Most of the structural studies of cellulose have been carried out with material from secondary cell walls little data is available for primary cell wall cellulose. The chemistry of cellulose has been reviewed numerous times (56, 78, 107), The present review considers only the major aspects of cellulose structure and assumes that the cellulose of primary walls is similar to that of secondary walls. 

It may be that the glucan chains of cellulose have no natural ends, that is, once a chain is initiated, it never ends except when a fiber is physically separated from its synthetic enzymes. This idea is supported by the electron microscopic observation that the cellulose fibers do not appear to have natural termination points. It may also be that 

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