Isolichenin is isolated in an improved yield from Iceland moss by a modification of the method of Chanda, Hirst, and Manners, whose report that isolichenin is constituted solely of glucose units united by 1,4- and 1,3-linkages is confirmed by the method of partial acid hydrolysis. It is further shown that these linkages have the α-configuration inasmuch as maltose and nigerose are components of the partial hydrolysate. There is some lack of regularity in the distribution of the α-1,3- and α-1,4-links in isolichenin although the detection of nigerotriose and maltotriose in the trisaccharide fraction of the acid hydrolysate shows that both types of linkage can occur at least in pairs. No evidence is forthcoming that branching occurs in isolichenin. It is further established that isolichenin is not identical with nigeran, in which there is an alternation of α-1,4- and α-1,3-links. Nevertheless the ratio of 1,3- to 1,4-links (55:45) in isolichenin is not far removed from that in nigeran (approx. 50:50).
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