Studies on Mannan in Wood Pulp

Part I. Isolatin of “Mannan” from β-and γ-Cellulose and their Sugar Composition

Abstract

β-Cellulose extracted from dissolving pulp with 10% aqueous sodium hydroxide, and γ-cellulose from hard sulphite pulp were fractionated into mannan, xylan and cellulose fractions according to the procedure of Hess and Liidtke.
From the results obtained it was found that the repeating fractionations caused no increase in the mannan content being more over 40% in β-mannan fraction and 50%, in γ-mannan fraction, while xylan and cellulose fractions were isolated with satisfactory results.
The purified β-mannan contained mannose, glucose and xylose at the ratio of 10:15:0.8, and the γ-mannan consisted of these sugars at the ratio of 10:9:1.
These two mannan fractions were differed from each other in the properties of their copper complex, resistances to acid hydrolysis, and degree of polymerizations.
The β-mannan was considered to consist of two parts, one of which was the degraded cellulose and the other the easily hydrolyzable γ-mannan.