After pretreatment the materials were separated by filtration in a Büchner funnel: the alkali-soluble (mostly lignin and alkali-soluble polysaccharides) and the alkali-insoluble (mostly cellulosic fibers) fractions. The fibers were washed with water until neutral pH and drained in a Büchner funnel to the lowest water retention level. These materials were stored in vacuum-sealed plastic bags at 4 C with a moisture content around 70 wt%. Both glucans and lignin recoveries in the alkali-treated materials were obtained according to the following equation: