Methods for Extraction and Purification of Lignin and Cellulose from Plant Tissues

Abstract

Isolation of the two most abundant plant macromolecules, lignin and cellulose, from the plant tissues is reviewed. Isolation methods depend on the plant tissue that is used as the source of the polymers. Assessment of purity has an important place in the whole isolation process. Extent of needed purity depends on the further application of the obtained polymers. Different lignin extraction procedures are presented. Lignin isolation via preceding extraction of pulp is usually applied on wood as a starting material. The procedure preceded by cell wall extraction and combined with lignin complexation with thioglicolic acid is used for plant tissues containing various kinds of cells or low lignin content comparing with protein content. Lignin purifi cation with ionic liquids, as well as those obtaining Brauns' native lignin, kraft lignin, or lignosulfonate are also described. The review of cellulose isolation procedures is presented, such as the alkaline procedure, as well as the method using ultrasound treatment, or the method applying enzyme technology. Dilute acid pretreatment in cellulose isolation is also depicted.