Cellulose is a high molecular weigh

Cellulose is a high molecular weight linear polymer of β-(1 → 4)-d-glucopyranose units in the 4C1 conformation, whereas hemicellulose is a complex mixture of various polymerized monosaccharide such as glucose, mannose, galactose, xylose, arabinose, methylglucoronic and galaturonic acids. On the other hand, lignin, found in the cell wall, is a polymeric aromatic polymer and it is a three-dimensional, highly branched, polyphenolic substance that consist of an irregular array of variously bonded “hydroxyl-” and “methoxyl-” substituted phenylpropane units. Fig. 4 portrays the textural structure of biomass, whereas Fig. 5, Fig. 6 and Fig. 7 illustrate the chemical structure of cellulose, hemicellulose and lignin, respectively.