Cellulose is a polysaccharide that consists of long unbranched chain of glucose molecules (6000−10,000) linked by β , 1-4 glycosidic bond. It is structural component of cell walls of all plants, many algae and some fungi and is responsible for providing the rigidity of the cell wall. Cellulose occurs typically as microfibrils, each consisting of long parallel array of 50−60 cellulose molecules. It is the most abundant organic substance on earth.