CELLULOSE

• It is a linear polymer of b -D-glucose.
• It is the structural polysaccharide of plant cell walls, walls of some primitive fungi, some protists, and tunic of ascidians (tunicin or animal cellulose).
• Cellulose is fibrous glucosan homopolysaccharide of high tensile strength.
• It is also the most abundant organic molecules of earth.
• Cellulose molecules are long chain polymers of 6,000 - 10,000 b -glucose units.
• They are unbranched, straight and linear. The adjacent b -glucose units are joined by b(1 → 4) linkages.
• A cotton fibre is formed of some 1500 firbils with each fibril having about 250 microfibrils.
• Cellulose microfibrils do not interfere with the permeability of the cell wall.
• Cellulose does not react with iodine solution. It is not soluble in common solvents.
• Human beings are unable to digest the same due to absence of cellulose digesting enzyme cellulase ( b - glucosidase).The enzyme is produced by very few organisams. e.g.-

                  Flagellate Trichonympha present in bodies of termites,

                  Wood rotting fungi,

                  Bacterium Rumenococcus

                      Entodinium caudatum (Ciliate) present in the rumen of ruminant animals. e.g. (Cow, Buffalo, Goat, Sheep, Deer,                             Giraffe).

• Cellulose is an important component of diet of ruminants and other herbivores. They posses symbiotic microorganisms for performing this digestion.
• Cellulose gives the bulk to human food.
• Good quality timber contains both cellulose and lignin. It is used in preparing furniture, boats, body of trucks, tools, music instruments and sports goods.
• Cellulose, the most abundant organic molecule, is the structural component of plant cell walls.
• Cellulose is used as food by herbivorous animals.
• They are helped in this activity by symbiotic microorganisms present in their alimentary canal.
• In ruminants the cellulose digesting microorganisms reside in the chambers of stomach.
• In human diet, cellulose has only roughage value.
• Microbes are used in fermentation of cellulose containing materials.
• In cotton fibres 90% cellulose is present.