Cellulose is a complex homopolysaccharide. The cell wall of autophagous plants is composed of cellulose. Cellulose is the most abundant organic material on Earth. Glucose is obtained by wet analysis of cellulose with hydrochloric acid or sulfuric acid or sodium hydroxide. Cellulose molecules contain β-1-4 glycosidic linkages. Neither animals nor humans can digest cellulose because they have no enzymes to break these β-1-4 glycosidic bonds. French chemist Anselme Payen (1838) discovered cellulose. Kobayashi & Shoda (1992) first produced synthetic cellulose. Dr. Siddiq Publications
Amount of cellulose
94% in cotton, 90% in linen or linseed, 90% in cellulose, 30-40% in grass, 60% in wood, 45% in dry hemp fiber, 58% in jute, 40% in sugarcane bagasse, 42% in wheat straw and 40-70% in organic soil. remains
Properties of Cellulose
(i) Cellulose is a tasteless, odorless and colorless substance.
(ii) It is chemically inert, but converts to glucose on wet analysis with strong acids.
(iii) It is insoluble in water and organic solvents. Dr. Siddique Publications
(iv) Its molecular weight ranges from 2 lakh to several lakh daltons.
(v) It is non-toxic and non-oxidizing.
(vi) It shows no color in iodine solution.
(vii) It is tough and fibrous.
(viii) It has no nutritional value.
(ix) Cellulose contains 44.41% carbon, 44.4% oxygen and 6.2% hydrogen.
Chemical structure of cellulose
Cellulose is a complex polysaccharide. It is composed of glucose molecules. Numerous glucose molecules are linked by β 1-4 glycosidic bonds to form cellulose. Cellulose is converted to glucose by hydrolysis with H2SO4 or HCl or NaOH.
Uses of cellulose
(i) Textile industry: Cellulose is used as the main raw material for textile industry. Rayon is made from cellulose as the raw material of the fabric.
(ii) As an explosive: It is used as a nitrate explosive. Cellulose is used as raw material for making nitrocellulose. Dr. Siddique Publications
(iii) For making furniture: Cellulose is the main material of wood and bamboo. Various types of furniture are made from bamboo and wood.
(iv) In paper industry: It is used to make filter paper and tissue paper. Cellulose insulators are made from newsprint paper in a recycling process. Cellulose insulator is an environmentally friendly coating.
(v) Digestion: Wood-boring insects use cellulose to digest wood.
(vi) In making gum: Methyl cellulose is used in making gum. Pure cellulose is mixed with water to make glue.
(vii) For making photographic film: It is used for making photographic, cellophane and celluloid.
(viii) In Biotechnology: Cellulose produced from fungi and bacteria is being used in biotechnology.
(ix) As Structural Material: Cellulose acts as the main structural material of plants. It forms leaves, stems and branches of plants. Dr. Siddiq Publications
(x) Skeletal system of plants: Cellulose provides strength and protection to plants. Cellulose is therefore called the skeletal system of plants.
(xi) Faecal formation: Most of the cellulose ingested with animal feed is excreted as faeces. Rafez relieves constipation. Cellulose is therefore essential for animal life. Dr. Siddiq Publications
(xii) Stationary phase: Cellulose is used as the stationary phase in thin layer chromatography.
Why can’t people digest cellulose?
Cellulase, the enzyme that digests cellulose, is not produced in the mammalian digestive system. However, a type of mitotic bacteria lives in the digestive system of cows, buffaloes, goats, deer, sheep etc. All these bacteria produce cellulose digesting enzyme cellulase. This enzyme aids in cellulose digestion by cleaving the β, 1-4 glycosidic bonds of cellulose. Humans cannot digest cellulose because the human digestive system lacks such mitotic bacteria. But the human diet must contain cellulose-type food. Because cellulose is essential for the production of stool. Dr. Siddiq Publications