Glucose is a six-carbon monosaccharide. It is a reducing sugar. Its molecular signal. It is called aldohexose as it contains aldehyde group. Ripe fruits and honey contain high amounts of glucose. As the ripe fruit contains 12-30% glucose, it is called grape sugar. It is called dextrose, corn sugar, grape sugar, blood sugar and D-glucose. Its relative sweetness is 74. Glucose is produced in the plant body in the process of photosynthesis. However, sugars are never stored in plant bodies. It acts as the primary component of respiration.
Properties of Glucose
(i) Glucose is a simple sugar.
(ii) It is a white granular substance.
(iii) It has a sweet taste.
(iv) It is soluble in water.
(v) It is slightly soluble in alcohol, but insoluble in ether.
(vi) It contains aldehyde group. Dr. Siddique Publications
(vii) It is called aldose sugar.
(viii) It is a reactive sugar.
(ix) Glucose binds to proteins in the animal body to form glycoproteins.
(x) It reacts with phosphoric acid to form esters.
(xi) Its melting point is 146 degrees Celsius. (α- D glucose) and 150 degrees C. (β-D glucose).
Different types of glucose
(i) D Glucose (Dextrorotatory): If the hydroxyl (OH) group is attached to the right side of the 5th carbon of glucose.
It is called dextrorotatory or D glucose. Its rotation direction is to the right of the chiral center. It is a light activator. All natural glucose is D glucose. Dr. Siddique Publications
(ii) L Glucose (Laevorotatory): If the hydroxyl (OH) group is attached to the left side of the 5th carbon of glucose, it is called Laevorotatory or L glucose. Its rotation direction is to the left of the chiral center. It is a light activator. L-glucose is synthetically produced for use in diabetes medication and endoscopy. (The center along which the carbon molecules are linked is called the chiral center). Dr. Siddique Publications
(iii) α-D glucose and β-D glucose: Carbon 1 of glucose forms an oxygen bridge near carbon 5. A ring structure is formed as a result. An -OH group is generated due to the ring structure. If the -OH group is below the 1st carbon of glucose, it is called α-D glucose and if it is above the 1st carbon of glucose, it is called β-D glucose. α-glucose forms starch and β-glucose forms cellulose. D glucose is always present in the plant body.
Use of glucose
(i) Glucose is used as patient food. Quickly energizes the patient.
(ii) It is used in fruit preservation. Prevents fruit rot.
(iii) D-glucose is used to produce vitamin C from bacteria in the Richstein process.
(iv) Glucose is used in the preparation of calcium gluconate drugs.
(v) It plays a role in carbohydrate metabolism in the organism.
(vi) It is used to make citric acid, gluconic acid, bio-ethanol, sorbital etc.
(vii) It acts as a source of energy for sick people. Dr. Siddique Publications
(viii) Glycoproteins and glycolipids are formed from glucose.
(ix) Glucose is used in the process of glycolysis to generate energy.