This experiment consist of 2 part . First part is to test whether solution A and solution B are reducing sugar. Second part of the experiment is to investigate 2 type of reaction , biological reaction and chemical reaction. The chemical enzyme is hydrochloric acid while the biological enzyme is amylase saliva . The specific enzyme reaction involved in the experiment is hydrolysis reaction. Solution B is a polysaccharide which will break down into monosaccharide by hydrolysis reaction.
Hydrochloric acid is a very strong acid and it can digest any that contact with it. At high temperature, hydrochloric acid can act as chemical enzyme which can hydrolyses polysaccharide. Hydrochloric acid can break down solution B and starch which are polysaccharide to their respective monosaccharide. Temperatures may have affect the substances such as solutions A and B, saliva, and hydrochloric acid. Saliva is a type of biological enzyme needs an optimum temperature of 37°C to carry out high activity.
High temperature causes amylase to become denatured, and the shape of the active site changes, because the bonds in the enzymes are broken because of the heat energy gained to brak the bond. When an enzyme is denatured, it cannot function, hence , no catalyse biological reaction. When solution B is under high temperature, solution B gains heat, which is converted to kinetic energy. Solution B thus have high kinetic energy, and its easier to be catalyzed because the activation energy is achieved easily. Because it has high kinetic energy, the solution can be catalyzed by the hydrochloric acid.
The product that formed after hydrolysed is broken to monosaccharide which are glucose molecules. This is because glucose is a type of reducing sugar that can turns Benedict’s solution from blue to brick-red precipitate. Starch and glucose are consider as carbohydrate . Figure below shows the structures of starch.
Structure of glucose is shown as above .
Basis of the test used in this experiment is for amylase enzyme and hydrochloric acid to function as enzymes to convert starch, which is solution B to their monomers. At 37°C, amylase enzyme are able to convert starch to glucose because it is in their optimum temperature. Beside that, HCl cannot carry out reaction because its has not gained enough energy to catalyse reaction. At 95°C, HCl are able to catalyse starch into glucose molecule because it has gained enough energy through heating process. However, amylase enzyme are denatured at high temperature. High temperature breaks the bonds that holds the 3D shape of an amylase enzyme. This causes the active site of the amylase enzyme to be altered, and therefore starch molecules cannot bind to the altered active site. The purpose of adding sodium hydroxide is to neutralize the hydrochloric acid in the solutions, while adding Benedict’s solution is to test the presence of glucose molecules.
Carbohydrate Solution B is the complex molecule and this is because show no reaction in benedict’s test. Before hydrochloric acid is added, solution B still is starch. After hydrolyzing reaction take place , is shows positive result to th benedict’s test. Means glucose is present in solution B after hydrolyzing. Conclusion : Salivary amylase will only hydrolyse starch into glucose at optimum temperature(37 while hydrochloric acid can hydrolyse starch at temperature (c).