The Effects on Enzymes
In this lab exercise, the study of enzyme catalase, we viewed the breakdown of hydrogen peroxide into water and oxygen. The purpose was to isolate catalase from starch and measure the rate of activity under different conditions. Changes in temperature and pH along with Substrate Concentration and Enzyme Concentration were the conditions tested in the experiment. Our class performed this experiment by breaking up into three mega-groups and the data presented in this report will reflect the data of each group. Throughout the experiment, each group encountered difficulties, which threw off the exact data that was collected. However, by working hard and forming realistic hypothesis, we were able to find the correct data.
The chemical reaction that is being studied is the hydrolysis of starch and the enzyme that is being studied is amylase. Amylase is found in the saliva. This experiment is looking at the various effects on the rate of the enzymatic hydrolysis of starch. Enzymes are biological catalysts that carry out thousands of chemical reactions that occur in living cells. Generally large proteins, enzymes are made up of several hundred amino acids. When an enzyme can no longer function at all, it is said to be denatured. There are several factors that contribute to the denaturing of the enzyme that also determine the enzyme's shape. These factors are very closely regulated in both living organisms and in laboratory environments. The temperature of the enzyme reaction or enzyme itself, as well as the enzyme’s pH, can affect the rate of activity in the function. The other factors include the Substrate Concentration and Enzyme Concentration. In this lab, we tested the enzyme reaction when adding more enzymes, the substrate, temperature, and the pH. Materials and Methods
Before the lab took place, we were given a spot/well plate, starch, amylase, iodine and water. Due to time, the class was broken up into groups to help expedite the lab. We started out by placing one drop of iodine into three separate wells of the spot/well plate. We then used a drop of starch into the first well and noted the color change. For the second well, we used a drop of amylase to mix with the iodine. For the third well, a drop of water was placed into the well and mixed with the iodine. Each well had a different color change, and each color change was recorded. The steps to complete Experiment 1, testing the effect of enzyme concentration on reaction time, was first by placing 5 ml of amylase into five test tubes. The dilution process was performed by placing 5mL of 2% Amylase into tube 1, which already contains 5mL of water, and noting the color of the mixture. Then 5mL of tube 1’s contents were placed into tube 2. This was repeated for tubes 3,4, and 5 along with the observation of color changes as each tube was diluted. However due to some problems along the way the lab results indicated that “there was no change.” With the help of our lab instructors Sam and Jing, they guided us along the way to help show the correct results which were: Tube 1 had a 1% concentration of Amylase, tube 2 had a 0.5% concentration of Amylase, tube 3 had a 0.25% concentration of Amylase, tube 4 had a 0.125% concentration of Amylase, and finally tube 5 had a 0.0625% concentration of Amylase. We then gathered more test tubes and added 1 mL of starch to each mix-test tube. Later we added one drop of iodine to each well in the spot plate and as soon as we dropped 1ml of starch, we began timing and recorded the color change. We continued the placement of one drop of the starch-amylase mixture into each well of the spot plate throughout the remainder of the experiment and each well was timed and recorded the same way. For experiment 2, we found the effect of substrate concentration on Amylase Activity. A spot plate...