We placed it in a test tube rack in order to observe the change in a prolonged period of time. We utilized the color palette (Figure 1-A) to see the change in color of the test tube. Since we used an indicator for oxygen, and guaiacol has a high likeness for oxygen, it will bind with oxygen creating a brownish color. Determining the Effect of pH on Enzymatic Activity:
This experiment dealt with the effect of pH on peroxidase. First, we made 6 pairs of test tubes. Half of them contained substrate solution and the other half contained enzyme solution. Unlike our previous experiment, this time we substituted different pH buffers for distilled water. Furthermore, for each substrate test tube we added 7mL of distilled water, 0.2 mL of guaiacol, and 0.3 mL of hydrogen peroxide for a total volume of 7.5 mL.
In the enzyme tubes, we added 6.0 mL of pH solution, beginning at pH 4 in the first tube and changing the pH to 5 on the second test tube, so on and so forth. We also added, 1.5 mL of peroxidase for a total volume of 7.5 mL. Afterwards, we mixed the solutions individually and then combined the enzyme solution to the solution of the substrate. Upon placing the tubes back on the rack, we began to time the reaction and observed the color change using the color palette (Figure