Peroxidase Lab Report

The Effect of Changing Substrate Amount on Peroxidase

Introduction Enzymes are proteins used in nearly all chemical reactions in organisms. These proteins are known as catalyst to speed up or enhance reactions. Enzymes are reliant on substrates; they are known to convert nearly one thousand substrate molecules per second during reactions (Freeman, 2017, 90). In reactions, there are other active conditions that can affect the enzyme. These include, but are not limited to different pH levels, changes in temperature, amount of inhibitor, and amount of salt. In the reaction done in the experiment, the enzyme is known as peroxidase and the substrate is known as hydrogen peroxide (H2O2). In every reaction, there are constants such as the buffer

The constants were the temperature, the amount of inhibitor, and pH. The equipment used includes a LabQuest Spectro Vis Plus, cuvettes, and 3 droppers containing various microliters. The experiment began by calibrating the LabQuest spectrophotometer at 500nm every 20 seconds for 120 seconds; this was to get the results on the absorbency amounts. Following that, cuvettes were filled each with 250 µl of peroxidase, 1000 µl of buffer (sodium phosphate), and 250 µl of indicator guaiacol. In each trial, there were 3 different amount of hydrogen peroxide: 250 µl, 500 µl, and 1000 µl. Before placing the hydrogen peroxide into the cuvettes, was important to have the cuvette in the spectrophotometer, ready to hit the 'record data' button as the reaction happened to quickly. For each hydrogen peroxide amount, there were 3 trials ran to gather plenty of data to find an average and reduce outliers. After all, 9 trials, the experiment was complete leaving only to average the absorbency for each substrate amount by adding the absorbencies per trial (3 per µl amount) and dividing by

To answer this, it was found that it does which can be seen in Table 1 and Figure 1. The easiest way to answer the question was to seamlessly conduct the overall experiment with several amounts of substrate. Doing so, it was found there it a relationship between the amount of a substrate and its effect on the absorbency of an enzyme. The hypothesis that increasing the amount of substrate decreases the absorbency was supported by the results. There was a negative correlation between the amount of hydrogen peroxide added and the absorbency of the