Enzymes are biological catalysts that speed up the rate of chemical reactions by lowering the reactants’ activation energy. The goal of this lab was conducted to determine the optimal temperature for bacterial and fungal Amylases and evaluate how temperature affects the catabolic rate of enzymes. Enzyme reaction rate was measured using an Iodine test in which drops of starch solution with either fungal or bacterial Amylase exposed to different temperatures were mixed with Iodine. Iodine is a dark blue color in the presence of starch and turns light yellow in its absence. Bacterial Amylase had an optimal temperature of 55°C, meaning that starch was broken down the fastest at this temperature. Fungal Amylase showed a slightly lower optimal temperature of 40°C. Bacterial and fungal Amylase at lower temperatures had a slower reaction rate because starch and Amylase molecules moved slower. The reaction rate of both enzymes decreasing after 55°C could be due because the enzymes may have begun to denature, losing its potency to break down starch. In order for each …show more content…
The lowest reaction rate of fungal amylase was at 0°C which is accounted by the slow movement of molecules that decreases enzyme and substrate collision. The difference in optimal temperature between the fungal and bacterial amylase may be due to the different environments that each enzyme is naturally found in. Bacillus licheniformis is found in a wider range of environments so its enzymes have to survive a higher range of temperatures. Where as Aspergillus oryzae is found in lower temperature habitats preventing its enzymes from tolerating a wider range of temperatures (Hideki, 1982). At 75°-85 °C no starch was hydrolyzed because the fungal enzyme denatured. If both bacterial and fungal enzymes were allowed to react with starch for a longer period all of the starch solution would have been