Taylor Ellsworth
Professor Michael Bunch
Cell Biology 112
“Effects of Amylase reaction time when breaking down starch.”
Experiment Goal: The goal of our experiment was to understand the similarities in digestion by finding out how long it takes for the amylase enzyme, found in saliva, to break down our substrate, starch.
Hypothesis: While understanding that starch is broken down by our saliva (amylase enzyme) we predict that the higher the concentration of the enzyme the faster the breakdown of the starch.
Materials: Brightly colored test tube rack, kim wipes, beaker for trash
1.5 ml microcentrifuge tubes
Test plate
Micropipetters and tips
DI water
Buffer solution … 4.5 to 8.8
I2Kl (grams iodine)
Starch solution
Enzyme (amylase)
80 degree Celsius water (HOT)
Floating test rack
Procedure: While controlling the amount of starch and the amount of buffer we use with a pH of 5.8, we want to investigate how changes in enzyme concentration affect reaction rates. First we put 500 ml of amylase from 0.2% solution (provided by Michael Bunch) into an experimental tube. We then put 3 drops of Iodine into a test plate (the color is brown). While ready to time our reaction, we added 250 ml of starch solution into the mixture of buffer and amylase. The reaction had started instantly. We first timed the reaction at 20 seconds. At 20 seconds, we removed a 25 ml sample of the mixture and dropped it into one of the test sights of iodine. The color of the brown iodine turned immediately purple. Traces of purple in the iodine and amylase mixture indicate that the amylase did not have enough time to break down the starch completely. We tried this pattern of every 20 seconds for up to three minutes. The amylase was not breaking down the starch. Because no reaction after too much time, we increased the amylase solution to 0.5% and started our experiment over.
After resetting our experiment back up