Best Conditions for Amylase to Digest Starch
Introduction:
In this experiment I am trying to find the best conditions for amylase
to digest starch. I am going to vary the PH from PH6 to PH9 to see
which one digests starch the fastest. This will show which PH enzymes
will work best in. I will put 3cm³ of amylase, 1cm³ of starch and 1cm³
of buffer to each test tube. I will heat them in a water bath to 40º.
I will then every 2 minutes test the solution for starch using iodine.
Prediction:
I predict that amylase will digest fastest at PH7 because it is the
same PH as inside your mouth wear enzymes would be digested.
Equipment:
Test Tubes
Test Tube Rack
Stop Watch
Thermometer
Pipette
Starch
Amylase
Buffer-PH6, PH7, PH8, PH9
Dimple Tray
Preliminary Tests:
I will use these tests to see whether I need to change my amounts of
starch, amylase and buffer or the times when I measure the solution.
[IMAGE]
Time(mins) Is Starch Present
1 Yes
2 Yes
3 Yes
4 Yes
5 Yes
6 Yes
7 Yes
[IMAGE] 8 Yes
9 Yes
10 Yes
11 No
The experiment was taking too long so we changed the time when we
measured the solution to 2 minutes rather than 1.
Test:
We first tested PH6:
[IMAGE]
Time(mins) Is Starch Present
[IMAGE]
2 Yes
4 Yes
6 Yes
8 Yes
10 Yes
12 Yes
14 Yes
16 Yes
18 Yes
20 Yes
22 Yes
24 Yes
26 Yes
28 Yes
30 Yes
32 No
PH6 took 32 minutes to digest the starch.
PH7:
[IMAGE]
Time(mins) Is Starch Present
We used the pipette filler and filled the glucose rinsed pipette to add 10ml of 10% of glucose in test tube 0.
way. I will put each piece of potato into the 5 test tubes and add the
Test tube A will have a piece of potato which is this size. Test tube
6. Place the test tube in the beaker. Secure the test tube and thermometer to the retort stand using clamps. Begin heating the water bath gently.
The temperature of amylase The temperature of starch Room temperature Concentration Ph values The variable I will be changing is the volume of amylase. Safety: The sand is To make sure I carry out this experiment safely I will make sure I wear a pair of goggles. I will ensure I keep my stool under the table and all
Five test tubes - To hold the potato and each one of the five sugar solutions individually;
* Make sure each test tube is exactly the same size, I will do this by
an unknown amino acid. A titration curve is the plot of the pH versus the volume
I am going to use a range of concentrations to enable me to get a good
If I was to do this experiment again I might use a Fungi amylase to
The Effect of pH on the Activity of Catalase Planning Experimental Work Secondary Resources Catalase is a type of enzyme found in different types of foods such as potatoes, apples and livers. It speeds up the disintegration of hydrogen peroxide into water because of the molecule of hydrogen peroxide (H2O2) but it remains unchanged at the end of the reaction.
It is essential for the stomach to realease the gastrin hormone so to maintain an acidity of 1.5-2 pH. Although this high acidity doesn't digest the chyme, it has many functions. The highly acidic environment kills most of the microorganisms ingested with food. It also denatures proteins and inactivates the enzymes presented in food. It is essential for activating pepsin so to do its proper function in breaking proteins, and to break plant cell wall ingested in food and the connective tissues in meat. (2)
Some improvements to the experiment might be using Na Acetate or Na Citrate as buffers instead of KHPO4. The pH ranges are 4.5-5.5 and 4.7-5.5, respectively. This range falls closer to the ideal pH of 5, then KHPO4 (pH
and a fall in temperature will slow them down. In many cases a rise in
tube. Add 6 mL of 0.1M HCl to the first test tube, then 0.1M KMnO4 and