Amylase Lab Report PDF

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Lab Report on Amylase...

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Susanna Conigliaro Biology 2312 Lab Report Title: Effects of Amylase on Starch Breakdown Introduction Amylase is an enzyme who's primary function is to break down starch into simpler sugars. In the lab an experiment was performed to determine the effect of amylase in different situations. To determine the effect of amylase tests using iodine and Benedict's test were used. The Benedict’s test uses Benedict’s reagent which is used to detect the presence of simple carbohydrates ( “Organic Molecules,” n.d.). The Benedicts’s test is a qualitative test since it detects the presence of simple carbohydrates with a change in color. The iodine test is another qualitative test which changes from an orange to a dark blue color when in the presence of starch. The iodine changes colors since it adheres to amylose molecules and reflects back a dark color (Byrid-McDevitt, 2016). The two tests are great indicators to test the effect of amylase. Amylase is an enzyme which breaks down starch into simple sugars. Digestion is the process of breaking down food through the use of mechanical and chemical processes. Amylase is an enzyme which is naturally found in saliva and is responsible for the chemical digestion that occurs in the mouth. When someone eats a piece of bread the salivary amylase in the mouth coats the bread and starts to break down the carbohydrate into simpler sugars. In the lab amylase was used in different tests to show the effectiveness of the enzyme.

Objective: The objective for the lab is to examine the effect of amylase on starch.

Methods and Materials To carry out the experiment materials the necessary materials were collected and organized. First a beaker of water was set to boil, and while waiting six tubes were collected and labeled to carry out six different tests. In test tube #1 6 gtts of amylase and water were added. In test tube #2 6 gtts of starch and water were added. In test tube #3 6 gtts of maltose and water were added. In test tube #4 6 gtts of amylase was added and then out to boil for four minutes before adding 6 gtts of starch. In test tube #5 6 gtts of amylase and starch were added. In test tube #6 6 gtts of amylase and starch were added. Once the test tubes were set up, the tubes were then transferred to their proper incubating places. Test tubes #1- #5 were placed in an incubator at 37 degrees Celsius while test tube #6 was placed in an ice tub for 20 minutes. After the time elapsed a pipette was used to transfer a sample from each tube onto paper to perform the iodine test. Each sample was labeled to avoid confusion and then a drop of iodine was added to each. The results from the test were then recorded. The test tubes were then used to perform the Benedict’s reagent test. A drop of Benedict’s reagent was added to each test tube and then placed in boiling water for 5 minutes. After 5 minutes the tubes were removed from the water and the data was collected regarding the change in each test tube’s color.

Table 1: Results from Benedict’s Test and Iodine Test Additives (6 Tube 1: gtt ea) Amylase & Water

Tube 2: Starch & Water

Tube 3: Maltose & Water

Tube 4: Boiled Amylase & Starch

Tube 5: Amylase & Starch

Tube 6: Amylase & Starch

37’C

37’C

37’C

37’C

37’C

0’C

yellow

black/blue

yellow

black/blue

yellow

yellow

Result: (+) or (-)

-

+

-

+

-

-

Benedict’s test (color change)

yellow

blue

orange

yellow

yellow

yellow

Result: (+) or (-)

+

-

+

+

+

+

Incubation condition IKI test (color change)

Results

In the data collected the effect of amylase can be observed in using two different tests and six different situations. Test tube #1 contained amylase and water which had negative results for both the Iodine and Benedict’s tests. Test tube #2 contained starch and water which was positive for the Iodine test, but negative for Benedict’s test. Test tube #3 contained maltose and water which was negative for Iodine test, but positive for Benedict’s test. Test tube #4 contained boiled amylase and starch which was positive for both Iodine and Benedict’s tests. Test tube #5 contained amylase and starch which was positive for Iodine test, but positive for Benedict’s test.Test tube #6 has the same additives as test tube #5, but this test was done at 0 degrees Celsius. Test tube #6 was negative for Iodine test, and positive for Benedict’s test.

Picture 1. The picture to the left shows the different solution that were used for the tests.

Picture 2. Pictured to the left is the Iodine and Benedict’s reagent which was used to perform the two tests.

Picture 3. The picture to the left shows the results for the Iodine test. According to the results test tubes #2 and #4 are positive for the presence of starch while test tubes # 1,3, 5, and 6 are negative.

Picture 4. The picture to the left shows the test tubes prior to being boiled for the Benedict’s reagents test.

Picture 5. The picture to the left shows the results of the Bendict’s reagents which shows that test tube #2 is negative and test tubes #1, 3, 4, 5, and 6 are positive for the presence of simple carbohydrates.

Discussion The six different tests results help to explain the effect of amylase on its substrate. Test tube #1 was a control test for the iodine test since it did not contain the substrate so no starch was present. However, looking at the results there may have been an issue with the test since the Benedict’s test was positive. This could be a result from human error in which the sample placed for the test could have been from a mistake and taken from test tube #5. Test tube #2 acted as a

control for the Benedict test since the tube contained only simple sugars so it is not possible to have carbohydrates when the only thing present is starch in the sample. Test tube #3 contained maltose which is a carbohydrate which explains why the Benedict’s test was positive since amylase broke down the carbohydrate. Test tube #4 was used to show the effect of boiled amylase. Since amylase is an enzyme it is sensitive to heat. The results show that amylase was unable to break down the starch in the test tube. Test tube #5 was negative for starch since amylase was able to break down the starch, and positive for Benedict’s test since the starch was broken down. The first five test tubes were incubated at 37 degrees Celsius while the last one was incubated at 0 degrees Celsius. Test tube #6 therefore tested the effect of temperature on the enzyme. In this test the amylase was still able to break down the starch in the test tube so the iodine test was negative and the Benedict’s test was positive since the starch was broken down.

Conclusion When performing these tests it is important to understand the effect of amylase and the contents of each tube. Since amylase is an enzyme it is important to understand how each test is used to determine the ability of amylase to break down starch. If amylase and starch is present then in the end product amylase will break down the starch so no starch will be detected resulting in a negative Iodine test. However, if amylase is present and no substrate then both tests should be negative. If no amylase is present and starch is in the test tube the Iodine test will be positive since there is no enzyme to break down the substrate. In the test that were done the ability for amylase to break down starch worked at both 37 degrees Celsius and 0 degrees Celsius.

References Byrid-McDevitt, L. (2016, September 23). Saturday Science: Incredible Iodine. Retrieved November 24, 2018, from https://www.childrensmuseum.org/blog/saturday-scienceincredible-iodine

Organic Molecules. (n.d.). Retrieved November 24, 2018, from https://www.nku.edu/ ~whitsonma/Bio150LSite/Lab 3 Organic/Bio150LRevMolec.html...