NAME: ________________________
GROUP: _______________
DATE: ________________
RATING: ________________
PHINMA UNIVERSITY OF PANGASINAN
COLLEGE OF ALLIED HEALTH SCIENCES
DEPARTMENT OF NURSING
ACTIVITY 8 - FACTORS INFLUENCING ENZYME ACTION
I. DISCUSSION:
Enzymatic Activity
Optimum Conditions
Activators and Inhibitors
II. PROCEDURE:
A. SUBSTRATE CONCENTRATION
1. Label 8 test tubes 1, 2,3,4,5,6,7 and 8 and proceed.
2. Add 1 ml. of enzyme extract to each tube.
3. Add the substrate hydrogen peroxide(H2O2) as follows:
Test tube 1= 0 drop
Test tube 2= 3 drop
Test tube 3= 6 drop
Test tube 4= 9 drop
Test tube 5= 12 drop
Test tube 6= 15 drop
Test tube 7= 18 drop
Test tube 8= 21 drop
4. Examine the bubbles and the extent it travels on the tube.
RESULT:
Test tube
1
2
3
4
5
6
Result
only a very thin layer of bubbles on the top of
the solution was formed
has almost a 1-inch layer of bubbles that
nearly looks like white foam
has a bit more than 1 inch layer of bubble or
white foam
has approximately 1.5 inches layer of bubbles
or white foam
has approximately 6.5 inches layer of bubbles
or white foam
has approximately 7.5 inches layer of bubbles
or white foam
7
8
has approximately 6.5 inches layer of bubbles
or white foam
has approximately 6 inches layer of bubbles
or white foam
CONCLUSION:
Therefore, the rate of reaction increases as the substrate concentration rises. This is
because more substrate molecules will collide with enzyme molecules, resulting in the formation
of more products. However, as the amount of substrate rises, the enzyme gets saturated with it.
As the catalytic site becomes vacant, more substrate is ready to attach and conduct reactions.
Product production is now determined by the enzyme's activity wherein the rate of the reaction
will not be influenced by the addition of more substrate.
B. ENZYME CONCENTRATION
1. Label 3 test tubes 1, 2 and 3 proceed as follows:
TEST TUBE 1= Place 1 ml enzyme
TEST TUBE 2= Place 2 ml enzyme
TEST TUBE 3= Place 3 ml enzyme
2. Add the same amount of substrate hydrogen peroxide in each test tube and observe.
3. Examine tubes.
RESULT:
TEST TUBE 1: After 20 seconds, it produces a bubble or white foam layer that was the thinnest
among the other results.
TEST TUBE 2: After 20 seconds, it produces a bubble or white foam layer that is approximately
twice the length of the bubble layer in the first one.
TEST TUBE 3: After 20 seconds, it produces a bubble or white foam layer that is approximately
thrice the length of the bubble layer in the first one.
CONCLUSION:
The relationship between enzyme concentration and enzyme activity is directly
proportional as long as the concentration of enzymes is less than the concentration of substrates.
The rate of reaction and the concentration of enzymes are proportional. In other words, adding
one enzyme increases the rate by one reaction per unit of time, while removing one enzyme
reduces the rate by one reaction per unit of time.
C. TEMPERATURE
1. A measured amount of starch solution is placed into 3 test tubes.
2. Label 3 test tubes A, B, and C that are immersed in water and kept at different temperatures.
Temperatures:
TEST TUBE A= 5 degree Celsius
TEST TUBE B= 20 degree Celsius
TEST TUBE C= 35 degree Celsius
3. The same amount of salivary amylase is placed into these test tubes.
4. The spotting tile with iodine solution will monitor the reaction.
5. After 1 minute, a drop of solution will be put in the tile. Repeat every minute.
RESULT:
TIME
TEST TUBE 1
TEST TUBE 2
TEST TUBE 3
1 MINUTE
2 MINUTES
3 MINUTES
4 MINUTES
The iodine solution
gets darker in color.
(Black)
The iodine solution
gets darker in color.
(Black)
The iodine solution
gets darker in color.
(Black)
The iodine solution
gets darker in color.
(Black)
The iodine solution
gets darker in color.
(Black)
The iodine solution
gets a little darker in
color. (Dark brown)
The iodine solution
gets darker in color.
(Black)
The iodine solution
gets very little darker
in color. (A little
lighter than dark
brown)
The iodine solution
gets darker in color.
(Black)
The iodine solution
gets a little darker in
color. (Dark brown)
The iodine solution
gets very little darker
in color. (A little
lighter than dark
brown)
The iodine solution
gets less dark in color
than the previous one.
(A little lighter than
dark brown)
CONCLUSION:
When starch is heated to the boiling point, it begins to break down, and the chains of
amyloses break, thus forming short chains of dextrin, so the color starts to change. Glucose does
not give any color in a reaction with iodine. Based on the experiment, the amylase works best at
5 degrees Celsius and worst at the high temperature of 35 degree Celsius. At 5 degrees Celsius,
all of the iodine solution efficiently reacts and changes in color but at 20 and 35 degrees Celsius
two and three iodine solutions don't completely turn into black respectively.
D. TEMPERATURE
1. Prepare 6 clean test tubes and label 1, 2, 3, 4, 5, 6. Label test tubes 1= ph 7, 2= ph 9
and 3= ph 11. Place 2ml amylase in the labelled tubes.
2. Place 1mL of starch in the other 3 tubes. Add 1 drop of iodine to each starch tube.
3. Pour 1 tube of starch solution into each amylase tube.
4. Start timer
5. Record observation at each time interval.
RESULT:
TEST
TUBES
1
WITH
pH 7
10 seconds
30 seconds
There's no
visible
change.
There's no
visible
change.
2 minutes
3 minutes 4
minutes
The top layer There is
There is
looks a little little to no little to no
white.
change in change in
the
the
5 minutes
There is
little to no
change in
the previous
result. The
previous
result.
previous
result.
2 with
pH 9
The top and
bottom are
starting to
show whitish
color.
It appears
nearly the
same as the
previous
result.
The white
color at the
bottom of the
solution is
starting to
reach the top
or appears
extending
upwards.
The white
color
from
before
becomes
whiter.
It is still
getting
whiter.
3 with
pH 11
The top and
bottom are
starting to
show whitish
color that is
more visible
compared to
test tube 2.
The solution
shows more
whiteness
than before
but there's
still black
color left.
The solution
shows more
whiteness
than before
but there's
still black
color left.
The white
color is
starting to
look
opaque.
It is still
getting
whiter.
blackest
among the
others.
It is still
getting
whiter. It is
whiter than
the result in
test tube one
and less
white than
the result in
test tube
three.
It is still
getting
whiter. It
has the
whitest
color among
the others.
CONCLUSION:
Each enzyme has a specific pH range. The activity of an enzyme is reduced when the pH
is above or below its optimum. The pH of an enzyme's optimum environment is the same as the
pH of the enzyme's natural environment. This corresponds to pH levels of approximately 7 for
several enzymes. Though, based on the experiment, the highest pH level of 11 produced the
fastest and most noticeable reaction every time interval while the lowest pH of 7 produced little
to no change at all.