Enzyme Activity

Only available on StudyMode
  • Download(s): 1858
  • Published: September 9, 2011
Read full document
Text Preview
LABORATORY REPORT
(Click on the Save a Copy button on the panel above to save your report)

Activity: Name: Instructor: Date:

Enzyme Activity Pam Campbell Id 0002337 Dr. Murphy Nmezi August 9, 2011

Predictions
1. Sucrase will have the greatest activity at pH 6 2. Sucrase will have the greatest activity at 40 °C (104 °F) 3. Sucrase activity increases with increasing sucrose concentration until a plateau is reached.

Materials and Methods
Effect of pH on Enzyme Activity. 1. Dependent Variable. amount of product (glucose and fructose) produced 2. Independent Variable. pH 3. Controlled Variables. temperature; amount of substrate (sucrose) present; sucrase + sucrose incubation time

Effect of Temperature on Enzyme Activity. 1. Dependent Variable. amount of product (glucose and fructose) produced 2. Independent Variable. temperature 3. Controlled Variables. pH; amount of substrate (sucrose) present; sucrase + sucrose incubation time

Effect of Substrate Concentration on Enzyme Activity. 1. Dependent Variable. amount of product (glucose and fructose) produced 2. Independent Variable. amount of substrate (sucrose) present 3. Controlled Variables. temperature; pH; sucrase + sucrose incubation time 1. Describe what is measured as an indicator of sucrase activity and why this is an indicator of sucrase activity. Glucose is measured as an indicator of sucrase activity, as glucose is a producut produce by sucrase activity. 2. Explain why denatured sucrase was used as a control. Denatured sucrase was used as a control to determine if a true effect was made on the active sucrase by pH, temperature, and sucrose, or if affect would be seen in both the denatured and active sucrase.

3. Alkaline DNS denatures sucrase. Explain why it is important to denature the enzyme. It is important to determine if pH, temperature, and sucrose do have a true effect on active sucrase.

Results Table 1: Effect of pH on Sucrase Activity
1 2 3 average ph 3 0.171 0.159 0.166 0.165 ph 4 0.309 0.319 0.302 0.31 ph 5 0.646 0.658 0.652 0.652 Optical Density ph 6 0.964 0.925 0.964 0.951 ph 7 0.762 0.775 0.778 0.772 ph 8 0.401 0.43 0.435 0.422 ph 9 0.176 0.15 0.173 0.166

Effect of pH on Sucrase Activity

1. State the optimum pH for sucrase activity and how sucrase activity changes at more acidic and alkaline pH values. The optimum pH for sucrase activity is 6 and decrease with greater acidic and alkalline values.

Table 2: Effect of Temperature on Sucrase Activity
10 °C (50 °F) 0.006 0.006 0.007 0.006 20 °C (68 °F) 0.251 0.285 0.273 0.27 30 °C (86 °F) 0.767 0.789 0.799 0.785 Optical Density 40 °C 50 °C (104 °F) (122 °F) 0.969 0.93 0.947 0.922 0.945 0.947 0.954 0.933 60 °C (140 °F) 0.843 0.827 0.829 0.833 70 °C (158 °F) 0.641 0.623 0.632 0.632

1 2 3 average

Effect of Temperature on Sucrase Activity

2. State the optimum temperature for sucrase activity and how sucrase activity changes at lower and higher temperatures. The optimum temperature for sucrase activity is 40 degrees Celcius. Sucrase activity decrease at greater or lower temperature and may become denatured.

Table 3: Effect of Sucrose Concentration on Sucrase Activity 1 2 3 average 35 g/L 0.988 1.001 0.987 0.992 30 g/L 0.983 0.977 1.012 0.991 25 g/L 0.946 0.94 0.943 0.943 Optical Density 20 g/L 15 g/L 0.93 0.861 0.922 0.86 0.908 0.848 0.92 0.856 10 g/L 0.779 0.759 0.774 0.771 5 g/L 0.513 0.523 0.506 0.514 0 g/L 0.003 0.002 0.002 0.002

Effect of Sucrose Concentration on Sucrase Activity

3. State how sucrase activity changes with increasing sucrose concentration. Sucrase activity increase with increasing sucrose concentration until it reaches a level of plateau at 30 g/L.

Discussion
1. Explain how pH and temperature affect enzyme activity. Temperature and pH can affect enzyme activity by increase or decreasing the enzymes activity. Optimum enzyme activity occurs at it's optimum pH and temperature levels. 2. Compare optimal temperature for sucrase activity to...
tracking img