Introduction to Biofuels: Enzyme Action

Experiment #7 from Investigating Biology through Inquiry

In this Preliminary Activity, you will use a spectrophotometer to determine p-nitrophenol concentration. You will first produce a p-nitrophenol containing sample with the reaction. Next, you will determine the absorbance values for a set of p-nitrophenol solutions with known concentrations in order to create a standard curve. When a graph of absorbance vs. concentration is plotted for the standard solutions, a direct relationship should result. The direct relationship between absorbance and concentration for a solution is known as Beer’s law. You will then determine the p-nitrophenol concentration of your prepared sample by measuring its absorbance and then finding the corresponding concentration on the standard curve. Because the relationship is linear, you could also calculate the

p-nitrophenol concentration using the formula for the standard curve. You will also determine the initial rate of your p-nitrophenol producing reaction.

After completing the Preliminary Activity, you will first use reference sources to find out more about biofuels and the cellobiase catalyzed reaction that produces p-nitrophenol before you choose and investigate a researchable question. Some topics to consider in your reference search are:

• catalyst
  
• enzyme
  
• biofuel
  
• ethanol
  
• cellulose
  
• cellobiose
  
• cellobiase
  
• substrate
  
• p-nitrophenol
  
• Beer’s law