The Effect Of Varying Ph Values On The Enzymatic Activity Of Glucose Oxidase

The objective of this experiment was to determine the effects of varying pH values on the enzymatic activity of glucose oxidase. This enzyme specifically oxides D-glucose while simultaneously reducing oxygen into hydrogen peroxide, whose catalysis by the enzyme horseradish peroxidase coupled with this reaction is broken down into its constituent parts of water and oxygen. The reaction rate of glucose oxidase was tested at four distinct pH levels of 3, 4, 5, and 6. The absorbency of each solution was determined through the addition of guaiacol and the use of a spectrophotometer to record the values of absorption for each solution over the course of two minutes. The data presented through the use of tables and graphs reveals that at each pH level tested the enzyme remained functional, demonstrating that the range of pH for this enzyme is at least 3 to 7. According to the graphs, it appears as though a pH of 5 allowed glucose oxidase to function most efficiently, suggesting that a pH closest to 5 would prove to be optimal for this particular enzyme. Introduction Life on earth would not be possible without enzymes. Enzymes are proteins whose primary function is to act as catalysts in metabolic pathways by binding to specific molecules, called substrates in this context, at their active site. They are defined by two distinctive characteristics, the first being their ability to increase the rate of a reaction without being used up or modified by the reaction