Workshop: Biofuels By Ricardo Chiesa Enzymes are proteins that are involved in biological reactions and their mainfunction is to accelerate these processes. The reaction rate consists on how fast or slow areaction takes place. The purpose of this workshop was to work with an enzyme and toalter normal conditions to see how catalysis is affected, and also to see reaction rates. Thebiological functions of enzymes are affected by temperature and pH levels, and the reactionrates are affected by the concentration of substrates and enzymes. The enzyme that Iworked with was the p-nitrophenyl glucopyranoside, an analogous of the cellobiose, anenzyme involved in the breakdown of starch into two glucose molecules. The analogousenzyme, along with water, hydrolyses the starch and breaks it down into a molecule of glucose andp-nitrophenol. This last molecule reflects a yellow color in solution, and thus is very useful fordetermining whether a reaction occurs or not. My lab partner and I worked determining the effectof pH on the reaction rate. We tested it in different pH level solutions (pH 5, pH 6.3, and pH 8.6).It was observed that the pH 5 solution was the only one that turned yellow. This means that pH 5 isthe optimum level for more catalysis to occur. Then, these samples were put into a spectrometer tomeasure the absorbance of each sample. At the end, using a calibration curve with the relationshipof the absorbance numbers and quantity of products, it was determined that more products arevisible as pH level decreases.