Reaction Rates of Barley Alpha-Amylase Enzyme with Substrate Starch at Different Ph’s and Temperatures
Abstract Enzymes are proteins that lower the activation energy needed for chemical reactions. The two main environmental factors that can affect the enzyme’s activity are temperature and pH, and each enzyme works best at a particular temperature and pH. The purpose of this enzyme kinetic experiment was to observe the effect of temperature and pH on the reaction of barley alpha-amylase enzyme with starch substrate and establish the optimum temperature and pH for this reaction. The optimum temperature and pH for the reaction of alpha-amylase and starch was predicted to be a temperature of 50°C and a pH of 5. The optimum temperature and pH for the reaction was determined by monitoring the reaction rate of alpha-amylase at different temperatures and pH’s by means of using a spectrophotometer to measure the disappearance (in absorbance) of the substrate starch. As a result, the absorbance of the substrate starch decreased at different rates for each temperature and pH as time continued to increase. The results showed that the reaction rate with the enzyme is highest when it reaches a temperature of 50°C and has a pH of 5. Therefore, a farmer should grow barley seeds in soil that has a temperature of 50°C and a pH of 5.
Introduction
The purpose of this enzyme kinetic experiment was to observe the effect of temperature and pH on the reaction of barley alpha-amylase enzyme with starch substrate and establish the optimum temperature and pH for this reaction.
Enzymes are essential to all living organisms. An enzyme is a globular protein that acts as a catalyst, a chemical agent that speeds up reactions without being consumed by the reaction. They lower the activation energy needed for chemical reactions, allowing the reactant molecules to absorb enough energy to reach the transition state (Vliet 2008). When an enzyme binds to a substrate, it forms an enzyme-substrate complex. The substrate-enzyme complex allows the enzyme to react with the substrate in order
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