Turnip Peroxidase Lab Report

The objective of this experiment is to test the presences of catechol oxidase in various fruits and vegetables. Our group hypothesis states that, If catechol oxidase is present in the selected extracts, the null hypothesis is that catechol oxidase is not present in the selected extracts. Next, the prediction would be, if catechol oxidase doesn't differ with other enzyme sources, then the rates will

To catalyze a reaction, an enzyme will grab on (bind) to one or more reactant molecules. In this experiment we examined how increasing the volume of the extract added to the reaction would affect the rate of the reaction. The enzyme used was horseradish peroxidase which helps catalyze hydrogen peroxide. Using different pH levels, the absorbance rate of the reaction was measured to see at which condition the enzyme worked best. The rates of absorption were calculated using a spectrophotometer in 20 second intervals up to 120 seconds. It was hypothesized that the optimal pH for the enzyme was pH 7 while the 1.0 ml peroxidase would have the best reaction rate. At the end of the experiment the results prove the hypothesis to be incorrect.

About pH: If the pH level is less than 5, then the speed of the enzyme reaction will be slower.

LABORATORY REPORT Activity: Enzyme Activity Name: Natalie Banc Instructor: Elizabeth Kraske Date: 09.22.2016 Predictions 1. Sucrase will have the greatest activity at pH 6 2. Sucrase will have the greatest activity at 50 °C (122 °F) 3. Sucrase activity increases with increasing sucrose concentration 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

All chemical reactions that occur in a living organism depend on the actions of enzymes, and function in a temperate environment similar to the body temperature of a living organism. Each enzyme has particular conditions under which is functions optimally, and its activity can be altered by different factors. This includes the pH it is exposed

Catalase is an enzyme normally found in many plant and animal tissues. Its purpose is to destroy toxic substances like hydrogen peroxide which is a byproduct in many cellular reactions. In this lab, we will use a catalase solution from yeast and determine the effect of substrate concentration on the action of this enzyme. The substrate of the enzyme will be different concentrations of hydrogen peroxide (H2O2). Catalase works by the following mechanism :

In class, a series of experiments were performed that pertained to the enzyme known as catalase, which converts hydrogen peroxide into oxygen. Due to peroxide being toxic to the tissues of both plants and animals, both possess the enzyme catalase, which breaks into two non-toxic compounds: water and oxygen gas. Enzymes are proteins that react to certain substrates to create a product, and continue doing so afterwards.

Enzymes are organic compounds which act as catalysts and speed up biological reactions in biological organisms. They are not destroyed or changed during the reaction but rather they are used over and over again to catalyze many more reactions. Their activity may be affected and altered by factors such as temperature, substrate concentration, enzyme concentration and Ph.

The reason for this experiment was to observe the way temperature affected the amylase activity, in both bacterial and fungal. It is predicted that temperature can affect the way an enzyme is able to break down. After analyzing the results in tables 1 and 2, one can state that the data provide us with sufficient evidence to support that when an optimal temperature of an enzyme is not correct, the functions will be reduced or denatured. The importance of enzymes can be emphasized by the different functions they have in the body. The three main enzymes in organisms are metabolic, digestive and food enzymes. Metabolic are responsible for the speeding up of reactions in a cell, they work as catalysts and are helpful in detox. Digestive are found

Enzymes are biological catalysts that increase the rate of a reaction without being chemically changed. Enzymes are globular proteins that contain an active site. A specific substrate binds to the active site of the enzyme chemically and structurally (4). Enzymes also increase the rate of a reaction by decreasing the activation energy for that reaction which is the minimum energy required for the reaction to take place (3). Multiple factors affect the activity of an enzyme (1). These factors include the pH and the temperature of the solution (1). Most enzymes have a preferred temperature and pH range (2). The preferred temperature for catalase falls between the ranges of thirty five to fifty degrees Celsius (4). Temperatures that are too high denature the enzyme and halt the enzyme’s activity (2). Catalase denatures starts to denature at fifty five degrees Celsius (2). Reactions in the human body produce hydrogen peroxide as a product (1). Since hydrogen peroxide is poisonous to the human body, catalase catalyzes hydrogen peroxide into water and oxygen (2 H2O2 → 2 H2O + O2) (1). According to the collision theory, a reaction can only occur if particles collide with sufficient energy to overcome the activation energy and with correct geometrical orientation (3). Increasing temperature increases the kinetic energy of the particles which means that an increase in temperature will increase the speed of the hydrogen peroxide and the catalase molecules which

As pH increases or decreases to get closer to the optimal pH --in this case it is 7 for this particular enzyme-- the rate of reaction peaks and is highest at that point, which is described by the molecular shape and structure of the enzyme at its optimal pH. When turnip peroxidase is at pH 7, the active site is able to fit perfectly with the substrate, therefore explaining why the reaction rate is fastest at this point. Accordingly, if the active site is disrupted, the substrate cannot fit perfectly causing the reaction rate to slow down. This can be supported by the data because the reaction rate gradually increased from pH 3 to pH 7 and reached its maximum at pH 7. Once it did reach the optimal pH, the reaction rate continuously decreased

To investigate the effects of changing the concentration of the enzyme catalase that it has on the rate of breaking down the Hydrogen Peroxide solution.

In this experiment it was examined whether the enzyme peroxidase will work fastest in a pH of 8.0. We placed the enzyme peroxidase in a reaction with guaiacol and hydrogen peroxide in four different pH solutions. Then recorded the absorbencies for each reaction until all substrates were used up, and calculated the initial reaction velocities for each. We found that the reaction in a pH 7.0 solution had the highest initial reaction velocity. Over-all this study shows that the enzyme peroxidase will work the fastest in a 7.0 solution.

In order to determine if temperature affects the ability of Peroxidase to react, we measured the reaction rate of the same solution exposed to different temperatures. Solutions were exposed to a 4-degree, 22-degree, 32-degree, or 60-degree Celsius environment then measured by a spectrophotometer. The solution left in the 22-degree environment had the highest reaction rate, while the solution exposed to the 60-degree water bath was not able to react at all. We also tested to see if Peroxidase was able to recover its catalytic ability after being exposed to sub optimal temperatures. After being brought to optimal temperatures the solutions were still able to react,

Cooper, G. (2018). The Central Role of Enzymes as Biological Catalysts. [online] Ncbi.nlm.nih.gov. Available at: https://www.ncbi.nlm.nih.gov/books/NBK9921/ [Accessed 7 Mar.