Catechol Oxidase Lab Report

The preparation for the experiment started by gathering the solutions of enzyme Peroxidase, substrate hydrogen peroxide, the indicator guaiacol and distilled water. Two small spectrometer tubes and three large test tubes with numbered labels. In addition, one test tube rack, one pipet pump and a box of kimwipes were also gathered. Before the experiment, the spectrometer must be set up to use by flipping the power switch to on. Following, the machine was warmed up for 10 minutes and the filter lever was moved to the left. In addition, I set the wavelength to 500 nm with the wavelength control knob. Before the experiment, I had to create the blank solution by pipetting 0.1 ml of guaiacol, 1.0 ml of turnip extract and 8.9 ml water into tube #1. Following the creation of the blank, a control 2% solution was created.

The human body is an incredible system that is capable of working a multitude of diverse functions. Without the help of the many different protein molecules, the human body would not be able to function properly. One major group of proteins called enzymes are mandatory for essential life. These proteins are constantly at work assembling molecules, metabolizing energy, and fighting off infections. An enzyme is a macromolecule that acts as a catalyst that speeds up a chemical reaction without being consumed by the reaction. Without these proteins, these reactions would take place too slowly to keep us alive. Essential parts in your body like vitamins and minerals cannot do any work without

The role of an enzyme is to catalyse reactions within a cell. The enzyme present in a potato (Solanum Tuberosum) is catechol oxidase. In this experiment, the enzyme activity was tested under different temperature and pH conditions. The objective of this experiment was to determine the ideal conditions under which catechol oxidase catalyses reactions. In order to do this, catechol was catalyzed by catechol oxidase into benzoquinone at diverse temperatures and pH values. The enzyme was exposed to its new environment for 5 minutes before the absorbance of the catechol oxidase was measured at 420 nm using a spectrophotometer. The use of a spectrophotometer was crucial for the collection of data in this experiment. When exposed to hot and cold temperatures, some enzymes were found to denature causing the activity to decrease. Similarly, when the pH was too high or low, then the catechol oxidase enzyme experienced a significant decrease in activity. It can be concluded after completing this experiment that the optimal pH for catechol oxidase is 7 and that the prime temperature is 20º C. Due to the fact that the catechol oxidase was only tested under several different temperatures and pH values, it is always possible to get a more precise result by decreasing the increments between the test values. However, our experiment was able to produce accurate results as to the

Temperature can affect the reaction of catechol oxidase by speeding up or slowing down the reaction. I was able to see what happened to the absorbance after changing the temperature of the catechol oxidase solution. I did this by heating and cooling the solutions to measure the absorbances in hot, cold, warm, and room temperature. Then the data was compared to see how the temperature effected the solution. The catechol oxidase solutions reacted best in room temperature (twenty-three degrees Celsius) and the worst in the cold (zero degrees Celsius). I concluded that temperature really does affect the way catechol oxidase reacts.

Lab six requires students to observe the effects of pH and enzyme concentration on catecholase activity. Enzymes are organic catalysts that can affect the rate of a chemical reaction depending on the pH level and the concentration of the enzyme. As pH comes closer to a neutral pH the enzyme is at its greatest effectiveness. Also at the absorbance of a slope of 0.0122 the enzyme is affected greatly. The pH effect on enzymes can be tested by trying each pH level with a pH buffer of the same pH as labeled as the test tube and 1mL of potato juice, water, and catechol. This is all mixed together and put in the spectrophotometer to test how much is being absorbed at 420nm. As the effect on enzyme concentration can be tested almost the same way. This part of the exercise uses different amounts of pH 7-phosphate buffer and potato juice, and 1mL of catechol mixed together in a test tube. Each substance is put in the spectrophotometer at a wavelength set tot 420nm. The results are put down for every minute up to six minutes to see how enzyme concentration affects reaction rate. The results show that the pH 8 (0.494) affects the enzyme more than a pH of 4 (0.249), 6 (0.371), 7 (0.456), and 10 (0.126). Also the absorbance is greatest at a slope of 0.0122 with test tube C that has more effect on the reaction rate, than test tube A, B, and D.

Within the experiment, pure catechol was mixed with different concentrations of catechol oxidase and the rate at which each solution produced benzoquinone was measured. The amount of benzoquinone made throughout the trials was measured by using a colorimeter to measure the level of “brownness” of the liquid. The colorimeter worked by shining a light through the liquid and then measuring that light on the other side to see how much of it was absorbed. In this experiment, absorbance of blue light was measured because blue light is absorbed by the color brown. The amount of blue light absorbance was measured every 15 seconds for five minutes. Because enzymes speed up reactions, more enzymes would cause the reaction to be even faster.1

In order to see the effects of pH and temperature on the enzymatic reaction of catechol oxidase when separated from potato tissue. We used a spectrophotometer to measure how much blue light energy is absorbed by benzoquinone. Benzoquinone is a product of catechol when it has been oxidized by different temperatures and pHs. We hypothesized that the benzoquinone absorbance rate would be faster when the pH added to the cuvettes were greater than the pH of the potato tissue. The pH of the potato tissue was pH 6. Our results show that pH 7 had the faster absorbance rate, slightly slower at pH 4, and slowest at pH

The purpose of this experiment was to record catalase enzyme activity with different temperatures and substrate concentrations. It was hypothesized that, until all active sites were bound, as the substrate concentration increased, the reaction rate would increase. The first experiment consisted of five different substrate concentrations, 0.8%, 0.4%, 0.2%, 0.1%, and 0% H2O2. The second experiment was completed using 0.8% substrate concentration and four different temperatures of enzymes ranging from cold to boiled. It was hypothesized that as the temperature increased, the reaction rate would increase. This would occur until the enzyme was denatured. The results from the two experiments show that the more substrate concentration,

Catechol, in the presence of oxygen is oxidized by catechol oxidase to form benzoquinone (Harel et al., 1964). Bananas and potatoes contain catechol oxidase that acts on catechol which is initially colorless and converts it to brown (Harel et al., 1964). In this experiment, the effect of pH on the activity of catechol oxidase was conducted using buffers ranging from pH2 to pH10. Two trials were conducted due to the first trial results being altered by an external factor. The results were acquired by taking readings every 2 minutes for 20 minutes from a spectrophotometer and then recorded on to the table. The data collected in the table were then made into graphs to illustrate the influence of pH on the catechol oxidase catalyzed reaction. After analysis, the data revealed that pH did have a significant influence on the enzyme as recorded by absorbance per minute. However, the data was collected was not accurate due to external factors, thus the results are debatable and should be experimented again for validation.

Turnips and horse radish roots are rich source of this enzyme. In this experiment, we would carry out a reaction between hydrogen peroxide and guaiacol which is colorless dye, using peroxidase as a catalyst, to produce water and an oxidized form of guaiacol which is brown. The formation of brown color would serve as an indicator that the breakdown of Hydrogen Peroxide took place. The enzyme activity would be directly proportional to the brown color intensity. The color intensity would be measured using a spectrophotometer and standardized to find the corresponding concentration for each absorbance unit.

Abstract: Enzymes, catalytic proteins that at as catalysis which makes the process of chemical reactions more easily. There are two main factors that actually affects enzymes and their functions which are temperature and pH. Throughout this experiment, the study how pH and peroxidase affects each other and the enzyme was made. The recordings of how the enzymes responded when it was exposed to four different pH levels to come up with an optimum pH which was predicted in the hypothesis and the IRV at the end.

In this experiment concerning the activity of enzymes we tested the different effects of various concentrations, pH, Temperature, and Inhibitors over intervals of time. For the effects of concentration of enzyme extract, or peroxidase we mixed six of seven tubes to get three different concentrations of extract. By doing this we wanted to know whether the concentration would positively or negatively affect the activity of the enzyme, in which we predicted that the concentration would increase the activity. The three extract concentrations being 0.5ml from the mixing of tubes 2 and 3, 1.0ml from tube 4 and 5, and 2.00ml from 6 and 7, while the first tube of the seven that wasn’t mixed was the control containing zero extract. The control and the mixed tubes together made 8ml, and was poured into cubettes to be placed in the spectrometer at an absorbance of 500nm.

The experiments involved PH buffers of different pH were added to potato juice, water, and the enzyme catecholase. The mixture was then subjected to spectrophotometer at a wavelength of 420nm taking the absorbance readings. In the second experiment, a phosphate buffer of PH 7.0 was used in different measures together with different measurement of potato juice and the enzyme catecholase then subjected to the spectrophotometer at a wavelength of 420nm. The data collected inform of table and analyzed using descriptive statistics such as line graph and later interpreted, showing that PH and enzyme concentration do affect the rate of enzyme reaction

This experiment is designed to analyze how the enzyme catalase activity is affected by the pH levels. The experiment has also been designed to outline all of the directions and the ways by which the observation can be made clearly and accurately. Yeast, will be used as the enzyme and hydrogen peroxide will be used as a substrate. This experiment will be used to determine the effects of the concentration of the hydrogen peroxide versus the rate of reaction of the enzyme catalase.

Hydrogen peroxide is a toxic byproduct of cellular functions. To maintain hydrogen peroxide levels the catalase enzyme deconstructs hydrogen peroxide and reconstructs the reactants into oxygen gas and water. The catalase enzyme is found inside cells of most plants and animals. Regulating the levels of hydrogen peroxide is crucial in homeostasis and analyzing it’s optimal conditions for performance is just as important. To understand the optimal environment for this enzyme, they are put into different environments based off protein activity (enzymes are proteins). Catalase samples will be put into different hydrogen peroxide environments based off pH and temperature. The more active the enzyme, the more oxygen and water it will produce. Enzyme activity can be seen through the release of oxygen in the hydrogen peroxide. Since oxygen cannot be accurately measured, the data will consist of the longevity of the reaction in different environments. If the pH is higher than 7, then the reaction rate will increase due to the ample amount of hydrogen ions in the hydrogen peroxide. However the pH level cannot be higher than 10 or else there will be too many hydrogen atoms in the peroxide for the enzyme to be able to deconstruct them. If the temperature is increased, then the reaction rate will increase due to the ample amount of energy and movement in the hydrogen peroxide and enzyme.