Potato Enzyme Lab

This unique shape of an enzyme causes specification and limits the type of substances that can bind to the enzyme’s active site. The active site is the site where the chemical reaction will take place and the substance or substances that bind to the active site are called substrates.

Peroxidase is an enzyme found in potatoes that catalyzes the breakdown of hydrogen peroxide, H2O2, into O2 gas and water. We examined the different pH environments that can affect the enzyme activity during the breakdown of H2O2. In order to do this, we added different levels of pH, low, medium, and high, into different test tubes with the enzyme and H2O2, and we then inverted the tube. The amount of O2 gas produced was then measured and recorded. The result was that the higher pH produced more gas, followed by medium pH, then low pH. The enzymes were more active in the pH of about 10. It increased

The more acidic a substance is the less oxygen it will produce when going through a chemical reaction. During the Lab “How Do Changes in pH Levels Affect Enzymes Activity”, the researcher conducted an experiment to test the effects that an acidic, neutral, and a base substance will have when combine it with hydrogen peroxide. The data table shows that HCL (acidic substance) barley produced any oxygen at all when it was combining with Hydrogen Peroxide. The pH level for HCL was 2.5; this level indicates that the substance was very acidic. When the H2O and NaOH were tested they produced more bubbles than HCL. NaoH produced a little more bubbles than HCL. The pH that NaoH produced was a 9, which is a base. H2O produced more bubbles than both substances;

This experiment looked at how substrate concentration can affect enzyme activity. In this case the substrate was hydrogen peroxide and the enzyme was catalase. Pieces of meat providing the catalase were added to increasing concentrations of hydrogen peroxide in order to measure the effect of hydrogen peroxide concentrations on the enzyme’s activity. The variable measured was oxygen produced, as water would be too difficult to measure with basic equipment.

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

Enzymes are a key aspect in our everyday life and are a key to sustaining life. They are biological catalysts that help speed up the rate of reactions. They do this by lowering the activation energy of chemical reactions (Biology Department, 2011).

In this above reaction, oxygen is released and is used for other cellular purposes, but when it occurs in a test tube, similar to this experiment, the oxygen gas bubbles producing a layer of foam on the surface of the peroxide. The amount of foam and the speed it is produced are forms of measuring the catalase activity. In the next experiments, one would determine the degree of catalase action by calculating the thickness of the foam layer. It is hypothesized that when reacting with: potato, apple, steak, or liver, the plants and animal tissues will react differently.

Enzymes are biological catalysts, which accelerate the speed of chemical reactions in the body without being used up or changed in the process. Animals and plants contain enzymes which help break down fats, carbohydrates and proteins into smaller molecules the cells can use to get energy and carry out the processes that allow the plant or animal to survive. Without enzymes, most physiological processes would not take place. Hundreds of different types of enzymes are present in plant and animal cells and each is very specific in its function.

“Enzymes are proteins that have catalytic functions” [1], “that speed up or slow down reactions”[2], “indispensable to maintenance and activity of life”[1]. They are each very specific, and will only work when a particular substrate fits in their active site. An active site is “a region on the surface of an enzyme where the substrate binds, and where the reaction occurs”[2].

peroxide (H2O2). The enzyme breaks H2O2 into water and oxygen. The production of the oxygen

This investigation will be carried out to investigate the rate of reaction of the enzyme catalase on the substrate hydrogen peroxide.

In this experiment, the concentration of the enzyme catalase was manipulated in a reaction with hydrogen peroxide; the levels of oxygen gas produced from the reaction were recorded. Enzymes are efficient catalysts in biochemical reactions that speed up the pace of the reactions by offering an alternative pathway for reaction (“Enzymes”, n.d.). This alternative pathway or route occurs when the enzyme and the substrate form a reaction intermediate, which occurs due

Enzymes are natural catalysts that work from the ability to increase the rate of reaction by decreasing the activation energy of a reaction. (Blanco, Blanco 2017) An enzyme can do this 10^8- to 10^10 fold, sometimes even 10^15 fold. (Malacinsk, Freifelder 1998) The substrate will momentarily bind with the enzyme making the enzyme-substrate complex, of which the shape of the substrate is complimentary to the shape of the active site on the enzyme it is binding with. There are two main theories as to how an enzymes and substrates interact, the lock-and-key model and induced fit theory. The lock-and-key model suggests that the enzyme has a specific shape that fits the substrate and only that substrate. The induced fit theory says the active site and substrate are able to change shape or distort for the reaction to take place with (Cooper,

Biology 121 KS Lab Report IV 03/06/2018 Jannet Marin Testing the Effects of Temperature and pH on Potato Catalase Activity Introduction: To bear life in the cell, nearly all metabolic processes need enzymes. Enzymes are “macromolecular biological catalysts that help to speed up, or catalyze, chemical reactions.” The activity of enzymes is also affected by changes in the pH and temperatures. However, tremendously high or low pH and temperature values could cause complete loss of activity for most enzymes. Catalase is the most common enzyme found in potatoes and almost all organisms that are exposed to oxygen.

The aim of my investigation is to see how pH affects the activity of potato tissue catalase, during the decomposition of hydrogen peroxide to produce water and oxygen.