The Effects that 1%, 4%, and 16% Sodium Chloride (NaCl) Concentration Had on the Rate of Reaction of Catecholase Enzymes in a Potato (Solanum tuberosum).
Abstract
Enzymes are a key component of a cell. They make chemical reactions happen faster because they lower the activation energy to make the chemical reaction occur. Most of the time, it is best if enzymes produce as efficiently as possible, but in some cases it is better if they do not, when dealing with potatoes (Solanum tuberosum). If the catecholase enzyme of the potato is hindered, it is less likely to brown when it is cooked. To see how efficient sodium chloride is at slowing down these enzymes, the experiment measured the rate of reaction when the enzymes were exposed
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There are three factors that will alter an enzyme: temperature, pH and salt. All three will change the structure of the enzyme by denaturation and rendering it useless when a drastic change occurs from levels that are normal. A slight alteration can speed up reaction to certain saturation or slow the process of reaction. Enzymes have a substrate: the substrate for the catecholase enzyme is catechol and oxygen. When the substrate combines with the catecholase enzyme of a potato, the product is a reddish brown color called benzoquinone. This product is what turns fruits and vegetables brown (Briggs and others 2010). Therefore, slowing or stopping the process of would increase shelf life of some food, or at least make the foods appearance appetizing much longer. The equation for this chemical reaction is:
Enzyme Substrate Product Catechol + Oxygen Catecholase --------------------- Benzoquinone The hindering of the Benzoquinone could alter the production, and could lower the cost of produce. Nathalie Santis and others (2005) preformed an experiment to see the effects of various NaCl solutions on thin slices of potato that were fried. The potatoes were sliced 3mm thick and 30mm in diameter, fourteen slices in all. All fourteen were blanched at 70°C for five minutes. Seven were placed in pure water at 26°C and the other seven went into several NaCl solutions (0.6%, 1.2%, 1.8%, 2.4%, 3.0%, 6.0% and
The procedure of this lab is to determine if liver and potato cells contain natural buffers that resist large change in pH as 1. NaCl or 1. NaOH are added to the solution.
It is known that enzymes are protein catalysts that speed up the rate of a chemical reaction with being consumed, or altered when the reaction takes place. These chemical reactions occur in the active site, which is where the enzyme is combined to a substrate. Potatoes will go bad if stored in the wrong temperature and if the pH of the potato was altered.
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.
Enzymes will denature if they get too hot or cold or if the pH of the solution they are in is too high or too
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.
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
In the exercise # 2 we observed the effect of substrate concentration, enzyme concentration, pH and temperature on enzyme activity. All the data showed that once potato extract was added to catechol and water the reaction varied dependent on the level of catechol. As in
Hypothesis: If we decrease the level of pH in the enzyme Amylase, it will not be able to denature the carbohydrates in the potato starch solution after 10 drops because enzymes are very sensitive to pH levels and lowering it too much will compromise its ability to break them down.
The purpose of this experiment was to test the effects that temperature, pH, and substrate
The Effects of Sodium Chloride on Enzyme Activity Abstract The function of enzymes and how external environmental factors are discussed along with how the effects of such factors can be measured through experimentation. The method that was used to conduct the experiment is described thoroughly, as is the materials that were used with the method. The results of the data using the measured reaction activity of the enzyme catechol oxidase with the substrate catechol are reported, referring to the graphs showing the data.
Enzymes are high molecular weight molecules and are proteins in nature. Enzymes work as catalysts in biochemical reactions in living organisms. Enzyme Catecholase is found on in plants, animals as well as fungi and is responsible for the darkening of different fruits. In most cases enzymatic activities are influenced by a number of factors, among them is temperature, PH, enzyme concentration as well as substrate concentration (Silverthorn, 2004). In this experiment enzyme catecholase was used to investigate the effects of PH and enzyme concentration on it rate of reaction. A pH buffer was used to control the PH, potato juice was used as the substrate and water was used as a solvent.
The use of multiple test tubes and Parafilm was used for each experiment. Catechol, potato juice, pH 7 phosphate buffer, and stock potato extract 1:1 will be used to conduct the following experiments: temperature effect on enzyme activity, the effect of pH on enzyme action, the effect of enzyme concentration, and the effect of substrate concentration on enzyme activity. For the temperature effect on enzyme activity, three test tube were filled with three ml of pH 7 phosphate buffer and each test tube was labels 1.5 degrees Celsius, 20 °C, and 60 °C. The first test tube was placed in an ice-water bath, the second test tube was left at room temperature, and the third test tube was placed in approximately 60°C of warm water. After filling the test tubes with three ml of the
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,
Almost all enzymes need specific conditions for them to function. The conditions include temperature, pH level, and concentration of salt. Enzymes have optimal conditions. If they are changed, the enzyme may denature and deactivate. If that happens, the enzyme would not be able to catalyze the reaction, and the reaction rate would decrease (Worthington 2010).
Introduction: Starting out with some background information, I know that enzymes are biological catalysts. The enzyme that I used for this experiment was potato juice. Enzymes make reaction rates go faster. They lower activation energy, making chemical reactions. Temperature has an effect on canola cultivars. The higher temperature decreased stem diameter, but room temperature had thicker stems. So I believe the same will happen for the catechol oxidase; the solution will react faster at room temperature. Other enzymes can also have different effects such as the enzyme in cattle serum. The enzyme lost activity in room temperature. With that being said room temperature can also be detrimental with specific enzymes. Fungus also