P-Nitrophenol Enzyme Lab Report

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;

In this lab or experiment, the aim was to determine the following factors of enzymes: (1) the effects of enzymes concentration the catalytic rate or the rate of the reaction, (2) the effects of pH on a particular enzyme, an enzyme known and referred throughout this experiment as ALP (alkaline phosphate enzyme) and lastly (3) the effects of various temperatures on the reaction or catalytic rate. Throughout the experiment 8 separate cuvettes and tubes are mixed with various solutions (labeled as tables 1,3 & 4 in the apparatus/materials sections of the lab) and tested for the effects of the factors mentioned above (concentration, pH and temperature). The tubes labeled 1-4 are tested for pH with pH paper and by spectrophotometer, cuvettes 1a-4a was tested for concentration and cuvettes labeled 1b-4b was tested for temperature in four different atmospheric conditions (4ºC, 23ºC, 32ºC and 60ºC) to see how the enzyme solution was affected by the various conditions. After carrying out the procedures the results showed that the experiment followed the theory for the most part, which is that all the factors work best at its optimum level. So, the optimum pH that the enzymes reacted at was a pH of 7 (neutral), the optimum temperature that the reactions occurs with the enzymes is a temperature of 4ºC or

In the experiment we used Turnip, Hydrogen Peroxide, Distilled Water, and Guaiacol as my substances. On the first activity, Effect of Enzyme concentration of Reaction Rate for low enzyme concentration, we tested three concentrations of the turnip extract, and hydrogen peroxide. For the Turnip Extract I used 0.5 ml, 1.0 ml, and 2.0 ml. For hydrogen peroxide we used 0.1 ml, 0.2 ml, and 0.4 ml. We used a control to see the standard, and used a control for each enzyme concentration used. The control contains turnip extract and the color reagent, Guaiacol. We prepared my substrate tubes separately from the enzyme tubes. My substrate tube

Colorimetric assay is a process of determining a concentration of a solution based on absorbance of light. The purpose of this lab is to determine if the Bradford assay is an accurate way to determine an unknown concentration of two samples of protein. The Bradford assay is done by measuring wavelength of light passing through a cuvette filled with Bradford dye and concentrations of PBS and proteins. After the cuvettes are mixed they are placed into a spectrophotometer to measure wavelength. The wavelength given will be used to plot a standard curve based on concentration (x-axis) and wavelength (y-axis). The standard curve is then used to measure an educated guess on the concentrations of unknown protein concentrations. We hypothesized that if we use the Bradford assay and colorimetric spectrophotometry we can determine an accurate concentration of two unknown concentrations of proteins. The results of this lab failed to reject our hypothesis based on accurate measurements of protein concentrations. The standard curves are drawn with a linear increasing slope. The Bradford assay is an accurate way to demine the concentration of an unknown concentration.

These results shown from this experiment led us to conclude that enzymes work best at certain pH rates. For this particular enzyme, pH 7 worked best. When compared to high levels of pH, the lower levels worked better. The wrong level of pH can denature enzymes; therefore finding the right level is essential. The independent variable was the amount of pH, and the dependent being the rate of oxygen. The results are reliable as they are reinforced by the fact that enzymes typically work best at neutral pH

Enzymes are catalysts that function to speed up reactions; for example, the enzyme sucrose speeds up the hydrolysis of sucrose, which breaks down into glucose and fructose. They speed up reactions but are not consumed by the reaction that is taking place. The most important of the enzyme is the shape as it determines which type of reaction the enzyme speeds up. Enzymes work by passing/lowering and energy barrier and in doing so; they need to bind to substrates via the active. Once they do, the reaction speeds up so much more quickly than it would without the enzyme. Coenzymes and cofactors aid the enzyme when it comes to binding with the substrate. They change the shape of the active site so the substrate can bind properly and perform its function.

The optimum pH level would be pH 7. This is because this is where the highest amount of enzyme activity is taking place.

The hypothesis tested in this experiment was, if the temperature of enzyme catalysis were increased, then the reaction rate would increase, because enzyme-catalysis reacts by randomly colliding with substrate molecules, and the increase in temperature increases the speed of collision or reaction rate. The final data collected for the experiment was positive with my hypothesis. The coffee filter, covered in potato solution, sank and rose at a faster pace in the hydrogen peroxide when the temperatures were raised.

Lactose is a sugar that can be put into smaller molecules, glucose and galactose. Lactose is when you are not able to digest milk and dairy meaning that the enzyme lactase that breaks down lactose is not functioning properly. ONPG was used as a substitute for lactase because even though it is colorless it helps show enzyme activity by turning yellow. This experiment measured the absorbance ONPG when exposed to lactase within an environment of different salinity’s. The enzyme, lactase, was obtained by crushing a lactaid pill and then was added into four cuvettes. ONPG and salt solution of different concentrations were added and their levels of absorption was measured by a spectrophotometer. The results showed that higher salt concentrations have a lower level of absorption. There were 4 cuvettes and within those cuvettes that solutions within them were being tested and the results showed the more salt solution added with the lactase the lower the absorbance. The less salt solution there was a higher rate of absorbance. The data supported the hypothesis that with increasing NaCl concentration there would be a decrease in enzyme activity.

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

To prevent fluctuation in the pH, a solution known as a “buffer solution” was used in the experiment. Buffer solutions are mixtures of at least two chemicals which counteract the effect of acids and alkalis. Therefore, when a small quantity of alkali or acid solution is added the pH of the enzyme doesn’t change.

After the substrate solution was added, five drops of the enzyme were quickly placed in tubes 3, 4 and 5. There were no drops of enzyme added in tubes 1 and 2 and in tube 6 ten drops were added. Once the enzyme solution has been added the tubes were then left to incubate for ten minutes and after five drops of DNSA solution were added to tubes 1 to 6. The tubes were then placed in a hot block at 80-90oC for five minutes. They were then taken out after the five minute period and using a 5 ml pipette, 5 ml of distilled water were added to the 6 tubes and mixed by inversion. Once everything was complete the 6 tubes were then taken to the Milton Roy Company Spectronic 21 and the absorbance of each tube was tested.

An enzyme is a protein that acts as a catalyst which reduces the activation energy needed for a chemical reaction. Without the presence of enzyme, cell reactions would take so long that they would detectable. During a reaction, in the presence of an enzyme, the substrate first creates a complex with the enzyme. While the substrate is a part of the complex, it’s converted into the product. Then, finally, the complex dissociates from the molecule which allows the release of the enzyme and formed product. An enzyme’s activity depends on a variety of conditions which includes the pH level and temperatures. Phosphorylase is an enzyme that catalyze the addition of a

Organisms cannot depend solely on spontaneous reactions for the production of materials because they occur slowly and are not responsive to the organism's needs (Martineau, Dean, et al, Laboratory Manual, 43). In order to speed up the reaction process, cells use enzymes as biological catalysts. Enzymes are able to speed up the reaction through lowering activation energy. Additionally, enzymes facilitate reactions without being consumed (manual,43). Each enzyme acts on a specific molecule or set of molecules referred to as the enzyme's substrate and the results of this reaction are called products (manual 43). As a result, enzymes promote a reaction so that substrates are converted into products on a faster pace (manual 43). Most enzymes are proteins whose structure is determined by its sequence of its amino acids. Enzymes are designed to function the best under physiological conditions of PH and temperature. Any change of these variables that change the conformation of the enzyme will destroy or enhance enzyme activity(manual, 43).

Enzymes are an important part of all metabolic reactions in the body. They are catalytic proteins, able to increase the rate of a reaction, without being consumed in the process of doing so (Campbell 96). This allows the enzyme to be used again in another reaction. Enzymes speed up reactions by lowering the activation energy, the energy needed to break the chemical bonds between reactants allowing them to combine with other substances and form products (Campbell 100). In this experiment the enzyme used was acid phosphates (ACP), and the substrate was p-nitrophenyl phosphate.