Protein Concentration Lab

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;

The results for Benedict’s test for reducing sugars before hydrolysis, the control dH2O had no color change, as well as sucrose and raffinose. Gelatin became a dark blue and egg albumin a light greyish blue. Glucose yielded a dark orange, milk albumin turned orange, and starch had a yellow precipitate. In the Benedict’s test for reducing sugars by hot acid hydrolysis, the control dH2O was blue or no reaction. Glucose turned a brownish-orange; sucrose, a reddish-brown, raffinose, light pink; starch, a dark yellowish-orange; gelatin, violet; milk powder, a light yellow; and egg albumin, a greyish-violet. In the Lugol’s test for polysaccharides, the control dH2O turned yellow or no reaction, as well as glucose, sucrose, raffinose, milk powder and albumin. Starch was clear with blue-violet on the bottom (precipitate) and gelatin turned a slightly opaque white. In the test for polysaccharides remaining after hydrolysis with Lugol’s solution the control dH2O was yellow or no reaction. Glucose, sucrose, raffinose, starch and gelatin also had no reaction. Milk powder had a white precipitate and particle suspension. Egg albumin had an even greater white precipitate and particle suspension. In Biuret’s test for proteins there was no reaction for dH2O, glucose, sucrose, raffinose, and starch. Gelatin, milk powder and egg albumin all turned slightly violet with bubbles.

The purpose of this lab was to test different substances using various procedures to see what biomolecules were present and ultimately find out what restaurant Anna Lyza had eaten at before she died. For the first control test, we used vegetable oil to test for lipids. So, if the solution does not contain lipids, it does not become translucent when placed onto a paper bag square and held up to a light. So, it is a negative result. However, in the presence of lipids, the solution will become translucent when placed onto a paper bag square and held up to a light. Therefore in this case, the result is positive. On the other hand, we used albumin egg to test for proteins in another control test. If the solution does not contain proteins, it will not experience any color change and so it is a negative result. When there are proteins existing in the solution, it will turn bluish/purplish and for this reason it is a positive result. Furthermore in the third control test, we used dextrose to test for simple carbohydrates such as glucose. If the solution does not contain simple carbohydrates, it will not undergo any color change and will remain a blue color. So, it is a negative result in this circumstance. If there are simple carbohydrates present in the solution, the solution will turn reddish and so the result is positive. For the last control test, we used starch solution to test

This Lab Report is an analysis of the results of a two-part experiment. In the first part, we used a gel filtration column to separate the components of a mixture composed of protein and non-protein molecules. By doing so we hoped to obtain fractions that contained single components of the mixture, while also gaining insight into the relative molecular weight of each component compared to each other. We would then plot these fractions onto nitrocellulose paper in order to determine which fractions had protein. In the second part, we would use the fractions which we had determined had protein to conduct an SDS-PAGE. By doing so we hoped to determine an estimate on the molecular weight of the proteins present in each fraction by comparing it to a tracker dye composed of a variety of molecules of differing molecular weight.

In order to examine the variation in sensitivity of lysozyme, gelatin, and BSA, the absorbance reading was obtained using the Bradford and BCA assay

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.

A spectrophotometer’s purpose is to use colors of the light spectrum to determine the concentration of light absorbing molecules in a solution. (p.59) In this particular lab, our mission was to determine the protein concentration and the standard curve of the unknown sample of BSA. This, by preparing five dilutions of the unknown solution of BSA together with other known concentrations, and then experimenting by observing how the concentrations were passed through the spectrophotometer. The outcome resolved in the absorption levels being decreased, and this

The purpose of this experiment was to find out the nutrient content of unidentified food samples and to use chemical reagents to see if the unidentified foods for sugar, starch, protein and fat (lipid) content. After comparing the color changes in each unknown substance then you will be able to see the amount of sugar, starch, protein or fat there is in the unknown substance.

2. Four unknown samples were included in the lab kit: flax seed meal, potato starch, egg whites, and dried milk. Using the results of the biochemical testing, determine which number corresponds to the correct unknown. (8 points)

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.

a) Tap and drag over the area of the graph where the resting heart rate is displayed to select the data.

* Temperature * Method of measuring solutions I will use equal amounts of trypsin, milk, PH, buffer and distilled water in all the experiments and will use the same measuring equipment to ensure fair representation of the effect of different PH on digestion.

Protein purification is a process that can be employed to separate a single protein from a larger starting material which may be anything from an organ to a cell. Isolating a purified protein from a larger fraction enables further analysis such as determination of amino acid sequence, potential biological function, and even evolutionary relationship. (Cuatrecasas 1970) In this experiment, the enzyme lactate dehydrogenase will be purified, this enzyme is found extensively in human cells and catalyzes the conversion of lactate to pyruvate, an essential part in energy production. LDH is a key part of anaerobic energy production especially within glycolysis in which LDH catalyzes the conversion of the reverse reaction, pyruvate to lactate, generating NAD+ from NADH, reproducing the oxidized form of the coenzyme which can be used for oxidative respiration. (Markert 1963) Due to the fact that number of purification steps correlates with the purity of the protein multiple purification techniques will be used to isolate a pure form of LDH. LDH will be isolated from a larger “cytosol” fraction collected from a homogenized rat liver in a previous fractionation exercise. Of the procedures that will be used to isolate and purify proteins from a larger fractionate are a set of techniques collectively known as chromatography. These techniques all have the same premise, in that they consist of a stationary phase, also known as the

To find the effect of temperature on the activity of an enzyme, the experiment deals with the steps as follows. First, 3 mL if pH 7 phosphate buffer was used to fill three different test tubes that were labeled 10, 24, and 50. These three test tubes were set in three different temperature settings. The first test tube was placed in an ice-water bath for ten minutes until it reached a temperature of 2° C or less. The second tube’s temperature setting was at room temperature until a temperature of 21°C was reached. The third tube was placed in a beaker of warm-water until the contents of the beaker reached a temperature setting of 60° C. There were four more test tubes that were included in the procedure. Two of the test tubes contained potato juice were one was put in ice and the other was placed in warm-water. The other two test tubes contained catechol. One test tube was put in ice and the other in warm water. After

Name ____________________________ I) Introduction All cells contain four major types of macromolecules: carbohydrates, lipids, nucleic acids, and proteins. In today’s lab, we will be studying three of the four-proteins, carbohydrates and lipids. Various chemical tests can be used to detect the presence of each of these molecules. Most of the tests involve a color change visible to the eye. If a color change is observed, the test is considered positive. If the color change is not observed, the test is negative, indicating that a particular molecule is not present. In all the chemical tests we will be performing, we will also be using a control. In most cases, the control will be a sample of