In this experiment, we will explore the properties of fresh potato extract in Phosphate buffer pH6 containing the enzyme polyphenol-oxidase and measure the different concentration of this enzyme activity by observing the production of pink/gold melanin, when 0.1% catechol and phosphate buffer pH6 is mixed into the solution. At this stage of the experiment, we are assuming that all other variables that can act as inhibitors of the enzymatic activity such as temperature or pH levels are under control. Fruits and vegetables are known to have small amounts of catechol and polyphenol-oxidase (enzyme), which are the cause of the production of browning effect in the out-layer skin or liquid of the fruit or vegetable when it is damaged. Polyphenol-oxidase …show more content…
In this situation we were able to observe the production of pink/ gold melanin; however it is the amount of polyphenol-oxidase found in each cell and time that reflects the production and color change of melanin. The production and color change of melanin would guide us to determine the rate of the enzymatic activity. The higher amount of melanin being produce will result darker colors, which will lead to higher absorbance, which shows faster enzymatic rate. In addition, polyphenol-oxidase acts as an oxidase that can catalyze the oxidation by binding with molecular oxygen to form OH group. (Samisch 1935) When polyphenol-oxidase is exposed to oxygen, it will immediately catalyze the oxygen to speed up reactions with substrate to produce melanin. In this procedure we also assumed that the substrate in our solution is in excess. Since there is an excess substrate concentration, all the active sites of the enzyme will become occupied with substrate, resulting for the enzyme to become saturated with substrate and the velocity of the chemical reaction has reach its maximal rate, also known as
Data from Table 1. confirms the theory that as the concentration of glucose increases so will the absorbance of the solution when examined with the glucose oxidase/horseradish peroxidase assay. Glucose within the context of this assay is determined by the amount of ferricyanide, determined by absornace, which is produced in a one to one ratio.1 Furthermore when examining the glucose standards, a linear calibration curve was able to be produced (shown as Figure 1). Noted the R2 value of the y = 1.808x - 0.0125 trend line is 0.9958, which is statistically considered linear. From this calibration curve the absorbance values of unknowns samples can be compared, and the correlated glucose concentration can then be approximated.
In the lab, Inhibiting the Action of Catechol Oxidase we had to investigate what type of enzyme inhibition occurs when an inhibitor is added. Catechol oxidase is an enzyme in plants that creates benzoquinone.Benzoquinone is a substance that is toxic to bacteria. It is brown and is the reason fruit turns brown. Now, there are two types of inhibitors, the competitive inhibitor and non-competitive inhibitor. For an enzyme reaction to occur a substrate has to bind or fit into the active site of the enzyme. In competitive inhibition there is a substrate and an inhibitor present, both compete to bind to the active site. If the competitive inhibitor binds to the active site it stops the reaction. A noncompetitive inhibitor binds to another region
Table 6 shows the results of the biochemical tests. The isolate can obtain its energy by means of aerobic respiration but not fermentation. In the Oxidation-Fermentation test, a yellow color change was produced only under both aerobic conditions, indicating that the EI can oxidize glucose to produce acidic products. In addition to glucose, the EI can also utilize lactose and sucrose, and this deduction is based on the fact that the color of the test medium broth changed to yellow in all three Phenol Red Broth tests. These results are further supported by the results of the Triple Sugar Iron Agar test. Although the EI does perform fermentation of these three carbohydrates, it appears that this bacterium cannot perform mixed acid fermentation nor 2,3-butanediol fermentation due to the lack of color change in Methyl Red and Vogues-Proskauer
Living organisms undergo chemical reactions with the help of unique proteins known as enzymes. Enzymes significantly assist in these processes by accelerating the rate of reaction in order to maintain life in the organism. Without enzymes, an organism would not be able to survive as long, because its chemical reactions would be too slow to prolong life. The properties and functions of enzymes during chemical reactions can help analyze the activity of the specific enzyme catalase, which can be found in bovine liver and yeast. Our hypothesis regarding enzyme activity is that the aspects of biology and environmental factors contribute to the different enzyme activities between bovine liver and yeast.
Is there a difference in the rate of reaction of catalase activity between pinto beans and carrots? Based on our research, we believe that the catalase activity in pinto beans will increase more relative to the catalase activity in whole carrots because pinto beans are higher in protein. We conducted an experiment to test our hypothesis that if we increase the hydrogen peroxide concentration then we will see higher kinetic saturation in pinto beans over whole
The purpose of this experiment was to see if phenylthiourea (PTU) is a non-competitive or competitive inhibitor. Catechol, a phenolic compound found in the potato extract used will play the part of the substrate. Competitive inhibitors are known to bind to the active site of an enzyme and mimic the job of a substrate. This in turn causes the substrate to compete for a position at the active site and increase the concentration of substrate but the inhibitor is still at a constant level. If PTU were a competitive inhibitor the test tube carrying the extract would turn dark brown. Non- competitive inhibitors are known to bind on the enzyme and prevent the substrate from attaching
In this work, the mechanical and barrier properties were examined for Polypropylene (PP) film in which the surface of the film was modified by Oxygen plasma treatment. The PP film was treated in various intervals of time of 60 s, 120 s, 180 s, 240 s and 300 s with three various RF power settings of 7.2 W, 10.2 W, 29.6 W. The contact angle was measured to characterize the wettability. The oxygen functional groups were generated on the surface of oxygen modified PP which was observed by Fourier transform infrared spectroscope and it was resulted in the improvement of wettability. The surface morphology and roughness of the PP films before and after the oxygen plasma treatment was analyzed by Atomic Force Microscopy (AFM). It was found that the roughness of
Enzymes are a catalysts that speed up a chemical reaction inside of a cell without being consumed or changed by the reaction. (Wright, W. 2015) Enzymes catalyse reactions by lowering the activation energy that is required for the reaction to occur. (Nature, 2012) In this experiment we will be using Succinate dehydrogenase which is an enzyme that has been extracted from chicken hearts, succinate dehydrogenase is an enzyme of the TCA cycle (citric acid cycle) and involves the catalyses the oxidation of succinate, this means there is a loss of 2 hydrogen atoms. The aims of this experiment are to use 6-dichlorophenolindophenol (DPIP) as a hydrogen acceptor. When DPIP is blue it is in a oxidised state, but when it accepts 2 hydrogen atoms it will become colourless, the disappearing of colour indicates that a reaction is occurring. After the colour is gone we use the time taken to work out the rate of the reaction. in this experiment we will
The independent variable for this experiment is the enzyme concentration, and the range chosen is from 1% to 5% with the measurements of 1, 2, 4, and 5%. The dependant variable to be measured is the absorbance of the absorbance of the solution within a colorimeter, Equipments: Iodine solution: used to test for present of starch - Amylase solution - 1% starch solution - 1 pipette - 3 syringes - 8 test tubes – Stop clock - Water bath at 37oc - Distilled water- colorimeter Method: = == ==
With this information we were able to identify any patterns and similarities. Hypothesis: The higher the temperature of water, potato and H²O², the rate at which the Enzyme will work will be faster therefore producing more oxygen. The reaction will be the same without the catalase (potato). Therefore in both experiments the Enzyme will work more rapidly and produce more oxygen. Aim: To test the hypothesis.
Enzyme peroxidase is essential in any cell metabolic reaction as it breaks down the harmful hydrogen peroxide to harmful products in the body. The report analyzed its effect on changes in temperatures by determining the optimum temperatures and the effects of its reversibility. Through the method of extracting the enzyme by blending it with potato tissue in phosphate buffer, the effects were analyzed on the effect of the dye guaiacol and the activity measured under different temperatures. The optimum temperature was obtained at 22.20C and above this temperature, the enzyme was denatured. Conclusively, increase in temperature increases
Despite of general properties of enzymes, the properties also varies from where it comes from and how it been produced. For instance, the enzymatic saccharification method in lignocellulosic bioethanol is generated by hydrolyzing cellulose and hemicelluloses. This method gets high attention because of its higher theoretical yield compared to other methods (Taneda et al., 2012). Acremonium cellulolyticus with high activities of cellulase, amylase and pectinase enzymes allow it for the easy separation of solids/liquids in potato pulp, resulting in high saccharification efficiency and a high recovery rate of products (Gao et al., 2014). On the other hand, Enzyme-modified carboxymethyl starch (ECMS) is beneficial in enhancing water holding capacity, emulsion stability and improving sensory characteristics of sausages with a declined fat content (Luo and Xu, 2011). Lipases and phospholipases of dormant cotton seeds have stability in heat, various media and nature of the hydrolysis of the lipids properties (Rakhi...
This report will illustrate the enzymatic action of the enzyme catecholase, which is common in plants. To study this particular enzyme in a laboratory, the natural substrate catechol is oxidized by the removal of two hydrogen atoms. The substrates of the enzyme are catechol and oxygen. These substates react with one another within the active site of the enzyme. The products formed by this reaction are benzoquinone has a brown color, you can see that the reaction has taken place. This is called the fruit browning reaction. Benzoquinone inhibits the growth of microorganisms and prevents damaged fruit from rotting. In undamaged cells catecholase is stored in vesicles and does not interact with catechol.
Boucherit et al. (2013) used Cucurbita pepo (courgette) peroxidase to decolorize Direct Yellow (DY106) and azo dyes. They also noticed the effect of temperature, pH, concentration of H2O2 and enzyme on degradation. The decolourization of DY106 was verified by UV-Vis analysis.
It changes from blue to red with acids but loses its colour in the presence of certain chemicals, one of which is vitamin C. DCPIP solution can be used to test for the presence of vitamin C in foods. Hypothesis Orange juice has the highest content of vitamin C. Citrus fruits have a higher content of vitamin C. The orange and lemon juice contain more vitamin C than the pineapple juice. Furthermore, as lemons are more acidic than oranges, I predict that the orange juice will contain more vitamin C than the lemon juice. Vitamin C affects, the ph the more vitamin C the higher the ph. Variables Independent Variables Different fruit juices (Pineapple, orange and lemon).