In recent years, the biotechnological use of xylans and xylanases has grown remarkably (Aristidou and Pentillä 2000; Subramaniyan and Prema 2002; Beg et al., 2001; Techapun et al., 2003). The end-products of xylan degradation of considerable importance in commercial applications are furfural and xylitol (Parajó et al., 1998). Xylan can be converted to β-D-xylopyranosyl and its oligosaccharides via two types of hydrolysis: acid or enzymatic. Acid hydrolysis is often preferred because it is faster, but it is accompanied by the formation of toxic compounds that may hinder subsequent microbial fermentation. Furthermore, in the long run, it can lead to corrosion of the metallic equipment that comes in contact with the acid. Recently, some industrial companies have shown interest in the development of efficient enzymatic processes to be used instead of acid hydrolysis in the treatment of material containing hemicellulose. Commercial xylanases are industrially produced, for example, in Japan, Finland, Germany, Republic of Ireland, Denmark, Canada and the USA. The microorganisms used to obtain these enzymes are Aspergillus niger, Trichoderma sp. and Humicola insolens. Nevertheless, commercial xylanases can also be obtained from bacteria. Xylanase began to be used in the 1980s: initially in the preparation of animal feed and later in the food, textile and paper industries. Currently, xylanase and cellulase, together with pectinases, account for 20% of the world enzyme market.
1.10.1
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
Yeast is a fungus that can generate glucose into energy without using any oxygen molecules. We tested the fermenting ability of yeast from two different carbon sources: glucose and aspartame. We hypothesized that yeast is unable to use the carbon sources of aspartame. To do this, we decided to use both carbon sources in the same concentration. Each carbon source was mixed with the same amount of yeast solution. The experiment group of 5.5 mM aspartame solution was compared with the control group of 5.5mM glucose solution. We recorded the rate of fermentation for glucose and aspartame in the Vernier Lab Quest. The fermentation rate of aspartame is a negative number, and glucose is a positive number. Our results show that yeast was unable to ferment aspartame as yeast fermented glucose. The results indicate that aspartame has no effect on yeast fermentation rate because yeast do not catabolize aspartame because it does not have the appropriate enzymes to break it down.
The optimal temperature of Bacillus lichenformis bacterial amylase and Aspergillus oryzae fungal is determined by mixing a starch solution into the bacterial and fungal amylases that are put in four different temperatures (0, 20, 55, 85 degrees Celsius). Then after every two-minutes, ending at the ten-minute mark, a small sample of the starch-amylase mixture is put into a well with a couple drops of iodine to help show the change in starch. This was done because when iodine is exposed to starch it changes color. Based on the color chart given in our lab manuals, the reaction of the amylase to the starch solution will give the starch-amylase mixture in the iodine a yellow color to signify if the presence of solely iodine and/or little starch depending on temperature. This means that the amylase broke down the starch solution because its temperature was optimal. Majority of the results came out black or dark brown therefore the amylase wasn’t put in the proper temperature to break down the starch solution at a faster pace. The temperature that seemed most optimal was at 55 degrees Celsius for both fungal and bacterial because it showed a more brown to yellowish color when put into the iodine. That showed that the amylase was able to break down the starch at a faster rate because it was working at its optimal temperature.
Moreover, CtXynGH30 also displayed activity against the polysaccharides having xylan main chain decorated with arabinose side chains such as arabinoxylans. Therefore a range of substrates showing the enzyme activities were treated with CtXynGH30 and the hydrolysed products were analyzed by TLC. The results showed that the enzyme is active against different polysaccharides and produces a series of oligosaccharides. The enzyme is active on xylan main chain polysaccharide substrates like beechwood-, birchwood- and 4-O-methyl glucurono-xylan and capable of releasing oligosaccharides such as xylose, xylobiose and other higher neutral and acidic oligosaccharides (Lane 1-3, Fig. 5). CtXynGH30 also acted over substrates having xylan main chain decorated with various degrees of arabinose side chains like oat spelt xylan, wheat arabinoxylan and rye arabinoxylan and producing xylobiose, xylotriose and other higher oligosaccharides (Lane 4-6, Fig. 5). Furthermore, the TLC profile of CtXynGH30 showed hydrolysis of arabinogalactan and more likely the release of arabino- oligosaccharides (Lane 7, Fig. 5), whereas, arabinan (sugar beet) and xyloglucan did not release any hydrolysed product (Lane 8-9, Fig. 5). The ability of CtXynGH30 to hydrolyse arabinoxylans apart from glucuronoxylans
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,
An enzyme also known as a protein, is a biological catalyst which speeds up chemical reactions by lowering the activation energy to increase the rate in which the reaction occurs. The enzyme used was amylase, which breaks down starch molecules into maltose. PH, substrate concentration, salt concentration, and temperature. When enzymes reach a low temperature, the activity is slowed down of molecule movement, but the enzyme is not destroyed. Once enzymes are placed in optimal temperatures once again, it will restore its activity to a normal rate. When enzymes reach too high above optimal temperature, the enzyme is denatured and cannot be restored. In the experiment performed the activity of breaking down starch in fungal and bacterial amylase was being tested at a range of temperatures and time. The fungal and bacterial amylase work best at optimal temperature. Amylase will function best at sixty degrees Celsius at 10 minutes when starch had been one hundred percent hydrolyzed. Hydrolyzed is the breakdown of molecules through addition of water. The experiments independent variables were the time, temperature and enzyme used. The dependent variable was the enzyme activity that broke down the starch into maltose. The controlled variables were the temperature baths, the iodine drop amount, the mixture drop amount, and location of experiment. The control group was the zero minutes without amylase at
Hydrolysis of starch for fungal amylase Aspergillus Oryzae and bacterial amylase Bacillus Licheniformis at different temperatures.
This laboratory experiment was carried out to establish the optimal temperature for bacterial and fungal. Besides, it will evaluate the effect of temperature on the ability of amylase to break down starch maltose. Collect 4 test tubes for each of the amylases. The test tubes were then labeled with their matching temperatures. 5ml of the 1.5% starch was added into half of each of the test tubes. Thereafter, each of the test tubes is placed into the corresponding temperatures. An Iodine test was carried out to observe the starch hydrolysis process. The two spot plates were established for fungal
This experiment consisted of setting up a control group of starch in various temperature and then placing both fungal amylases and bacterial amylases in a mixture of starch and placing the solution of amylase and starch in various temperatures of water. After a certain amount of time- different amount of time needs to be used in order to have reliable results- iodine is added in a well on spot plates, then two drops of the mixture of amylase-starch is added from each temperature used, by adding iodine into the plates the mixture will show how much starch was hydrolyzed, this is used to calculate the amount of
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 effects of temperature on fungal amylase Aspergillus oryzae, and bacterial amylase, Bacillus licheniformis ability to break down starch into maltose was studied. The study determined the optimal temperature the Aspergillus oryzae and Bacillus licheniformis was able to break down the fastest. The starch catalysis was monitored by an Iodine test, a substance that turns blue-black in the presence of starch. Amylase catabolizes starch polymers into smaller subunits. Most organisms use the saccharide as a food source and to store energy (Lab Manual, 51). The test tubes were labeled with a different temperature (0°C, 25°C, 55°C, 85°C). Each test tube was placed in its respective water baths for five minutes. After the equilibration process, starch was placed in the first row of the first row of the spot plate. Iodine was then added to the row revealing a blue black color. The starch was then added to the amylase. After every two minute section a pipette was used to transfer the starch-amylase solution to place three drops of the solution into the spot plate row under the corresponding temperature. Iodine drops was placed in the row. Color changes were noted and recorded. The results showed Aspergillus oryzae was found to have an optimal temperature between 25°C and 55°C and Bacillus licheniformis was found to have an
The enzyme-catalyzed reactions can be affected by different factors and by studying these reactions, a better understanding of the functioning of organisms can be obtained. To obtain the best results, wheat-germ acid phosphatase was chosen for this investigation as it is stable in laboratory and estimation of its activity is simple and reliable. The results can be compared to other enzymes since the properties of acid phosphatase are representative in a qualitative manner of many enzymes. It also gives optimal catalysis at acidic pH values which can be created by adding pH 5.0 citrate buffer (Coordinators,
Xylella fastidiosa was found destroying olive trees in Spain last year and most recently was found in almond orchards in Andalusia. Xylella fastidiosa causes the infected plant to dry out and look as if they had been burned, leading this pathogen to be known as the “olive tree leprosy” and the “Ebola of olive trees.” Xylella fastidiosa was first found in Italy in 2013 and last year officials destroyed over 1 million olive trees in an attempt to stop the bacteria from spreading. Spain is known to produce half of the world’s olive oil and in June of this year found the pathogen in almond trees in Valencia, an olive- producing region. It is believed that Xylella fastidiosa originated in America, one strain was found in California and the southern
Combination of aspergillopeptidase A and Aspergillus acid carboxypeptidase was efficient in deodorizing and debittering soybean protein hydrolysates(Article 2009). Alcalase treated wheat gluten hydrolysates had less bitterness level and overall acceptability of the product increased(Koo et al. 2014).
The purpose of this lab report is to investigate the effect of substrate concentration on enzyme activity as tested with the enzyme catalase and the substrate hydrogen peroxide at several concentrations to produce oxygen. It was assumed that an increase in hydrogen peroxide concentration would decrease the amount of time the paper circle with the enzyme catalase present on it, sowing an increase in enzyme activity. Therefore it can be hypothesised that there would be an effect on catalase activity from the increase in hydrogen peroxide concentration measured in time for the paper circle to ride to the top of the solution.