Friday, October 24, 2014

pH Effects on Enzym Activation

CHAPTER I
INTRODUCTION
A.    Background
Inside the body of life creatures, chemistry reaction was happened. Reactions which were happening in their bodies happen in temperature 27 oC (room temperature), for example on plant bodies. Beside that, it also can happen in teperature of 39 oC, for example inside the body of awarm blood animal. In that temperature , oxidation process will be happen slowly
or even doesn’t happen. So that the reaction will be happen faster we need catalysator for it. Catalysator is a subtance which can make the reaction work faster than before without join on that reactions. Catalysator inside the cells of life creature is called biocatalysator or we know that as enzyme.
Because of enzyme’s function is to make the reaction more faster and it doesn’t join to the reaction, so the amount is not too much. One molecule of enzyme can work many times during the enzyme was not damaged. Working of an enzyme was influenced by some factors, that temperature, pH,product, and inhyibitor. For knowing how far the factors influence the work of enzyme, where we took pH to observed, so we did this experiment to know about the factors which influence the work of enzyme.
A chemistry reaction, especially between organic compound, which do in laboratory need a condition which is determined by some factors which are temperature, pressure, time, and so on. When one of  the condition is not comfort with what should we need so the reaction doesn’t work well. Our bodies is a complicated laboratory, because in that body happen various chemistry reaction. Decomposition of subtances there are in our food, use result of description to get energi, Penguraian zat-zat yang terdapat dalam makanan kita, penggunaan hasil uraian untuk memperoleh energi, affiliation return result of description to form the food supply in body and also a lot of kinds of other reaction which is if done in laboratory or in vitro require the specialty and also time old ones, can take place better in body or in vivo not requiring high temperature and can be happened during which relative shorten. React or chemical process that goes on better in our body this enabled [by] caused by [his/its] [is] katalis of[is so-called enzyme. Chemical process that happened by force of enzyme have been recognized [by] since former epoch for example out of job making by ferment or fermentation. Pursuant to that m atter, praktikan will [do/conduct] this praktikum with the title of praktikum of influence pH to enzyme activity to know the influence pH to aktifitas enzyme by manipulation of pH amilum with the addition HCL, NaOH, and also Fehling A and Fehling B.
B.     Purpose
To prove the effect of pH on amylase enzyme activity.
C.    Benefits
The student can prove the effect of pH on amylase enzyme activity.












CHAPTER II
PREVIEW OF LITERATURE
Enzymes can be found both in animals and in plant. At an enzymes found in plants is amylase. Another name of aylase is Diastase. Enzymes can hydrolyze starch into sugar. Amylase produced by the leaves ore seeds are germinating. Amylase activity is affected by inorganic salts, pH, temperature, and light. The optimum pH of amylase according to Hopkins, Cole, and Green (Miller,1938) is 4,5 to 4,7         (Team Lecturer,2012).
For every enzyme, there is an optimum pH value at which the specific enzyme functions most actively. Any change in this pH significantly affects the enzyme activity and/or the rate of reaction. To know more about the relation between pH and enzymes and/or pH effect on enzymes, read on (Ningthoujam Sandhyaran, 2011).
http://www.buzzle.com/img/articleImages/334132-918-3.jpg
Enzymes are proteinaceous catalysts, which speed up the rate of a biochemical reaction. They reduce the activation energy that is essential for starting any type of chemical reaction. With a low energy requirement for activation, the reaction takes place faster. The overall performance of an enzyme depends on various factors, such as temperature, pH, cofactors, activators and inhibitors. You might have a fair idea regarding pH effect on enzymes. But, why and how does pH and temperature affect enzymes? This article highlights on the enzyme activity with reference to change in the pH level.The rate of a chemical reaction and/or the enzyme activity is greatly influenced by the structure of the enzyme. Or in other words, a change in the structure of the enzyme affects the rate of reaction. When pH of a particular medium changes, it leads to alteration in the shape of the enzyme. Not only on enzymes, the pH level may also affect the charge properties and shape of the substrate. Within a narrow pH range, changes in the structural shapes of the enzymes and substrates may be reversible. But for a significant change in pH levels, the enzyme and the substrate may undergo denaturation. In such cases, they cannot identify each other. Consequently, there will be no reaction as such. This the reason why, pH affect enzyme activity.Speaking about the connection between pH and enzymes and/or pH effect on enzymes, each and every enzyme is characterized by an optimum pH. At this specific pH level, a particular enzyme catalyzes the reaction at the fastest rate than in any other pH level (Ningthoujam Sandhyaran,2011).
 For example, the enzyme pepsin (a protease enzyme) that catalyzes proteins is most active at an acidic pH, whereas the enzyme trypsin (another protease enzyme) performs best at a slightly alkaline pH. Thus, the optimum pH of an enzyme is different from that of another enzyme.When we study pH, it is clearly defined as the measurement for the acidic or alkaline nature of a solution. To be more precise, pH indicates the concentration of dissolved hydrogen ions (H+) in the particular solution. An increase or decrease in the pH changes the ion concentration in the solution. These ions alter the structure of the enzymes and at times, the substrate either due to formation of additional bonds or breakage of already existing bonds. Ultimately, the chemical makeup of the enzyme and substrate are changed. Also, the active site of the enzyme is changed, after which the substrate can no longer identify the enzyme. For more information on enzymes, you can refer to enzyme substrate complex.Consider a case, when the reaction is adjusted at a pH level different from the optimum value. Over here, the rate of reaction or the activity of enzymes will not be the same as the previous one. At times, you will notice that there is no reaction at all. This occurs, when there is changes in the structure of the active site and the substrate. Hence, for the chemical reaction to take place, you need to adjust the pH of the solution in such a way that it is suitable for both the enzyme and the substrate. This way, pH effect on enzymes activity can be studied practically (Ningthoujam Sandhyaran, 2011).
pH is a measure of the concentration of hydrogen ions in a solution.
The higher the hydrogen ion concentration, the lower the pH. Most  enzymes function efficiently over a narrow pH range. A change in pH  above or below this range reduces the rate of enzyme reaction  considerably. Changes in pH lead to the
breaking of the ionic bonds that hold the  tertiary structure of the enzyme in place. The enzyme begins to lose  its functional shape, particularly the shape of the active site, such  that the substrate will no longer fit into it, the enzyme is said to  be denatured. Also changes in pH affect the charges on the amino acids within the active site such that the enzyme will not be able to form  an enzyme-substrate complex. The pH at which an enzyme catalyses a reaction at the maximum rate is called the optimum pH. This can vary considerably from pH 2 for pepsin to pH 9 for pancreatic lipase (Anonymous, 2012).
All biological systems are based on the same organic molecules, a similarity that is one of many legacies of life’s common origin. However, the details of those molecules differ among organisms. Simple organic building blocks bonded in different numbers and arrangements form different versions of the molecules of life, just as atoms bonded in different numbers and arrangements form different molecules. Cells maintain reserves of small organic molecules that they can assemble into complex carbohydrates, lipids, proteins, and nucleic acids. When used as subunits of larger molecules, the small organic molecules (simple sugars, fatty acids, amino acids, and nucleotides) are called monomers. Molecules that consist of multiple monomers are called polymers. Cells build polymers from monomers, and break down polymers to release monomers (Starr,2011).
 Metabolism refers to activities by which cells acquire and use energy as they make and break apart organic compounds. These activities help cells stay alive, grow, and reproduce. Metabolism also requires enzymes, which are organic molecules that speed up reactions without being changed by them (Starr,2011).
“Saccharide” is from sacchar, a Greek word that means sugar.Monosaccharides (one sugar unit) are the simplest type of carbohydrate, but they have extremely important roles as components of larger molecules. Common monosaccharides have a backbone of five or six carbon atoms, one carbonyl group, and two or more hydroxyl groups. Enzymes can easily break the bonds of monosaccharides to release energy . The solubility of these molecules also means that they move easily throughout the water-based internal environments of all organisms. Monosaccharides that are components of the nucleic acids DNA and RNA have five carbon atoms. Glucose (at left) has six. Glucose can be used as a fuel to drive cellular
processes, or as a structural material to build larger molecules. It can also be used as a precursor, or parent molecule, that is remodeled into other molecules. For example, cells of plants and many animals make vitamin C from glucose (human cells cannot, so we need to get our vitamin C from food). Cellulose does not dissolve in water, and it is not easily broken down. Some bacteria and fungi make enzymes that break it apart into its component sugars, but humans and other mammals do not. When we talk about dietary fiber, or “roughage,” we are usually referring to the cellulose and other indigestible polysaccharides in our vegetable foods. Bacteria that live in the gut of termites and grazers such as cattle and sheep help these animals digest the cellulose in plants (Starr,2011).
            All living things are chemical factories driven by chemical reactions. However, these chemical reactions proceed very slowly when carried out in the laboratory because the activation energy is high. To be useful to living organisms, additional substances must be present where the chemical reactions occur to reduce the activation energy and allow the reaction to proceed quickly. A catalyst is a substance that lowers the activation energy needed to start a chemical reaction. Although a catalyst is important in speeding up a chemical reaction, it does not increase how much product is madeand it does not get  used up in the reaction (Biggs,2008).
In our overview of food processing, we have seen that digestive enzymes hydrolyze the same biological materials (such as proteins, fats, and carbohydrates) that make up the bodies of the animals themselves. How, then, are animals able to digest food without digesting their own cells and tissues? The evolutionary adaptation found across a wide range of animal species is the processing of food within specialized compartments. Such compartments can be intracellular, in the form of food vacuoles, or extracellular, as in digestive organs and systems. Ingestion and the initial steps of digestion occur in the mouth, or oral cavity. Mechanical digestion beginsas teeth of various shapes cut. smash, and grind food. making the food easier to
swallow and increasing its surface area. Meanwhile, the presence of food stimulates a nervous reflex that causes the            salivary glands to deliver saliva through ducts to theoraJ cavity. Saliva may also be released before food enters the mouth, triggered by a learned association between eating and the time of day, a cooking odor, or another stimulus. Saliva initiates chemical digestion while also protecting the oral cavity. Amylase. an enzyme in saliva, hydrolyzes starch (a glucose polymer from plants) and glycogen (a glucose polymer from animals) into smaller polysaccharides and the disaccharide maltose. Mucin, a slippery glycoprotein (carbohydrateprotein complex) in saliva. protects the lining of the mouth from abrasion. Mucin also lubricates food for easier swallowing. Additional components of saliva include buffers, which help prevent tooth decay by neutralizing acid, and antibacterial agents, which protect against microorganisms that enter the mouth with food (Campbell,2008).




CHAPTER III
PRACTICUM METHOD
A.    Time and Place
Day / Date            : Friday / December 7th 2012
Time                     : at 08.10 - 09.10 am
Place                      : Laboratory of Biology at 3rd floor of BiologyDepartement of Science and Mathematic Faculty, State University of Makassar
B.     Tools and Materials
1.      Tool
a.       Centrifuge and centrifuge tubes
b.      10 test tubes
c.       Pipette
d.      Small Funnel
e.       Test tube rack
f.       Lights spiritus
g.      pH Paper / pH meter
2.      Material
a.       Sprout of Green Bean
b.      Starch solution
c.       Fehling Solution A and B
d.      Dilute HCl (10%)
e.       1% NaOH solution
f.       Aquades
C.    Work Procedure
1.      Took sprout of green bean and put it on the 10 tubes.Entered sprouts extract obtained into the tube I, checked and recorded the pH. Furthermore, the liquid into 3 tiny tubes, labeled a, b, c. After 10 minutes, added or Fehling solution A and B into a tube. After 15 minutes, added the same subtances in the tube c. Recorded the color. Then heated all of the tubes in the time.
2.      In the second tube added drops of NaOH solution, pH checked and recorded. Further treatment such as no. 1.
3.      In the third tube added 1 drop of dilute HCl, checked and recorded the pH. Further treatment such as no. 1.
4.      In the IV tube added Fehling A and B and note the color.
5.      Compared the color that occurs on the tubes, created a table and concluded.






















CHAPTER IV
 RESULT AND DISCUSSION
A.    Result
1.      Observation Table
Nu. Tube
pH
Change
Before Heating
After Heating
I
6
a.White
a.White greenly
b.White
b.Yellowish green
c.White
c.Yellow greenness
II
12
a.Yellowish green
a.Golden yellow
b.Yellowish green
b.Old green
c.Yellowish green
c.Brown yellow
III
1
a.White
a.Transparent
b.White
b.White Blue
c.White
c.White
IV

White
Yellowish green

2.      Observation Tubes
a)      Before Heated
 










                                                                                                                     

 





 








b)      After Heated
 




















B.     Discussion
In the 1st tube was added with sprouts extracts and the pH of it is 6, after that it is added again with amilum and fehling A and B after 5 minutes the color is white. Actually this tube is divided to be 3 tube and those are given same material but the different is the time when enter the material. But they have same color so we just take one tube to be observer. This tube is warmed three times. For the first warm, after 5 minutes the color change from white to be white  greenly. And then it was warmed again and after 10 minutes the color become white to yellowish green, like that also the color for the third warm. It change from white to yellow greenness. The change of the color happened because the lateness have sour and alkali characteristic.
We also have done the same with the first tube, in the 2nd tube is added also with sprouts extracts, amilum and fehling A and B. but this tube was given also with NaOH solution lateness. And when the pH is measured, it had pH =12, and the color was yellowish green. This tube was warmed three times too, for the first warm after 5 minutes the color change from yellowish green be golden yellow, for the second warm the color be old green, and the third warm the color yellow brown. This happened because the lateness had sour and alkali characteristic. And it same meaning if there was  enzim that gave influence to the amilum.
For the 3rd tube is same with the first and the second tube, it was added with sprouts extracts, amilum and fehling A and B, the different was this tube HCl lateness. The color is white and its pH is 1. This tube was given three times warm also. When the first warm after 5 minutes the color was change  from white be tansparent, then for the second warm after 5 minutes the color be white blue, the third warm the color is still white. So, there was enzyme that gave influence for amilum, so that the amilum be change.
In the 4th tube was added also with sprouts extracts, amilum and fehling A and B. The color was white, after 5 minutes and warmed until the practicum had finished the color become yellowish green. This happen because there was not enzyme that gave influence for the amilum to be glucose.




















CHAPTER V
CONCLUSION AND SUGGESTION
A.    Conclussion
Based on experiment, we have known that pH has an influences for enzymes activities. Enzyme will work on optimal pH, such as enzyme amylase work in pH between 4,5 – 4,7. The change of color is mean that the enzyme is working although the color is not comfort with the theory and the enzyme doesn’t work optimal.
B.     Suggestion
1.      Laboratory should prepare well the tools which will be used in experiment.
2.      In doing an experiment we must be careful when use the tools to avoid the accident which probably will happen. We must observe the object carefully and seriously so that we can find a good result.
3.      The assistant should give command so we can miss the mistake while doing the experiment.




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 BIBLIOGRAPHY
Anonymous. 2012. The Effect of pH on Enzyme Activity. http://www.123helpme.com.
Accessed on December 8th  2012
Sandhyarani Ningthoujam . 2011. pH Effect on Enzymes. http://www.buzzle.com. Accessed on December 8th  2012
Biggs, at. el. 2008. Biology.United States of America: Glencoe.
Campbell, at. el. 2009. Biology. San Francisco: Benjamin Commings.
Starr, at. el. 2011. Biology. Canada: Cengange

Team Lecturer. 2012.  Basic Biology Guide Book. Makassar: Biology Departement Faculty of Mathematic and Science, State University of Makassar.

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