Effects of pH and Temperature on Enzymes Reaction in Foods Containing Starch

Effects of pH and Temperature on Enzymes Reaction in Foods Containing Starch

Introduction

Enzymes are described as proteins that act as catalytic agents (Brooker, Widmaier, Graham & Stiling, 2011). Similar to most proteins, enzymes are synthesized by the cell’s ribosomes. They react with certain substrate to enhance the level of the cell’s chemical reaction. Reactions would be much slower without enzymes and organisms would not be able to perform the most basic functions, like digesting food or breathing.

Amylase is a variety of enzyme, which has a dynamic site grouped in subsites, whereby each houses a residue of glucose (Talamond, Noirot & de Kochko, 2005). It breaks down starch to glucose, enabling food to have a sweet taste. Sweet potatoes are an example of an amylase in the natural world.  When they are not ready for harvesting, the amylase has not yet broken down the starch, however, by the time they are harvested, the reaction has been finished thus giving the sweet potatoes that distinctive sweet taste. To that extent, through the use of a sweet potato, the objective of this experiment was to test how the enzyme concertation, pH level, and temperature transformed the effectiveness of amylase. 

Methodology

            The first step was to perform an indicator test. A one-millimeter (ml) sample of starch solution was put into tow test tubes through the use of a pipette. The same process was done with one ml of maltose. 5 droplets of I₂KI compound were added into one of the test tubes containing starch and one with maltose. Then Benedict’s reagent was added into the other test tubes of starch and maltose. The test tubes containing Benedict’s reagent were rested in a heated sand bath. The four tubes were then observed for color change, which indicates a reaction.

The activity of amylase was then watched through three mixtures of reaction. The first mixture was a starch solution of one ml and an amylase solution of one microliter (µL). the second featured starch of one ml and water (50 µL). The third and last was amylase (50 µL) and one ml of water. Instantly, a droplet of each solution was transferred to a discreet well placed on a spot plate and a droplet of I₂KI was infused. This was done repeatedly after every 60 seconds. The color was watched as time passed to infer whether the activity of amylase was present or not. Five droplets of benedict’s reagent were added to the three test tubes after eight minutes before they were placed in a heated sand bath. The tubes were watched for color change, showing the presence of maltose.

The impact of temperature was watched through the three water baths set to 37 degrees Celsius (°C), 23°C, and 4°C; a starch solution of pH 7 rested on all the three water baths. An amylase solution (50 µL), was put into a test tube through a pipette and then placed in a water bath for 60 seconds. Following this, one ml of the temperature balanced starch was infused. Instantly, a droplet of the reaction was moved to the plate and one droplet of I₂KI was infused. This process was repeated after ever sixty seconds to examine the presence of starch. The process was done for all the three temperatures. Eventually, five droplets of Benedicts reagent were infused and the test tubes were put in a heated sand bath.

Following this, the pH levels were examined. Starch solutions of pH 4,5,6, and 7 were filled four test tubes in that respective order. Then, amylase (50 µL) was added to the test tubes, and instantly, one droplet of each solution was moved to the spot plate and a droplet of I₂KI was infused. The process was repeated at intervals of 60 seconds. Five droplets of benedict’s reagent were added to the three test tubes after eight minutes before they were placed in a heated sand bath. Lastly, the impact of enzyme concertation was examined. A starch solution (one ml) of pH 7 was put into the three test tubes through a pipette. In one test tube 5% enzyme (50 µL), whilst a 10% enzyme and 20% enzyme of the same quantity were added to the other tubes. One droplet of each solution was instantly moved to the spot plate and a droplet of I₂KI was infused; this was repeated every 60 seconds. Five droplets of benedict’s reagent were added to the three test tubes after eight minutes before they were placed in a heated sand bath.

The Results of The Experiment

Within the signs of the experiment, the first test tube transformed from a clear solution to dark purple. The second tube shifted to yellow from blue while the third and the fourth tube did not exhibit any color changes.

In regards to the amylase experiment, the first tube showed starch within the initial test but did not thereafter. the second tube showed starch for the entire eight minutes. The third tube never showed starch. Only the first tube demonstrated any color change after being exposed to heat and Benedict’s reagent, providing evidence of the presence of maltose.

Temperature appeared to have a positive correlation with the rate of reaction. The fastest reaction occurred at the temperature 37°C as illustrated in Graph 1. Maltose was demonstrated to be present in each of the three test tubes.

Graph 1: The Impact of temperature on the Activity of an Enzyme

The connection with pH does not appear clearly. Test tubes two and three, which hard starch of pH 5 and 6, finished the reaction simultaneously. Graph 2 illustrates the rate of reaction of the different level of pH. Maltose was present in each of the test tubes.

Graph 2: The Impact of pH on the Activity of an Enzyme

The reaction time reduced as the amylase got increasingly concentrated. Graph 3 illustrates the direct association. Each of the three test tubes had a presence of maltose.

Graph 3: The Impact of Enzyme Concertation on Activity 

Discussion of Results

In the indicator test, it was fundamental to examine what each indicator embodied. This enabled the utilization of I₂KI to show starch and use of Benedict’s reagent to show maltose. The amylase activity /control illustrated that is important for both amylase and starch to be mixed to enable the reaction to happen. As anticipated, upon the increase of temperature, the rate of reaction also increased. This is anticipated since this reaction typically happens in the human body where the usual temperature is 37°C (Van Der Maarel et al., 2007). The findings of the pH did not plainly illustrate what the best enzyme level was. The concertation test was much clearer. The 20% concertation reacted more rapidly since there were more enzymes to react with the substrate and develop maltose.

References

Brooker, R.J., Widmaier, P., Graham, L., &. Stiling, P. (2011). Biology. 2nd ed. New York: McGraw Hill.

Talamond, P, Noirot M, & De Kochko, A. (2005). “The Mechanism of Action ofα-amylase from Lactobacillus Fermentum on Maltooligosaccharides.” Journal of Chromatography B :42-47. Science Direct. Web

Van Der Maarel, M. J., Van der Veen, B., Uitdehaag, J. C., Leemhuis, H., & Dijkhuizen, L. (2002). Properties and applications of starch-converting enzymes of the α-amylase family. Journal of biotechnology, 94(2), 137-155.