Effects Of Factors Affecting The Beetroot

Published Date: 02 Nov 2017

Jekathjenani Ratnakumaran

Lab Group: W04, Tuesday 1-3:50 pm

Biology 2070H

Experiment Date: February 5th, 2013

Group members: Graham Hendren

Ifeoluwaleke Shabi

Megan Hopkins

The Effects of Factors Affecting the Beetroot (Beta vulgaris) Cell Membrane

Abstract:

Cell membrane plays many roles in cell functions such as cell barriers, cell supporters, cell communicators and provides cell shape. This study was conducted to test the effect of environmental conditions on the cell membrane using various treatments such as temperature and detergents. Beetroot (Beta vulgaris) was selected to test the conditions on the cell permeability and uniform sizes of beet pieces were treated with hot bath, cold bath, distilled water, and 10% SDS solutions. This study was tested and the hypothesis is that the detergents will affect the cell membrane and a higher percentage of pigment will be leaked into the solution. Three trials were tested with the time interval of 10 minutes and reaction changes were monitored. Based on the result, detergent had higher effect on the cell membrane than temperature. In trial 1, 45% transmission of pigment leakage in hot bath; 11% transmission of pigment leakage in 10% SDS solution; 97% in distilled water, in trial 2, 38% transmission of pigment leakage in hot and cold bath; 15% transmission of pigment leakage in 10% SDS solution; 98% in distilled water and in trial 3, 54% transmission of pigment leakage in cold bath; 47% transmission of pigment leakage in hot bath and 13% transmission of pigment leakage in 10% SDS solution; 96% in distilled water. The hypothesis, the factor detergent causes more damage in beetroot (Beta vulgaris) cell membrane and increases the pigment leakage was supported by observing the positive result based on the transmission percentage of pigment leakage in the solution. Pigment leakage in the solution was analyzed by using a spectrophotometer.

Introduction:

Plant cells have selectively permeable membrane that allows selective substances to penetrate into the cell. Cell membranes are consisting of lipid layer that are made up of phospholipids. These phospholipids are amphipathic in nature, which have phospholipids head and tail respectively. Phospholipids heads are hydrophilic (water loving) and tails are hydrophobic (water fearing) to the cell membrane. As phospholipids have these properties, they are function as cell barriers to protect the cell from any incoming substances, as proteins and carbohydrates for cell communication, arrange, and provide surface area for metabolic reactions. Cell membranes are function as supporters for the cell and maintain its shape (Regina.B, 2013). In comparison of animal and plant cell, both have many similarities and differences. Based on the variation, vacuoles are found mostly in plant cell. Vacuoles are larger in size and plant cell may contain many vacuoles. Two vacuoles are fused together to form a large vacuoles. Francis.M states in his article that vacuoles play a main role in controlling the cell volume, store intracellular substances and regulate the cytoplasmic ions and pH of the cell. In addition, article states that in plant cell, most of the cell pigments are located in the vacuoles (Francis.M, 1999). Moreover, there are many factors affecting the cell membrane permeability. Temperature and detergents (SDS solution) are the main factors which disrupt the cell membrane and causes the pigment to leaked out of the cell in the plants. This process is taken place by the diffusion where molecules move from higher concentration to lower concentration gradient (Biology Laboratory Manual, 2013)

This experiment was conducted to study the characteristic function of the cell membrane using plant cell, a beetroot (Beta vulgaris) cell. Beetroot cell has large cell membrane and vacuole, which consists of pigment called betacyanins (β-cyanins). Beet cell has a pigment called betalains (β-lains) which is classified into two pigments such as betaxanthin and betacyanin based on the molecular structure. β-cyanins pigment is appearing as red to violet in colour. It is aqueous in nature (water soluble) and absorbs in the range of 535-550 nm (Veronica.L.G et al, 2005). This experiment is to understand the cell membrane effects on the different environmental conditions. The effect of environmental conditions on cell membrane was tested by using beetroot cell and various treatments such as temperature and detergents. To analyze the concentration effect of pigment, betacyanin and membrane damage, spectrophotometer was used to measure the absorption of pigment colour. The hypothesis and prediction of this study were stated as follows,

Hypothesis: Beetroot cell membranes are selectively permeable. The factors detergent and temperature will cause higher percentage damage on the cell membrane and increases the pigment leakage (Beta cyanins).

Prediction: If the detergent and temperature damage the beet cell membrane, there will be higher percentage of pigment leakage and so, it has less transmission percentage (transmission of light) than distilled water.

Materials and Methods:

In this study, the experiment was carried out by using beetroot (Beta vulgaris). Beet was uniformly cut into several pieces with equal surface area. Each piece of beet cut was measured approximately 2mm long, 1mm wide, and 0.5mm thick in size. Three trials were taken and all three trials were measured at ten minutes intervals. The experimental procedure was carried out in room temperature. 10% of detergent (SDS solution), hot bath, cold bath, and distilled water at room temperature were taken in the different test tubes. One piece of beet was placed in each test tube and time was set up using stop clock. Absorbance of pigment leakage was measured by using spectrophotometer. To measure the absorbance, additional 4 mL of 10% SDS solution was added in each test tube sample. In order to get an accurate result, spectrophotometer test tube was filled completely. For each sample, pigment (β-cyanins) leakage was measured by observing the changes in transmission percentage. Lower transmission percentage will have higher pigment leakage.

Results:

Effect of environmental conditions

Spectroscopic absorbance of transmission percentage of pigment leakage in three samples are measured and based on the values, the following plots are drawn.

Trial 1:

Figure 1 represents the spectroscopic absorbance of transmission percentage pigment leakage for given samples such as 10% SDS solution, hot bath, cold bath and distilled water in Trial 1.

In the figure 1, transmission percentage of pigment leakage was higher in distilled water than other samples. Observations are monitored for each sample at 10 minutes time interval. In order to test the temperature effect on beet cell, firstly, beet piece was placed in the cold bath sample test tube. In ten minutes, solution was frozen; beet colour was remained red; clear division of white frozen & red beet dye was observed in the test tube. In 20 minutes, solution was remained frozen; red colour concentrated at the bottom of test tube; beet colour was remained red and colour was obtained dark around the beet. In 30 minutes, solution was remained frozen; pink colour was obtained at bottom of the test tube; dye concentrated around the beet and it was not evenly dispersed. In hot bath sample, a piece of beet was placed in the test tube and observations were monitored. In 10 minutes, beet was appeared red in colour; dye from beet piece was spread throughout the solution and pink color was obtained uniformly. In 20 minutes, dark reddish pink colour was obtained uniformly throughout the test tube; beet was remained at the bottom of the test tube and no dye was concentrated around it. In 10% SDS (detergent) sample, a piece of beet was placed in the test tube. In 10 minutes, dye concentrated at the bottom of the test tube and around the beet; dye was not spread and the colour was remained at the bottom of the test tube. In 20 minutes, no characteristic change was obtained. In 30 minutes, clear division of dye and solution was obtained; dye concentrated at the bottom of the test tube. Distilled water was used as controlled solution, for all three trials beet piece dye was slightly dispersed in the solution.

Trial 2:

Figure 2 represents the spectroscopic absorbance of transmission percentage of pigment leakage for given samples such as 10% SDS solution, hot bath, cold bath and distilled water in Trial 2.

Figure 2 indicates that spectroscopic absorbance of transmission percentage of pigment leakage for hot and cold bath are equal. Beet pieces were placed in each sample and the observations were recorded. In cold bath sample, at 10 minutes beet was remained frozen; Solution frozen; beet still red; dye is concentrated at the bottom of test tube and appeared around the beet; solution colour was not dispersed uniformly. In 20 minutes, solution was frozen; red color was obtained at the bottom of the test tube; not evenly dispersed. In 30 minutes, no characteristic change was obtained. In hot bath sample, in10 minutes, deep red colour was formed uniformly. In 20 minutes, bright red colour was obtained and it was evenly dispersed. In 30 minutes, bright reddish orange was formed uniformly throughout test tube. In 10% SDS solution sample, in 10 minutes, dark red dye was formed around the beet; slight division of dye observed. In 20 minutes, color was dispersed upwards; dark red colour was formed around the beet and settled at the bottom of the test tube. In 30minutes, solution color was appeared half way up to the test tube; clear division of dark red and clear solution was obtained.

Trial 3:

Figure 3 represents the spectroscopic absorbance of transmission percentage of pigment leakage for given samples such as 10% SDS solution, hot bath, cold bath and distilled water in trial 3.

Figure 3 indicates that spectroscopic absorbance of transmission percentage of pigment leakage for cold bath was higher than other samples. Beet pieces were placed in each sample and the observations were recorded. In cold bath sample, in10 minutes, solution was frozen; dye concentrated at the bottom of the test tube, solution was appeared as dark red in colour and distribution of colour was not uniformly formed. In 20 minutes, solution was appeared slushy; dark red color was remained at the bottom of the test tube; colour of the solution was not dispersed evenly. In 30 minutes, no characteristics change was obtained. In hot bath sample, in10 minutes, solution was appeared like light pinkish red in color; solution was remained uniform in colour. In 20 minutes, solution was appeared brighter in colour than before sample. In 30 minutes, solution was bright reddish orange in colour, and appeared slight darker than previous hot bath solutions. In 10% SDS solution sample, in 10 minutes, dye begins to separate and the solution colour was condensed at the bottom of the test tube. In 20 minutes, solution colour begins to spread upward and the colour was concentrated around the beet piece. In 30 minutes, solution was separated as one third clear solution and two-third dye colour solution.

Discussion:

The purpose of this study was to determine whether environmental factors effects affect the beetroot cell membrane. Based on the obtained result, the effect of the environmental conditions such as temperature and detergents on cell membrane permeability can be explained. Plots of figure 1, figure 2, and figure 3 represent the transmission percentage of pigment leakage of samples in trial 1, trial 2 and trial 3 respectively. Results verified that the factor, temperature affect the beet cell membrane in higher transmission percentage than the detergent. High cell membrane damaged leads to high leakage of pigment from the beetroot cell. In this study, when the beetroot piece was treated with hot bath, 38-47% transmission of pigment was leaked in the solution, in distilled water sample, 96-98% transmission of pigment was leaked in the solution and in cold bath sample, 38-54% transmission of pigment was leaked in the solution. In case of detergent factor (10% SDS solution), 11-15% transmission of pigment was released in the solution. In all three trials, based on the plot drawn (figure 1, figure 2 and figure 3), indicates that distilled water, hot bath and cold bath have the higher transmission percentage of pigment leakage than detergent (10% SDS solution). Therefore, detergent factor causes higher damage on the cell membrane and hence, it result in higher amount of pigment being released from the beetroot cell. The higher the pigment leakage leads to lower the transmission percentage. In the above three plots, detergents have the lower transmission percentage in all three trials. As detergents contain chemicals, it affects the cell membrane. More number of molecules of detergents was absorbed by the cell membrane and pigment (Beta cyanins) in the phospholipids of the cell membrane are repelled and leaked out from the cell. On the other hand, temperature is also one of the major factors affecting the cell membrane. Figure 3 indicates that hot bath sample had 47% transmission pigment leakage, 57% transmission of pigment leakage in cold bath sample and 96% transmission of pigment leakage in distilled water. This result concluded that hot temperature had major effects on the cell membrane and cold temperature causes minor effects on the cell membrane. Proteins of cell membrane are denatured due to the temperature and it result in more leakage of pigment from inside the cell. Hence, as temperature increases, more leakage of pigment may occur and so, hot bath sample had higher membrane damage than cold bath sample. Distilled water had not much effect on the cell membrane as it has higher transmission percentage. Pavel.S et al states in the article that detergents are capable of solubilizing the membrane lipids and proteins. SDS detergent is an anionic denatured detergent and it binds to hydrophobic and hydrophilic sites of the phospholipids membrane. This lead to detergent and phospholipids membrane micelles i.e., interaction of detergent- protein micelles and detergent- lipid micelles (Pavel.S et al, 2005). Due to the detergent-phospholipids micelles, detergent molecules are damaging cell membrane and penetrate into the cell. Therefore, the study concluded that detergent (10% SDS solution) has higher effect on the beet cell membrane than other factor, temperature.

Study of cell membrane permeability using beetroot (Beta vulgaris) is a good demonstration and useful to understand the theories following the cell membrane and how it behaves when affected by the factors such as temperature and chemicals.