Basella Rubra Fruit Extract

4. It would be difficult to measure the concentration of acid in red wine or coca-cola because the colour of the drink is too dark for us to see when the phenolphthalein indicator changes colour. You could overcome this difficulty by using a pH meter.

1. Benedict’s solution is added to white grape juice and heated. The color changes from blue to orange. Based on this result, what biological molecules are

If the broth turns yellow, it means that acid was produced and reported as A. If the organism can break down the amino acids be de-amination and ammonia is produced, this will raise the pH level turning it pink. This alkaline result was reported as K.

Boynton, R.M. 1987. Color. In McGraw-Hill Encyclopedia of Science & Technology (Vol. 4, 165-166) McGraw-Hill, Inc.

Vinegar is a common household product, when mixed with the indicator, phenolphthalein, it turns pink. This indicates that Vinegar is acidic.

Most enzymes have an optimum pH of around 7, which is fairly neutral. To ensure the experiment is a fair test, I will use the same pH of hydrogen peroxide in every test.

Betalaines are the red pigments of beetroot. They are water-soluble and exist as internal salts in the sap vacuoles of plant cells. Betalaines are made up of red betacyanins and yellow betaxanthins. Betacyanines include about 90% of beetroot betalaines. The most important betacyanin is betain. This makes up 75-95% of the total colouring found in the beetroot. Jm

The cell membrane (Plasma membrane) functions to provide cell support, cell stability and control entry and exit of materials from the cell. This study was conducted to test the effects of environmental conditions such as the on beet root cell membrane (Beta vulgaris). Five trials using varied pH concentrations were tested and absorbance rates were monitored. The experimental results showed that the protein function decreased sequentially when the pH decreased. This allowed the betacyanin dye to leak out which created the color that was needed to determine the intensity and therefore the effect of the circumstances. This supported the hypothesis that the more acidic or basic the environmental condition around the beet cell, the more permeable the, membrane indicated by color intensity. Pigment leakage in the solution was analyzed by using a spectrophotometer.

Beets also known as Beta Vulgaris, contain a pigment known as betacyanin that gives the beets its deep rich red color, it is water soluble and is stored in the vacuoles of the beet roots and stems. Because the betacyanin is a water soluble pigment is can not easily cross the cell membranes.

Table 2: Consists of color extract taken from a red cabbage for a natural indicator. The pH reading that was measured by using the pH meter and the result of the pH reading to determine whether the solution was acidic or basic.

The medium contains sodium citrate that serves as sole carbon source and ammonium phosphate as the sole nitrogen source. These organisms produce the enzyme citrate-permease that can transport the citrate into the cell and produce pyruvate from it. Bromthymol blue dye is used as an indicator that is green at pH 6.9 and blue at pH 7.6 and above (Leboffe and Pierce). A positive result is obtained if the color is blue meaning that bacteria utilize the citrate and convert the ammonium phosphate into ammonia and ammonium hydroxide.

Mannitol Salt Agar contains the carbohydrate mannitol, 7.5% sodium chloride (NaCl), and a pH indicator called phenol red. At pH levels below 6.9, the medium is a yellow color. In the neutral pH ranges (6.9 to 8.4) the color is red; while above pH 8.4, the color of phenol red is pink (Gerhardt P., 2011). Acid is produced when mannitol is fermented by bacteria, which lowers the pH and results in the formation of a yellow halo surrounding the isolated colony on MSA. Non-fermenting bacteria that withstand high salt concentrations will display a red to pink area due to peptone breakdown (Mahon C.R. et al.

Catechol, in the presence of oxygen is oxidized by catechol oxidase to form benzoquinone (Harel et al., 1964). Bananas and potatoes contain catechol oxidase that acts on catechol which is initially colorless and converts it to brown (Harel et al., 1964). In this experiment, the effect of pH on the activity of catechol oxidase was conducted using buffers ranging from pH2 to pH10. Two trials were conducted due to the first trial results being altered by an external factor. The results were acquired by taking readings every 2 minutes for 20 minutes from a spectrophotometer and then recorded on to the table. The data collected in the table were then made into graphs to illustrate the influence of pH on the catechol oxidase catalyzed reaction. After analysis, the data revealed that pH did have a significant influence on the enzyme as recorded by absorbance per minute. However, the data was collected was not accurate due to external factors, thus the results are debatable and should be experimented again for validation.

By using acid-base titration, we determined the suitability of phenolphthalein and methyl red as acid base indicators. We found that the equivalence point of the titration of hydrochloric acid with sodium hydroxide was not within the ph range of phenolphthalein's color range. The titration of acetic acid with sodium hydroxide resulted in an equivalence point out of the range of methyl red. And the titration of ammonia with hydrochloric acid had an equivalence point that was also out of the range of phenolphthalein.. The methyl red indicator and the phenolphthalein indicator were unsuitable because their pH ranges for their color changes did not cover the equivalence points of the trials in which they were used. However, the

For lab 12, it is hypothesized that chlorophylls a and b are present in a plant leaf and contribute to the starch production in photosynthesis. Also, products of photosynthesis will be present in leaf tissue exposed to red and blue light wavelengths for several days, but a decreased presence in leaf tissue exposed to green and black light wavelengths. In lab 13, it is expected that since chlorophylls a and b are more polar and smaller molecules than the anthyocyanins and carotenoids, they will travel higher up the chromatography paper than the other pigments.