The document summarizes an experiment that tested the effect of varying pH levels on the release of betacyanin pigment from Beta vulgaris (beet) root cells. Beet root disc samples were placed in solutions with pH levels of 2.0, 7.7, and 12.0, then their absorbance was measured to determine betacyanin release. Absorbance was highest at pH 2.0 and lowest at pH 7.7, supporting the hypothesis that lower pH causes more cell damage and betacyanin release. Experimental errors and modifications are discussed.

1. Effect of Varying pH on the
release of Betacyanin from
Beta vulgaris root cells
Brittney Fiselier and Kierra Walker
Red Deer College - Red Deer

2. Introduction
• If the pH of the surrounding environment of a Beta vulgaris beet root is
lowered, then more red pigment, betacyanin, will be released because more
cell damage will be done.
• The variation that was presented to the Beta vulgaris root cells was varying
pH levels of 2.0, 7.7 and 12.0.
• According to Reid et al, who studied the effects of pH on betacyanin leakage
from beet root discs, the lower the pH, the more pigment is released.
• According to Jacobsohn et al, who studied cell membranes and the influence
of pH on solvent induced damage, betacyanin is released at its maximum at
a pH of 2.0 and little leakage at pH of 6.6 and 10.0.
• According to Thimmaraju et al, who studied the kinetics of pigment release
from hairy root cultures of Beta vulgaris under the influence of pH,
sonication, temperature and oxygen stress, about 70% of the betacyanin was
obtained within 30 mins when the beet root was placed in an acidic medium
of pH 2.0.

3. Methods
Ten 5 mm discs of a sample of a Beta vulgaris beet root was obtained and rinsed for 10 mins.
Nine test tubes were labelled three of HCl, three of NaOH, and the remaining three of H20. A
sample size of 3 was used and three discs were placed in each solution for exactly 2 mins. Each
disc sample was placed in the appropriate test tube containing distilled water for 30 mins,
being vortexed every 10 mins. Using a pipette, 10 mL of each sample was obtained and placed
in a cuvette which was used in the Spectrophotometer 20 to measure the absorbency at a
wavelength of 525 nm.
Our control was the sample of pH of 7.7 (distilled water). This mimics the natural pH range of
a Beta vulgaris beet root.

4. Results
0.08
0.06
Absorbance
@ (525 nm)
0.04
0.02
0
2.00 HCl 7.70 H2O 12.00 NaOH
pH of solution

5. Discussion
• Our hypothesis was supported by our results; Beta vulgaris membrane
cells are damaged when the pH of its environment decreases.
• It can be concluded that Beta vulgaris beet roots would not grow as
healthy in low pH soil because their membrane cells would not be
able to withstand the acidity, causing damage to the central vacuole
which contains the red pigment, betacyanin.
• Experimental errors include the precision of the disc samples of the
beet root because a non-scientific ruler was used to measure 5 mm,
misreadings of the Spectrophotometer 20 could have been incorrect if
careful measures were not taken by using the mirror behind the
needle and the blank sample used to calibrate the Spectrophotometer
may have contained some betacyanin on the outside of the cuvette.
• Modifications to incorporate could be to take care in more precision
when taking any measurements and to test more variations of pH
ranges to get more exact results.