1. Can Aspargaus
inhibit population
growth of yeast
cells?
Tiffany Sato
Experium Science Academy
Marlborough School, Ninth Grade

2. Hypothesis and Goals
 During digestion, asparagus produces sulfur
compounds, which is beneficial in the reduction of
the growth of cancer cells (Mitchell, 2001).
Therefore, I decided to investigate this further which
led me to the information that asparagus produced
high levels of sulfur. From this, I decided to start
studying the effect of asparagus on yeast activity.
 I wanted to see a decrease in yeast activity
compared to a negative and positive control. A
decrease in growth meant that the asparagus, the
high amounts of sulfur, was inhibiting the growth of
the yeast cells.

3. Why I used Yeast Cells
and the Similarities
 Yeast Cells  Cancer Cells
(Saccharomyces  Typical eukaryotic
cerevisiae) structure
 Typical eukaryotic  Fast and
structure incontrollable cell
 Fast and division
incontrollable cell
division
 Economically
accessible
 Genetic material is
known

4. Yeast Cells as a Model
Organism
 I realized that scientific studies have shown
thatSaccharomyces cerevisiae could be used as an
alternative to cancer cells when doing research.
(Hartwell, 2001) (Mortimer, 1973)

5. Research Methods

6. Can Asparagus
inhibit population
growth in yeast cells?
Yeast Activity Viable Colony
Growth with Counts with Agar
Spectrophotometer Plates

7. Recipes
Positive (YPD+)
• 1% Yeast Extract
• 2% Peptone
• 1% Dextrose
Negative (YPD-)
• Water
Experimental (YPDAsp)
• 1% Yeast Extract
• 2% Peptone
• 1% Dextrose
• 50mL of Filtered Asparagus

8. Yeast Activity Growth
with Spectrophotometer
Grow S. cerevisiae Centrifuge all
Incubated all
in YPD+, YPD- the different
cultures for 24 hours
, YPDAsp Broths mediums
Measured the
absorbance of each
using a Compared the Yeast
spectrophotometer at Activity Growth Results
600nm

9. Viable Colony Counts
using Agar Plates
For my agar
plates, I Streak onto my
inoculated a three different
Incubate for 48
plates:
colony from a hours at 30oC
positive, negative
colony off a and experimental
positive plate.
Incubate for 24 hours Record Viable Colony
at 30o C Count Results

10. Results for Yeast Growth
Activity

11. Absorbance of Yeast
Activity Sample
1
0.9
0.8
Absorbance (600nm)
0.7
0.6
0.5 POSITIVE
0.4 NEGATIVE
0.3 EXPL
0.2
0.1
0
0 5 10 15
Sample Numbers

12. Data Table

13. Data
 Average for Negative (without any nutrients) :
0.189 abs
 Average for Experimental (with asparagus):
0.488 abs
 Average for Positive (with nutrients, without
asparagus):0.633 abs

14. Conclusions for Yeast
Growth Activity
 My results from my experiment with the liquid
medium with asparagus had the lowest absorbance
(0.488 abs) compared to my positive control
(0.633 abs ) and higher absorbance compared to
my negative control (0.189 abs). This indicates a
decrease in yeast activity upon addition of
asparagus indicating minimal cell growth.

15. Results for Viable
Colonies

16. Experimental
Results

17. Comparison of the
Controls
Negative Experiment Positive Experiment

18. Conclusions from Viable
Colonies
 Although viable colonies have limited
quantification, the pictures show the apparent
difference of structural colonies between the
Positive, Experimental, and Negative.
Positive Experimental Negative
• Raised, Corvex • Flat Surface • Produced no
Surface colonies

19. Acknowledgements
Thank you to Sigma Xi for this opportunity.
Thank you to RaudhahRahman, Experium
Science Academy, my parents, and those who
have supported me throughout.