Can Aspargaus inhibit

population growth of

yeast cells?

Tiffany Sato

Experium Science Academy

Marlborough School, Ninth Grade

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.

Yeast Cells

(Saccharomyces

cerevisiae)

Typical eukaryotic

structure

Fast and

incontrollable cell

division

Economically

accessible

Genetic material is

known

Cancer Cells

Typical eukaryotic

structure

Fast and

incontrollable cell

division

Why I used Yeast Cells

and the Similarities

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)

Research Methods

Can Asparagus inhibit population

growth in yeast cells?

Yeast Activity Growth with

Spectrophotometer

Viable Colony Counts with Agar

Plates

Recipes

• 1% Yeast Extract

• 2% Peptone

• 1% Dextrose

Positive (YPD+)

• Water

Negative (YPD-)

• 1% Yeast Extract

• 2% Peptone

• 1% Dextrose

• 50mL of Filtered Asparagus

Experimental (YPDAsp)

Yeast Activity Growth

with Spectrophotometer

Grow S. cerevisiae in YPD+, YPD-

, YPDAsp Broths

Incubated all cultures for 24 hours

Centrifuge all the different

mediums

Measured the absorbance of each

using a spectrophotometer at

600nm

Compared the Yeast Activity Growth Results

Viable Colony Counts

using Agar PlatesFor my agar

plates, I inoculated a

colony from a colony off a

positive plate.

Incubate for 48 hours at 30oC

Streak onto my three different

plates: positive, negative and experimental

Incubate for 24 hours at 30o C

Record Viable Colony Count Results

Results for Yeast Growth

Activity

Absorbance of Yeast

Activity Sample

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

0 5 10 15

Ab

so

rba

nc

e (

600n

m)

Sample Numbers

POSITIVE

NEGATIVE

EXPL

Data Table

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

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.

Results for Viable

Colonies

Experimental

Results

Comparison of the

ControlsNegative Experiment Positive Experiment

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

• Raised, Corvex Surface

Experimental

• Flat Surface

Negative

• Produced no colonies

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.