Transcript E.coli, S. aureus, and B. Cereus.

Effect of Penny Composition on Escherichia coli, Bacillus
cereus, and Staphylococcus aureus Bacteria
Tim O’Hanlon Department of Biology , York College
Methods
Introduction
•Pennies can be fomites for passing
Spread plate 3 groups of bacteria E.coli,
bacteria.
S. aureus, and B. Cereus.
•Pennies are made from
N=30
for
each
group
combinations of zinc, tin, and
copper.
•The government has changed
penny composition over the years
30
Pennies
30
pennies
30
pennies
changing the copper content.
Prior
to
1962
1962-1982
after
1982
•Copper has lethal effects on
bacteria.
•Different bacteria have different
tolerances to antibacterial
substances.
Incubate 37° for 24 hours
•Larger copper contents may give
the pennies a greater antibacterial
effect.
Hypothesis
H0: There will be no difference
between the pennies antibacterial
effects.
Ha: Pennies with the highest copper
concentrations will have the greatest
antibacterial effect.
Results
Table 1.
Zone Of Inhibition (mm)
Escherichia Coli
Bacillus Cereus
Prior to
1962
19621982
After
1982
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Staphylococcus Aureus
Prior to 1962- After
1962
1982 1982
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Prior to
1962
19621982
After
1982
3.6
4.8
3.4
4.9
4.8
4.2
4.1
2.6
3
2.3
3.8
3.4
2.7
3.7
0
1.1
2.3
4.8
4.6
2.1
3.3
3.8
Figure 1.
Measure Zone of
Inhibition
Fig. 1. Zone of inhibition for E. coli with standard error bars. No
signifigance was found.
Statistical analysis of
results
Conclusion
•There was no Inhibitory effect on B.
cereus or E. coli for any of the groups.
•All groups had a fairly high lethal
effect on S. aureus.
•There was no significance between
the two statistical groups for S. aureus
Acknowledgements
A special thanks to Dr. Mathur for all her help and her patience on this project and thanks
to the entire biology department for motivating me and supporting me during my time
here.