Effects Of Acetaminophen on
Microbial Flora
Renne Cabacungan
Grade 9
Central Catholic High School
Microbial Flora
• Little is known about the association between humans and their
flora
• Effects are mutualistic, parasitic, pathogenic and commensal
• Provide nutritional and digestive benefits, secrete vitamins,
stimulate antibody production, and protect against pathogenic
microbes
• Can drugs effect the behavior of microbial flora?
Escherichia coli
• Gram-Negative, rod-shaped bacterium found in the intestines and
stomach
• Commonly studied because it is easily manipulated
• Major role in digestion and the GI tract.
• E.coli can be harmful or beneficial
Acetaminophen
• Commonly used over-the-counter medication used to treat
headaches, backaches, toothaches, cold, and flu aches
• Acetaminophen is still being studied, as scientists are still not certain
how exactly it works.
• Although the drug itself is normally non-toxic, overdose can cause
liver failure
Infant’s Tylenol
• In infant’s Tylenol, acetaminophen is in the liquid form.
• It contains: cellulose, citric acid, corn syrup, FD&C Red #40, flavors,
glycerin, purified water, sodium benzoate, sorbitol, xanthan gum.
• The therapeutic dose of Tylenol is 160 micrograms per 5 ml.
• The therapeutic blood level of acetaminophen is 10-20 micrograms
per ml.
Potential Interactions
• Exposure to acetaminophen can kill off certain types
of bacteria, while others developed increasing
resistance.
• A past study showed that acetaminophen had an
effect on the survivorship of E.coli.
Purpose/Problem
• The purpose of this experiment is to determine the
effects of various concentrations of acetaminophen
on E.coli survivorship.
Hypotheses
• Null Hypothesis: Tylenol in various concentrations will
have no effect on the survivorship of E.coli.
• Alternative hypothesis: Tylenol in various
concentrations will have a significant effect on the
survivorship of E.coli.
Materials
• Luria Broth Agar plates (0.5%
yeast extract, 1% tryptone, 1%
sodium chloride)
• Infant’s Tylenol (Grape flavored)
• Micropipette and tips
• Vortexer
• Incubator (37 degrees Celcius)
• 4 sterile, capped test tubes
• Sterile Spreader bars
• Ethanol
• Bunsen Burner
• Sterile Dilution Fluid (10mm
KH2PO4, 1 mm MgSO4, .1mm
CaCl2, 100 mm NaCl)
• Test Tube racks
• Escherichia coli
Procedure (Liquid Exposure)
1. Concentrations of Tylenol solutions were made in sterile
tubes.
2. E.coli was grown in sterile, sidearm flask until a density of
10^8 cells/ml in a 50 klett spectrophotometer.
3. Culture was diluted in sterile dilution fluid to a
concentration of approximately 10^5 cells/ml
4. The solutions were vortexed and were allowed to sit in
room temperature for 15 minutes.
Concentrations
Total Volume
Sterile
Dilution Fluid
Tylenol
E.coli
Concentration
10 ml
9.9 ml
0 ml
0.1 ml
0%
10 ml
9.89 ml
0.01 ml
0.1 ml
0.1%
10 ml
9.8 ml
0.1 ml
0.1 ml
1%
10 ml
8.9 ml
1 ml
0.1 ml
10%
Procedure (cont.)
5. Spreader Bars were sterilized with ethanol and a Bunsen
burner.
6. 100 ul of E.coli was removed from the tubes and spread
onto LB plates.
7. Plates were incubated for 24 hours.
8. The resulting colonies were counted visually.
Procedure (Infusions)
1. Pipetted 200 uL of pure Tylenol onto four plates.
2. Pipetted 180 uL Sterile dilution fluid and 20 uL Tylenol onto four
plates.
3. Pipetted 0.1 ml of the control tube onto each plate.
4. Incubated for one day at 37 degrees Celsius.
5. Recorded number of colonies.
Results (Liquid Exposure)
Number of Colonies
250
200
P Value:
2.4E^-10
200
150
100
50
10
3
4
0
0%
0.10%
1%
Concentration of Tylenol
10%
Dunnett’s Test (Liquid)
Concentration
T value
T crit. value
Conclusion
0.1%
18.68
3.29
Significant
1%
19.34
3.29
Significant
10%
19.24
3.29
Significant
Results (Infusion)
250
Number of Colonies
200
P Value:
3.3E^-8
200
150
100
50
2
0
Control Group
0
0.10%
1%
Concentration of infusion
Dunnett’s Test (Infusion)
Infusion
Concentration
T Value
T Critical Value
Conclusion
Low
9.51
2.57
Significant
High
17.51
2.57
Significant
Conclusions
• The data for both infusions and concentrations
suggest to reject the null hypothesis.
• Tylenol in various concentrations (0.1%, 1%, and
10%) does have a significant, negative effect on
the survivorship of E.coli.
Limitations
• Potential spreading errors could have occurred.
• E.coli population could have aged.
• Only E.coli was tested.
• Only one liquid pulse exposure time
• Narrow range of concentrations
Extensions
• Wider range of concentrations
• Test different over-the-counter drugs such as Ibruprofen,
Advil, etc. (synergistic effects)
• Test different forms of Tylenol or acetaminophen
• Test Staph or other microbial models
Sources
•
http://www.webmd.com/drugs/2/drug-7076/tylenol-oral/details
•
http://www.cdc.gov/ecoli/general/
•
http://www.healthline.com/health/e-coli-infection#Symptoms2
•
http://tuftsjournal.tufts.edu/2008/04/professor/01/
•
http://www.chemistryexplained.com/A-Ar/Acetaminophen.html
•
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2889646/
•
http://www.eurekalert.org/pub_releases/2007-09/acs-mld092407.php
•
http://www.ehealthme.com/ds/tylenol/e.+coli+diarrhea
•
http://www.labtests online.org
•
http://www.cdc.gov/ecoli/2015/o26-11-15/
•
http://pelagiaresearchlibrary.com/european-journal-of-experimental-biology/vol4-iss2/EJEB-2014-4-2-351-356.pdf
•
http://www.ncbi.nlm.nih.gov/pubmed/21558695
•
http://www.the-scientist.com/?articles.view/articleNo/38325/title/Ever-Evolving-E--coli/
•
http://www.acs.org/content/acs/en/pressroom/presspacs/2013/acs-presspac-october-2-2013/recruiting-e-coli-to-combat-hard-to-treat-bacterialinfections.html
•
http://www.health.state.mn.us/divs/eh/risk/guidance/dwec/acetamininfo.pdf
ANOVA (Liquid Exposure)
Anova: Single Factor
SUMMARY
Groups
Count
0
4
0.0001
4
0.01
4
0.1
4
ANOVA
Source of VariationSS
Between Groups
113208.3
Within Groups2483.5
Total
115691.8
Sum
Average
798
199.5
38
9.5
11
2.75
15
3.75
df
Variance
774.3333
39
1.583333
12.91667
MS
F
P-value
F crit
3 37736.08 182.3366 2.84E-10 3.490295
12 206.9583
15
ANOVA (Infusion)
Anova: Single Factor
SUMMARY
Groups
Count
Control
4
Low
4
High
4
ANOVA
Source of VariationSS
Between Groups
105080.7
Within Groups 2337
Total
107417.7
Sum
Average Variance
798
199.5 774.3333
8
2 4.666667
0
0
0
df
MS
F
P-value
F crit
2 52540.33 202.3376 3.3E-08 4.256495
9 259.6667
11