The Effects of Olive Oil on E. coli Survivorship Galen Lovejoy 9th Grade Central Catholic High School 1st Year participating in PJAS

Problem How does Olive Oil effect the survivorship of the bacteria Escherichia coli?

Olive Oil Scientific Name: Olea europaea Regarded as one of the world’s healthiest fats Used for cooking One of the world’s oldest cooking ingredients

Chemical Makeup of Olive Oil Olive Oil fat is a triacylglycerol. Triacylglycerols are formed by three fatty acids joining to a glycerol molecule. Olive Oil also has free fatty acids that are mostly monounsaturated.

Microbial Flora Refers to microorganisms living in the human body, including the gastrointestinal tract.  Little is known about the association between humans and their microbial flora. The four effects are mutualistic, parasitic, pathogenic, and commensal. Perform functions beneficial to the host, including the manufacturing of essential vitamins, and the prevention of colonization by undesirable microbes.

Previous Studies Previous studies show that olive oil has negative effects on bacteria. Though studies also show that gram (-) bacteria are more resistant to it.

Escherichia coli Largest group of known bacteria Resides in the lower human tract system Gram (-) Bacteria Common prokaryotic cell model used in scientific studies

Purpose To determine if olive oil has a significant effect on on E. coli survivorship.

Hypotheses Null Hypothesis (only used for statistical analysis)- The Olive Oil will not have a significant effect on E. coli survivorship. Alternate Hypothesis (formal hypothesis)- The Olive Oil will significantly alter survivorship of E. coli.

Materials E. coli C600 100% Virgin Olive Oil YEPD agar plates (1% yeast extract, 2% peptone, 2% glucose) E. coli C600 Sterile dilution fluid (100mM KH2PO4, 100mM K2HPO4, 10mM MgSO4, 1mM NaCl) Sterile Test Tubes Sterile Spreader bars Sterile Micropipets Sterile Macropipets Incubator 100% Virgin Olive Oil Ethanol

Procedure 1. A culture of E. coli C600 was grown overnight. 2.The culture of cells was diluted to a concentration of 10^8 cells/ml. 3. The following ingredients were used to create the desired exposures.

Concentration Table 0% (Control) 0.1% Olive Oil 1% Olive Oil Microbe 0.1 ml SDF 9.9 ml 9.89 ml 9.8 ml 8.9 ml Olive Oil 0 ml 0.01ml 1 ml Total Volume (ml) 10 ml

Procedure 4. The test tubes were then mixed through inversion for 10mins to emulsify the solution. 5. Samples of 0.1ml were taken from each tube and plated onto YEPD agar plates. 6. 8 replicates were plated for each tube. 7. The plates were incubated at 37˚C for approximately 18 hours. 8. The resulting colonies were counted visually. Each colony was assumed to have arisen from one cell.

Effects of Olive Oil on E. coli Survivorship P-Value 3.309E-08

Dunnett’s Test Results Concentration Groups T-Value T-Crit Value Results 0.1% 3.11 2.95 Significant 1% 4.8 10% 8.62

Conclusion The null hypothesis was rejected for all concentrations of olive oil. The alternative hypothesis was accepted for all concentrations of olive oil. The results of the statistical analysis indicates that all concentrations of olive oil significantly increased E. coli survivorship. (Growth stimulant?)

Only one type of olive oil was tested. Limitations Extensions Only one type of olive oil was tested. The cells could have had longer or shorter exposure times. The plating was not perfectly synchronized. Only one type of cell was tested. Other types of olive oil could be use as a variable. Prolong the amount of time the cells were exposed to the olive oil. Increase effort to plate all concentrations as close as possible. Use another cell model, such as yeast.

Works Cited http://www.medicinenet.com/script/main/art.asp?articlekey=5549 http://web.uconn.edu/mcbstaff/graf/Student%20presentations/S% 20epidermidis/sepidermidis.html http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2807625/ http://www.mayoclinic.org/diseases-conditions/e- coli/basics/definition/con-20032105 http://www.cdc.gov/ecoli/ http://www.mayoclinic.org/healthy-living/nutrition-and-healthy- eating/expert-answers/food-and-nutrition/faq-20058439 http://www.oliveoiltimes.com/olive-oil-health-benefits http://www.cnn.com/2013/02/26/health/five-things-olive-oil/ https://www.pritikin.com/your-health/healthy-living/eating- right/1103-whats-wrong-with-olive-oil.html#.VKiIqUc8KrU http://www.oliveoilsource.com/page/chemical-characteristics

ANOVA Anova: Single Factor SUMMARY Groups Count Sum Average Variance Row 1 8 573 71.625 168.83929 Row 2 705 88.125 126.41071 Row 3 776 97 88.857143 Row 4 939 117.375 66.839286 ANOVA Source of Variation SS df MS F P-value F crit Between Groups 8717.3438 3 2905.7813 25.774957 3.309E-08 2.9466853 Within Groups 3156.625 28 112.73661 Total 11873.969 31