Water Source Influence of Microbial Survivorship

By Zachary PoppishGrade 9Central Catholic High School Pittsburgh

Rationale:

● Water sources can vary greatly in their quality and properties.

● Various types of microbes exist in natural water sources.

● Do river water and creek water vary significantly in their ability to support prokaryotic and eukaryotic microbial life?

Common Creek and River Pollutants

Detergents

Fertilizers

Animal waste

Automotive products

Pesticides

Can runoff products aid or hinder microbial growth?

Allegheny River

The sample of the River was taken along the side of a railroad track.

Many pollutants in the Allegheny River from:

Tires, garbage, styrofoam, plastic, lumber and many other pollutants

Deer Creek

The area of Deer Creek where my sample was taken is near a small industrial park

This includes:

● A metal shop that carries petroleum● A trucking distribution center.● A PennDot station with road salt● A Brick yard and Lumber Mill

Microbes Tested

Escherichia coli (E.coli)

Saccharomyces cerevisiae (Yeast)

Escherichia coli (E.Coli)

● Gram-negative microflora● Found in the intestines of

warm-blooded animals as well as excrement

● Most varieties are harmless, though some can cause illnesses.

Saccharomyces cerevisiae (Yeast)

● Single celled fungi● Most commonly studied

organism- similar biochemistry and genes as other Eukaryotes

● Gram-Positive microflora● Most commonly called yeast

or baker's yeast

Materials used1. 72 YEPD agar plates(1% yeast extract, 2%

peptide, and 2% glucose)2. Sterile pipette tips3. Micropipettes4. Vortex5. Incubator 6. Spreading turntable7. Spreader bar8. Escherichia coli (e.coli)9. Saccharomyces cerevisiae (yeast)

10. Sample water from Deer Creek11. Sample water from the Allegheny

River12. Sample of SDF (100mM KH2PO4,

100mM K2HPO4, 10mM MgSO4, and 1mM NaCl)

Procedure

1. Collected samples from local creek and river in a sterile container2. Sterilized the 2 water samples using 0.2 micron syringe filter3. The waters were transferred to sterile 15 mL conical tubes4. The yeast and E. coli were diluted from their stocks to a tube with

a concentration of 10^5 cells per mL5. 100 microliter samples of the microbes were transferred into the

water samples6. The tubes were incubated at room temperature for 5 min and 1 hr7. After 5 and 60 minutes 100 microliters of the mixtures were

transferred to YEPD agar plates.8. Plates were incubated (yeast= 37C for 48hr and E. coli 37C for

24hr)9. The resulting colonies were counted

Variables

Independent: Exposure Time/Water sample/Microbe used

Dependent: Amount of colonies

Control: Sterilized water

Hypothesis

Alternative: The natural water bodies will reduce the microbial survivorship.

Null: The waters samples will not significantly hinder the microbes survivorship.

E. coli average colonies

P-value:5 min: 0.74706160 min: 0.002009

Dunnett’s Test-E. coli

F-Crit:3.885 Creek River

5 min Unable to dunnett’s test because data was not significant

Unable to dunnett’s test because data was not significant

1 hr -8.026-Significant -1.538-insignificant

Yeast Average Colonies

P-value:5 min: .0.00123360 min: .0.587849

P-value:5 min: 0.00011660 min: 0.829171

Dunnett’s Test-Yeast

F-crit:3.885 Creek River

5 min 9.937-significant .177-insignificant

1 hr Unable to dunnett’s test because data was not significant

Unable to dunnett’s test because data was not significant

Percent Survivorship

Conclusion

The alternative Hypothesis was supported for 2 of the cases. The E. Coli survivorship was reduced after 1 hour in the creek. The creek appeared to enhance yeast growth after 5 minutes.

The null was accepted for all other waters/times.

Reason

● Different pH values?● Different minerals and other ions?● Different types of pollutants?

Limitations

1. Tested only one river and one creek

2. Only 2 time periods tested3. Only survivorship and no other health parameters4. Unknown composition of waters

5. Water was taken from river and creek during winter months

Improvements

1. Test multiple creeks and rivers to test for pollutants/different areas (RESIDENTIAL, AGRICULTURAL AND URBAN)

2. Do a chemical analysis of the waters

3. Test during different times of the year/temperatures

4. Test lakes and ponds for pollutants

Works cited

https://about-ecoli.com/http://www.waterencyclopedia.com/La-Mi/Microbes-in-Lakes-and-Streams.html https://www.lenntech.com/rivers-pollution-qualityhttps://people.uwec.edu/piercech/hml/Common%20sources%20of%20water%20pollution.htmhttps://redstaryeast.com/science-yeast/what-is-yeast/ https://wiki.yeastgenome.org/index.php/What_are_yeast%3F

Overall Results:I 5 MINUTES 1 HOUR

E-coli

Sterilized Water 435 421

Creek Water 326 239

River Water 414 391

Yeast

Sterilized Water 62 42

Creek Water 216 38

River Water 64 45

● E-coli higher survivorship in 5 min versus 1 hour

● Reason: Less exposure to chemicals in water

E-Coli: SDF

Time Test #1 Test #2 Test #3 Test #4 Test #5 Test #6 Average

5 Min 460 452 440 404 432 424 435

1 HR 408 420 400 451 384 464 421

P-Value: 0.367479668

Highest Survivorship:

5 minutes : Test #1 with 460 colonies

1 HR: Test #6 with 464 colonies

On Average: E-coli survivorship is higher after 5 minutes

E. COLI SDF (Sterilized Water)

Yeast: SDF

Time Test #1 Test #2 Test #3 Test #4 Test #5 Test #6 Average

5 Min 87 35 70 55 54 69 62

1 HR 39 46 34 44 34 52 42

P-Value: 0.027479

Highest Survivorship:

5 minutes : Test #1 with 87 colonies

1 HR: Test #6 with 52 colonies

On Average: E-coli survivorship is higher after 5 minutes

YEAST SDF (Sterilized Water)

E-Coli: Creek Water

Time Test #1 Test #2 Test #3 Test #4 Test #5 Test #6 Average

5 Min 240 101 540 344 410 320 326

1 HR 400 296 248 136 288 67 239

P-Value: 0.293216

Highest Survivorship:

5 minutes : Test #3 with 540 colonies

1 HR: Test #1 with 400 colonies

On Average: E-coli survivorship is higher after 5 minutes

E. COLI CREEK WATER

Yeast: Creek Water

Time Test #1 Test #2 Test #3 Test #4 Test #5 Test #6 Average

5 Min 208 216 424 176 104 168 216

1 HR 28 60 38 43 47 9 38

P-Value: 0.002736

Highest Survivorship:

5 minutes : Test #3 with 424 colonies

1 HR: Test #2 with 60 colonies

On Average: E-coli survivorship is higher after 5 minutes

YEAST CREEK WATER

E-Coli: River Water

Time Test #1 Test #2 Test #3 Test #4 Test #5 Test #6 Average

5 Min 308 526 368 524 364 392 414

1 HR 408 400 432 320 360 424 391

P-Value: 0.586029

Highest Survivorship:

5 minutes : Test #2 with 526 colonies

1 HR: Test #6 with 424 colonies

On Average: E-coli survivorship is higher after 5 minutes

E. COLI RIVER WATER

Yeast River Water

Time Test #1 Test #2 Test #3 Test #4 Test #5 Test #6 Average

5 Min 33 51 84 92 38 88 64

1 HR 55 32 50 48 35 49 45

P-Value: 0.121499

Highest Survivorship:

5 minutes : Test #4 at 92 colonies

1 HR: Test #1 at 55 colonies

On Average: Yeast survivorship is higher after 5 minutes

YEAST RIVER