Help with Microbiology Science Project Please

[deleted-17599]

Hello! I am currently working on a science project but have seem to hit a bit of a roadblock in creating the experiment. I am trying to biomonitor/bioassay local water systems. I will run tests throughout different sites and compare the microbiological biodiversity to see the health of each system. The problem is, I do not know what equipment exactly I would need. My teacher is not an expert in microbiology and can not offer any help. Does anyone know what technology/tools/equipment I need to be able to identify the different forms of microbiological life? And how exactly I would get the data? Thank you in advance to anyone who may be able to help!

[SciB]

Hi,

I'm confused about what your hypothesis is and what exactly you are doing. What do you mean by 'local water systems'? The water that comes out of the faucet? Are you comparing well water with city water? Please explain a little more about your methods so we can know better how to help you.

Water may contain bacteria such as E coli, protozoans like Cryptosporidium or fungi like Aspergillus. You can see these microorganisms under the microscope but only when there are relatively a lot of them. Your drinking water should contain few or none of these potentially harmful microbes.

The best way to look for microbes in water would be to put a drop on a Petri dish containing nutrient agar, spread the drop over the surface and incubate the plate for a couple of days at 30 C (86 F). Identifying microbial species, however, is challenging even for a microbiologist. You can distinguish bacteria from fungi by their morphology, but identifying the species requires access to a microbiology lab and and a trained person to help you.

Tell us more specifically what your question is and maybe we can help you design experiments to answer it.

Sybee

[deleted-17599]

Hi,
Yeah sorry for the ambiguity. I meant natural water systems. I am running tests on:
-A lake near my school
-A canal in my town that runs down urban sites and farm sites(At different points along it)
-A river near my town(Also along different points)
My aim is to see the health of the ecosystems by seeing the biodiversity among microorganisms. I also was hoping there would be differences depending on where along the stream I grabbed a sample. Since more likely there will be more pollution in urban areas, I hypothesized those areas would have less biodiversity. Essentially my aim for this project is to see the health of these ecosystems through biological means rather than monitoring nutrient levels and such. I hope this clears up the aims of the experiment. I've had trouble designing because I am simply having a hard time finding what exact tests or tools I need to find what I am looking for.
Thank you for your response and I appreciate the help.

[SciB]

You are welcome! Now I understand--great project.

Biodiversity is a hot area of research now partly because of the relative ease of doing DNA sequencing to identify species.
http://www.battelle.org/media/the-batte ... 8part-1%29

While DNA sequencing is the best method for determining biodiversity, it is too expensive for a high school science project. Identifying and counting the critters in water can be done under the microscope--at least for the larger ones like protozoa and multicellular animals like Daphnia and rotifers. In fact, Daphnia (aka 'water fleas') are often used as indicators of water quality: http://www.amnh.org/learn-teach/young-n ... hnia-magna

If you put a drop of water on a Petri dish containing nutrient agar, and incubate it at 30 C (86 F) you will see a number of colonies of various colors and shapes and textures. You can simply count the number of colonies to determine the microbial concentration and you can use the colony characteristics to get a rough idea of the species: https://www.sciencebuddies.org/science- ... ates.shtml

I hope this gives you some ideas about how to design your biodiversity project. Please keep posting with your questions so we can help you make this a really great project.

Sybee

[deleted-17599]

Follow up question, for the nutrient agar is there any specific place you recommend I get it from? Like should I buy and use something like this: https://www.fishersci.com/shop/products ... /p-4523321
or is there a better item you would recommend?
And any other recommendations as to where I should get the items I may need to use?

[deleted-288920]

Hi GioR,

You can purchase agar plates and other items from Carolina Biologics. http://www.carolina.com/. They have very reasonable prices. Good luck with your project, sounds very exciting!

Nikki

[deleted-17599]

Hello again!
Sorry I ask so many questions, trying to compeletely understand the topic and make sure I do everything right.
For the incubation, when you say a couple of days, how many approximately? Is 2 fine or should I do more to make sure the sample is made properly? Also, is there a specific microscope I should use or can most high school microscopes get the job done?
Thank you again for being so helpful!

[deleted-288920]

Good morning!

Ask as many questions as you can! That is what we are here for and its a great way for you to learn.

I would check out the following link from science buddies all about microbiology techniques https://www.sciencebuddies.org/science- ... ques.shtml. This should give you all the answers you are looking for about how to properly grow and look at your bacteria under a microscope.

Nikki

[SciB]

Hi,

I just wanted to add that you should be sure to examine your water samples for the multicellular animals I mentioned before--Daphnia, cyclops rotifers, etc. The Daphnia and cyclops are large enough to see with your unaided eyes once you know what to look for:
https://en.wikipedia.org/wiki/Daphnia
https://en.wikipedia.org/wiki/Cyclops_%28genus%29

Also remember that not all the critters are free-swimming. You will find a lot of protozoans crawling around the mats of algae or water weeds in a pond. Also, there are other species that live in the debris at the bottom of the pond. So, when you take samples for examination, be sure to check all areas of the pond to get a representative population.

To see and photograph protozoa you need a microscope with a magnification of at least 100X (10X eyepiece and 10X objective lens). To see bacteria and single-celled algae, you need at least 400X (10X eyepiece and 40X objective). Most school microscopes have these lenses. Watch this video on Life in a Drop of Water--it shows all the little critters you are likely to see and more: https://www.youtube.com/watch?v=_cpBK2t0Yeo

Taking pictures is very important for your project but you don't need a fancy camera and attachments to get decent photos through the microscope. If you have a digital camera you can use that. I have used both a camera and a smart phone and got some good photos of Daphnia, protozoa and algae. If you do a google search you can find lots more information:

http://howto.wired.com/wiki/Take_Microphotographs
http://smartphones.wonderhowto.com/how- ... pe-350098/
https://www.youtube.com/watch?v=cfd9ViHBlR4

I'm sure you will have lots more questions--and as Nikki said, ask as many as you want!

Good luck,

Sybee