With all of the publicity about how plastics are piling up in landfills and the ocean there has been an assumption that the plastics are incapable of breaking down. During my undergrad as a Microbiology major at Cal Poly SLO I was interested in environmental microbiology. During this time I was given a link to an article about a Canadian teenager, Daniel Burd, who found an aerobic (grows in presence of oxygen) bacteria that can degrade plastic. Well this got me thinking, maybe the whole idea that plastics could be degraded actually made sense, I mean there are some really complex molecules in nature that can be broken down, why not the simple design of plastics. So I started planning an experiment, looking for anaerobic (grows without oxygen) bacteria that degrade plastic using a Winogradsky Column which consists of soil at the bottom of the column and liquid at the surface of the column, limiting the amount of air that can diffuse into the soil. I did this with the hope that if I could find plastic degrading bacteria I could make a microbial fuel cell which would essentially breakdown plastic and produce electricity at the same time. Yes, a little ambitious but worth a try. If you are interested in how I went through developing the procedure and results please feel free to read the following paragraphs. If you just want to get straight to business skip to the the next page! 

With a vague idea of what Daniel Burd had done with his aerobic experiment I decided to design a similar experiment. In just a small sample of soil there are literally millions of bacteria, most are unable to be cultured in a lab. These bacteria and their relationships are so complicated that we may never be capable of understanding the exact ecology of a population of microbes in a spoonful of soil. With this general idea in mind it made sense to me that if put into an extreme environment, the microbes would adapt in order to survive. The nice thing with microbes is their ability to adapt quickly, turning on and off a variety of metabolic pathways to best utilize the resources available to them. That is exactly why microbes can be found almost everywhere on the planet. So my idea was to put soil microbes in an environment full of all the tasty elements they use to grow. I used Bushnell Hass Broth which is composed of Magnesium Sulfate, Calcium Chloride, Monopotassium Phosphate, Dipotassium Phosphate, Ammonium Nitrate, and Ferric Chloride. Or if you can see it better in terms of elements (Mg, S, O, Ca, Cl, K, N, H, Fe). You will notice that there is one KEY element missing from this solution, Carbon. Well lucky for us plastic is made up of Carbon (and Hydrogen) in long chains. Since Carbon is absolutely essential for microbes to grow (and all known life really) I was hoping that with all the other necessary ingredients available to them the microbes would use the Carbon found on the plastic to grow and luckily I was correct. So I will show you in just a few really simple steps how you can find plastic degrading bacteria from soil (I used landfill soil but I believe any soil would work).

Currently I am working on becoming a teacher and it is my personal belief that publishing this research for profit would really defeat the purpose.This would take away access to most people (who would have to fork over some serious cash just to look at it), especially when this could make a real, noticeable difference for a real environmental problem we face today. So I invite you to perform this experiment on your own, see what kind of results you get and collaborate our results. Please leave feedback for me in the comments, because this is my first instructable and I would like to make it the best it could possibly be. Thanks :)

Step 1: Materials

First you need your materials:
- At least 1 empty 2 liter Soda Bottle (cut the top off, see pictures below. I used 4)
- Bushnell Hass Broth (http://www.sigmaaldrich.com/catalog/product/FLUKA/B5051?lang=en&region=US)
- Soil (try to dig down a few feet for a better chance of finding anaerobic bacteria)
- An accurate scale (preferably accurate to the thousand ex: 2.008g)
- Cut up strips of plastic bags  
- Petri dishes and agar (I used TSA, Oatmeal agar, and Czapek agar just to have a nice variety)
- Autoclave
- Sealable test tubes
- Sterile gloves
- Bunsen Burner
- Tweezers 
- Inoculating Loop

<p>this is helpful for my research and experiment. thank you</p>
<p>Is anyone doing this type of project on a larger scale? I'm pretty sure that if it does work someone will find a way to capitalize on it. I'm a little concerned about the end result whereby a lot of anaerobic bacteria is unleashed. Any thoughts?</p>
<p>Anthrax exists naturally in most soil too, just don't come in contact with concentrates</p>
<p>Well I hope that this kind of project can be done on a larger scale, but that has yet to be seen. Based on how I set up the experiment all of the anaerobic bacteria is the experiment are naturally found in soil. All you do is provide them with an environment to grow up to larger numbers, but since these are naturally occurring there shouldn't be any issues if they were &quot;unleashed&quot; as you described it. </p>
<p>Great Experimental work :-)</p><p>Good idea to use landfill soil, successful micro-organisms would already be tolerant for toxins / harsh environments.</p><p>However has anyone stopped to consider that we ourselves consist of about 18% Carbon, the second most plentiful element in the body. And as stated the adaptive ability of micro-organisms (and the rate at which generations progress) such Carbon hunting Bacteria may adapt to using us as a source, especially as we would provide a better source of all round nutrients and a warm environment. - and to those who say 'then why hasn't that already happened' - the answer is that the bacteria have not been required to find a new sources (of Carbon) due to the abundance already available in nature.</p>
<p>I tried this with a ph paper but it was too difficult to read the intervals. I had to buy a brand new ph meter. Then dilute the sample of bacteria by 1:1000. Then for precautions clean the ph probe with 0.1% bleach or 0.05% sodium dichloroisocyanurate solution. Ph probe due the build up of protein requires 1g pepsin in 100 ml of 0.1% Hydrochloric acid.</p>
<p>They are both kept at 10 degrees C to prevent abnormal growth and to slow down growth. At room temperature they will be tested again. Pehaps cold temperature and chemicals may have an effect???</p>
<p>Hi I have been testing my samples and the one with cobalt salts have a constant ph of 6.5 for 2 days while the Chromium salts Cr3+ are less effective and the ph goes from 6.5 to 6.0 in two days. These are still a bit premature to make an conclusion but it sounds good to me. (This is for resistance or death of bacillus reuteni bacteria).</p>
<p>I am thinking of getting a 100 ul pipette so 0.1 ml /100 ml of sample (for diluting solution of metal salt with bacteria could be measured with a ph meter.</p><p>Error 0.1 ml/100 ml * 100% = 0.1%</p><p>If you don't care that much about accuracy and just want ball park range then 0.5 ml in 100 ml will do.</p><p>Error = 0.5%!</p>
<p>Another option is to make Potassium or Sodium aluminate by reacting Aluminum with either sodium or potassium hydroxide. Then you can see if the aluminum complex and lye are effective to kill bacteria or will the bacteria build up tolerance.</p>
<p>I am think of adding 1 ml of sugar solution diluting it by 200 ml of water to dilute the ph reading. </p><p>Then use the amplified ph H+ concentration and amplify it by 200. This may work too.</p><p>Example ph 8</p><p>H+ = 10^-8. * 200 = 2*10^-6.</p><p>ph of 2.00*10^-6 = 5.69!</p><p>Daniel Out..</p>
<p>I think that you could test the sugar solutions if it is possible to filter bacteria and sugars from samples. This would make it more accurate for use of a pH meter.</p><p>Sticky solutions can destroy a ph meter (Even good ones) quickly that is why I use percison ph paper as an alternative. </p>
<p>I took bacteria (I found lactobacillus Reuteri) and I am growing them in a medium beef ox extract with 5 ml of the following chemicals: Copper ammonia sulfate, Cobalt ammonia chloride, Chromium ammonia chloride, and Zinc ammonia hydroxide. </p><p>Warning:</p><p>Both Cobalt and Chromium compounds may be carcinogenic with prolonged exposure ,so handle them with the proper PPE. Copper and zinc compounds are corrosive and may cause burns with skin and eyes. All the chemicals I use here are corrosive.</p><p>1 M ammonia hydroxide is added to cobalt chloride, copper sulfate, zinc sulfate, and chromium chloride.</p>
<p>Hey thanks for the comment. It seems like this experiment you are describing is more about metal tolerance of your Lactobacillus. Is there a link from what you have done to what I did? Thanks!</p>
<p>hello! i'm so glad to have found this page! i wanted make a microbial fuel cell using plastic degrading bacteria but i can't find any anaerobic plastic degrading bacteria, that is, until i found this page! thank you very much for sharing :D</p>
<p>Glad you came across the page! Where are you doing this research?</p>
<p>this is helpful for my research and experiment. thank you</p>
<p>Thank you! What is your research?</p>
<p>I forgot to mention that accurate ph paper 0-13 intervals of 0.5 ph will be used to determine the concentration of ammonia salt and too see if an acid from the sugar Glucose is produced. The level of salt may slow down the process. </p>
<p>this is helpful for my research and experiment. thank you</p>
<p>this is helpful for my research and experiment. thank you</p>
<p>this is helpful for my research and experiment. thank you</p>
<p>this is helpful for my research and experiment. thank you</p>
<p>Greetings! This is an excellent article and ties well with my project in Uganda. <br><br>I just have two quick questions, the first might answer the second.<br>Firstly, I am not a scientist of any sorts, so if these questions seem like the answers are obvious, please excuse my ignorance. What I AM good at is asking questions until I overstand. I'm just a simple grassroots organizer, searching for possibilities to the scourge of plastic on our environment. <br><br>Question One: When the plastics have been broken down, does the remnant lose its toxicity? As in, will this byproduct be safe for the environment? How should one go about putting it to use? Can we dump it close to areas we are farming in and not have to worry about any toxic compounds entering into our food source?<br><br>Question Two: We are looking at TONS of plastic in Uganda. How easy would it be to upscale this system? Would a simple ratio increase work or is it more complex than that? <br><br>I can be emailed with details at dreadymayer@hotmail.com<br><br>You can find our project on facebook at &quot;zuukuka!&quot;, which is the umbrella organization, and the actual project is called &quot;Projekt Cavella&quot;. (Cavella is the local name for plastic bags here.)<br><br>Much appreciation for the free spreading of knowledge. If everyone had such a mentality, the world would be much different. <br><br>Bless,<br>DreadyBear</p>
<p>Great work, this is really cool! Do you have any updates of your own or from people who have contacted you about their own research?</p>
<p>Thank you so much! Unfortunately I never got a chance to continue this research in any capacity but quite a few people have talked to me about trying it themselves. However, most haven't gotten back to me after their initial contact. Hopefully that changes at some point but I am just glad so many people have read about this experiment, over 26k now...so crazy!</p>
<p>hello sir. I am a student of msc microbiolgy. And i am very interested in this plastic degradable microbes. If i get chance i will do this expwriment. Thanks for your update. If i have getting prblem i will contact you. And salute for your nice job ...</p>
<p>Hey. thanks a lot! It's great to hear that you will be giving this experiment a try. I wish you the best of luck and let me know if there is any way I can help!</p>
<p>Did this in college as well; got some cool SEM images of it, too!</p>
<p>Hey thanks for the comment. Sorry for the ridiculous response time, but any chance you still have those images? I would be interested to see what they look like!</p>
<p>block bacteria!</p>
hey ryan, Nice experiment. I am going to try this experiment and was wondering when you put in the plastic. Did you put in inside the soil or just on the soil so it can be exposed to the layer of broth?
<p>Thank you! Sorry for such a late reply....hopefully my answer isn't too late! To answer your question I first added the broth to the column and then completely put the plastic bags into the soil. Some of the bags just happened to be part way in the soil and part way in the broth. However, all of the bags had access to the broth because the soil was completely saturated with the broth. Hope that helps!</p>
I was wondering if the % of degradation for the plastic strips may have been affected by the fact that it was being tested in plastic containers. I'm no microbiologist but I was just wondering<br> <br> <br> Thanks!
<p>Hello! Thanks for the comment. Sorry about such a late response! I think the % degradation of the plastic bags was independent of the plastic container. Any bacteria growing on the plastic bags probably wouldn't have been affected by the container (plastic or glass or whatever). I think at least :)</p>
hey ryan i like ur idea very much <br>so i m going to try ur idea for making fuel <br>if u have any suggesstion let me know <br>thanks
Thank you very much. If you can isolate some bacteria then you might be able to mess with their DNA. It might be beneficial to look into some information about bacteria being used to create fuel, and then applying that to the bacteria you isolate from this experiment.
hi im a master microbiology student.im totally interested in your research..whats about your new projects regarding this research? have any new more advanced ideas regarding plastic degradation.
Thank you very much! Unfortunately I have not been able to repeat this experiment or start any new ones :( I still think that you could construct an anaerobic fuel cell with plastic, but you would first need to do this experiment first to get the isolates. What do you plan on doing?
Hey, I'm doing this project for my school project and is there a contact ID where I can contact you about the results?
Sure no problem, what level of school are you in currently? You can contact me through a message on here or my email, rch121@gmail.com
hey rch121 <br>I am a biotech master student n wana try tis experiment thankz 4 postin it will contact u if i will need ur help n will surely tell u the results
Awesome, good luck and I look forward to hearing from you.
Thank you so much. I loved reading this and following your thought process. I am a microbiologist too! I am more focused on the clinical side though. I just finished my undergrad and other than the job searching I caught up on reading books I never got to read during college. Basically I am just recollecting myself. I am impressed with your ambition and thoughts. Good luck and keep nurturing your brilliant mind. :)
Thank you very much, and Im glad you enjoyed it! Good luck on the job search!
This is awesome! How do you think using plastic bottles as your container medium affect the plastic degrading microbes in the experiment? Is the soda bottle plastic more stable (longer carbon chains) than the plastic bags used? Do you think if you kept it long enough the soda bottle would thin out over time?
Thank you! I think using the plastic bottles would work. I don't know for a fact if the carbon chain is longer but I assume since the material is stronger and more rigid that is the case. In fact I could do the exact same experiment but weigh the plastic bottles before and after a given amount of time. I would hypothesize that the plastic would indeed lose weight and if thats the case I would expect the bottle to thin over time.
Low Density Polyethylene or LDPE (plastic bags) and PET (bottles) are distinct polymers, arranged quite different, so even that most of the monomers of plastics are made of Carbon and Hydrogen, they behave in distinct forms. PETE would be quite hard to break into smaller chains from my experience. Of course, I understand plastics on a industrial basis, and have a shallow knowledge regarding molecular behavior of polymers, specially if there is bacterias involved. <br> <br>My 2 cents are that probably you need to test on different materials. It's a shame you lost your specimens. This is something quite important for the future.

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