DESTROYING the DNA of bacteria in
fecal samples using household products.


A human fecal sample contains a diverse makeup of bacteria, which has been shown to be fairly unique to the donor. The goal of this experiment was to destroy the DNA from the bacteria found in a human fecal sample using household cleaning products. If an individual wanted to insure their privacy on a biological level, could they use DIY methods for wiping out any traces of bacteria found in their feces?

Three people donated six fecal samples each, which were treated with:


1. Microwave: 3 minutes on high
2. Alcohol
3. Peroxide
4. Aceton
5. Ammonia
6. Bleach


The hope was for all of the samples to essentially look the same after being treated with household products.




The most effective household product in eliminating traces of bacteria DNA was peroxide. As an extremely aggressive molecule, peroxide is corrosive and can even be capable of mutating DNA. The peroxide-treated samples from donors B and C have a bacteria composition that differs significantly from the other treated samples.


Acetate and alcohol both interfered with the DNA extraction method used in the lab. Thus, no DNA from bacteria was able to be identified in these samples. In some ways, this is also a successful way of protecting your biological privacy, however there are other methods of DNA extraction that could still be used to identify the bacteria.



This tree shows the relationships between the 18 treated fecal samples. Seven of the samples were not able to be processed. The image shows how similar in composition the remaining eleven samples were to each other.



This graph shows the abundance of the top 30 most prevalent bacteria in the treated samples.