Well, the fungi "breaks down plastic", which means that it converts it into other types of molecules. Just plants use C02 + H20 + sunlight in photosynthesis to

Well, the fungi "breaks down plastic", which means that it converts it into other types of molecules. Just plants use C02 + H20 + sunlight in photosynthesis to convert it into O2 + glucose. If we could break down the molecules ourselves we would have done it already, but it's not easy to do that. That is why we benefit from these natural occurring organisms that break them down and leave a more useful byproduct (to us). Although nano technology can eventually give us the ability to do this in a controlled way.