Biofuel production still has some obstacles before it begins powering our daily lives. The main issue is contamination from a variety of sources, and a little bit of biological engineering aims to reduce the need for filtering.
To make a batch of biofuel plant matter and specific bacteria and yeasts are mixed together, then held in favorable conditions so that the microbes can eat the starch molecules and excrete a substance we can burn. One hang up with this process is that a whole plethora of microbes are capable of digesting the raw plant matter, yet only a small portion of them create fuels for us to burn.
If fuel-making microbes can eat the food source, so can other bacteria or yeast. When other microbes start growing, they reduce the efficiency of the process.
Sterilization is nothing new to production facilities, but to reach the purity required for use, a large amount of energy will be required to sterilize a production-sized batch. Another option is to add antibiotics to control the unintended additions. Unfortunately the remaining materials after fuel is extracted is exported to feed livestock and would increase the likelihood of drug resistant bacteria in the future. So in lieu of these methods a bit of engineering of the biological persuasion will give the proper microbes a fighting chance.
By manipulating the abilities of the bacteria and yeast into super-powered forms, scientists were able to get the microbes to digest non-natural materials for biofuels. In tests purposely contaminated with competing composting bacteria, the newly strengthened microbes were able to flourish naturally where other contaminating strains were severely hampered. The specifically engineered yeast and bacteria was able to out compete the other fauna, eventually starving them to extinction within the plant matter, leaving a purer form of biofuel.
Click here for the full article by Sam Lemonick.