Research presents potential for use of yeast as an environmentally-sustainable resource


Sarah Montgomery

Assisstant professor Hal Alper examines equiptment being cleaned. The instruments were recently used in the process of creating biofuels from genetically modified yeast cells and sugar.

Nicole Bueno

UT scientists have developed an environmentally friendly alternative to biodiesel, using yeast and ordinary table sugar.

The oils can be used in numerous everyday products, including biodiesel, plastics and waxes, said Hal Alper, an assistant chemical engineering professor working on the research.

“[Alper’s] innovative work with undergraduate and graduate students [is] developing sustainable energy platforms through tools like metabolic engineering, synthetic biology and evolutionary strategies,” said Tom Truskett, professor and chairman of the chemical engineering department.

The team has used simple sugar to create a platform for use in petroleum-based products, Alper said. Through a fermentation process, chemically harvested yeast cells are rewired to increase oil production from 10 percent to 90 percent. This is the highest level of lipid concentration recorded so far, making the extraction of these oils an economical option for the first time.

Today, environmentally friendly biodiesel is mainly harvested from soybean oil. After nearly five years, Alper and his team of seven other researchers developed a process in which the yeast cells take on a similar composition and serve as a more viable option for fuel.

“Plant growth is much more slow and seasonal than microbial growth,” said Andrew Hill, a chemical engineering graduate student who worked for nearly two years on the project.

If found successful as a fuel source, the lipids could be produced in factories within the U.S., and maximization of the process on a large scale could potentially lessen foreign oil imports, Alper said. Despite the potential of the use of lipids in the biodiesel industry, Alper said there are many more avenues to explore.

“Our petroleum dependency is about more than just our liquid transportation fuels,” Alper said.

Alper said he hopes to discover new substitutes for table sugar in the yeast fermentation process. In the meantime, he is working to continue to beat his previous record of lipid concentration, and, since the publication of his study, already has.

While there has been no testing on the longevity or the exact economic benefit of the potential biofuel alternative, Alper and his team said they believe the environmental impact is significant.

“At the rate society is consuming these limited resources, we need a sustainable way to produce things like biofuels and plastics,” Hill said. “[This project] is just one aspect of what needs to be done.”