Making Biofuels from Panda... What?

Dec 19, 2013

As one of the Memphis Zoo's two giant pandas, Ya Ya always attracts a big crowd. Now she's helping researchers at Mississippi State University produce a next-generation biofuel.
Credit The Memphis Zoo

The Memphis Zoo got a new ten-year lease on two giant pandas. Meanwhile, researchers got a new lease on finding a new source of fuel. Hint: it starts out as bamboo.

For centuries, scientists spent their lives searching for the philosopher’s stone, a mythical substance that could transform base metals into gold. These days, biofuels researchers have set their sights on a new philosopher’s stone: a chemical process that can turn plant waste—things like corn husks and wood chips—into ethanol, a biofuel.

Their search has led them to some pretty weird places. Think camel stomachs and turkey tail fungus. But perhaps the weirdest research is currently being conducted at Mississippi State University. To tell you more about it, here’s biofuels enthusiast Jay Leno.

You heard the man. Panda poo. Although… Leno didn’t quite get it right. Like just about everybody else, biofuels researchers don’t have much use for smelly, half-digested bamboo. We certainly won’t be using it to power our cars anytime soon. No, what scientists want is what’s inside those little green piles: a cornucopia of bodacious, plant-digesting bacteria. 

Dr. Ashli Brown is a biochemist who leads the research team at Mississippi State University.
Credit John Minervini

“What we’re looking at,” says Dr. Ashli Brown, a biochemist who leads the research team at Mississippi State, “is really identifying the bugs -- the microbes -- that are in the gut of these pandas. We’re taking those microbes; we’re cultivating them. We’re tweaking the conditions to then get them to produce oils that can be used to produce a next-generation biofuel.”

The problem facing researchers like Dr. Brown is one of efficiency. Right now you have to burn about a gallon of gas to get a gallon of ethanol from plant waste. If cellulosic ethanol is ever going to be a sustainable fuel source, that number has to come down.  So Dr. Brown and her team asked themselves, what in nature is really good at turning green plants into energy? And then it hit them.

“The Giant Panda has a simple digestive tract,” Dr. Brown says. “It’s short, and because the woody material is not in the digestive tract for very long, these bacteria have to be really efficient and quick at what they do. So that’s what we’re honing in on. We’re honing in on the skills of this bacteria to be really quick and really efficient at breaking that material down.”

When I visit the China Exhibit at the Memphis Zoo, Ya Ya is lounging around on a giant wooden play structure. 

As one of the Memphis Zoo’s two giant pandas, Ya Ya can eat up to 40 pounds of bamboo in a single day. And according to Andy Kouba, the zoo’s Conservation Director, the research material is literally piling up.

“They go pretty frequently,” laughs Kouba. “If you can imagine, they’re eating 17-20 kilograms of bamboo in a day, so they’re pooping quite frequently. Sometimes every couple minutes, sometimes you’ll have multiple fecal boli come out at one time. So yeah, they are pooping machines.”

These images--taken using an electron microscope--show bacteria from a panda's digestive tract. Dr. Brown and her team want to use such microbes to produce cheap ethanol on a large scale.
Credit Dr. Ashli Brown

So how about that panda poo? What’s it like?

“It’s a very round, oblong structure,” says Kouba. “It actually sometimes comes out smelling like grass or bamboo. If I had to describe all of the different fecals that we work with here, it’s actually one of the more pleasant ones. So yeah, it kinda smells like wet grass.”

Once it arrives at the lab, the panda poo is separated and analyzed using a variety of high-powered equipment. The research is still in an early stage, but the eventual goal is to use these bacteria to produce cheap ethanol on a large scale. So is this the new philosopher’s stone? Has the research team at Mississippi State struck gold? Well, says Dr. Brown, gold is nice, but what’s even nicer is learning to power our nation with renewable fuel.

“So I think the big picture,” says Dr. Brown, “is really starting with the idea of conservation. I think that’s important. And with this project, if you can take two waste streams—the waste of an endangered animal and agricultural waste—and you can put them together, and you can make fuel for a nation… I think that’s a really good thing.”

John Klyce Minervini is a writer who lives in Memphis and Portland.