Giant pandas could one day fuel cars and advance the development of bio-fuels - owing to microbes found in their faeces.
Giant pandas Ya Ya and Le Le in the Memphis Zoo are making contributions toward shifting production of bio-fuels away from corn and other food crops and towards corn cobs, stalks and other non-food plant material.
"We have discovered microbes in panda feces might actually be a solution to the search for sustainable new sources of energy," said Ashli Brown, who heads the study.
Brown and her students, based at Mississippi State University, now have identified more than 40 microbes living in the guts of giant pandas at the Memphis Zoo that could make bio-fuel production from plant waste easier and cheaper.
The research also may provide important new information for keeping giant pandas healthy, Brown added.
Ethanol made from corn is the most common alternative fuel in the US. However, it has fostered concerns that wide use of corn, soybeans and other food crops for fuel production may raise food prices or lead to shortages of food.
Brown pointed out that corn stalks, corn cobs and other plant material not used for food production would be better sources of ethanol.
However, that currently requires special processing to break down the tough lignocellulose material in plant waste and other crops.
Breaking down this material is costly and requires a pre-treatment step using heat and high pressure or acids.
Not only do pandas digest a diet of bamboo, but have a short digestive tract that requires bacteria with unusually potent enzymes for breaking down lignocellulose.
"The time from eating to defecation is comparatively short in the panda, so their microbes have to be very efficient to get nutritional value out of the bamboo," Brown said.
"And efficiency is key when it comes to bio-fuel production - that's why we focused on the microbes in the giant panda," said Brown.
Working with scientists at the University of Wisconsin-Madison, Brown's team identified bacteria that break down lignocellulose into simple sugars, which can be fermented into bioethanol.
They also found bacteria that can take those sugars and transform them into oils and fats for biodiesel production.
Brown said that either the bacteria themselves or the enzymes in them that actually do the work could be part of the industrial process.
