Scientists uncover new source for biofuels

Washington, April 24 : American scientists have discovered that a newly created microbe produces cellulose and sugars, which can be converted into ethanol and other biofuels so as to significantly satiate the demand of transportation fuel. A study report from The University of Texas at Austin says that the cyanobacteria developed by Professor R. Malcolm Brown Jr. and Dr. David Nobles Jr. secrete simple sugars like glucose and sucrose, which are the major sources used to produce ethanol.

"The cyanobacterium is potentially a very inexpensive source for sugars to use for ethanol and designer fuels," says Nobles, a research associate in the Section of Microbiology and Molecular Genetics.

The researcher duo says that the cyanobacteria, also known as blue-green algae, can be grown in production facilities on non-agricultural lands using salty water unsuitable for human consumption or crops.

The research team says that glucose, cellulose, and sucrose can be continually harvested without harming or destroying the cyanobacteria, which is an important finding because harvesting cellulose and sugars from true algae or crops like corn and sugarcane requires killing the organisms.

Reporting their finding sin the journal Cellulose, the researchers revealed that cyanobacteria that can fix atmospheric nitrogen can be grown without petroleum-based fertilizer input.

Nobles made the new cyanobacteria by giving them a set of cellulose-making genes from a non-photosynthetic "vinegar" bacterium, Acetobacter xylinum, well known as a prolific cellulose producer.

He said that the new cyanobacteria produce a relatively pure, gel-like form of cellulose that could be broken down easily into glucose.

"The problem with cellulose harvested from plants is that it's difficult to break down because it's highly crystalline and mixed with lignins (for structure) and other compounds," Nobles said.

He said that he was surprised to see that the cyanobacteria also secrete large amounts of glucose or sucrose, sugars that can be directly harvested from the organisms.

"The huge expense in making cellulosic ethanol and biofuels is in using enzymes and mechanical methods to break cellulose down. Using the cyanobacteria escapes these expensive processes," said Nobles.

Brown believes that using cyanobacteria to produce ethanol will lead to a significant reduction in the amount of arable land turned over to fuel production, and decrease pressure on forests.

"The pressure is on all these corn farmers to produce corn for non-food sources. That same demand, for sucrose, is now being put on Brazil to open up more of the Amazon rainforest to produce more sugarcane for our growing energy needs. We don't want to do that. You'll never get the forests back," says Brown, the Johnson and Johnson Centennial Chair in Plant Cell Biology.

Cyanobacteria are just one of many potential solutions for renewable energy, says Brown.

"There will be many avenues to become completely energy independent, and we want to be part of the overall effort. Petroleum is a precious commodity. We should be using it to make useful products, not just burning it and turning it into carbon dioxide," the researcher adds.

ANI