"Corn-based ethanol production in the United States currently is about 3 billion gallons per year," Ho said. "According to conservative estimates, 30 percent of the residue left behind in the cornfield after harvest could produce another 4 billion to 5 billion gallons annually.
"The use of cellulosic materials also could open up new markets for crops such as grasses, which can be grown on marginal lands, creating jobs and providing more energy independence."
An added advantage of yeast strains developed by Ho is that they are based on environmentally safe Saccharomyces yeast, which has been used for centuries to make wine and bread and is the only microorganism used by industry for large-scale ethanol production from glucose.
Ho has worked for 20 years to produce and perfect a yeast that can effectively convert more of the sugars in plant matter - corn stalks, tree leaves, wood chips, grass clippings, and even cardboard - into ethanol.
"Ethanol produced from cellulosic materials is an ideal, domestically available fuel," Ho said.
In 1993, Ho's group became the first in the world to produce a genetically engineered Saccharomyces yeast that can effectively ferment both glucose and xylose.