The Institute for Sustainable and Renewable Resources, in Danville, Va., is studying the potential to use the Jerusalem artichoke (Helianthus tuberosis), a perennial native sunflower species, as a feedstock for producing ethanol.
The institute is a research center jointly affiliated with the departments of horticulture and forestry at Virginia Polytechnic Institute and State University (Virginia Tech) (http://www.vt.edu) that’s focused on developing new opportunities for farming communities affected by declining tobacco and textile markets.
The Jerusalem artichoke grows from tubers and produces inulin, a fructose polymer. The plant stores the inulin in its stem until it flowers, when the inulin is then translocated to the tuber. “The plant grows like a weed,” said Dr. M. Javed Iqbal, a researcher at the Institute for Sustainable and Renewable Resources. “Even if you harvest most of the tubers, there will still be one left that will grow back again. It's kind of a nuisance in the Upper Midwest, because it's hard to get rid of, which leads to one of the problems, actually: It grows so thick that you sometimes have to thin it.”
Iqbal said Native Americans used Jerusalem artichoke tubers as food. Settlers brought the tuber back to Europe and today, scientists in Spain are looking at the plant as a feedstock for ethanol production. Iqbal said Chinese researchers are also looking at the feedstock. “There is a good amount of research going on (for) producing ethanol from the Jerusalem artichoke,” he said, “but unfortunately, not in the U.S.—other than me.” Iqbal laughed. “I don't know why people aren't interested in using it. Everybody is after switchgrass. There is nothing wrong with that, but we need to have alternative feedstocks, also.”
To improve the Jerusalem artichoke’s potential as a feedstock for ethanol, Iqbal said the institute is identifying the genes that regulate flowering and the translocation of sugars in the plant. The institute plans to modify the genes to prolong the growing season, increase sugar production, and delay the translocation of sugars.
Iqbal said because of the sugar that’s produced is inulin, the Jerusalem artichoke might also be harvested to produce high fructose syrup, displacing the need for corn starch.
Currently, the institute is growing 23 varieties of Jerusalem artichoke growing the plant in a one-acre plot; some of the varieties can grow to be two meters high, Iqbal said. He said the institute’s goal is to build a pilot-scale biorefinery to produce ethanol from the plant.
“We need to make people aware that there are a lot of alternative feedstocks, “Iqbal said. “There are other crops (besides corn) that are ready to be used. The Jerusalem artichoke is going to be one of them.”
Via Ethanol Producer Magazine