May 15, 2007, Updated September 13, 2012

Since the popularity of Al Gore’s documentary An Inconvenient Truth – one of the top-grossing documentaries in the United States – it has become clear that concern for global warming is widespread in America.

In his film, Gore predicts a series of catastrophes that would result from the continued progress of global warming, including the melting of massive glaciers in the Himalayas. Carbon emissions, produced by motor vehicles, are the leading cause of global warming, and the quest for alternative fuels is now a hot topic worldwide.

Israeli researcher Dr. Amir Sharon of Tel Aviv University is on the trail. Sharon has discovered a transgenic fungus strong enough to convert even the most resilient plant parts into bioethanol, a chemical used for biofuel. Strengthened with an anti-death gene, this fungus is resistant to harsh conditions such as heat and toxic substances – both of which are released while converting plant biomass into ethanol. As a result, the production of ethanol using this transgenic fungus could be much more efficient than with conventional fungi.

Biofuel – fuel derived from plant biomass – has emerged as one of the most viable alternatives to oil. The US bioethanol industry is booming. In 2006, 13% of the US corn crop was used for the production of ethanol.

But there are drawbacks to biofuel’s production – it is expensive and wasteful. Most bioethanol produced in the US is derived from the edible parts of corn crops. The stalks and leaves, comprised of cellulose and known to scientists as cellulosic biomass, are much harder to convert into ethanol. The cellulose is bound with a chemical called lignin, which causes the plant material to be rigid and difficult to break down. Consequently the production of bioethanol from cellulosic biomass is not carried out on an industrial scale in the US.

As a result, some grain crops that could be used for food production are being used for fuel production instead. The prevailing criticism is that there is not enough farmland to produce crops for biofuel and still maintain an adequate supply of food. Additionally, Americans consume about 400 million gallons of gasoline per day, and that figure is growing. Bioethanol only provides 70% of the energy contained in a tank of gasoline.

However, Sharon’s new fungus, with its capability to convert inedible plant cellulose into ethanol, could have a significant impact on ethanol production. According to Sharon, fungus is normally very difficult to culture.

“It is spoiled. Fungus needs very specific conditions in which to thrive. These transfungi are much more resistant to stress conditions, even oxidant chemicals like hydrogen peroxide or UV radiation, which usually harms the DNA and causes mutations, has little effect on the new transfungi,” he told ISRAEL21c.

How does this apply to the production of ethanol? Since fungi require specific conditions for survival, the stress conditions produced during the conversion process eventually kill the fungi.

“When you apply the fungus to the plant material, degradation will release heat and toxic material, which usually kills it. But this transgenic fungus is more tolerant so it can withstand heat and toxins, making the plant degradation process more efficient,” said Sharon.

Sharon discovered the unique properties of this fungus by accident. “We were exploring ways to modify the germination of the fungus using anti-death genes… about a year later when we went to clean out the cold room, we were astonished to discover a bright fungal colony that should have died months before.”

The unusual hardiness of the fungus may also be important for the food and drug industries, which rely on the process of fermentation. More than 20 drugs, including penicillin, require fungi in the manufacturing process. Sharon says, “Our fungus can grow for much longer in the fermenter – twice as long or more. This can allow for the production of many more fermentation units.” Doubling the efficiency of food and drug manufacture could mean significant cost savings for these industries.

According to David Zaks, an American expert on environmental issues who contributed to the popular website Worldchanging, Sharon’s research bodes well for future cellulose conversions.

“This research is definitely an important step in providing the technology needed to do [the conversion of cellulose] on a more industrial scale. In the future we’ll be able to do it with things like switchgrass,” Zaks told ISRAEL21c.

A graduate student of the University of Wisconsin, Madison at the Center for Sustainability and the Global Environment, Zaks predicts that cellulosic ethanol is going to be ‘the next big thing’. “There are many different small-scale production companies that are going to be working on it,” he explained. “There’s a lot of money being put into this field right now to make it an important part of our energy future.”

Sharon also sees biofuel as an important alternative to fossil fuels, both to prevent global warming and to supplement the world’s supply of fuels. “When we use plants [for biofuel] we’re not damaging the environment because we’re recycling carbon dioxide – releasing the same molecule that plants have already absorbed,” he said. “We also need alternatives because in 30 or 40 years we’ll have used up our supply of petrol.”

Irit Ben Chlouch, director of business development at Ramot, Tel Aviv University’s technology transfer company, realized the financial implications of Sharon’s findings. “Not even mentioning biofuels, the fungal biotechnology market which includes drugs, enzymes and the food market, is estimated at over $100 billion a year,” she said.

Ben Chlouch added that Ramot is in negotiations with several companies to develop and commercialize Sharon’s breakthrough technology. “We are not at liberty to disclose the names [of the companies] until a final agreement has been reached,” she said.

Sign up for the ISRAEL21c Newsletter

More on Environment

Fighting for Israel's truth

We cover what makes life in Israel so special — it's people. A non-profit organization, ISRAEL21c's team of journalists are committed to telling stories that humanize Israelis and show their positive impact on our world. You can bring these stories to life by making a donation of $6/month. 

Jason Harris

Jason Harris

Executive Director

Read more: