The U.S. Department of Energy’s Brookhaven National Laboratory and their Belgium colleagues at Hasselt University have identified plant-associated microbes that can improve plant growth on marginal land. Brookhaven biologist and lead author Daniel (Niels) van der Lelie, leads the Lab’s biofuels research program and says, “Biofuels are receiving increased attention as one strategy for addressing the dwindling supplies, high costs, and environmental consequences of fossil fuels. But competition with agricultural resources is an important socioeconomic concern.”

This research is another step forward in plant science and agronomy. Some readers will recognize a strong similarity to the Nitragin’s Optimize product for soybeans to this research on plants for fuel. Legume plants like soybeans have bacteria in symbiosis that fix nitrogen for assisting plant growth in concert with the genes that make use of the plant and bacterial paring.

What’s different is that this research is endophytic, or about microorganisms that live within that plant rather than outside. It a more advanced field of research in the early stages. Van der Lelie’s team has experience with plants growing on extremely marginal soil, particularly soils contaminated with heavy metals and other industrial chemicals. In prior research, his group incorporated the molecular “machinery” used by bacteria that degrade such contaminants into microbes that normally colonize poplar trees, and used the trees to clean up the soil. An added benefit, the scientists observed, was that the microbe-supplemented trees grew faster — even when no contaminants were present. That is the major clue.

Co-author Safiyh Taghavi says, “This work led to our current search for bacteria and the metabolic pathways within them that increase biomass and carbon sequestration in poplar trees growing on marginal soils, with the goal of further improving poplar for biofuel production on non-agricultural lands.” In the current study, the scientists isolated bacteria normally resident in poplar and willow roots known as endophytic bacteria, and tested selected strains’ abilities to increase poplar growth in a controlled greenhouse environment. They also sequenced the genes from four selected bacterial species and screened them for the production of plant-growth promoting enzymes, hormones, and other metabolic factors that might help explain how the bacteria improve plant growth. “Understanding such microbial-plant interactions may yield ways to further increase biomass,” van der Lelie said.

The scientists identified 78 bacterial endophytes from poplar and willow. Some species had beneficial effects on plant growth, others had no effect, and some resulted in decreased growth. In particular, poplar cuttings inoculated with Enterobacter sp. 638 and Burkholderia cepacia BU72 repeatedly showed the highest increase in biomass production — up to 50 percent — as compared with non-inoculated control plants. When it comes to growing biomass 50% is a very big improvement. It also leads one to wonder what other plants can benefit from this research field.

The Brookhaven press release is this link, with a video that isn’t set up to be embedded elsewhere. For the published paper abstract published in the February 1, 2009 issue of Applied and Environmental Microbiology click this link.

Now with a new level of plant research with good expectations for increasing biomatter the need to economically convert cellulose, hemicellulose and lignin into fermentable sugars before they can be turned into biofuel is an important issue.

Michigan State University’s Bruce Dale, University Distinguished Professor of Chemical Engineering and Materials Science has patented a process to pretreat corn-crop waste before conversion into ethanol, which means extra nutrients don’t have to be added, cutting the cost of making biofuels from cellulose. Called the AFEX (ammonia fiber expansion) pretreatment process, it uses ammonia to make the breakdown of cellulose and hemicellulose in plants 75 percent more efficient than when conventional enzymes alone are used.

Dale says, “Currently, pretreating cellulose with acid is a common way to break the material down into fermentable sugars. But after acid pretreatment, the resulting material must be washed and detoxified. That removes nutrients, leading to the mistaken idea that crop waste lacks the necessary nutrients. Doctoral student Ming Lau and I have shown that it’s possible to use AFEX to pretreat corn stover (cobs, stalks and leaves) and then hydrolyze and ferment it to commercially relevant levels of ethanol without adding nutrients to the stover. It’s always been assumed that agricultural residues such as corn stover didn’t have enough nutrients to support fermentation. We have shown this isn’t so.”

Cellulosic material pretreated with the AFEX process doesn’t have to be washed or detoxified, allowing ethanol to be created from cellulose without added nutrients or other steps, skipping three expensive process steps. Dale says, “Breaking down cellulose into fermentable sugars cost effectively has been a major issue slowing cellulosic ethanol production. Using AFEX as the pretreatment process can dramatically reduce the cost of making biofuels from cellulose.”

The research is published in the current issue of the Proceedings of the National Academy of Sciences.

Dale also said that, “There are several companies – including the Mascoma Corp., which plans to open one of the nation’s first cellulosic ethanol plants here in Michigan – that may be interested in using this technology. We are working to make the AFEX technology fit these companies’ needs.” Most likely is a pilot plant perhaps with MBI International, a subsidiary of the Michigan State University Foundation who partners with universities and companies to commercialize technology.

It’s been a good week for ethanol. A new fuel cell catalyst, a new technology to increase the biomatter potential and a much less expensive way to prepare the cellulosic materials to ready for conversion to sugars. Ethanol is finally looking more modern than just fermenting for motor fuel.


3 Comments so far

  1. More Food and Fuel Boosting and a Better Processing Technique b…/b : Science and Technology News on January 30, 2009 4:07 AM

    […] More here: More Food and Fuel Boosting and a Better Processing Technique b…/b […]

  2. Matt on January 30, 2009 1:57 PM

    Much ado about nothing. Blue green algae extracts and microbes were tested at Texas A&M as far back as the 60’s. They found that microbial enhanced soil produced more – and allowed for production on marginal (high salinity) fields.

  3. Joyce on February 6, 2011 1:47 PM

    This is very interesting, You’re an overly professional blogger. I’ve joined your rss feed and look forward to more of your wonderful posts. Additionally, I’ve shared your web site in my social networks!

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