A Possible Biofuel Breakthrough, Via The Leafcutter Ant

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For all of modern humanity’s technological prowess, the best chemistry lab on the planet is arguably still owned by mother nature. On Tuesday, Tim McDonnell at Mother Jones spotted work by researchers at the University of Wisconsin-Madison, among others, that may lead to a powerful new enzyme for producing cellulosic biofuels. And they did this by studying, of all things, leafcutter ants.

The thing about cellulosic biofuels is they’re produced from grass, wood chips, or other feed stocks that don’t double as food. More traditional biofuels, since they’re most often produced from corn, impinge on the food supply. The spike in corn demand — and thus the spike in corn price — that’s been fueled by America and European biofuel policies has arguably wrecked the food security of millions of poor people in developing countries around the world. And that’s on top the rising global food crisis from droughts and extreme weather driven by climate change.

But cellulosic biofuels remain an up-and-coming technology, with a commercial viability that’s far from certain. So big breaks in designing the enzymes and chemical processes is a big deal.

What Frank Aylward and his fellow researchers did was go down to Panama and Costa Rica to study how leafcutter ants produce their food. The insects literally cultivate a fungus in their underground nests that breaks down the bits of leaves they bring back. (The ants can collect half the weight of a cow in leaf material per colony every year.) Aylward and co. were able to isolate and identify the enzyme the fungus uses for this process, and realized it could be a powerful tool for biofuel production. As they told Mother Jones, the enzyme could even make biofuel out of the other parts of the corn stalk that don’t serve as food for humans:

For making fuel, Aylward asks, “why don’t we use the rest of the corn plant? It’s because the sugars are tied up in cellulose and other things that are hard to break down. So we’re looking for enzymes that can help.” Enzymes are already used for this purpose, and a crop of businesses have sprung up in the biofuel boom to manufacture them, but Aylward believes his could be among the most efficient ever discovered. And using every part of the corn plant, including parts that typically go to waste, could make ethanol production more sustainable and boost its climate benefits.

Obviously, if we can crack the chemistry for turning the rest of the corn stalk into biofuel, while leaving the cob itself as food, that might largely circumvent the food security problem. Beyond that, even the feedstocks for cellulosic biofuels have to be grown on cropland. That encourages deforestation, and as far as the simple math of carbon budgets go, naturally occurring forests and grasslands remove more carbon from the atmosphere than cropland. But if we can create cellulosic biofuel from land that’s already being used to grow food anyway, that could massively improve the quality of our land use.

Granted, biofuels are probably never going to be the biggest part of a renewable energy economy. But they will be a part, and this will be an exciting development if it pans out. Aylward told Mother Jones he’s already been approached by private firms interested in manufacturing the enzyme and starting work on biofuel production, so here’s to hoping.

12 Responses to A Possible Biofuel Breakthrough, Via The Leafcutter Ant

  1. Joan Savage says:

    Wood chips and grasses are forms of slow decaying organic matter that provide several of the components for fertile soil formation. As they decay, they add cation exchange capacity, needed for retention of soil nutrients. They help retain water, yet they also provide micro-structure to allow air flow.

    It’s a sad day to see that resource co-opted to make yet another fluid fuel for engines.

  2. Superman1 says:

    Another data point validating our unwillingness to make the harsh sacrifices required for avoiding the climate cliff.

  3. Gillian says:

    Yes, I support Joan’s comment. Corn stalks (and other crop stalks) are not currently ‘wasted’. They are used for animal feed or plowed-in to contribute to healthy soil.

    This new technology won’t use ‘waste’ materials, instead it will divert materials from their current use. Before going down this path someone needs to do a cost benefit analysis and put a value on the current use of the material so we can be clear about the best-value use.

  4. Merrelyn Emery says:

    Who knows what will be classified as ‘food’ in the future, could be a lot more than now, ME

  5. If the key issue surrounding climate change is the production of CO2 that adds to atmospheric greenhouse gases, how does creating biofuels solve this problem? It may be a solution for peak oil, but does nothing positive for our climate.

  6. KokoTheTalkingApe says:

    Yes, Joan and Gillian are right, corn stalks and other cellulosic material are not wasted currently. They do promote soil health.

    However, if they are turned into fuel, the vehicle is essentially doing what the microbes that normally consume cellulose would do in several intermediate steps: turning it into carbon dioxide and water, and extracting energy. That carbon dioxide in the air is still available to plants and bacteria to enrich the soil. The difference is that with cellulosic fuels, the carbon came from the air and returns to the air, while with fossil fuels, the carbon comes from deep underground and into the air. There is no reason why soils should become less fertile because we use renewable fuels.

  7. Adam R. says:

    It doesn’t take sequestered fossil carbon out of the ground and put it in the air. It recycles carbon that modern plants have used. Net carbon to the atmosphere is close to zero, so any fossil carbon it keeps underground is a win.

  8. Mulga Mumblebrain says:

    Soil fertility takes centuries to slowly build up, then we mine the soil in agribusiness and now we want to intercept the nutrient flow to make fuel. We are a determined lot, aren’t we, bent on self-destruction.

  9. Mulga Mumblebrain says:

    ‘Cost-benefit analyses’ are as reliable as ‘environmental impact studies’. That is they reliably, in fact invariably, discover that any capitalist enterprise is worth the effort, no matter how great the ‘externalities’ of environmental destruction, so long as the right people make money out of it.

  10. Mulga Mumblebrain says:

    There is a little more to soil fertility than CO2 and water alone.

  11. MightyDrunken says:

    The end products of the process could be used to fertilise soil. So there will be some loss but I wouldn’t expect it to be too different.

  12. There is only a limited amount of bio-fuel that can be produced without impacting on either food production or the environment in general. Woodchips, grass etc all imply the cutting down of trees and other damage to the natural environment.
    We are certainly not going to be able to produce enough low impact, renewable bio-fuels to replace petro-chemicals, provide the energy for long distance air/sea travel and other travel for which more direct use of clean energy is practical.
    Our best hope for meeting this shortfall are renewable, low impact transport fuels produced from nothing more than clean electricity, water and nitrogen or CO2. All this can be done using existing technology developed in the 19th and 20th centuries. For more see: