A 'bionic leaf' could help feed the world

April 3, 2017
The radishes on the right were grown with the help of a bionic leaf that produces fertilizer with bacteria, sunlight, water and air. Credit: Nocera lab, Harvard University

In the second half of the 20th century, the mass use of fertilizer was part of an agricultural boom called the "green revolution" that was largely credited with averting a global food crisis. Now, the challenge of feeding the world looms again as the population continues to balloon. To help spur the next agricultural revolution, researchers have invented a "bionic" leaf that uses bacteria, sunlight, water and air to make fertilizer in the very soil where crops are grown.

The team will present the work today at the 253rd National Meeting & Exposition of the American Chemical Society (ACS).

"When you have a large centralized process and a massive infrastructure, you can easily make and deliver fertilizer," Daniel Nocera, Ph.D., says. "But if I said that now you've got to do it in a village in India onsite with dirty water—forget it. Poorer countries in the emerging world don't always have the resources to do this. We should be thinking of a distributed system because that's where it's really needed."

The first "green revolution" in the 1960s saw the increased use of fertilizer on new varieties of rice and wheat, which helped double agricultural production. Although the transformation resulted in some serious environmental damage, it potentially saved millions of lives, particularly in Asia, according to the United Nations (U.N.) Food and Agriculture Organization. But the world's population continues to grow and is expected to swell by more than 2 billion people by 2050, with much of this growth occurring in some of the poorest countries, according to the U.N. Providing food for everyone will require a multi-pronged approach, but experts generally agree that one of the tactics will have to involve boosting crop yields to avoid clearing even more land for farming.

To contribute to the next , Nocera, who is at Harvard University, is building on the work he's most famous for—the artificial leaf—to make fertilizer. The artificial leaf is a device that, when exposed to sunlight, mimics a natural leaf by splitting water into hydrogen and oxygen. This led to the development of a bionic leaf that pairs the water-splitting catalyst with the bacteria Ralstonia eutropha, which consumes hydrogen and takes carbon dioxide out of the air to make liquid fuel. Last June, Nocera's team reported switching the device's nickel-molybdenum-zinc catalyst, which was poisonous to the microbes, with a bacteria-friendly alloy of cobalt and phosphorus. The new system provided biomass and yields that greatly exceeded that from natural photosynthesis.

"The fuels were just the first step," Nocera says. "Getting to that point showed that you can have a renewable chemical synthesis platform. Now we are demonstrating the generality of it by having another type of bacteria take nitrogen out of the atmosphere to make fertilizer."

For this application, Nocera's team has designed a system in which Xanthobacter bacteria fix hydrogen from the and from the atmosphere to make a bioplastic that the bacteria store inside themselves as fuel.

"I can then put the bug in the soil because it has already used the sunlight to make the bioplastic," Nocera says. "Then the bug pulls nitrogen from the air and uses the bioplastic, which is basically stored hydrogen, to drive the fixation cycle to make ammonia for fertilizing crops."

Nocera's lab has analyzed the amount of ammonia the system produces. But the real proof is in the radishes. The researchers have used their approach to grow five crop cycles. The vegetables receiving the bionic-leaf-derived fertilizer weigh 150 percent more than the control crops. The next step, Nocera says, is to boost throughput so that one day, farmers in India or sub-Saharan Africa can produce their own .

Explore further: Bionic leaf turns sunlight into liquid fuel

More information: Sustainable solar-to-fuels and solar-to-fertilizer production, the 253rd National Meeting & Exposition of the American Chemical Society (ACS), 2017.

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13 comments

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Shootist
1 / 5 (5) Apr 03, 2017
Grow more cows

Beef, Real Food For Real People®
RealityCheck
2.3 / 5 (3) Apr 03, 2017
Farmers been using LEGUMINOUS plants to do all that and more via Crop Rotation for reducing/preventing Insect/disease attacks/establishment, while providing FOOD and also the leftover BIOMASS/ROOTS to feed/condition the soil for following crops. How expensive is the 'patented bionic leaf' going to be? And how will the monopoly over same be good for those farmers who can't afford it? All this seems like a 'propriety solution' for a non-problem so that yet another multinational conglomerate can acquire the rights and screw/profiteer by convincing/forcing farmers into 'buying' something that is inferior to what they get for free now. Leguminous Plants ALREADY...
use bacteria, sunlight, water
...AND extract atmospheric CO2 as well as deeper/unused nutrients like phosphorus, calcium etc, to produce biologically active/balanced fertilizer, increase soil's organic matter content.

If "bionic leaf" ALSO produced ELECTRICITY cheaper than current methods they'd have something!
humy
5 / 5 (1) Apr 04, 2017
. How expensive is the 'patented bionic leaf' going to be?

RealityCheck

Just suppose it was made patented-free and given to the farmers for free for the benefit of the whole of humanity; would you have any objections to it then? Is the 'patent' the real and only reason for your protest? Because, if there is, there are obviously various political and economic solutions to that so that doesn't seem much of a reason for rejecting it.
humy
5 / 5 (1) Apr 04, 2017
missedit;

"Because, if there is,..."

should be;

"Because, if it is,..."
dustywells
5 / 5 (1) Apr 04, 2017
@RealityCheck
What is the point of expending effort and resources in research if we can not profit from our work? Patent protection and licensing fees are the means to recovering costs and to continuing research. Unit cost and patent protection are incidental and inconsequential once the initial process is viable.

As illustrated with renewable energy, widespread research of bionic chemical production will build on Nocera's invention, improve efficiency and reduce costs. The key to the application of the artificial leaf and its future enhancement is in the third paragraph and, like in RE, is spelled "distributed system."
RealityCheck
3 / 5 (4) Apr 05, 2017
Hi humy. :)
Just suppose it was made patented-free and given to the farmers for free for the benefit of the whole of humanity; would you have any objections to it then?
Not a one, mate! However, I am 67years old and have seen too much 'gaming' of the patents system by multinationals like Monsanto and Phizer etc to keep control of profitable (for them) patent rights. Even when they have expired they have made minor changes to the product which then enables them to claim new/extended patent monopoly.

Is the 'patent' the real and only reason for your protest?...that so that doesn't seem much of a reason for rejecting it.
Not at all. I also mentioned the economic feasibility even if technically feasible. I pointed out that the 'fertilizer' etc benefits are already more cheaply done with existing leguminous plants which do all that and more.

Also, if 'bionic leaf' can be adapted to produce cheaper electricity it would be great! Good luck to them, I say! :)
RealityCheck
3 / 5 (4) Apr 05, 2017
Hi dustywells. :)

Please first read my response/clarification to humy above. I again stress that the patent system is ok IF it is not captured by the multinationals who have profit(eering) as a 'business model' which many times goes against the interests of national/humanity interests/ethics. That was my only concern re the patenting aspect. The other concern was "why" a bionic leaf if that is more expensive/limited than what legumes do now even better all around the farming systems of the world, which even improves the soil etc as well as providing bio-active fertilizer without needing to pay a patent holder for the inferior 'technological alternative' to the better/cheaper natural legumes crop-rotation techniques available 'free' for millennia? The only reason I can see at present for further research/patent of a 'bionic leaf' is for cheaper/distributed electricity generation. That would be something to support, for sure! And more power to them! Cheers. :)
antialias_physorg
5 / 5 (3) Apr 05, 2017
What is the point of expending effort and resources in research if we can not profit from our work?

Ask the inventor of Penicilin that or the inventor of the world wide web who made their inventions patent-free on purpose. Profit ain't always dollars and cents - and not everyone is out to grab as much as they can.
'Value' is not the same as 'dollar value'.
Zzzzzzzz
5 / 5 (1) Apr 05, 2017
Guys - I have RC, DW, & the shitist of my ignore list. I'm trying to limit my exposure to fecal regurgitation.
RealityCheck
3.4 / 5 (5) Apr 05, 2017
@Zzzzzzzz.
Guys - I have RC, ...on my ignore list.
As far as me being on your 'list': that is your loss; and a great way for you to avoid/deny having to deal with information inconvenient to your personal ego-tripping way of doing science/humanity discourse. No wonder you miss a lot of the gems among the dross. Go back to sleep, "Zzzzzzzz"; your studied laziness/stupidity in pursuit of the objective science ideas/observations irrespective of source/person is telling: that scientific method principles of objectivity and respectful dialogue are strangers to you; preferring instead to join gangs and insult those whom you don't like (there are social media sites better suited to your type of silliness/laziness/malice, mate; go there to make your insulting arrogant malicious "fecal regurgitations", and leave PO discussions/threads/posters alone; and stop making 'lists' based on your own studied aversion to being informed irrespective of person/source informing you). Bye.
dustywells
not rated yet Apr 05, 2017
@antialias_physorg
What is the point of expending effort and resources in research if we can not profit from our work?

Ask the inventor of Penicilin that or the inventor of the world wide web who made their inventions patent-free on purpose. Profit ain't always dollars and cents - and not everyone is out to grab as much as they can.
'Value' is not the same as 'dollar value'.


It is true that profit is not always measured in dollars. If some inventors' profit is measured by feeling warm and fuzzy, all the more power to them, however, continued research may be costly and can be supported by licensing fees. Also, as RC points out, a patent can assure that the invention is not stolen by an opportunist or suppressed by multinationals whose products would be negatively impacted.
antialias_physorg
1 / 5 (1) Apr 06, 2017
however, continued research may be costly and can be supported by licensing fees.

Or you can just make a case for the importance of some research and do this via state sponsored funding. I think one can argue that paying more taxes for stuff like this - while on the other hand paying for the end product at a cost that doesn't include anyone profiting from it - is a lot cheaper to teh average Joe.

But thinking in up front investment isn't a strength of humans. We tend to want to pay as little early on as possible (and then complain about having to pay through the nose in post).

Also, as RC points out, a patent can assure that the invention is not stolen by an opportunist

I think you have it backwards. A patent is a way to bury an invention. if you make it 'open source' in the first place then no one can bury it.
bmont
not rated yet Apr 06, 2017
Revenue models exist beyond patent ownership, and given the nature of the players in this space, owning such a patent as this would garner extraordinary efforts to take control of the patent. If it were Creative Commons or similarly licensed, such that it was essentially open sourced, then no single party would control the tech, thus no single party could be induced to surrender such control to arguably evil, definitely extractive, pay-us-or-you-starve types of business models (looking at you, Monsanto). Beyond the totally valid profits-drive-innovation argument, open sourced agricultural tech would be a good thing, a la equip the world to feed itself. If open sourced, the tech could act more like a platform from which revenue models might emerge entrepreneurially to deliver, operate, and advance the tech among its users.

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