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Scientists complete starch synthesis from CO2, revolutionary for agricultural (globaltimes.cn)
98 points by hourislate on Sept 26, 2021 | hide | past | favorite | 46 comments



From the paper in question[1]

"carbon dioxide is reduced to methanol by an inorganic catalyst and then converted by enzymes first to three and six carbon sugar units and then to polymeric starch. This artificial starch anabolic pathway relies on engineered recombinant enzymes from many different source organisms and can be tuned to produce amylose or amylopectin at excellent rates and efficiencies relative to other synthetic carbon fixation systems—and, depending on the metric"

https://www.science.org/doi/10.1126/science.abh4049


Good idea for the wrong product. Does not make sense to make food out of it, at least not on earth.

"carbon dioxide is reduced to methanol by an inorganic catalyst"

The methanol can be used as fuel.

https://en.wikipedia.org/wiki/Methanol_economy


The catalyst is the part I'm most curious about. Carbon capture is a hard problem at scale. Once you have methanol, I'm not terribly surprised that you can convert it to other things enzymatically. Hard to evaluate without full text of paper though.


A lot of people are dismissive, and to be honest, I'm a bit skeptical too.

But this is fundamentally an absolutely great idea. If anyone is able to crack this nut, then this could be a more momentous invention than the Haber-Bosch process.

Here's why: at this point all food produced on Earth starts from the point where photosynthesis produces a molecule of sugar. That reaction is terribly inefficient at 1-3% efficiency. At least in principle it should be possible to synthetically produce glucose and other sugars at a higher efficiency. This paper [1] goes into more details.

Once you get synthetic sugars or starch, you can use them as feedstock for other things. Aquaculture, poultry, mushrooms, etc.

[1] https://www.frontiersin.org/articles/10.3389/fsufs.2020.0009...


I am somewhat dismissive, not of the process but of the end outcome itself.

Industrial scale carbon capture only makes sense, if we are going sequester it and remove the carbon from the ecosystem. If we are just going to make fuel/food out of it, it would make no difference to our Climate woes, other than perhaps buy us some time.

I guess, that's still better than what we have, but I can't help think of these as half measures.


The largest industrial carbon capture facility we have built will mitigate ~3 seconds of global warming in a year. It won't get us anywhere without net zero emissions, even if we assume improvements of multiple orders of magnitude. Even a magic material that perfectly binds to atmospheric CO2 would require rounding up molecules in numbers I don't know the English for. This does open up the possibility of using the 1/3rd of arable land (26% of the terrestrial surface) being tied up growing feed as forests again, though. According to Current Affairs, re-foresting 70% of our terrestrial surface (not possible without drastic food production and consumption changes) would mitigate 1/10th of our global emissions. It's a lot of CO2 we're talking about, your car (if you have one) on average releases a metric ton of the stuff every 2000 miles.


3 seconds of global emissions*


> Preliminary lab tests show that synthetic starch is about 8.5 times more efficient than starch produced by conventional agriculture. Under the condition of sufficient energy supply and current technical parameters, the annual production of starch of 1 cubic meter bioreactor is equivalent to the annual production of starch of 5 mu (0.33 hectare) of corn in China.

Ah of course, leaving aside the small issue of energy use this process does indeed seem very efficient


I suppose the upside could be that you _could_ imagine (if, of course, the whole thing was efficient enough) a process where you use low-carbon electricity (nuclear or poorly-timed renewables) to power CO2 capture from air, and then turn the CO2 into starch, and then maybe turn the starch into something edible ? (I don't have enough grain of salts to take my own words here...)

It's a huge stretch to image that being competitive with conventional agriculture. Still, just imagining a situation where we could use electricity to turn CO2 into food...


There may be places where you would want access to starches, agriculture is not feasible, transportation costs are prohibitive, but you also have abundant power. I’m struggling to think of a place that meets all those criteria.


Near Arctic regions like Lappland where I live fit the bill:

* plenty of hydro power (which is why there’s data centers and battery recycling);

* agriculture isn’t possible outside with no sun and meters of snow; there’s greenhouses, including opaque ones with purely electric lighting but it’s expensive;

* transport by road is common, but harder in winter without fossil fuels and battery uncomfortable at -40ºC/F.

Any local activity could generate CO2, but the biggest existing one is paper mills.


If it's really more efficient than plants, then it would make sense to have solar panels combined with this process also in places where agriculture is feasible and there are no issues with transportation costs.


On a spacecraft with solar panels?

The desert maybe?


Mars?


there's not much co2 on Mars


Leaving aside the future improvements(50% larger plants) in agriculture as well:

https://futurism.com/the-byte/splice-human-gene-potatoes



Can't you go from starches to plastics? So, wouldn't this allow fossil fuel free plastic, without having to convert land from food to plastic production?

https://en.wikipedia.org/wiki/Bioplastic


the very first intermediate is methanol (produced chemically in one step via hydrogenation in this paper, using a known method) so you can just use methanol to polymers via method of choice, e.g. [0] no need to convert to starch first.

[0] https://pubs.acs.org/doi/10.1021/acscatal.5b00007


Taking this news with a grain of salt, with obvious reasons.


Because starchy foods are delicious with a bit of salt?


Every time I read the Global Times I find myself wondering "how does a propaganda paper for a country with 1.4 billion people still not know how to write things that don't sound like blantant propaganda?"

You'd think, with all their resources, they could have hired someone a bit more learned in the gentle art of subtlety.


We are not the target audience


Another almost content free press release.

I wish that there could be some standard that press releases would adhere to that would require them to link to authoritative documents and to include statements of energy efficiency, etc.



Sounds like huge news for space exploration and colonization. First step in building a Star Trek replicator?


Cool though the development in the article is, everything I hear about space colonisation says that to make it viable you need power and physical space on a scale that isn’t significantly harmed by “just” using hydroponics and aeroponics, and the hardest problem in any case is the protein rather than the calories.

(That and Trek replicators being much to fast for any mechanism we currently know about, so think “better bread machines” until someone can demonstrate 3D printing with IDK atomic quantum holography or something).


Protein from hydrocarbons was available since at least seventies. Google paprin, and gaprin. Paprin is yeast eating paraffin, gaprin is methane oxidising bacteria.

I myself ate a porridge of paprin once when the food situation in Russia was bad enough.


Interesting is this what you are referring to

>In the Soviet Union, the first production of feed protein from hydrocarbons took place in the 1970s. In total, the country built 12 plants with a designed production performance of around 1 million tonnes per year. This was close to 70% of the world’s bioprotein production at that time. The importance of the bioprotein industry in the country was comparable with that of the nuclear industry, since it allowed the Soviet Union to be self-sufficient in feedstuffs.[1]

According to the article[1] the paprin caused health issues for the animals fed on it and health problems for the people who ate the the meat obtained from the animals.

>Paprin had a devastating impact on animal health. This product disturbed the hormonal and water balance, causing the formation of oedema all over the animals’ bodies, the Russian Business Consulting agency reported, citing research by the Bashkiria State University. Meat obtained from these animals was causing flare-ups of chronic diseases in consumers. “Meat obtained from animals fed with Paprin contained an accumulation of abnormal amino acids that were incorporated into the membranes of nerve cells, thus disrupting the process of conducting a normal nerve impulse,” said Raisa Bashirova, senior researcher at Bashkiria State University. She added that it was even dangerous for humans to work with Paprin: “The workers at the plants and local residents were developing diseases such as thrush and bronchial asthma.”

While the grapin was proved to be safe.

[1]https://www.allaboutfeed.net/all-about/new-proteins/bioprote...



Now we just need to figure out how to scale it up to capture 45 Billion Metric Tonnes of greenhouse gases produced by humans yearly.


If this is true, it spells the end of traditional farming practices and an end to starvation.


That depends on how much energy is required. It does mean that settlements in places like the Yukon and Northern Alaska are now much more interesting.


Pack the far north with SMRs, use the electricity to power CO2 capture farms and make starch, and the waste heat can heat homes. Northern Alberta never looked so good.


I think energy is going to get a lot cheaper in the coming years. Especially at times when renewables are overproducing.


Can anyone explain how this works?


See jarenmf's comment. Basically the CO2 is catalyzed into Methane using an 'inorganic catalyst', there is this paper[1] which uses a ruthenium catalyst at 400 degrees C to do it.

Then the methane is consumed by some genetically modified bacteria (probably e.coli) first to convert it to an intermediate product, and then with a second organism to convert it into starch.

In the article they talk about genetically modified enzymes and I've actually jumped ahead to the using genetically modified bacteria here[2]. I think that is a safe assumption as a number of bio-reactors do exactly this.

What is somewhat interesting to me is that livestock generates a lot of methane, if you could harvest it and convert it back into starch to feed the livestock you could increase the efficiency of raising livestock farming.

[1] https://phys.org/news/2020-02-method-carbon-dioxide-methane-...

[2] The article hasn't appeared in sci-hub yet :-)


Most of the methane comes from cattle belching, so it's basically impossible to harvest at scale. The lagoons of manure also do, and that can be harvested though it's hard.

https://climate.nasa.gov/faq/33/which-is-a-bigger-methane-so...


I came up with this solution: https://i.imgur.com/8BNktVY.png


I nominated you for IgNobel 2022


the CO2 is converted to methanol not methane. theoretically 3 equivalents of dihydrogen (which you need energy to produce) are needed per CO2. the hydrogenation requires veery high concentrations of CO2 (energy needed to concentrate it) and H2 so from the energy point of view it is not that good. however from the point of view of bio-engineering it is a really nice result


> ...requires veery high concentrations of CO2 (energy needed to concentrate it)...

I wish we had a process similar in efficiency to a heat pump that moves gradients of diffuse molecules than thermal energy. But the osmotic pressure or other diffuse gradient movement methods I'm aware of are quite energy intensive.


Agreed, this result is more about creating 'food' without plants than it is saving costs. The useful thing is that it shows a path for out-of-ecosystem food production which will be useful in places like Mars or a Lunar colony.


"CO2 is catalyzed into Methane using an 'inorganic catalyst', there is this paper[1] which uses a ruthenium catalyst at 400 degrees C" that either alchemy or more energy consuming than agriculture. "Silver-gray ruthenium metal looks like platinum but is rarer," - great to keep the costs down and avoid wars in places like congo eh? ;)


Thanks. Isn’t it cheating to use bacteria? I thought this was all synthetic.


Even the news article didn't care to explain the process.




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