Engineered yeast for converting plastic and biomass compounds to food additives(acs.digitellinc.com) |
Engineered yeast for converting plastic and biomass compounds to food additives(acs.digitellinc.com) |
To make a fuel or food or other stuff out of it you need to define the microbes set(mixture). Almost every study claiming plastic to X follows hybrid pattern, they break the polymer into smaller molecules by depolymerization either thermally/chemically for polyolefins like PE/PP/PS, since no enzyme is known to break a C-C backbone; enzymatically for ester-linked plastics like PET/PU, via PETase-type enzymes). Then it goes to the fermentation process, resulting small molecules into lipids (most common), PHA, or specific chemicals.
Sometimes a consortium(Mixture of microbes) is used, with different microbes handling different fractions of the breakdown mixture. Any "protein from plastic" claim is the same logic, the depolymerized substrate is just feeding an yeast, and the protein is the yeast biomass itself, harvested and used crude or extracted.
True microbial degradation of intact plastic polymers, no pretreatment, organism doing all the work, is still a challenging task for biologist.
It kind of sounds like they made food out of corn plant stalks and leaves and "other biomass", added fiber, starch, and sweetener, but then just polluted the product with processed waste plastic as an additive. If this really is just using trash as a filler in actual food that's pretty dystopian. I'm sure companies would happily line up to sell their industrial waste products to food companies as an additive, but I'm not seeing the appeal in this for consumers.
PET consists of repeating C10H8O4 monomers. Glucose is C6H12O6 and starch is a natural polymer containing it. It's not surprising that reactions can turn one into the other, along with other compounds containing hydrogen, carbon, and oxygen.
Long answer: Starch and cellulose are just chains of glucose connected in a slightly different way. But they have very different properties, you can split starch and get energy from it, but you can't split cellulose (unless you are a bacteria or fungus).
As far as I know, no life form can transform starch directly into cellulose, they have to split it and reconnect the glucose later. (And the reverse path is even harder.)
There are a few cases where the cells can transform the monomers inside the chains, in particular to make collagen, but the change is to replace some -H by -OH. Changing the Carbon structure is harder, almost impossible.
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Back to the article: The yeast just split the plastic back into monomers (or probably short chains) and use the chains to build carotene (similar to vitamin A). It's quite similar to splinting starch or cellulose and using later the monomers. There is no polimer to polimer transformation.
Plenty of folks wishing to pretend though.
you, yes you, area "biomass compound", well maybe not quite yet, but soon, as these things go, but most definitly every last putrid smelly horrible thing is a "biomass compound", and when you add in plastic we are talking about most of the stuff found in millions of dumpsters, and most of the stuff actualy in dumps, or sewers.
This then solves the whole issue of what is allowed to go in which can or bin, which is anything you cant get money for or find someone who will hall it away for free.
I am very very sure that volunteers will soon show up wishing to "return to the great nutrient cycle"
but there is nothing to worry about as I am positive that everything will be tested and cynicly proven to be safe for human consumption
> With billions of people experiencing hunger in 2025 and unable to afford a healthy diet, food insecurity remains a critical global challenge.
You know where this is headed.
The primary issue that has consistently been a problem, is the cost.
I for one look forward to serving this underground deity.
If it could be done, we solve world hunger overnight.
Oddly many countries explicitly have a law that such a thing is forbidden. I wonder it it was preemptively protecting farmers?
Ultimately a tricky thing to define though, no argument.
Until, say, they mutate independently. Now, I have no idea how likely that is, but I think the fear is not baseless. There's a fun SF book, "Directive 51", which explores this a bit. Not a bad book to cuddle up with.
In a natural environment this will not hold. Organisms are unstable; they change all the time, simpler ones even more so. Mutants with a faster growth rate will, up to a certain maximum, take over from slower growing or growth-deficient mutants. There isn't really a compelling growth advantage for plastic-degrading organisms, which is one reason why plastic stays so long in the environment.
All pre-processing steps further add to the cost, so we will year after year hear about it - and then wonder why nothing happens and plastics keep compounding in the ocean. And this is not new either: https://en.wikipedia.org/wiki/Diamond_v._Chakrabarty
No wikipedia page, but goodreads has it here:
https://www.nytimes.com/1973/11/10/archives/soviet-plant-to-...
https://www.cia.gov/readingroom/docs/CIA-RDP91T01115R0001000...
The term to search for is "single cell protein."
There are newer approaches to making single cell protein from carbon dioxide and renewable energy instead of fossil oil, like Solein:
There are a few problems with turning oil into single cell protein:
- Microorganisms have small cells that reproduce quickly, which means a lot of nucleic acids in the dry mass, which is trouble for animals (including humans) that can't tolerate a very high purine level in the diet.
- The abundant cell walls of microorganisms also can cause illness when they're a high proportion of dietary intake.
- Feeding single cell protein directly to people has to overcome traditions of cuisine, even in cases where it doesn't actually make people sick. Indirect usage of SCP (e.g. feeding it to salmon, and then having people eat salmon) can overcome that hurdle, but then the cost per human-edible calorie goes up too.
Again, the ONLY reason there is still anyone, anywhere, who suffers from not enough food, is because people in the richest country on earth aren't even willing to spend a few million sending support to extremely needy countries.
Instead, we take a huge fraction of our entire corn crop, turn it into ethanol, and burn it. The primary reason we do it is to waste corn, so that corn prices are higher. We purposely make food more expensive, as a kickback to some real assholes.
World hunger could have been solved a century ago. No technology is required. Zero. At least until we have to figure out a reasonable way to make fertilizers more sustainable.
You know petroleum is actually expensive for a commodity, right? For the price of one barrel of oil, you could get an entire ton of iron ore, 0.8 tons of coal, 20 bushels of corn (about 1000-1200 pounds), 500 pounds of milk, 500 pounds of refined sugar, etc. Petroleum is an input to agriculture, but it enables staggering yield outputs per gallon of input. No amount of chemistry can ever compete with that for simple thermodynamics reasons.
Mechanized agriculture is so efficient that if you leave it to it's own devices it simply bankrupts itself every other year from oversupply. Damn near every functioning country artificially increases the price of basic agricultural commodities to ensure farms are stable. It's a massive handout to a cohort of people that nowadays are basically just very wealthy capital owners, but it also was the actual solution to famine, at least inside those countries.
Well that's where the yeast comes in, it does the work for us. And we desperately need ways to convert plastics into something that is not as durable, and ideally something we (or if that's too icky, farm animals) can eat afterwards.
That's how we got here in the first place.
I'm not sure if that's a dad joke or the microplastics in my brain telling me it is
Jurassic narratives notwithstanding, unsure if this is a real problem. If you have a yeast that will only survive under narrow unnatural circumstances, I would expect freeing it into the wild with natural circumstances means it dies - not uses nature to find a way to destroy the world as a form of poetic justice for ever having been created.
on edit: my confusion stems from being the first to reference anything Jurassic in the conversation, so you sound somewhat accusatory.