Spent brewer's yeast as a biosorbent for metal recovery from polymetallic waste | Hacker News Reader

Spent brewer's yeast as a biosorbent for metal recovery from polymetallic waste

frontiersin.org

93 pointsPaulHoule26 comments

I remember a company in Scotland using whiskey byproducts for metal decontamination

https://www.abc.net.au/listen/programs/scienceshow/barley-hu...

In England and some Commonwealth countries such as Australia and NZ we actually eat the stuff, Vegemite, Marmite, etc—much to the horror of others.

I hope supply damand brought about by this new innovation doesn't result in price hikes for our favourite spreads. :-)

“Yeast extract” gets snuck into a lot of American foods. You just don’t see it as a standalone product much. Marmite goes into plenty of my savory cooking

The stats on this look good. Do any biochemists have notes that would point to it being or not being worthwhile?

This is the first time I've seen the use of spent brewers yeast as the biomass for bioaccumulation. However, it falls short of addressing the economic feasibility of extracting the accumulated metals, an essential aspect for practical implementation.

The ability of fungi to absorb metals is well-documented, but the real-world application of fungi for purposes such as bioaccumulation and bioremediation is predominantly hindered by the economics, including high labor costs, expensive inputs, and slow processing times.

Hopefully in the future we can dump a bunch of used brewers yeast into a giant gold tailings pond and leech gold and other precious metals for cheap, but we're not there yet.

Extracting metals would be a bonus, removing them from wastewater and concentrating them in a mass that can be buried for later processing is boon enough for now.

    The presence of heavy metals in wastewater has been increasing with the growth of industry and human activities, e.g., plating and electroplating industry, batteries, pesticides, mining industry, rayon industry, metal rinse processes, tanning industry, fluidized bed bioreactors, textile industry, metal smelting, petrochemicals, paper manufacturing, and electrolysis applications.

    The heavy metal contaminated wastewater finds its way into the environment, threatening human health and the ecosystem. The heavy metals are non-biodegradable1 and could be carcinogenic; thus, the presence of these metals in water by improper amounts could result in critical health issues to living organisms.

Removal of heavy metal ions from wastewater: a comprehensive and critical review (2021)

https://www.nature.com/articles/s41545-021-00127-0

Heavy Metal Ions Removal From Wastewater Using Cryogels: A Review (2022)

https://www.frontiersin.org/articles/10.3389/frsus.2022.7655...

You can as well just bury the microelectronics directly

That just leaves the bulk of the metals as toxic waste in water supplies; the metal compounds from: plating and electroplating industry, batteries, pesticides, mining industry, rayon industry, metal rinse processes, tanning industry, fluidized bed bioreactors, textile industry, metal smelting, petrochemicals, paper manufacturing, and electrolysis applications, etc.

Correct, but you suggest to bury them just same. Given that other components of electronics like plastics are also toxic to water sources, you need to bury them with care in any case and I don't see why separate them in advance.

I'm involved in two different government-funded bioremediation projects that are exploring the use of fungi to remediate superfund sites. The challenge is not in fungi's ability to accumulate PFAS or heavy metals; it's in doing it cost-effectively over the current methods. As OP pointed out, in most cases, pollution is simply buried in a location that the EPA has designated safe for disposal.

am I the only one getting strong ChatGPT vibes here?

The first paragraph totally misses the point of any scientists discussion of this, which would center on the fraudulence level (esp. in a frontiersin-publication). Economic viability is important of course, but first results have to be robust...

Not disputing the potential ChatGPT, but I wouldn't harp on that top paragraph. The lab I work in does similar research (with inorganic materials) and virtually anything with anionic functional groups will work pretty effectively and more or less to the same degree. So the real question at this point is economic viability and local availability

Hands off my marmite!

Vegemite or bust.

I once uncovered a ten year old jar of Vegemite (90’s era). It was absolutely amazing. I’m not sure if it matured over time, or if they changed the recipe.

Marmite has an XO version¹, which is aged for a month instead of a couple of days. Not sure I want to try ten year old mitey, but you're here to tell the tale so it must be okay ;)

¹ https://www.marmite.co.uk/products/marmite-xo-yeast-extract-...

Why on earth is there a dancing jar of marmite taking up the bottom right sixth of the screen, and how do I get rid of it?

I'm interested in what aging means here. Presumably it is different to just 'having it in a jar in the cupboard' because then all jars are aged in the supermarket for a few weeks or more. Looks like I've got my afternoon wikipedia rabbit hole sorted.

From my experience it dries out rather than age, there's far too much salt in to age.

Please don't mess up the Vegemite supply chain

Any process that I'm aware of that uses yeast for something feeds the yeast, multiplying it and making it stronger. "Waste" brewer's yeast is more accurate, right?

Often there's a point of senescence or "getting old and slow" that can happen with strains.

This could bring a whole new dimension to 'Save water, drink beer!'

I swear I had just read "Spent browser yeast"

beer is not your thing, then.

What do you then do with the contaminated yeast?

How do you prevent it from entering the food chain again?

You can probably just burn it and recover the metals from the ashes chemically.

Sounds like people are trying to steal our Vegemite supply :D

[oh boo, u/zoklet-enjoyer beat me to it]

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