Bacteria Eats Styrofoam

[JazzRemington]

Immortal Styrofoam Meets its Enemy
By Robert Roy Britt
LiveScience Managing Editor
posted: 07 March 2006
09:27 am ET

There's an old joke that if you were reincarnated, you might want to come back as a Styrofoam cup.

Why? Because they last forever. Ba-dum-bum.

Despite being made 95 percent of air, Styrofoam's manufactured immortality has posed a problem for recycling efforts. More than 3 million tons of the durable material is produced every year in the United States, according to the U.S. Environmental Protection Agency. Very little of it is recycled.

Help may come from bacteria that have been found to eat Styrofoam and turn it into useable plastic. This is the stuff recycling dreams are made of: Yesterday's cup could become tomorrow's plastic spoon.

Kevin O’Connor of University College Dublin and his colleagues heated polystyrene foam, the generic name for Styrofoam, to convert it to styrene oil. The natural form of styrene is in real peanuts, strawberries and a good steak. A synthetic form is used in car parts and electronic components.

Anyway, the scientists fed this styrene oil to the soil bacteria Pseudomonas putida, which converted it into biodegradable plastic known as PHA (polyhydroxyalkanoates).

PHA can be used to make plastic forks and packaging film. It is resistant to heat, grease and oil. It also lasts a long time. But unlike Styrofoam, PHA biodegrades in soil and water.

The process will be detailed in the April 1 issue of the American Chemical Society journal Environmental Science & Technology.

http://www.livescience.com/technology/0603...rofoam_cup.html (http://www.livescience.com/technology/060307_styrofoam_cup.html)

[Atlas Swallowed]

I wonder if I put it on my inlaws if it will turn them into something useful. A plastic spoon would be a step up.

[TomRK1089]

Heh, quite amusing. I have relatives like that.

But on the serious side, that's a great way to turn a minus into an asset.

[Ol' Dirty]

Superb! Can't be too tasty for the bacteria though. :D

[Atlas Swallowed]

Is the new type of plastic going to be biodegradable or will our ancestors be looking at our plastic knives, spoons and forks instead of styrofoam?

[MysticArcher]

PHA can be used to make plastic forks and packaging film. It is resistant to heat, grease and oil. It also lasts a long time. But unlike Styrofoam, PHA biodegrades in soil and water.

I have a feeling they'll be fine


A very interesting article, good work JazzRemington

[Kia]

A great leap forward in reducing the amount of garbage covering our planet. My only worry is that does the bacteria produce any other chemicals/substances from disolving the styrafoam? Possibly more carbon dioxide or something more harmful?

[Atlas Swallowed]

Originally posted by [email protected] 10 2006, 07:19 PM

PHA can be used to make plastic forks and packaging film. It is resistant to heat, grease and oil. It also lasts a long time. But unlike Styrofoam, PHA biodegrades in soil and water.


I would like to know how long but it does sound like a vast improvement to the original.

[MysticArcher]

My only worry is that does the bacteria produce any other chemicals/substances from disolving the styrafoam? Possibly more carbon dioxide or something more harmful?

They definately make carbon dioxide, either because they're partially metabolising the styrofoam, or to power the enzymes that are breaking down the styrofoam

But probably not any more than they'd normally make digesting any other material.

I'd be interested in seeing the mechanism behind this;

Most likely they are metabolising the styrofoam, cleaving the polymer chain and then cleaving of parts of the individual monomers (the smaller molecular units that chain up to make polymers) and running those through the normal metabolic cycle

In which case it's interesting that the product of all this can itself assemble into a polymer, either on it's own or with bacterial enzyme help

Or they don't even break the chain and just cleave stuff off of the whole thing, but I think that's less likely due to the hindrance of the long styrene chain (hard to manuever an enzyme around a big chain like that)

[Severian]

Scientific American article (http://www.sciam.com/article.cfm?chanID=sa003&articleID=0007B0AE-88AF-13FF-88AF83414B7F0000)

Has some more detail which answers some of these questions.

But the bacteria thrived on this new diet, turning 64 grams of undistilled styrene oil into nearly 3 grams of additional bacteria. In the process, the bacteria stored 1.6 grams of the energy of the styrene oil as a biodegradable plastic called polyhydroxyalkanoates, or PHA. This plastic can stand up to heat but also breaks down more naturally in the environment than petroleum-based products. Thus, though the biology-powered process results in some toxic byproducts such as toluene and requires significant energy to drive the pyrolysis, it fuels hopes that Styrofoam--and the polystyrene molecule that makes it--can become more environmentally friendly.

Toluene is an organic solvent.

Also:
And the process might not just be useful for getting rid of disposable cups. "Due to the general applicability of pyrolysis for plastic conversion to an oil and the large number of microorganisms capable of PHA accumulation from a vast array of molecules, the principle of the process described here can be applied for the recycling of any petrochemical plastic waste," the scientists claim in the paper presenting their findings in the April 1 issue of Environmental Science & Technology. Apparently, bacteria recycle, too

[Atlas Swallowed]

God I hate those things. Die styrofoam peanuts, die die die!!!!!!

Its good to see science used for something useful instead of better ways to kill each other or a new consumer product for conveinance or vanity. It may sound stupid but stuff like this puts me in a great mood :)