APR 27

Scientists from the University of South Florida have discovered the water purifying power of the prickly pear cactus.  An extract from the desert-dweller is very effective at removing sediment and bacteria from dirty H2O and, even better, it grows all around the world.

The scientists aren't the first to realize this plant's ability.  Nineteenth-century Mexican communities used the cactus as a water purifier. The thick gum in the cactus that stores water is responsible for the purification.  The scientists extracted the gum and then added it to water that had been dirtied up with sediment and bacteria.

The gum caused the sediment and bacteria to combine and settle to the bottom, filtering 98 percent of the bacteria from the water.  The next phase is to test it on natural water.

The scientists see communities in developing countries using the cactus on daily basis.  They could boil a slice of it to release the gum and then add it to water just like the scientists did.  But there are hurdles to overcome.  What resources would be necessary for widespread growth of the cactus for this purpose and how can people ensure the "treated" water is truly bacteria free?  If these problems can be solved, cheap, clean water could be accessible for millions who are currently without.

via New Scientists

Comments (13)

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Nineteenth-century Mexican communities used the cactus as a water purifier
written by Eric G, April 27, 2010

"Nineteenth-century Mexican communities used the cactus as a water purifier" so technically the researchers took something that was already discovered in Mexico and are taking credit for it?

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written by Australia Joe, April 27, 2010

It does grow all over the world, but that's not necessarily a good thing! Over here it's an invasive species, and a pest!

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written by sarah, April 27, 2010

I've always thought it was tangy and kind f delicious. if I'm eating it is it purifying on the way down?

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The stupidity of these researchers is astounding
written by Fred, April 27, 2010

The prickly pear cactus laid waste to huge tracts of Australia in the 19th and 20th centuries, rendering the land unsuitable for agriculture and farming. It displaced native species and enabled massive soil erosion.

Australia was only saved by the use of a biological countermeasure http://en.wikipedia.org/wiki/Cactoblastis_cactorum

What is to stop this cactus from taking over and becoming an invasive pest in other countries, rendering them unable to grow food?

Time to think again 'scientists'.

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YUM!!!!!
written by Rambo Brite, April 28, 2010

My mom used to make nopales (Noh-Pahl-ess) when I was a kid growing up. Cooks great with eggs, chorizo. As a food source its awesome, and easily flavored. And like Aloe Vera, so long as you can get past the sliminess, are great on clearing the throat. Scientists, Schmientists.... A resurgence of interest is whats needed, who cares if they "re-discovered" it. As long as its being put to a good use. So quit yer f--ing crying. Waaaaaaaaaaaaaaaa!!!!!

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written by Bob, May 06, 2010

Fred, aren't you overreacting just a bit? I didn't see anything in the story suggesting that these scientists were advocating planting the stuff. Apparently it grows pretty much anywhere the climate is suitable already. Wouldn't it be nice to know that there is something useful that can be done with it? Especially since so many people have no access to clean water?

Besides, it isn't like the stuff grows all that fast (we have it here too, and it hardly takes over "vast tracts"), so I think any interference with agriculture is unlikely. In the case of Australia, I'm just guessing, but was it affecting the growth of crops or was it affecting rangeland used by cattle? There's a big difference. On a farmer's field, it's easy to remove. On rangeland, it would be a problem, but I think that's more an issue for commercial ranchers.

Besides, scientists regularly study chemicals found in all manner of unpleasant plants, insects, etc. and that doesn't mean they are advocating spreading the things all over simply because they find something useful.

The scientists ARE thinking. It's you who are simply reacting.

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I say, let's all eat nopales
written by elizabethmadrigaleditor, May 06, 2010

Lived in Mexico City for three years and developed a taste for nopales within a week. Using the green jalapeno/onion/tomatillo sauce made them simply divine, and they are not in any way fattening. Personally I would be more concerned there were not enough of these cacti, as they are often the only thing that can grow on over-ranged and desert areas.

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written by mthead, May 06, 2010

Thanks Megan. I'd also like to mention that the Prickly Pear leaves are used to treat and even cure Diabetes. I'm trying to grow some in Southern Louisiana. Very wet climate here but so far my little cactus is still alive.

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written by Chelsea, May 15, 2010

The tap water at USF tastes like chlorine and has total hardness levels waaaaay above the maximum of what it should be. Hopefully in the future we can change that and have a water purification system like this instead!

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Fred??
written by Covey, May 27, 2010

Fred??
I think they are referring to a cactus plant not the insect you seem to be referring to.
Just an observation..

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Stop introducing things into Australia then.
written by Matt, June 23, 2010

The cactus only became a massive issue when they introduced to an uncontrolled environment. Maybe Australia should stop importing frogs and cactuses, etc so these major ecological issues don't keep popping up down there.

A better wiki link would have been this: http://en.wikipedia.org/wiki/P..._Australia

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Nature is amazing
written by Dave, August 05, 2010

Finding a nature filter that can remove "98 percent of the bacteria from the water" is amazing. Don't most cactus grow almost anywhere? It is crazy to think that people today can not get clean water to drink.

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Homemade Water Filters
written by Noah Minard, May 09, 2012

Wouldn't it be easier to just put some water in a clear 2 liter bottle and throw it in the sun for a few hours? Seems like mixing in cactus is a lot of work!

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