[ti:Plastic Eating Worms May Cut Pollution]
[by:www.21voa.com]
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[00:00.04]Researchers may have found an unusual way
[00:04.76]to reduce plastic pollution, one bite at a time.
[00:10.80]It turns out that the common wax worm can eat plastic.
[00:17.23]Also known as the Galleria mellonella,
[00:22.60]these worms may help reduce the waste caused by plastic bags.
[00:29.88]Each year, one trillion plastic bags are used around the world.
[00:36.96]They are made from polyethylene -- one of the strongest kinds of plastic.
[00:44.12]The wax worm is the larvae, or young form,
[00:49.60]of an insect called the greater wax moth.
[00:55.04]These kinds of worms are also called caterpillars.
[01:00.68]Federica Bertocchini is with the Institute of
[01:05.97]Biomedicine and Biotechnology of Cantabria in Spain.
[01:12.32]She says researchers found that the larvae of the Galleria mellonella
[01:19.77]are able to biodegrade the plastic bags.
[01:25.20]To "biodegrade" means to break down by natural processes or bacteria.
[01:35.60]They discovered this by accident, Bertocchini explains.
[01:41.76]She says the plastic bags holding the wax worms "became riddled with holes."
[01:49.76]In other words, the bags had holes all over them when the worms were inside.
[01:56.88]Bertocchini, a beekeeper, says she made the chance discovery
[02:02.92]after removing the worms from beehives, where they live.
[02:08.52]She put the worms in a plastic shopping bag,
[02:12.60]which became full of holes.
[02:15.76]Bertocchini worked with other researchers
[02:19.88]from the Spanish National Research Council
[02:23.20]and Britain's University of Cambridge's Department of Biochemistry.
[02:29.75]She carried out timed experiments on the worms.
[02:35.10]She says the worms can "do damage to a plastic bag in less than an hour."
[02:42.96]When 100 worms were placed in a normal British plastic shopping bag,
[02:50.40]the holes began to appear in just 40 minutes.
[02:55.52]After 12 hours, researchers saw "an obvious reduction in plastic mass."
[03:03.52]They say a single enzyme produced by the worm
[03:09.37]is responsible for the chemical process that breaks down the plastic.
[03:16.82]They also found that the worms turned the polyethylene
[03:22.84]into a different organic compound called ethylene glycol.
[03:30.25]It is used in making polyester fibers as well as antifreeze for vehicles.
[03:39.60]It is not clear if the worms produce enough for commercial use.
[03:46.96]Plastic is not the natural food for the wax worm.
[03:52.01]But the researchers say that since they lay their eggs in beehives,
[03:58.30]the larvae feed on beeswax.
[04:01.94]"Wax is a polymer, a sort of ‘natural plastic,'
[04:07.08]that has a chemical structure that is not dissimilar to polyethylene," Bertocchini says.
[04:16.84]Researchers say they still need to better understand
[04:21.68]how wax is digested, or processed, in the worm.
[04:26.60]Finding that out could lead to a solution for dealing with plastic waste.
[04:34.88]Bertocchini says they are planning to use this research
[04:39.64]to find a way to get rid of plastic waste.
[04:44.72]She says they are "working towards a solution to save our oceans,
[04:50.20]rivers and all the environment" from the problems of plastic waste.
[04:57.52]But, she adds, we should not throw polyethylene into the environment,
[05:03.64]"just because we now know how to biodegrade it."
[05:09.44]The study was published in the journal Current Biology.
[05:15.20]I'm Anne Ball.
[05:17.28]And I'm Bruce Alpert. 更多听力请访问21VOA.COM