Plastic-Eating Worms
Humans produce more than 300 million tons of plastic every year. Almost half of that winds up in landfills( 垃圾填埋场)， and up to 12 million tons pollute the oceans. qSo farthere is no effective way to get rid of it, but a new studysuggests an answer may lie in the stomachs of some hungry worms.
Researchers in Spain and England recently found that the worms of the greater waxmoth can break down polyethylene, which accounts for 40% of plastics. The team left 100 wax worms on a commercial polyethylene shopping bag for 12 hours, and theworms consumed and broke down about 92 milligrams, or almost 3% of it. To confirmthat the worms&39; chewing alone was notresponsible for the polyethylene breakdown, the researchers made some worms into paste( 糊状物)and applied it to plastic films. 14hours later the films had lost 13%of their mass--apparently broken down by enzymes( 酶)from the worms&39;stomachs. Their findings were published in Current Biology in Federica Bertocchini, co-author of the study, says the worms&39;ability to break downtheir everydayfood-beeswax--also allows them to break down plastic "Wax is acomplex mixture, but the basic bond in polyethylene, the carbon-carbon bond, is there as well, "she explains. "The wax worm evolved a method or system to break this bond. "
Jennifer Debruyn, a microbiologist at the University of Tennessee, who was notinvolved in the study, says it is not surprising that such worms can break downpolyethylene. But compared with previous studies, she finds the speed of breakingdown in this one exciting. The next step, DeBruyn says, will be to identify the cause ofthe breakdown. Is it an enzyme produced by the worm itself or by its gut microbes( 肠道微生物)? Bertocchini agrees and hopes her team ’s findings might one day help employ theenzyme to break down plastics in landfills. But she expects using the chemical in somekind of industrial process-not simply"millions of worms thrown on top of the plastic. ”
What can we learn about the worms in the study?