Solution to plastic menace: Grub that eats carrier bags!
IF you think moths are just pests that leave holes in your woolly jumpers, think again – they could come to humanity’s rescue.
Scientists have found a moth larva known as a ‘wax worm’ that loves to munch on plastic bags, a major source of land and sea pollution.
The greater wax moth normally eats beeswax, making them feared by beekeepers across Europe. But a chance discovery has shown that they will also happily eat plastic.
Placed in a bag, the larvae quickly leave it riddled with holes.
If scientists can recreate the way the larvae eat through the plastic, they could come up with a new way of disposing of bags and pack- aging which take decades to degrade naturally. Dr Paolo Bombelli, a member of the international team from Cambridge University, said: ‘If a single enzyme is responsible for this chemical process, its reproduction on a large scale should be achievable.
‘ This discovery could be an important tool for helping to get rid of the polyethylene plastic waste accumulated in landfill sites and oceans.’
The larvae live as parasites in bee colonies. A member of the research team from Spain, who happens to keep bees, spotted their taste for plastic while removing them from her hives. Dr Fed- erica Bertocchini, from the Institute of Biomedicine and Biotechnology of Cantabria in Santander, placed the larvae in a plastic shopping bag and later found it was full of holes.
Follow-up tests suggest it would take 100 worms around a week to eat an entire single use shopping bag weighing 1.3 grams. Beeswax consists of fatty compounds with a chain-like chemical structure similar to that of polyethylene, said the scientists.
The larvae are thought to digest beeswax and plastic in much the same way, by breaking down their chemical bonds, according to the research published in the journal Current Biology.
Dr Bombelli said the larvae produce ‘something that breaks the chemical bond, perhaps in its salivary glands or a symbiotic bacteria in its gut. The next steps for us will be to try to identify the molecular processes in this reaction and see if we can isolate the enzyme responsible.’
The larvae of the greater wax moth (galleria mellonella) are used by anglers as bait, and by bird and lizard keepers as feed.
They taste like a mix of pine nuts and Japanese enoki mushrooms and were said to be suitable for human consumption in a US government report. When fried, they explode like popcorn.
‘Breaking the chemical bond’