A team of Australian scientists is genetically engineering a common fly species so that it can eat more of humanity’s organic waste while producing ingredients for making everything from lubricants and biofuels to high-grade animal feeds.
Black soldier flies are already being used commercially to consume organic waste, including food waste, but tweaking their genetics could widen the range of waste their larvae consume while, in the process, producing fatty compounds and enzymes.
In a scientific paper, the team based at Sydney’s Macquarie University outlined their hopes for the flies and how they could also cut the amount of planet-warming methane produced when organic waste breaks down.
“We are heading towards a climate disaster, and landfill waste releases methane. We need to get that to zero,” Dr Kate Tepper, a lead author of the paper, said.
Dr Maciej Maselko runs an animal synthetic biology lab at Macquarie University where Tepper has already started engineering the flies.
Maselko said insects would be the “next frontier” in dealing with the planet’s waste management problem, which weighs in at about 1bn tonnes a year in food waste alone.
Black soldier flies are found in all continents except Antarctica. “If you’ve got a compost bin, then you’ve probably got some,” Maselko said.
The fly larvae can eat double their body weight a day and, like other insects, their larvae are used for animal feed. Maselko said the flies could already do the job of consuming waste faster than microbes.
Scientists are looking for ways to create circular economies, where waste is turned from being a problem to becoming part of a process of reuse and income generation.
The university team has created a spin-off company, EntoZyme, to commercialise their work and hopes to have the first genetically engineered flies for use in waste facilities by the end of the year.
But could the flies escape and generate unknown risks to the environment? Maselko said that as part of the genetic engineering, the flies can also be given weaknesses – such as an inability to fly – that make them unviable outside a waste processing facility.
The work to eat organic waste is done when the fly is in the maggot stage. The maggots, which then turn into pupae, are harvested.
Creating a suite of genetically engineered flies would see them also produce enzymes used in animal feeds, textiles and pharmaceuticals, and fatty compounds that can be used to make biofuels and lubricants.
Another proposed use is for some flies to be able to consume contaminated waste, which would then leave behind their poo that could be used as fertiliser.
Tepper said flies can be engineered to deal with pollutants in several ways, including by breaking pollutants down into less toxic or inorganic compounds, evaporating them into the air or accumulating some pollutants into their bodies that can then be separated, leaving clean organic waste behind.
The research and proposal is published in the journal Communications Biology.
