The voracious dipterans are capable of transforming organic matter into bioproducts useful for the production of advanced biofuels, biodegradable materials or agricultural fertilisers.
It is perhaps one of the best-known "laboratory" insects. The soldier fly (Hermetia illucens) features in a wealth of scientific publications and is used in a wide variety of projects: their larvae are extremely voracious and capable of transforming organic matter into by-products such as lipids, chitin and proteins. By-products that can subsequently be turned into advanced biofuels, biodegradable materials or agricultural fertilisers.
This is the project being developed by researchers at the Enea centre in Casaccia: feeding the dipteran's larvae on sewage sludge, manure and agri-food industry waste, in order to achieve what is known as bioconversion and thereby obtain new molecules. "What we are carrying out is the intermediate process: we take sludge from a wastewater treatment plant and feed soldier fly larvae on mixtures of this biomass with other substrates," Silvia Arnone of Enea's biomass and biotechnologies for energy laboratory explains to LifeGate. "At the end of development, the result is larvae — whose main components are lipids, proteins and chitin — and a residue (that is, what remains of the initial mixture, made up of larval exuviae and excrement) comparable to a soil amendment (fertiliser, ed.) for plant growth."
The insects in question are already being used today in similar processes. For example, the pupae (one of the insect's intermediate stages) are employed in the production of highly protein-rich animal meals. In some developing countries they can be used to reduce organic waste on the one hand and to feed livestock on the other.
In this case, Enea, in collaboration with the environmental entomology laboratory of the Istituto zooprofilattico sperimentale della Lombardia e dell'Emilia Romagna, has developed a small-scale "biorefinery" that aims to exploit materials destined for disposal in order to obtain advanced biofuels as well as new materials for green chemistry, such as bioplastics and biodegradable coatings, in line with the principles of the circular economy. "The initial biomass — that is, a waste product — becomes a resource as a source of raw material," researcher Arnone continues. And it could in the future produce the molecular basis for the production of fuels with a reduced environmental impact.