Insect-Based Bioconversion Systems May Contribute to Antimicrobial Resistance

Strategic Insights -

Research conducted by the Marche Polytechnic University in Italy has raised concerns about the potential spread of carbapenem resistance genes (CRGs) in insect-based bioconversion systems. The study, published in the journal Genes, investigated the influence of different agri-food-based diets on the loads and CRG occurrence during the bioconversion process. The findings suggest that the diet composition may influence the proliferation of certain bacteria and the persistence of CRGs.

Key Takeaways:

  • The study used Hermetia illucens larvae to convert agri-food residues into high-protein biomass for animal feed and nutrient-rich frass for soil amendment.
  • Four experimental diets were formulated from agri-food residues and anaerobic digestate, including peas and chickpea waste, peas and wheat waste, onion and wheat waste, and wheat waste and digestate.
  • Plant-based diets sustained moderate loads, while the digestate-based diet led to a significant increase in both in the frass and mature larvae.
  • CRGs were detected only in legume-based diets: and were found in both mature larvae and frass, while and were found exclusively in either larvae or frass.
  • No CRGs were detected in onion- or digestate-based diets nor in young larvae or diet inputs.
  • The study concluded that careful substrate selection and process monitoring are essential to minimize antimicrobial resistance risks in insect-based bioconversion systems.

Statistics:

  • The study used 4 experimental diets formulated from agri-food residues and anaerobic digestate.
  • of CRGs were detected in legume-based diets.
  • of CRGs were found in both mature larvae and frass.
  • No CRGs were detected in onion- or digestate-based diets.
  • The study used 5 CRGs (, , and ) for quantification.
  • The study performed analyses on individual substrates, formulated diets, larvae (before and after bioconversion), and frass.

Sources:

  • Hermetia illucens Larvae Convert Agri-Food Residues into Valuable Biomass (Genes, 2025; 16(8):907)
  • Impact of Dietary Inputs on Carbapenem Resistance Gene Dynamics and Microbial Safety During Bioconversion of Agri-Food Waste and Anaerobic Digestate by Hermetia illucens Larvae (Mdpi, St Alban-Anlage 66, Ch-4052 Basel, Switzerland)