Global food insecurity is one of the current urgent problems, since around 343 million people are now facing high levels of it, notably in Gaza and Sudan, but also in pockets of South Sudan, Haiti and Mali. In addition, agriculture is increasingly under pressure to reduce pesticide use, ensure food safety and protect the environment. To face these challenges, the EcoPDI project aimed to create a new and sustainable antimicrobial approach based on photodynamic inactivation (PDI). PDI is a light-based disinfectant method that uses a compound called photosensitizer (PS) to produce reactive oxygen species (ROS). These species can destroy harmful pathogens without being toxic to the plant.
EcoPDI designed novel PSs from earth-abundant metals such as iron, copper, cobalt, zinc, and manganese, and combined them with natural PSs to produce environmentally friendly, light-activated antimicrobial agents.
The overall objective was to develop photosensitizers that can protect crops from resistant pathogens, such as bacteria that attack tomato plants or fruit trees like pears and apples, and fungi that affect citrus fruits. The project followed a triple-impact approach: sustainable (green chemistry, sunlight activation), economic (low-cost materials), and applicable (direct use in agriculture and food safety).