The increasing global production of olive oil has brought with it significant environmental challenges. The waste generated by mills is often not disposed of in a controlled manner, causing soil damage and compromising microbial health due to the high content of tannins and phenolic compounds.

Sustainable management of agricultural waste is crucial for environmental protection. In response to this need, the team of researchers coordinated by Vincenzo Lionetti of the Charles Darwin Department of Biology and Biotechnology at Sapienza University of Rome has developed innovative green chemistry approaches to recycle olive mill residues, such as olive pomace, by transforming them into natural plant protection agents. The project, which resulted in two studies published in the journals Plant Stress and Plant Physiology and Biochemistry, also involved the Istituto della protezione sostenibile delle piante of the CNR in Bari, the companies AGROLIO and BIOENUTRA, and Spanish and Danish universities.

"The extracts obtained", says Lionetti, "also act as natural activators of plant immunity, stimulating innate defence mechanisms and enhancing the plants' ability to cope with infections".

By preparing the immune system, the natural extracts identified are an environmentally friendly alternative to chemical pesticides, thus helping to reduce the environmental impact of synthetic solutions and supporting more nature-friendly farming practices.

Some of these bioactive compounds have shown significant antimicrobial properties, particularly effective against pathogens such as Xylella fastidiosa, Pseudomonas syringae and Botrytis cinerea. These pathogens attack various plant species, causing symptoms such as rot, wilting and, in some cases, severe desiccation that threaten valuable crops such as olive trees.

"This innovation therefore offers new opportunities to use the by-products of oil mills, transforming agricultural residues into valuable tools for the integrated management of various pests", says Lionetti. "It also promotes a sustainable circular economy in the agri-industrial sector, helping to reduce the use of pesticides that are harmful to human health and the environment".

This research has been supported by several projects including the Topic Line 2- Bioenergy and Green Chemistry within the Rome Technopole innovation ecosystem led by Sapienza together with REACH-XY funded by MUR and MEF and other projects.

References:

Upcycling olive pomace into pectic elicitors for plant immunity and disease protection - Greco M., Kouzounis D., Fuertes-Rabanal M., Gentile M., Agresti S., Schols H.A., Mélida H. e Lionetti V - Plant Physiology and Biochemistry (2024) https://doi.org/10.1016/j.plaphy.2024.109213

Phenolic compounds-enriched extract recovered from two-phase olive pomace serves as plant immunostimulants and broad-spectrum antimicrobials against phytopathogens including Xylella fastidiosa - Greco M., Fuertes-Rabanal M., Frey C., Del Grosso C., Coculo D., Moretti P., Saldarelli P., Agresti S., Caliandro R., Mélida H. e Lionetti V - Plant Stress (2024) https://doi.org/10.1016/j.stress.2024.100655.

Further Information

Vincenzo Lionetti
Department of Biology and Biotechnology "Charles Darwin "
vincenzo.lionetti@uniroma1.it