Abstract text: Olive mill waste is produced in substantial quantities during oil extraction, and its uncontrolled dispersion can disrupt ecosystems due to its complex and highly reactive organic composition. Nevertheless, these byproducts represent an underexploited biomass rich in bioactive compounds with potential elicitor activity1–3. Within the Horizon Europe OLinWASTE initiative4, sustainable extraction and separation processes were developed to recover biocompounds from OMW, supporting circular and low-emission agricultural practices.
Oligosaccharide profiling revealed that selected fractions are enriched in pectic and hemicellulosic oligosaccharides. Physiological and molecular analyses demonstrated that these fractions induce key hallmarks of plant innate immunity, including MAPK activation, hydrogen peroxide accumulation, and the expression of defence-related genes. Treatment with these molecules induces immune priming and enhances resistance in Arabidopsis thaliana and tomato plants against Botrytis cinerea and Pseudomonas syringae.
Overall, this study highlights the potential of valorising agro-industrial residues to improve crop performance under environmental constraints, reduce reliance on chemical inputs, and promote sustainable biomass utilisation.
1. Greco, M. et al. Plant Stress 14, 100655 (2024).
2. Greco, M. et al. Plant Physiology and Biochemistry 217, 109213 (2024).
3. Greco, M. et al. Environ. Sci. Technol. (2025)
4. https://www.olinwaste.eu/