Recupero di composti fenolici da materiale di potatura dell'olivo

The pruning is an expensive and necessary agronomical work of the chain of production of the olive oil. The resulting woody and leaf material is often crushed and spread on the soil, or burned. But, if well utilized, it could be a resource. An exploitation which seems promising is the extraction of various classes of compounds, especially polyphenols, among which some are peculiar of the olive tree and show interesting biological and chemical properties. In this work two methods of extraction of phenolic compounds from olive leaves were qualitatively investigated in order to evaluate their potential application in small factories. In the experiments carried out phenolic compounds like oleuropein and flavonoids and other compounds like chlorophyll were separated. Besides, the possibility of further utilization of the solid residue after the extraction of phenols was also estimated. Nevertheless it was also noticed that, in order that the extraction of phenolic compounds from the olive tree trimming might be advantageous, this material, devoid of pesticides, must be suitably processed for inactivating endogenous enzymes, which could affect phenolic compounds,. From the examination of the preliminary experiments carried out, although only qualitative, it could be concluded that harvesting, stabilization and preparation of the olive tree trimmings could be done in the farms, whereas the extraction of the phenolic compoundscould be done only by trained personnel in factories equipped with suitable structures for their separation and storage and for the use of solvents. In this way, by a careful selection of solvents and reagents, the recovery of phenolic compounds from this material could be, as well as profitable from an economic point of view, also sustainable for the soil and the environment.