Stress climatico e contenuto polifenolico in piante di olivo Bianchera

As is well known in the literature, the olive plant as a whole provides a precious set of nutritional elements with a high healthy power. This work is part of a larger project on the valorisation of the leaves of the Bianchera cultivar (a typical cultivar of Friuli Venezia Giulia), with the aim of formulating a nutraceutical preparation. The ultimate aim of the project is twofold: i) to use parts of the plant that normally are not considered into the olive oil production cycles, and ii) to meet the demands of consumers more concerned with health and willing to pay a premium for functional foods. In particular, in this preliminary study, leaves and olives from plants located in two areas differently affected by climate stresses, mainly due to the Bora, a cold wind from the northeast with gusts exceeding 180 km/h, have been analyzed. The leaves and olives were compared on the basis of the total polyphenol content, antioxidant activity evaluation, total flavonoid content, and a quali-quantitative analysis of phenolic compounds by HPLC. Overall, the content of polyphenols and the antioxidant activity of olive leaf extracts appeared to be higher than the fruit. The best results - leafs significantly rich in total polyphenols, and especially of hydroxytyrosol and oleuropein – would seem to be associated with olive plants which, although located at low altitudes (practically at sea level), are more exposed to the Bora gusts.