Effect of pre- and post-harvest treatments on quality, organoleptic and nutraceutical properties of wild edible plants

Wild traditional species of edible plants are considered a new source of bioactive compounds by consumers. A tentative to extend the knowledge about the wild edible plants was developed in the present thesis. Two promising species were selected by a preliminary screening: Sanguisorba minor Scop. and Rumex acetosa L. After the cultivation in hydroponic system, the two species were subjected to two consecutive cuts during the cultivation and were then stored as fresh-cut products and a metabolomic approach was utilized to evaluate the effect of the cut. The most representative class of flavonoids found in S. minor was flavones and, among them, apigenin, baicalein and 7,4’-dihydroxyflavone resulted the most representative. Three terpenoids with antimicrobic activity and two phenylpropanoid glycosides were isolated for the first time by R. acetosa species. During the cold storage (4 °C) of fresh-cut leaves of these species, the pattern of vitamin C content and antioxidant activity was constant and high, to indicate the retention of the nutraceutical value but also of the organoleptic characteristic of fresh-cut produce which did not turn brown. S. minor reported higher nutraceutical values when compared with common vegetables as well as with R. acetosa. After a further screening, a total of five species were selected, included the two species previously selected. The five species were analyzed when collected as wild or subjected to different growing techniques in terms of phytochemicals and nutraceutical properties, but also sensory profile. Plants grown in the open field showed nutraceutical and sensory profiles similar to those wild-collected. Finally, the most promising species in the research project, the S. minor species, was evaluated in terms of phenolic composition and nutraceutical properties, once subjected to different drying techniques (freeze- and oven-drying techniques). In the research project, it was successfully demonstrated that hydroponic cultivation could be a useful tool in the production of plant foods with an optimized bioactive content and health promoting properties. In addition, the potential of wild plants and S. minor, in particular, as a valuable source of nutraceuticals in the diet either in unprocessed or processed form was demonstrated.