Proprietà nutraceutiche e attività antiossidanti di albicocche (Prunus armeniaca L.) trattate con un biostimolante a base di estratto di alghe marine e lievito

Prunus armeniaca L. fruits are well known around the world for their taste and nutritional values that vary among cultivars and agronomical conditions. Apricot production in Italy occupies the fifth place in the world making the quest for quality improvement attractive. Biostimulants are formulations consisting of pure compounds, mixtures of bioactive molecules, single microorganism strains, or consortia that if applied to plants improve the agronomic performance of agricultural crops. In the past, biostimulants have been widely investigated regarding their ability to provide tolerance to specific abiotic stresses. Today, many organic and inorganic substances together with microorganisms are being tested for their potential biostimulant activity on plants; humic and fulvic acids, protein hydrolysates, biopolymers as chitosan, macro and microalgae, fungi and bacteria are among the most promising. However, as much as plant physiological level responses are currently under investigation, scientific evidence regarding the quality of edible products from plants treated with biostimulant formulations is still very limited. In the following experimental thesis, changes related to the phytochemical profile, nutraceutical values, and antioxidant properties of two apricot cultivars (“Lady cot” having orange pulp and "Orange prima" with white pulp) were evaluated after treating Prunus armeniaca L. trees with three different dosages of biostimulant (5.0, 4.0, or 2.5 L/ha) or simply with water. Both edible tissues (pulp or peel) of the fruit were analysed. The analyses included both methodologies aimed at quantifying bioactive compounds and evaluating the functional (antioxidant) properties of the fruits. Biostimulant application positively affected chemical and phytochemicals parameters (antioxidant capacity, total content of phenols (TPC), total anthocyanin content (TAC), total flavonoid content (TFC), total carotenoid content (TCrC) and total flavan-3-ol content (TF3C)). Antioxidant capacity was significantly increased in skin in all treatments compared to pulp where results were inconsistent. The data obtained revealed that the application of biostimulant during ripening increased fruit quality without compromising agronomic yields. Consequently, the application of biostimulant can be a viable ecological and sustainable alternative for the production of fruits with improved nutraceutical value. ​