New technological approaches for recovering bioactive food constituents from sweet cherry (Prunus avium L.) stems

Abstract

In recent years, an increasing interest in biological properties of sweet cherry (Prunus avium L.) stems has resulted in increased attention for advanced extraction techniques and their optimisation. Objectives: In the present study chemical profiles of P. avium stems extracts obtained by selected emerging technologies, such as pressurised liquid extraction (PLE) and supercritical fluid extraction (SFE), under different experimental conditions were compared. Material and Methods: All SFEs were carried out at 40°C in a dynamic mode with different solvent combinations (CO2 plus ethanol at 7 and 15%) and pressures (150 and 300 bar). The PLE experiments were performed in a static mode for all tested combinations of extraction solvent (ethanol–water from 0% to 100%) at temperatures ranging from 40 to 200°C. A complete analytical characterisation of cherry stem extracts was performed by high-performance liquid chromatography coupled to electrospray ionisation quadrupole time-of-flight mass spectrometry (HPLC-ESI-QTOF-MS). Results: PLE showed to be more efficient than SFE removing a wide variety of compounds with different polarities being phenols the most abundant, whereas SFE resulted in a higher amount of fatty acids and derivatives. Chemical characterisation of the extracts was carried out by HPLC-ESI-QTOF-MS yielding in total 42 identified compounds, among which 22 compounds were identified in P. avium stems for the first time. Conclusion: These results point out the possibility of sweet cherry stem extracts to be incorporated in formulations manufactured by food and pharmaceutical industry. Also, these new thermal and high-pressure industrial technologies proved to be promising candidates in the valorisation of sweet cherry by-product.